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\declaretheorem[name=Theorem,numberwithin=section,style=plain]{theorem} \declaretheorem[name=Proposition,sibling=theorem,style=plain]{proposition} \declaretheorem[name=Lemma,sibling=theorem,style=plain]{lemma} \declaretheorem[name=Corollary,sibling=theorem,style=plain]{corollary} \declaretheorem[name=Claim,sibling=theorem,style=plain]{claim} \declaretheorem[name=Theorem,numbered=no,style=plain]{theorem*} \declaretheorem[name=Definition,sibling=theorem,style=definition]{definition} \declaretheorem[name=Construction,refname={Construction,Constructions},Refname={Construction,Constructions},sibling=theorem,style=definition]{construction} \declaretheorem[name=Certificate,refname={Certificate,Certificates},Refname={Certificate,Certificates},sibling=theorem,style=definition]{certificate} \declaretheorem[name=Hypothesis,refname={Hypothesis,Hypotheses},Refname={Hypothesis,Hypotheses},sibling=theorem,style=definition]{hypothesis} \declaretheorem[name=Remark,sibling=theorem,style=remark]{remark} \declaretheorem[name=Example,sibling=theorem,style=remark]{example} \numberwithin{equation}{section} \newcommand{\N}{\mathbb N} \newcommand{\Z}{\mathbb Z} \newcommand{\Q}{\mathbb Q} \newcommand{\R}{\mathbb R} \newcommand{\C}{\mathbb C} \newcommand{\F}{\mathbb F} \newcommand{\Fp}{\mathbb F_p} \newcommand{\Zsix}{\Z/6\Z} \newcommand{\E}{\mathbb E} \renewcommand{\Pr}{\mathbb P} \newcommand{\one}{\mathbf 1} \newcommand{\ind}[1]{\mathbf 1_{\{#1\}}} \newcommand{\abs}[1]{\left|#1\right|} \newcommand{\norm}[1]{\left\|#1\right\|} \newcommand{\ip}[2]{\left\langle #1,#2\right\rangle} \newcommand{\opnorm}[1]{\left\|#1\right\|_{\mathrm{op}}} \newcommand{\eps}{\varepsilon} \newcommand{\dd}{\,\mathrm d} \newcommand{\Var}{\operatorname{Var}} \newcommand{\supp}{\operatorname{supp}} \newcommand{\rad}{\operatorname{rad}} \newcommand{\lcm}{\operatorname{lcm}} \newcommand{\diag}{\operatorname{diag}} \newcommand{\tr}{\operatorname{tr}} \newcommand{\Unif}{\operatorname{Unif}} \newcommand{\PSD}{\succeq} \newcommand{\e}{e} % e(t) = exp(2 pi i t) is written \ee \newcommand{\ee}[1]{e\!\left(#1\right)} \newcommand{\Qsq}[1][p]{Q_{#1}^{*}} % nonzero squares mod p \newcommand{\Ap}[1][p]{A_{#1}} % indicator of nonzero squares \newcommand{\Om}[1][p]{\Omega_{#1}} % strict-square pairs \newcommand{\Xs}[1]{X_{#1}} % product of prime fields over a prime set \newcommand{\Vslots}{V} % slot set (Z/6)^2 x {0,1} \newcommand{\rot}{\mathsf c} % rotation on Z/6 \newcommand{\Rel}{\mathsf R} % relation y in {x, x+-1, c(x)} \newcommand{\Pone}{P_1} \newcommand{\Ptwo}{P_2} \newcommand{\Pthree}{P_3} \newcommand{\Pfour}{P_4} \newcommand{\Mmod}{M} % small modulus 8 prod_{3<=p1$}}{419}{section.1964}% \contentsline {paragraph}{\tocparagraph {}{}{What this section proves and how to read it.}}{419}{section*.1965}% \contentsline {subsection}{\tocsubsection {}{26.1}{A joint $2\times 2$ block for reference and comparison records}}{420}{subsection.1966}% \contentsline {paragraph}{\tocparagraph {}{}{Auxiliary sides and the certified price.}}{421}{section*.1969}% \contentsline {paragraph}{\tocparagraph {}{}{The global substitution.}}{423}{section*.1977}% \contentsline {subsection}{\tocsubsection {}{26.2}{The sides of the signed law}}{424}{subsection.1978}% \contentsline {subsection}{\tocsubsection {}{26.3}{The dominators $M_{\rm L},M_{\rm R}$ and the total $T$}}{425}{subsection.1985}% \contentsline {paragraph}{\tocparagraph {}{}{The matching exponent.}}{426}{section*.1986}% \contentsline {subsection}{\tocsubsection {}{26.4}{The common mean for the selected law}}{427}{subsection.1992}% \contentsline {subsection}{\tocsubsection {}{26.5}{Mean energies exceed $mY$ with $m>1$}}{428}{subsection.1994}% \contentsline {paragraph}{\tocparagraph {}{}{Notation.}}{428}{section*.1995}% \contentsline {subsection}{\tocsubsection {}{26.6}{Allocating the full positive mean jointly with the comparison}}{431}{subsection.2003}% \contentsline {paragraph}{\tocparagraph {}{}{Residual coefficients.}}{433}{section*.2015}% \contentsline {paragraph}{\tocparagraph {}{}{Hypotheses verified in this section.}}{434}{section*.2018}% \contentsline {paragraph}{\tocparagraph {}{}{Consequences and what to read next.}}{435}{section*.2019}% \contentsline {section}{\tocsection {}{27}{Upper primes I: the reference law $\mu $ and its spectral bounds}}{435}{section.2020}% \contentsline {paragraph}{\tocparagraph {}{}{What this section proves and how to read it.}}{435}{section*.2021}% \contentsline {subsection}{\tocsubsection {}{27.1}{The $310$ bands and their input data}}{436}{subsection.2022}% \contentsline {paragraph}{\tocparagraph {}{}{Where the upper range starts.}}{436}{section*.2023}% \contentsline {paragraph}{\tocparagraph {}{}{Class three.}}{437}{section*.2024}% \contentsline {subsection}{\tocsubsection {}{27.2}{The two-layer reference}}{438}{subsection.2038}% \contentsline {subsubsection}{\tocsubsubsection {}{27.2.1}{The two-layer graphs}}{438}{subsubsection.2039}% \contentsline {paragraph}{\tocparagraph {}{}{How to read the two-letter names.}}{438}{section*.2040}% \contentsline {subsubsection}{\tocsubsubsection {}{27.2.2}{The $25$ summand types}}{439}{subsubsection.2047}% \contentsline {subsubsection}{\tocsubsubsection {}{27.2.3}{The reference law $\mu _\mathcal B$ and its weights}}{440}{thmt@dummyctr.2049}% \contentsline {subsection}{\tocsubsection {}{27.3}{The two principal cuts}}{440}{subsection.2052}% \contentsline {paragraph}{\tocparagraph {}{}{The setting.}}{440}{section*.2053}% \contentsline {paragraph}{\tocparagraph {}{}{Route\nonbreakingspace B at the two root cuts.}}{441}{section*.2055}% \contentsline {paragraph}{\tocparagraph {}{}{Where the root cost lies.}}{444}{section*.2070}% \contentsline {paragraph}{\tocparagraph {}{}{Route A from $2^{52}$: the completed root.}}{444}{section*.2071}% \contentsline {subsubsection}{\tocsubsubsection {}{27.3.1}{Cross-weighted root refinement and the final reference}}{445}{subsubsection.2078}% \contentsline {subsection}{\tocsubsection {}{27.4}{The ten non-principal cuts}}{446}{subsection.2081}% \contentsline {subsection}{\tocsubsection {}{27.5}{Merge and constant bounds for four states}}{448}{subsection.2088}% \contentsline {subsection}{\tocsubsection {}{27.6}{Conditional laws given the middle label}}{450}{subsection.2091}% \contentsline {subsubsection}{\tocsubsubsection {}{27.6.1}{The product reference and the star bounds}}{450}{subsubsection.2092}% \contentsline {subsubsection}{\tocsubsubsection {}{27.6.2}{Differences of conditional laws given the middle label}}{451}{subsubsection.2093}% \contentsline {paragraph}{\tocparagraph {}{}{Complete conditional means.}}{452}{section*.2094}% \contentsline {paragraph}{\tocparagraph {}{}{Exact output supports.}}{452}{section*.2097}% \contentsline {paragraph}{\tocparagraph {}{}{The six-density Gram matrix.}}{452}{section*.2100}% \contentsline {paragraph}{\tocparagraph {}{}{Weighted moving-root moments.}}{453}{section*.2103}% \contentsline {paragraph}{\tocparagraph {}{}{Signed grouping of the principal supports.}}{453}{section*.2106}% \contentsline {paragraph}{\tocparagraph {}{}{Strict injection, normalization and the differences.}}{454}{section*.2110}% \contentsline {subsubsection}{\tocsubsubsection {}{27.6.3}{Exact-support correlations}}{455}{subsubsection.2114}% \contentsline {paragraph}{\tocparagraph {}{}{Full star matrices (bands).}}{455}{section*.2117}% \contentsline {subsubsection}{\tocsubsubsection {}{27.6.4}{Fold and matching conditional laws bounded jointly}}{456}{subsubsection.2118}% \contentsline {subsection}{\tocsubsection {}{27.7}{Band input formulas (F1)--(F6) and (F10): definitions}}{458}{subsection.2125}% \contentsline {subsection}{\tocsubsection {}{27.8}{(CP1) for upper atoms}}{460}{subsection.2133}% \contentsline {paragraph}{\tocparagraph {}{}{Consequences and what to read next.}}{462}{section*.2143}% \contentsline {paragraph}{\tocparagraph {}{}{Hypotheses verified in this section: (CP1) for upper atoms.}}{462}{section*.2144}% \contentsline {section}{\tocsection {}{28}{Upper primes II: the comparison law $\nu $ and prices $S_{\rm u},A_{\rm u}$}}{463}{section.2145}% \contentsline {paragraph}{\tocparagraph {}{}{What this section proves and how to read it.}}{463}{section*.2146}% \contentsline {subsection}{\tocsubsection {}{28.1}{One-way replacements imposing twelve projected pairs}}{463}{subsection.2147}% \contentsline {paragraph}{\tocparagraph {}{}{Queries and records.}}{463}{section*.2148}% \contentsline {paragraph}{\tocparagraph {}{}{The repair.}}{465}{section*.2152}% \contentsline {paragraph}{\tocparagraph {}{}{The repair formula.}}{465}{section*.2153}% \contentsline {subsection}{\tocsubsection {}{28.2}{Star terms in the one-way replacements}}{466}{subsection.2155}% \contentsline {paragraph}{\tocparagraph {}{}{Setting.}}{467}{section*.2156}% \contentsline {subsection}{\tocsubsection {}{28.3}{Replacements keeping the old cross edges}}{471}{subsection.2165}% \contentsline {paragraph}{\tocparagraph {}{}{Forest records.}}{471}{section*.2166}% \contentsline {paragraph}{\tocparagraph {}{}{Dense laws.}}{473}{section*.2172}% \contentsline {paragraph}{\tocparagraph {}{}{The LE mixture.}}{476}{section*.2180}% \contentsline {paragraph}{\tocparagraph {}{}{The formula.}}{477}{section*.2183}% \contentsline {subsection}{\tocsubsection {}{28.4}{Complete six-query refinements used in the final closing}}{477}{subsection.2185}% \contentsline {subsection}{\tocsubsection {}{28.5}{A bound at a band start holds at every larger prime in the band}}{482}{subsection.2194}% \contentsline {paragraph}{\tocparagraph {}{}{Evaluation points.}}{485}{section*.2208}% \contentsline {subsection}{\tocsubsection {}{28.6}{(CP4) for upper atoms with prices $S_{\rm u},A_{\rm u}$}}{486}{subsection.2217}% \contentsline {paragraph}{\tocparagraph {}{}{The upper prices in the closing.}}{489}{section*.2230}% \contentsline {paragraph}{\tocparagraph {}{}{Consequences and what to read next.}}{489}{section*.2231}% \contentsline {paragraph}{\tocparagraph {}{}{Hypotheses verified in this section: (CP4) and (R5) for upper atoms.}}{490}{section*.2232}% \contentsline {section}{\tocsection {}{29}{Large primes $p\ge 2^{512}$ and the external index}}{490}{section.2233}% \contentsline {paragraph}{\tocparagraph {}{}{What this section proves and how to read it.}}{490}{section*.2234}% \contentsline {subsection}{\tocsubsection {}{29.1}{The reference law at one large prime}}{490}{subsection.2235}% \contentsline {subsection}{\tocsubsection {}{29.2}{Mixing at the tail primes}}{492}{subsection.2244}% \contentsline {subsection}{\tocsubsection {}{29.3}{Comparison prices $O(p^{-3/2+2a})$ at large primes}}{492}{subsection.2250}% \contentsline {subsection}{\tocsubsection {}{29.4}{The external index by exact conductor}}{494}{subsection.2260}% \contentsline {subsection}{\tocsubsection {}{29.5}{Evaluating $R_I$, $J$ and $W$}}{497}{subsection.2268}% \contentsline {paragraph}{\tocparagraph {}{}{Consequences and what to read next.}}{498}{section*.2276}% \contentsline {paragraph}{\tocparagraph {}{}{Hypotheses verified in this section.}}{498}{section*.2277}% \contentsline {section}{\tocsection {}{30}{Baseline closing: $\Theta <1$ with $\theta =1$}}{498}{section.2278}% \contentsline {paragraph}{\tocparagraph {}{}{What this section proves and how to read it.}}{498}{section*.2279}% \contentsline {subsection}{\tocsubsection {}{30.1}{Definitions of $L_0,S,A,D,\mathcal E,T,R_I,J,W,m$ (baseline)}}{499}{subsection.2280}% \contentsline {subsection}{\tocsubsection {}{30.2}{Outward-interval evaluation: $\Theta <0.99999999997327$}}{504}{subsection.2305}% \contentsline {paragraph}{\tocparagraph {}{}{How the certificate evaluates $\Theta $.}}{505}{section*.2308}% \contentsline {subsection}{\tocsubsection {}{30.3}{Proof of the baseline ($\theta =1$) by Theorem\nonbreakingspace C}}{505}{subsection.2309}% \contentsline {paragraph}{\tocparagraph {}{}{Consequences and what to read next.}}{505}{section*.2310}% \contentsline {paragraph}{\tocparagraph {}{}{Hypotheses verified in this section.}}{506}{section*.2311}% \contentsline {section}{\tocsection {}{31}{Stronger density estimates: multilinear bounds and a new prefix law}}{506}{section.2312}% \contentsline {paragraph}{\tocparagraph {}{}{What this section proves and how to read it.}}{506}{section*.2313}% \contentsline {subsection}{\tocsubsection {}{31.1}{Uniform convexity and mixtures on a finite alphabet}}{506}{subsection.2316}% \contentsline {subsection}{\tocsubsection {}{31.2}{A pair moment and independent draws from a digit clique}}{507}{subsection.2322}% \contentsline {subsection}{\tocsubsection {}{31.3}{The replacement prefix and its dominators}}{509}{subsection.2336}% \contentsline {section}{\tocsection {}{32}{Induction with density exponent $\vartheta >1$}}{511}{section.2345}% \contentsline {paragraph}{\tocparagraph {}{}{What this section proves and how to read it.}}{511}{section*.2346}% \contentsline {subsection}{\tocsubsection {}{32.1}{Multilinear bounds for the laws used in the induction}}{511}{subsection.2348}% \contentsline {subsection}{\tocsubsection {}{32.2}{Concentrated packets: pinning rare constant labels}}{514}{subsection.2358}% \contentsline {subsection}{\tocsubsection {}{32.3}{Sharp estimates with coupled positive spectators}}{516}{subsection.2367}% \contentsline {subsection}{\tocsubsection {}{32.4}{Restoration with an $L^2$ orbit bound}}{519}{subsection.2372}% \contentsline {subsection}{\tocsubsection {}{32.5}{Uniform errors at a least counterexample}}{520}{subsection.2376}% \contentsline {section}{\tocsection {}{33}{Improved closing: $\Theta <0.999999771$ with $\vartheta =\frac {1014587}{1000000}$}}{521}{section.2381}% \contentsline {subsection}{\tocsubsection {}{33.1}{Accounting for the normalizing factor $Z_i^{-1}$}}{521}{subsection.2382}% \contentsline {subsection}{\tocsubsection {}{33.2}{The selected laws and common assignments}}{523}{subsection.2390}% \contentsline {subsection}{\tocsubsection {}{33.3}{The joint closing number}}{524}{subsection.2392}% \contentsline {section}{\tocsection {}{34}{How the construction developed}}{525}{section.2397}% \contentsline {paragraph}{\tocparagraph {}{}{What this section is for (not used in the proof).}}{525}{section*.2398}% \contentsline {subsection}{\tocsubsection {}{34.1}{The checkpoints}}{526}{subsection.2399}% \contentsline {subsection}{\tocsubsection {}{34.2}{The $216$-slot starting point}}{527}{subsection.2401}% \contentsline {subsection}{\tocsubsection {}{34.3}{Sparse laws, single edges and best cuts}}{528}{subsection.2403}% \contentsline {subsection}{\tocsubsection {}{34.4}{Two layers, six queries and the October 18 record}}{528}{subsection.2404}% \contentsline {subsection}{\tocsubsection {}{34.5}{Blocks and the $72$-slot form}}{528}{subsection.2405}% \contentsline {subsection}{\tocsubsection {}{34.6}{Exact actual laws, signed blocks and positive roots}}{529}{subsection.2407}% \contentsline {subsection}{\tocsubsection {}{34.7}{The October 29 local refinements}}{529}{subsection.2408}% \contentsline {subsection}{\tocsubsection {}{34.8}{What the successive versions showed}}{530}{subsection.2409}% \contentsline {section}{\tocsection {}{35}{Obstructions, limits and pitfalls}}{530}{section.2410}% \contentsline {paragraph}{\tocparagraph {}{}{What this section is for (not used in the proof).}}{530}{section*.2411}% \contentsline {subsection}{\tocsubsection {}{35.1}{The crude bound exceeds $1$ (distinct from $\Theta <1$)}}{530}{subsection.2412}% \contentsline {subsection}{\tocsubsection {}{35.2}{No positive order at the reserved cut}}{531}{subsection.2415}% \contentsline {subsection}{\tocsubsection {}{35.3}{Pairing and signed blocks: norms against envelopes}}{531}{subsection.2418}% \contentsline {subsection}{\tocsubsection {}{35.4}{The walls of the prefix at primes $p\equiv 1\pmod 4$}}{533}{subsection.2425}% \contentsline {subsection}{\tocsubsection {}{35.5}{Why class one is a prefix}}{533}{subsection.2428}% \contentsline {subsection}{\tocsubsection {}{35.6}{The root law: forced support and forced norm}}{534}{subsection.2429}% \contentsline {subsection}{\tocsubsection {}{35.7}{Why twelve queries do not help}}{534}{subsection.2432}% \contentsline {subsection}{\tocsubsection {}{35.8}{Obstruction polynomials of the singleton recurrence}}{535}{subsection.2435}% \contentsline {subsection}{\tocsubsection {}{35.9}{Limits of the method}}{537}{subsection.2442}% \contentsline {subsection}{\tocsubsection {}{35.10}{Tested and not pursued}}{538}{subsection.2443}% \contentsline {paragraph}{\tocparagraph {}{}{Instructive choices in the spectral method.}}{540}{section*.2446}% \contentsline {subsection}{\tocsubsection {}{35.11}{Errors to avoid when checking or extending the proof}}{541}{subsection.2447}% \contentsline {subsection}{\tocsubsection {}{35.12}{Scope of the reviews}}{542}{subsection.2448}% \contentsline {paragraph}{\tocparagraph {}{}{Consequences.}}{544}{section*.2449}% \contentsline {section}{\tocsection {Appendix}{A}{External inputs}}{544}{appendix.2450}% \contentsline {paragraph}{\tocparagraph {}{}{What this appendix proves and how to read it.}}{544}{section*.2451}% \contentsline {subsection}{\tocsubsection {}{A.1}{The characters of $\mathrm {GL}_2(\mathbb F_q)$}}{544}{subsection.2452}% \contentsline {subsection}{\tocsubsection {}{A.2}{$\ell $-adic sheaves on curves}}{545}{subsection.2459}% \contentsline {subsection}{\tocsubsection {}{A.3}{A modular coefficient}}{548}{subsection.2480}% \contentsline {subsection}{\tocsubsection {}{A.4}{Sources of the standard inputs}}{549}{subsection.2485}% \contentsline {paragraph}{\tocparagraph {}{}{Consequences and what to read next.}}{550}{section*.2486}% \contentsline {section}{\tocsection {Appendix}{B}{Peyre's tensorization in finite form}}{550}{appendix.2487}% \contentsline {paragraph}{\tocparagraph {}{}{What this appendix proves and how to read it.}}{550}{section*.2488}% \contentsline {subsection}{\tocsubsection {}{B.1}{Conventions}}{551}{subsection.2494}% \contentsline {subsection}{\tocsubsection {}{B.2}{Elementary facts}}{551}{subsection.2498}% \contentsline {subsection}{\tocsubsection {}{B.3}{One variable against a list}}{552}{subsection.2504}% \contentsline {subsection}{\tocsubsection {}{B.4}{Positive weights}}{553}{subsection.2510}% \contentsline {subsection}{\tocsubsection {}{B.5}{Proof of the tensorization theorem}}{554}{subsection.2515}% \contentsline {subsection}{\tocsubsection {}{B.6}{Remarks}}{555}{subsection.2521}% \contentsline {paragraph}{\tocparagraph {}{}{Consequences and what to read next.}}{556}{section*.2526}% \contentsline {section}{\tocsection {Appendix}{C}{The actual-square kernel for cutoffs up to $N^{1/20}$}}{556}{appendix.2527}% \contentsline {paragraph}{\tocparagraph {}{}{What this appendix proves and how to read it.}}{556}{section*.2528}% \contentsline {paragraph}{\tocparagraph {}{}{Conventions.}}{556}{section*.2529}% \contentsline {subsection}{\tocsubsection {}{C.1}{The two kernels}}{556}{subsection.2530}% \contentsline {paragraph}{\tocparagraph {}{}{How the kernels are matched.}}{558}{section*.2539}% \contentsline {subsection}{\tocsubsection {}{C.2}{Weyl's inequality with even denominators}}{558}{subsection.2542}% \contentsline {subsection}{\tocsubsection {}{C.3}{Arcs}}{559}{subsection.2545}% \contentsline {subsection}{\tocsubsection {}{C.4}{Local factors and the arithmetic coefficient}}{560}{subsection.2552}% \contentsline {subsection}{\tocsubsection {}{C.5}{The uniform approximation and the kernel estimate}}{561}{subsection.2559}% \contentsline {subsection}{\tocsubsection {}{C.6}{Nonunit differences}}{562}{subsection.2562}% \contentsline {subsection}{\tocsubsection {}{C.7}{The range of the method}}{563}{subsection.2569}% \contentsline {paragraph}{\tocparagraph {}{}{Consequences and what to read next.}}{563}{section*.2572}% \contentsline {section}{\tocsection {Appendix}{D}{Certificates: model, scope, and the evaluation of $\Theta $}}{563}{appendix.2573}% \contentsline {paragraph}{\tocparagraph {}{}{What this appendix proves and how to read it.}}{563}{section*.2574}% \contentsline {subsection}{\tocsubsection {}{D.1}{The certificate model and its scope}}{564}{subsection.2575}% \contentsline {paragraph}{\tocparagraph {}{}{Arithmetic.}}{564}{section*.2578}% \contentsline {paragraph}{\tocparagraph {}{}{Evaluation at endpoints.}}{564}{section*.2579}% \contentsline {paragraph}{\tocparagraph {}{}{Scope.}}{564}{section*.2580}% \contentsline {subsection}{\tocsubsection {}{D.2}{The baseline verifier chain}}{565}{subsection.2581}% \contentsline {paragraph}{\tocparagraph {}{}{How it is run.}}{565}{section*.2582}% \contentsline {paragraph}{\tocparagraph {}{}{The selected refinements.}}{565}{section*.2583}% \contentsline {paragraph}{\tocparagraph {}{}{What the final verifier re-evaluates.}}{566}{section*.2584}% \contentsline {paragraph}{\tocparagraph {}{}{What it authenticates.}}{566}{section*.2585}% \contentsline {paragraph}{\tocparagraph {}{}{What it checks that the proof does not use.}}{566}{section*.2586}% \contentsline {paragraph}{\tocparagraph {}{}{Abbreviations.}}{566}{section*.2587}% \contentsline {paragraph}{\tocparagraph {}{}{Inherited formulas and selected evaluations.}}{567}{section*.2588}% \contentsline {paragraph}{\tocparagraph {}{}{The certificates of the text.}}{572}{section*.2589}% \contentsline {subsection}{\tocsubsection {}{D.3}{Checks for the local refinements of 29 October}}{576}{thmt@dummyctr.2631}% \contentsline {subsection}{\tocsubsection {}{D.4}{How the certificate evaluates $\Theta $}}{577}{subsection.2637}% \contentsline {subsection}{\tocsubsection {}{D.5}{What the earlier verifiers contribute}}{579}{subsection.2649}% \contentsline {subsection}{\tocsubsection {}{D.6}{The archive and the earlier checkpoints}}{580}{subsection.2653}% \contentsline {paragraph}{\tocparagraph {}{}{Consequences and what to read next.}}{583}{section*.2657}% \contentsline {section}{\tocsection {Appendix}{E}{Design data, prices and witness tables}}{583}{appendix.2658}% \contentsline {paragraph}{\tocparagraph {}{}{What this appendix is for (baseline tables only).}}{583}{section*.2659}% \contentsline {paragraph}{\tocparagraph {}{}{Conventions.}}{584}{section*.2660}% \contentsline {subsection}{\tocsubsection {}{E.1}{The parameters}}{584}{subsection.2661}% \contentsline {subsection}{\tocsubsection {}{E.2}{The middle pieces}}{584}{subsection.2662}% \contentsline {paragraph}{\tocparagraph {}{}{The histogram of the exact blocks.}}{586}{section*.2663}% \contentsline {paragraph}{\tocparagraph {}{}{Completion weights and piece values.}}{586}{section*.2664}% \contentsline {paragraph}{\tocparagraph {}{}{The caps of the reference.}}{588}{section*.2665}% \contentsline {subsection}{\tocsubsection {}{E.3}{Middle prices}}{589}{subsection.2666}% \contentsline {subsection}{\tocsubsection {}{E.4}{The sides of the matching envelopes}}{591}{subsection.2667}% \contentsline {subsection}{\tocsubsection {}{E.5}{The upper bands}}{592}{subsection.2668}% \contentsline {subsection}{\tocsubsection {}{E.6}{Envelope witnesses}}{594}{subsection.2669}% \contentsline {paragraph}{\tocparagraph {}{}{Constants.}}{594}{section*.2670}% \contentsline {paragraph}{\tocparagraph {}{}{The portfolio.}}{594}{section*.2671}% \contentsline {paragraph}{\tocparagraph {}{}{The pair witnesses.}}{595}{section*.2672}% \contentsline {subsection}{\tocsubsection {}{E.7}{Spectral grids and analytic slacks}}{595}{subsection.2673}% \contentsline {paragraph}{\tocparagraph {}{}{The twelve-label grids.}}{595}{section*.2674}% \contentsline {paragraph}{\tocparagraph {}{}{The grid of the cut L20.}}{596}{section*.2675}% \contentsline {paragraph}{\tocparagraph {}{}{The positive roots.}}{597}{section*.2676}% \contentsline {paragraph}{\tocparagraph {}{}{The completion-variance grid.}}{598}{section*.2677}% \contentsline {paragraph}{\tocparagraph {}{}{Analytic slacks.}}{598}{section*.2678}% \contentsline {paragraph}{\tocparagraph {}{}{Consequences and what to read next.}}{598}{section*.2679}% \contentsline {section}{\tocsection {Appendix}{F}{The exponent from the OpenAI parameters as displayed}}{599}{appendix.2680}% \contentsline {paragraph}{\tocparagraph {}{}{What this appendix proves and how to read it.}}{599}{section*.2681}% \contentsline {paragraph}{\tocparagraph {}{}{Result.}}{599}{section*.2682}% \contentsline {subsection}{\tocsubsection {}{F.1}{The fixed construction}}{600}{subsection.2687}% \contentsline {subsection}{\tocsubsection {}{F.2}{The prime threshold $P$}}{600}{subsection.2688}% \contentsline {subsection}{\tocsubsection {}{F.3}{Small modulus, good residues, and the exponent}}{600}{subsection.2691}% \contentsline {paragraph}{\tocparagraph {}{}{Consequences.}}{601}{section*.2692}% \contentsline {section}{\tocsection {Appendix}{}{Bibliography}}{601}{section*.2693}% \end{filecontents*} \makeatletter \AtBeginDocument{% \@ifundefined{HexagonAuxReady}{% \@ifundefined{r@thm:main}{% \newlabel{sec:intro}{{1}{9}{Introduction}{section.2}{}} \newlabel{sec:intro@cref}{{[section][1][]1}{[1][9][]9}{}{}{}} \newlabel{subsec:intro:statement}{{1.1}{9}{Statement and Context}{subsection.3}{}} \newlabel{subsec:intro:statement@cref}{{[subsection][1][1]1.1}{[1][9][]9}{}{}{}} \newlabel{thm:main}{{1.1}{9}{}{theorem.5}{}} \newlabel{thm:main@cref}{{[theorem][1][1]1.1}{[1][9][]9}{}{}{}} \newlabel{thm:baseline}{{1.2}{9}{The baseline bound, with density exponent $\vartheta =1$}{proposition.7}{}} \newlabel{thm:baseline@cref}{{[proposition][2][1]1.2}{[1][9][]9}{}{}{}} \newlabel{subsec:intro:method}{{1.2}{10}{Overview}{subsection.8}{}} \newlabel{subsec:intro:method@cref}{{[subsection][2][1]1.2}{[1][10][]10}{}{}{}} \newlabel{fig:intro:dependencies}{{1}{11}{Principal dependencies of the proof. External inputs feed the local tools of Part~IV; these build the laws of the construction in Part~V, which verify the hypotheses (CP0)--(CP8) of the comparison theorem of Part~III. The selected density moments and induction extend the analytic framework of Part~II; the normalized closing in \cref {sec:four-routes-closing} then gives \cref {thm:main}. The dashed arrow records finite arithmetic checks, whose scope is stated in \cref {subsec:intro:status} and \cref {app:certificates}. The parts are described in \cref {subsec:intro:outline}}{figure.9}{}} \newlabel{fig:intro:dependencies@cref}{{[figure][1][]1}{[1][10][]11}{}{}{}} \newlabel{eq:intro:closing}{{1.1}{12}{The six indices and the number $\Theta $}{equation.16}{}} \newlabel{eq:intro:closing@cref}{{[equation][1][1]1.1}{[1][12][]12}{}{}{}} \newlabel{subsec:intro:steps}{{1.3}{14}{The proof in five steps}{subsection.21}{}} \newlabel{subsec:intro:steps@cref}{{[subsection][3][1]1.3}{[1][14][]14}{}{}{}} \newlabel{subsec:intro:new}{{1.4}{15}{What is inherited from the OpenAI preprint, and what is new here}{subsection.22}{}} \newlabel{subsec:intro:new@cref}{{[subsection][4][1]1.4}{[1][15][]15}{}{}{}} \newlabel{subsec:intro:deligne}{{1.5}{19}{Where the Deligne bound enters}{subsection.25}{}} \newlabel{subsec:intro:deligne@cref}{{[subsection][5][1]1.5}{[1][18][]19}{}{}{}} \newlabel{subsec:intro:inequality}{{1.6}{21}{The closing inequality \texorpdfstring {$\Theta <1$}{Theta<1} in the baseline (\texorpdfstring {$\vartheta =1$}{vartheta=1})}{subsection.31}{}} \newlabel{subsec:intro:inequality@cref}{{[subsection][6][1]1.6}{[1][20][]21}{}{}{}} \newlabel{tab:intro:values}{{1}{22}{Baseline closing only ($\vartheta =1$, $a=\PushA $; this table does not prove \cref {thm:main}, whose improved values are in \cref {sec:four-routes-closing}): certified upper ($<$) and lower ($>$) bounds, rounded outward; $\ldots $ marks an exactly defined number (\cref {tab:closing-values} gives more digits)}{table.32}{}} \newlabel{tab:intro:values@cref}{{[table][1][]1}{[1][21][]22}{}{}{}} \newlabel{subsec:intro:status}{{1.7}{22}{Proof inputs and verification}{subsection.33}{}} \newlabel{subsec:intro:status@cref}{{[subsection][7][1]1.7}{[1][22][]22}{}{}{}} \newlabel{subsec:intro:glossary}{{1.8}{23}{Terminology used throughout}{subsection.34}{}} \newlabel{subsec:intro:glossary@cref}{{[subsection][8][1]1.8}{[1][23][]23}{}{}{}} \newlabel{subsec:intro:outline}{{1.9}{25}{Reading the proof}{subsection.35}{}} \newlabel{subsec:intro:outline@cref}{{[subsection][9][1]1.9}{[1][25][]25}{}{}{}} \newlabel{sec:mechanism}{{2}{26}{The whole argument with one query}{section.36}{}} \newlabel{sec:mechanism@cref}{{[section][2][]2}{[1][26][]26}{}{}{}} \newlabel{subsec:mech:chessboard}{{2.1}{26}{The \texorpdfstring {$72$}{72}-fold average and reflection positivity}{subsection.38}{}} \newlabel{subsec:mech:chessboard@cref}{{[subsection][1][2]2.1}{[1][26][]26}{}{}{}} \newlabel{eq:mech:one-cut}{{2.1}{27}{One cut, and folding repeatedly until all slots agree}{equation.41}{}} \newlabel{eq:mech:one-cut@cref}{{[equation][1][2]2.1}{[1][27][]27}{}{}{}} \newlabel{eq:mech:density}{{2.2}{28}{The slot array}{equation.44}{}} \newlabel{eq:mech:density@cref}{{[equation][2][2]2.2}{[1][27][]28}{}{}{}} \newlabel{subsec:mech:prices}{{2.2}{28}{Rescaling by square steps: the price of changing a local law}{subsection.46}{}} \newlabel{subsec:mech:prices@cref}{{[subsection][2][2]2.2}{[1][28][]28}{}{}{}} \newlabel{subsec:mech:index}{{2.3}{29}{One query and its external index \texorpdfstring {$(b,s)$}{(b,s)}}{subsection.51}{}} \newlabel{subsec:mech:index@cref}{{[subsection][3][2]2.3}{[1][29][]29}{}{}{}} \newlabel{eq:mech:mean}{{2.3}{29}{The mean identity}{equation.54}{}} \newlabel{eq:mech:mean@cref}{{[equation][3][2]2.3}{[1][29][]29}{}{}{}} \newlabel{eq:mech:signed}{{2.4}{29}{Coupling the two ends, and the signed combination $2P-T$}{equation.56}{}} \newlabel{eq:mech:signed@cref}{{[equation][4][2]2.4}{[1][29][]29}{}{}{}} \newlabel{eq:mech:RI}{{2.5}{30}{Decomposition by exact conductor}{equation.58}{}} \newlabel{eq:mech:RI@cref}{{[equation][5][2]2.5}{[1][30][]30}{}{}{}} \newlabel{eq:mech:index-support}{{2.6}{30}{The index-support lemma}{equation.60}{}} \newlabel{eq:mech:index-support@cref}{{[equation][6][2]2.6}{[1][30][]30}{}{}{}} \newlabel{subsec:mech:kernel}{{2.4}{30}{Where square-difference-freeness enters}{subsection.61}{}} \newlabel{subsec:mech:kernel@cref}{{[subsection][4][2]2.4}{[1][30][]30}{}{}{}} \newlabel{subsec:mech:one-query}{{2.5}{31}{One query: \texorpdfstring {$1\le \mathcal E+BR_I/2+W_1+o(1)$}{1 <= E+B R\_I/2+W\_1+o(1)} at a least counterexample}{subsection.62}{}} \newlabel{subsec:mech:one-query@cref}{{[subsection][5][2]2.5}{[1][31][]31}{}{}{}} \newlabel{prop:mech:one-query}{{2.1}{31}{One query}{proposition.64}{}} \newlabel{prop:mech:one-query@cref}{{[proposition][1][2]2.1}{[1][31][]31}{}{}{}} \newlabel{rem:mech:positive}{{2.2}{32}{A positive comparison law}{remark.68}{}} \newlabel{rem:mech:positive@cref}{{[remark][2][2]2.2}{[1][32][]32}{}{}{}} \newlabel{subsec:mech:budget}{{2.6}{32}{Why the sum of error bounds must be \texorpdfstring {$<1$}{<1}, and why one query fails}{subsection.69}{}} \newlabel{subsec:mech:budget@cref}{{[subsection][6][2]2.6}{[1][32][]32}{}{}{}} \newlabel{subsec:mech:crude}{{2.7}{33}{Why conditioning independent labels on a square difference does not 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\newlabel{subsec:walk:blocks@cref}{{[subsection][3][3]3.3}{[1][36][]36}{}{}{}} \newlabel{subsec:walk:queries}{{3.4}{37}{One query leaves an error term above \texorpdfstring {$1$}{1}: use six disjoint queries}{subsection.90}{}} \newlabel{subsec:walk:queries@cref}{{[subsection][4][3]3.4}{[1][37][]37}{}{}{}} \newlabel{subsec:walk:repair}{{3.5}{38}{Records that do not force a square difference: replace, delete, or dominate them}{subsection.94}{}} \newlabel{subsec:walk:repair@cref}{{[subsection][5][3]3.5}{[1][38][]38}{}{}{}} \newlabel{subsec:walk:bracket}{{3.6}{39}{The forcing law is not reflection positive: domination by \texorpdfstring {$2\times 2$}{2 x 2} blocks}{subsection.98}{}} \newlabel{subsec:walk:bracket@cref}{{[subsection][6][3]3.6}{[1][39][]39}{}{}{}} \newlabel{subsec:walk:accounting}{{3.7}{41}{The crude bound exceeds \texorpdfstring {$1$}{1}: five sharper inequalities}{subsection.104}{}} \newlabel{subsec:walk:accounting@cref}{{[subsection][7][3]3.7}{[1][40][]41}{}{}{}} \newlabel{subsec:walk:analytic}{{3.8}{42}{Six parameters of the analytic stage and the estimates they control}{subsection.112}{}} \newlabel{subsec:walk:analytic@cref}{{[subsection][8][3]3.8}{[1][42][]42}{}{}{}} \newlabel{subsec:walk:glance}{{3.9}{43}{From the local laws to the final closing}{subsection.119}{}} \newlabel{subsec:walk:glance@cref}{{[subsection][9][3]3.9}{[1][42][]43}{}{}{}} \newlabel{tab:walk:glance}{{3}{43}{The construction's interfaces and their final assembly}{table.120}{}} \newlabel{tab:walk:glance@cref}{{[table][3][]3}{[1][43][]43}{}{}{}} \newlabel{sec:notation}{{4}{43}{Preliminary lemmas: character sums, correlation, and monotone bounds}{section.121}{}} \newlabel{sec:notation@cref}{{[section][4][]4}{[1][43][]43}{}{}{}} \newlabel{subsec:notation:conventions}{{4.1}{43}{Finite probability spaces, operators, and correlation}{subsection.123}{}} \newlabel{subsec:notation:conventions@cref}{{[subsection][1][4]4.1}{[1][43][]43}{}{}{}} \newlabel{def:prelim:operators}{{4.1}{44}{Finite probability spaces and operator order}{definition.125}{}} \newlabel{def:prelim:operators@cref}{{[definition][1][4]4.1}{[1][43][]44}{}{}{}} \newlabel{def:split:notation}{{4.2}{44}{Mean, fluctuation and compression}{definition.128}{}} \newlabel{def:split:notation@cref}{{[definition][2][4]4.2}{[1][44][]44}{}{}{}} \newlabel{def:prelim:maxcorr}{{4.3}{44}{Maximal and conditional maximal correlation}{definition.130}{}} \newlabel{def:prelim:maxcorr@cref}{{[definition][3][4]4.3}{[1][44][]44}{}{}{}} \newlabel{def:prelim:angle}{{4.4}{45}{Friedrichs angle}{definition.132}{}} \newlabel{def:prelim:angle@cref}{{[definition][4][4]4.4}{[1][45][]45}{}{}{}} \newlabel{subsec:notation:symbols}{{4.2}{45}{Arithmetic notation, square classes, and index of symbols}{subsection.133}{}} \newlabel{subsec:notation:symbols@cref}{{[subsection][2][4]4.2}{[1][45][]45}{}{}{}} \newlabel{def:strict-square-class}{{4.5}{45}{Strict square classes}{definition.136}{}} \newlabel{def:strict-square-class@cref}{{[definition][5][4]4.5}{[1][45][]45}{}{}{}} \newlabel{def:nonvanishing-square-class}{{4.6}{45}{Nonvanishing square classes}{definition.138}{}} \newlabel{def:nonvanishing-square-class@cref}{{[definition][6][4]4.6}{[1][45][]45}{}{}{}} \gdef \LT@i {\LT@entry {1}{106.75662pt}\LT@entry {1}{347.27293pt}} \newlabel{eq:sq}{{4.1}{46}{The least square step}{equation.140}{}} \newlabel{eq:sq@cref}{{[equation][1][4]4.1}{[1][45][]46}{}{}{}} \newlabel{tab:notation}{{4}{46}{Principal symbols. 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\newlabel{subsec:notation:square-shift}{{4.4}{51}{The square shift and the Paley matrix}{subsection.158}{}} \newlabel{subsec:notation:square-shift@cref}{{[subsection][4][4]4.4}{[1][51][]51}{}{}{}} \newlabel{lem:square-shift}{{4.11}{51}{The square shift and the Paley matrix}{lemma.160}{}} \newlabel{lem:square-shift@cref}{{[lemma][11][4]4.11}{[1][51][]51}{}{}{}} \newlabel{subsec:notation:primes}{{4.5}{53}{Primes in the classes modulo four}{subsection.165}{}} \newlabel{subsec:notation:primes@cref}{{[subsection][5][4]4.5}{[1][53][]53}{}{}{}} \newlabel{thm:bmor}{{4.12}{53}{Bennett--Martin--O'Bryant--Rechnitzer {\cite [Theorem~1.2 and Table~1]{BMOR18}}}{theorem.167}{}} \newlabel{thm:bmor@cref}{{[theorem][12][4]4.12}{[1][53][]53}{}{}{}} \newlabel{subsec:notation:correlation}{{4.6}{53}{Two correlation inequalities (Peyre and Kassabov)}{subsection.168}{}} \newlabel{subsec:notation:correlation@cref}{{[subsection][6][4]4.6}{[1][53][]53}{}{}{}} \newlabel{thm:peyre-finite}{{4.13}{53}{Peyre's 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\newlabel{thm:kassabov@cref}{{[theorem][16][4]4.16}{[1][54][]54}{}{}{}} \newlabel{subsec:notation:majorants}{{4.7}{55}{Monotone majorants: a bound at the smallest prime implies the bound at every larger prime}{subsection.179}{}} \newlabel{subsec:notation:majorants@cref}{{[subsection][7][4]4.7}{[1][54][]55}{}{}{}} \newlabel{def:majorant}{{4.17}{55}{Admissible and small functions}{definition.181}{}} \newlabel{def:majorant@cref}{{[definition][17][4]4.17}{[1][55][]55}{}{}{}} \newlabel{lem:majorant}{{4.18}{55}{Admissible majorants}{lemma.183}{}} \newlabel{lem:majorant@cref}{{[lemma][18][4]4.18}{[1][55][]55}{}{}{}} \newlabel{rem:majorant-use}{{4.19}{56}{How the lemma is applied}{remark.194}{}} \newlabel{rem:majorant-use@cref}{{[remark][19][4]4.19}{[1][56][]56}{}{}{}} \newlabel{sec:positivity}{{5}{57}{Reflection positivity and a H\"older inequality for signed laws}{section.196}{}} \newlabel{sec:positivity@cref}{{[section][5][]5}{[1][57][]57}{}{}{}} \newlabel{subsec:pos:cuts}{{5.1}{58}{Cuts 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\newlabel{lem:commoncut@cref}{{[lemma][4][5]5.4}{[1][59][]59}{}{}{}} \newlabel{rem:cc:limits}{{5.5}{60}{Limits of the common-cut order}{remark.219}{}} \newlabel{rem:cc:limits@cref}{{[remark][5][5]5.5}{[1][60][]60}{}{}{}} \newlabel{subsec:pos:brackets}{{5.2}{60}{Controlling a law that is not reflection positive by two reflection-positive laws (\texorpdfstring {$2\times 2$}{2 x 2} blocks)}{subsection.222}{}} \newlabel{subsec:pos:brackets@cref}{{[subsection][2][5]5.2}{[1][60][]60}{}{}{}} \newlabel{lem:record:block-gram}{{5.6}{61}{Block-Gram calculus}{lemma.224}{}} \newlabel{lem:record:block-gram@cref}{{[lemma][6][5]5.6}{[1][61][]61}{}{}{}} \newlabel{subsec:pos:holder}{{5.3}{61}{From one cut to all slots: the H\"older inequality}{subsection.229}{}} \newlabel{subsec:pos:holder@cref}{{[subsection][3][5]5.3}{[1][61][]61}{}{}{}} \newlabel{def:sorting}{{5.7}{62}{Folds; sorting sequences}{definition.231}{}} \newlabel{def:sorting@cref}{{[definition][7][5]5.7}{[1][62][]62}{}{}{}} \newlabel{lem:holder:one-cut}{{5.8}{62}{Cauchy--Schwarz at one cut}{lemma.233}{}} \newlabel{lem:holder:one-cut@cref}{{[lemma][8][5]5.8}{[1][62][]62}{}{}{}} \newlabel{eq:cs-cut}{{5.3}{62}{Cauchy--Schwarz at one cut}{equation.234}{}} \newlabel{eq:cs-cut@cref}{{[equation][3][5]5.3}{[1][62][]62}{}{}{}} \newlabel{thm:holder}{{5.9}{62}{Signed H\"older inequality}{theorem.236}{}} \newlabel{thm:holder@cref}{{[theorem][9][5]5.9}{[1][62][]62}{}{}{}} \newlabel{cor:seminorm}{{5.10}{62}{Seminorm}{corollary.238}{}} \newlabel{cor:seminorm@cref}{{[corollary][10][5]5.10}{[1][62][]62}{}{}{}} \newlabel{rem:cc:mixed}{{5.11}{62}{Domination at one cut}{remark.240}{}} \newlabel{rem:cc:mixed@cref}{{[remark][11][5]5.11}{[1][62][]62}{}{}{}} \newlabel{subsec:slot-array}{{5.4}{63}{The \texorpdfstring {$72$}{72} slots \texorpdfstring {$(\Z /6\Z )^2\times \{0,1\}$}{(Z/6Z)\textasciicircum 2 x \{0,1\}}, their symmetries, and the six queries}{subsection.241}{}} \newlabel{subsec:slot-array@cref}{{[subsection][4][5]5.4}{[1][63][]63}{}{}{}} \newlabel{def:slot-array}{{5.12}{63}{Reflection coordinates; the slot array}{definition.243}{}} \newlabel{def:slot-array@cref}{{[definition][12][5]5.12}{[1][63][]63}{}{}{}} \newlabel{lem:slot-array}{{5.13}{63}{The slot array}{lemma.250}{}} \newlabel{lem:slot-array@cref}{{[lemma][13][5]5.13}{[1][63][]63}{}{}{}} \newlabel{rem:slot-array-instances}{{5.14}{66}{}{remark.261}{}} \newlabel{rem:slot-array-instances@cref}{{[remark][14][5]5.14}{[1][66][]66}{}{}{}} \newlabel{subsec:pos:invariance}{{5.5}{66}{Square-affine invariance}{subsection.262}{}} \newlabel{subsec:pos:invariance@cref}{{[subsection][5][5]5.5}{[1][66][]66}{}{}{}} \newlabel{def:map:invariance}{{5.15}{66}{Square-affine invariance and pair law}{definition.264}{}} \newlabel{def:map:invariance@cref}{{[definition][15][5]5.15}{[1][66][]66}{}{}{}} \newlabel{lem:marginals}{{5.16}{66}{Marginals and pair laws}{lemma.266}{}} \newlabel{lem:marginals@cref}{{[lemma][16][5]5.16}{[1][66][]66}{}{}{}} \newlabel{it:marg:closure}{{{{\textup {(1)}}}}{66}{Marginals and pair laws}{Item.267}{}} \newlabel{it:marg:closure@cref}{{[enumi][1][]{{\textup {(1)}}}}{[1][66][]66}{}{}{}} \newlabel{it:marg:one}{{{{\textup {(2)}}}}{67}{Marginals and pair laws}{Item.268}{}} \newlabel{it:marg:one@cref}{{[enumi][2][]{{\textup {(2)}}}}{[1][67][]67}{}{}{}} \newlabel{it:marg:pair}{{{{\textup {(3)}}}}{67}{Marginals and pair laws}{Item.269}{}} \newlabel{it:marg:pair@cref}{{[enumi][3][]{{\textup {(3)}}}}{[1][67][]67}{}{}{}} \newlabel{subsec:pos:products}{{5.6}{67}{Independent atoms: product laws and \texorpdfstring {$\alpha ^{72}\le Y$}{alpha\textasciicircum 72 <= Y}}{subsection.270}{}} \newlabel{subsec:pos:products@cref}{{[subsection][6][5]5.6}{[1][67][]67}{}{}{}} \newlabel{lem:record:holder}{{5.17}{67}{Signed H\"older inequality, mean and averaging}{lemma.272}{}} \newlabel{lem:record:holder@cref}{{[lemma][17][5]5.17}{[1][67][]67}{}{}{}} \newlabel{sec:lifts}{{6}{68}{The functional \texorpdfstring {$Y$}{Y}: Fourier truncation and estimates preserving the density}{section.279}{}} \newlabel{sec:lifts@cref}{{[section][6][]6}{[1][68][]68}{}{}{}} \newlabel{subsec:lifts:functional}{{6.1}{69}{Definition of the lift \texorpdfstring {$F_A$}{F\_A} and the functional \texorpdfstring {$Y(\Lsc ,A)$}{Y(L,A)}}{subsection.281}{}} \newlabel{subsec:lifts:functional@cref}{{[subsection][1][6]6.1}{[1][69][]69}{}{}{}} \newlabel{def:record:functional}{{6.1}{69}{The functional}{definition.283}{}} \newlabel{def:record:functional@cref}{{[definition][1][6]6.1}{[1][69][]69}{}{}{}} \newlabel{subsec:lifts:reference}{{6.2}{70}{Assumptions (R1)--(R5) on the per-atom laws (proved in Part~V)}{subsection.291}{}} \newlabel{subsec:lifts:reference@cref}{{[subsection][2][6]6.2}{[1][70][]70}{}{}{}} \newlabel{hyp:record:reference}{{6.2}{70}{Reference atom laws}{hypothesis.293}{}} \newlabel{hyp:record:reference@cref}{{[hypothesis][2][6]6.2}{[1][70][]70}{}{}{}} \newlabel{it:record:R1}{{{{(R1)}}}{70}{Reference atom laws}{Item.294}{}} \newlabel{it:record:R1@cref}{{[enumi][1][]{{(R1)}}}{[1][70][]70}{}{}{}} \newlabel{it:record:R2}{{{{(R2)}}}{70}{Reference atom laws}{Item.295}{}} \newlabel{it:record:R2@cref}{{[enumi][2][]{{(R2)}}}{[1][70][]70}{}{}{}} \newlabel{it:record:R3}{{{{(R3)}}}{70}{Reference atom laws}{Item.296}{}} \newlabel{it:record:R3@cref}{{[enumi][3][]{{(R3)}}}{[1][70][]70}{}{}{}} \newlabel{it:record:R4}{{{{(R4)}}}{70}{Reference atom laws}{Item.297}{}} \newlabel{it:record:R4@cref}{{[enumi][4][]{{(R4)}}}{[1][70][]70}{}{}{}} \newlabel{it:record:R5}{{{{(R5)}}}{71}{Reference atom laws}{Item.298}{}} \newlabel{it:record:R5@cref}{{[enumi][5][]{{(R5)}}}{[1][70][]71}{}{}{}} \newlabel{subsec:lifts:index}{{6.3}{71}{Averaging a lift over intervals and residues is exact}{subsection.299}{}} \newlabel{subsec:lifts:index@cref}{{[subsection][3][6]6.3}{[1][71][]71}{}{}{}} \newlabel{lem:twointerval}{{6.3}{71}{Index averages}{lemma.301}{}} \newlabel{lem:twointerval@cref}{{[lemma][3][6]6.3}{[1][71][]71}{}{}{}} \newlabel{it:ti:intervals}{{{{\textup {(i)}}}}{71}{Index averages}{Item.302}{}} \newlabel{it:ti:intervals@cref}{{[enumi][1][]{{\textup {(i)}}}}{[1][71][]71}{}{}{}} \newlabel{it:ti:residues}{{{{\textup {(ii)}}}}{71}{Index averages}{Item.303}{}} \newlabel{it:ti:residues@cref}{{[enumi][2][]{{\textup {(ii)}}}}{[1][71][]71}{}{}{}} \newlabel{it:ti:mean}{{{{\textup {(iii)}}}}{71}{Index averages}{Item.304}{}} \newlabel{it:ti:mean@cref}{{[enumi][3][]{{\textup {(iii)}}}}{[1][71][]71}{}{}{}} \newlabel{subsec:lifts:moments}{{6.4}{72}{\texorpdfstring {$L^{2r}$}{L\textasciicircum (2r)} bounds for lifts, linear in the density}{subsection.305}{}} \newlabel{subsec:lifts:moments@cref}{{[subsection][4][6]6.4}{[1][72][]72}{}{}{}} \newlabel{lem:lift:conditional-squares}{{6.4}{72}{Gram bound and conditional square sums}{lemma.307}{}} \newlabel{lem:lift:conditional-squares@cref}{{[lemma][4][6]6.4}{[1][72][]72}{}{}{}} \newlabel{eq:cond-square}{{6.1}{72}{Gram bound and conditional square sums}{equation.310}{}} \newlabel{eq:cond-square@cref}{{[equation][1][6]6.1}{[1][72][]72}{}{}{}} \newlabel{lem:sqfun-rec}{{6.5}{73}{Square-function recursion}{lemma.312}{}} \newlabel{lem:sqfun-rec@cref}{{[lemma][5][6]6.5}{[1][72][]73}{}{}{}} \newlabel{lem:lift:decoupling}{{6.6}{73}{Decoupling by coordinate colours}{lemma.314}{}} \newlabel{lem:lift:decoupling@cref}{{[lemma][6][6]6.6}{[1][73][]73}{}{}{}} \newlabel{lem:record:lift-moments}{{6.7}{74}{Moments that retain the $\ell ^2$ mass}{lemma.316}{}} \newlabel{lem:record:lift-moments@cref}{{[lemma][7][6]6.7}{[1][74][]74}{}{}{}} \newlabel{eq:record:Echi}{{6.2}{74}{\texorpdfstring {$L^{2r}$}{L\textasciicircum (2r)} bounds for lifts, linear in the density}{equation.320}{}} \newlabel{eq:record:Echi@cref}{{[equation][2][6]6.2}{[1][74][]74}{}{}{}} \newlabel{lem:record:conditional-moments}{{6.8}{75}{Conditional moments}{corollary.322}{}} \newlabel{lem:record:conditional-moments@cref}{{[corollary][8][6]6.8}{[1][75][]75}{}{}{}} \newlabel{rem:lift:fibres}{{6.9}{75}{Averages and suprema over fibres}{remark.324}{}} \newlabel{rem:lift:fibres@cref}{{[remark][9][6]6.9}{[1][75][]75}{}{}{}} \newlabel{subsec:lifts:sectors}{{6.5}{75}{Tensor products preserve exact Fourier support}{subsection.325}{}} \newlabel{subsec:lifts:sectors@cref}{{[subsection][5][6]6.5}{[1][75][]75}{}{}{}} \newlabel{lem:sector}{{6.10}{76}{Sector lemma}{lemma.328}{}} \newlabel{lem:sector@cref}{{[lemma][10][6]6.10}{[1][76][]76}{}{}{}} \newlabel{rem:sector-uses}{{6.11}{78}{How the sector lemma is used}{remark.338}{}} \newlabel{rem:sector-uses@cref}{{[remark][11][6]6.11}{[1][78][]78}{}{}{}} \newlabel{rem:signed-mixture-sectors}{{6.12}{79}{Signed mixtures of products}{remark.340}{}} \newlabel{rem:signed-mixture-sectors@cref}{{[remark][12][6]6.12}{[1][79][]79}{}{}{}} \newlabel{subsec:lifts:decay}{{6.6}{79}{Fourier terms of large conductor are damped at the mixing primes \texorpdfstring {$p\ge \Pfive $}{p >= P\_5}}{subsection.341}{}} \newlabel{subsec:lifts:decay@cref}{{[subsection][6][6]6.6}{[1][79][]79}{}{}{}} \newlabel{def:mixing}{{6.13}{79}{Conditional mixing}{definition.343}{}} \newlabel{def:mixing@cref}{{[definition][13][6]6.13}{[1][79][]79}{}{}{}} \newlabel{lem:mixture}{{6.14}{79}{Mixtures}{lemma.345}{}} \newlabel{lem:mixture@cref}{{[lemma][14][6]6.14}{[1][79][]79}{}{}{}} \newlabel{lem:record:prefix-conductor}{{6.15}{80}{Conductor decay with a finite prefix}{lemma.347}{}} \newlabel{lem:record:prefix-conductor@cref}{{[lemma][15][6]6.15}{[1][80][]80}{}{}{}} \newlabel{eq:pre:contraction}{{6.3}{80}{Fourier terms of large conductor are damped at the mixing primes \texorpdfstring {$p\ge \Pfive $}{p >= P\_5}}{equation.348}{}} \newlabel{eq:pre:contraction@cref}{{[equation][3][6]6.3}{[1][80][]80}{}{}{}} \newlabel{lem:tr:pairsupport}{{6.16}{81}{Decay by exact pair support}{lemma.350}{}} \newlabel{lem:tr:pairsupport@cref}{{[lemma][16][6]6.16}{[1][80][]81}{}{}{}} \newlabel{sec:kernel}{{7}{81}{Cancellation from square-difference-freeness: statement of the kernel estimate}{section.352}{}} \newlabel{sec:kernel@cref}{{[section][7][]7}{[1][81][]81}{}{}{}} \newlabel{def:kernel-notation}{{7.1}{81}{Kernel notation}{definition.355}{}} \newlabel{def:kernel-notation@cref}{{[definition][1][7]7.1}{[1][81][]81}{}{}{}} \newlabel{def:kernel-conditions}{{7.2}{82}{Kernel exponents}{definition.357}{}} \newlabel{def:kernel-conditions@cref}{{[definition][2][7]7.2}{[1][82][]82}{}{}{}} \newlabel{prop:record:kernel20}{{7.3}{82}{The actual-square kernel}{proposition.359}{}} \newlabel{prop:record:kernel20@cref}{{[proposition][3][7]7.3}{[1][82][]82}{}{}{}} \newlabel{eq:record:K20}{{7.1}{82}{The actual-square kernel}{equation.361}{}} \newlabel{eq:record:K20@cref}{{[equation][1][7]7.1}{[1][82][]82}{}{}{}} \newlabel{cor:kernel20}{{7.4}{82}{The kernel at $\beta =1/20$}{corollary.365}{}} \newlabel{cor:kernel20@cref}{{[corollary][4][7]7.4}{[1][82][]82}{}{}{}} \newlabel{sec:scale-comparison}{{8}{84}{Induction on the scale: reducing pinned averages to smaller instances}{section.370}{}} \newlabel{sec:scale-comparison@cref}{{[section][8][]8}{[1][84][]84}{}{}{}} \newlabel{subsec:scale:stage}{{8.1}{84}{Numerical exponents and the inequalities they must satisfy}{subsection.373}{}} \newlabel{subsec:scale:stage@cref}{{[subsection][1][8]8.1}{[1][84][]84}{}{}{}} \newlabel{def:record:analytic-stage}{{8.1}{84}{Analytic stage}{definition.375}{}} \newlabel{def:record:analytic-stage@cref}{{[definition][1][8]8.1}{[1][84][]84}{}{}{}} \newlabel{subsec:scale:fibres}{{8.2}{85}{Residue-class restriction and square-step rescaling}{subsection.384}{}} \newlabel{subsec:scale:fibres@cref}{{[subsection][2][8]8.2}{[1][85][]85}{}{}{}} \newlabel{eq:square-step}{{8.1}{85}{Residue-class restriction and square-step rescaling}{equation.385}{}} \newlabel{eq:square-step@cref}{{[equation][1][8]8.1}{[1][85][]85}{}{}{}} \newlabel{lem:record:fibre-scale}{{8.2}{85}{Exact fibres and the square-step comparison input}{lemma.387}{}} \newlabel{lem:record:fibre-scale@cref}{{[lemma][2][8]8.2}{[1][85][]85}{}{}{}} \newlabel{lem:scale-conditions}{{8.3}{87}{Scale conditions}{lemma.394}{}} \newlabel{lem:scale-conditions@cref}{{[lemma][3][8]8.3}{[1][87][]87}{}{}{}} \newlabel{subsec:scale:structured}{{8.3}{88}{Pinned averages at a least counterexample}{subsection.402}{}} \newlabel{subsec:scale:structured@cref}{{[subsection][3][8]8.3}{[1][88][]88}{}{}{}} \newlabel{def:record:counterexample}{{8.4}{88}{Least normalized counterexample}{definition.404}{}} \newlabel{def:record:counterexample@cref}{{[definition][4][8]8.4}{[1][88][]88}{}{}{}} \newlabel{def:record:structured-energy}{{8.5}{88}{Structured energies and prices}{definition.406}{}} \newlabel{def:record:structured-energy@cref}{{[definition][5][8]8.5}{[1][88][]88}{}{}{}} \newlabel{lem:record:density-dc}{{8.6}{88}{Averaged comparison with a density factor}{lemma.411}{}} \newlabel{lem:record:density-dc@cref}{{[lemma][6][8]8.6}{[1][88][]88}{}{}{}} \newlabel{prop:record:density-structured}{{8.7}{89}{Density-structured energy estimate}{proposition.413}{}} \newlabel{prop:record:density-structured@cref}{{[proposition][7][8]8.7}{[1][89][]89}{}{}{}} \newlabel{subsec:scale:folded}{{8.4}{90}{Differences of laws at one cut, and the order for applying bounds}{subsection.414}{}} \newlabel{subsec:scale:folded@cref}{{[subsection][4][8]8.4}{[1][90][]90}{}{}{}} \newlabel{lem:record:folded-energy}{{8.8}{90}{Folded energies}{lemma.416}{}} \newlabel{lem:record:folded-energy@cref}{{[lemma][8][8]8.8}{[1][90][]90}{}{}{}} \newlabel{eq:record:sharp}{{8.2}{90}{Folded energies}{equation.417}{}} \newlabel{eq:record:sharp@cref}{{[equation][2][8]8.2}{[1][90][]90}{}{}{}} \newlabel{def:admissible}{{8.9}{92}{Admissible laws}{definition.424}{}} \newlabel{def:admissible@cref}{{[definition][9][8]8.9}{[1][92][]92}{}{}{}} \newlabel{subsec:scale:cancellation}{{8.5}{93}{Forced pairs and very large pinnings are negligible}{subsection.429}{}} \newlabel{subsec:scale:cancellation@cref}{{[subsection][5][8]8.5}{[1][93][]93}{}{}{}} \newlabel{lem:record:density-can}{{8.10}{93}{Accepted-pair cancellation with a density factor}{lemma.431}{}} \newlabel{lem:record:density-can@cref}{{[lemma][10][8]8.10}{[1][93][]93}{}{}{}} \newlabel{lem:record:density-lp}{{8.11}{95}{Large products with a density factor}{lemma.435}{}} \newlabel{lem:record:density-lp@cref}{{[lemma][11][8]8.11}{[1][95][]95}{}{}{}} \newlabel{subsec:scale:induction}{{8.6}{95}{From \texorpdfstring {$\Theta <1$}{Theta<1} to \texorpdfstring {$s(N)\le CN^{1-a/71}$}{s(N) <= C N\textasciicircum (1-a/71)} (baseline induction)}{subsection.436}{}} \newlabel{subsec:scale:induction@cref}{{[subsection][6][8]8.6}{[1][95][]95}{}{}{}} \newlabel{thm:record:lineardensity}{{8.12}{95}{Linear-density induction}{theorem.438}{}} \newlabel{thm:record:lineardensity@cref}{{[theorem][12][8]8.12}{[1][95][]95}{}{}{}} \newlabel{rem:fixed-parameters}{{8.13}{96}{Fixed parameters}{remark.441}{}} \newlabel{rem:fixed-parameters@cref}{{[remark][13][8]8.13}{[1][96][]96}{}{}{}} \newlabel{rem:record:fibres}{{8.14}{97}{Empty and concentrated fibres}{remark.443}{}} \newlabel{rem:record:fibres@cref}{{[remark][14][8]8.14}{[1][97][]97}{}{}{}} \newlabel{rem:record:theta-ladder}{{8.15}{97}{The density exponent}{remark.449}{}} \newlabel{rem:record:theta-ladder@cref}{{[remark][15][8]8.15}{[1][97][]97}{}{}{}} \newlabel{sec:comparison-theorem}{{9}{97}{The comparison theorem: standing data, prices, and hypotheses}{section.451}{}} \newlabel{sec:comparison-theorem@cref}{{[section][9][]9}{[1][97][]97}{}{}{}} \newlabel{subsec:cp:prices}{{9.1}{98}{Standing data (CP0), prices, and conversion between exponents}{subsection.453}{}} \newlabel{subsec:cp:prices@cref}{{[subsection][1][9]9.1}{[1][98][]98}{}{}{}} \newlabel{def:cp0}{{9.1}{98}{(CP0) Standing data: slots, scales, queries, index}{definition.455}{}} \newlabel{def:cp0@cref}{{[definition][1][9]9.1}{[1][98][]98}{}{}{}} \newlabel{def:price}{{9.2}{99}{Prices}{definition.462}{}} \newlabel{def:price@cref}{{[definition][2][9]9.2}{[1][99][]99}{}{}{}} \newlabel{lem:record:repricing}{{9.3}{99}{Repricing}{lemma.467}{}} \newlabel{lem:record:repricing@cref}{{[lemma][3][9]9.3}{[1][99][]99}{}{}{}} \newlabel{cor:first-stage-repricing}{{9.4}{100}{The first stage at a larger exponent}{corollary.469}{}} \newlabel{cor:first-stage-repricing@cref}{{[corollary][4][9]9.4}{[1][100][]100}{}{}{}} \newlabel{subsec:cp:index}{{9.2}{100}{Queries and the random interval-and-residue index}{subsection.470}{}} \newlabel{subsec:cp:index@cref}{{[subsection][2][9]9.2}{[1][100][]100}{}{}{}} \newlabel{lem:func:unitsq}{{9.5}{100}{Unit squares}{lemma.472}{}} \newlabel{lem:func:unitsq@cref}{{[lemma][5][9]9.5}{[1][100][]100}{}{}{}} \newlabel{def:hyb:coupled}{{9.6}{101}{The coupled index}{definition.476}{}} \newlabel{def:hyb:coupled@cref}{{[definition][6][9]9.6}{[1][101][]101}{}{}{}} \newlabel{lem:hyb:moment}{{9.7}{102}{Conductor moment}{lemma.485}{}} \newlabel{lem:hyb:moment@cref}{{[lemma][7][9]9.7}{[1][102][]102}{}{}{}} \newlabel{eq:record:expansion}{{9.1}{102}{The signed index form}{equation.487}{}} \newlabel{eq:record:expansion@cref}{{[equation][1][9]9.1}{[1][102][]102}{}{}{}} \newlabel{rem:hyb:optimal}{{9.8}{102}{The choice of the coupling}{remark.489}{}} \newlabel{rem:hyb:optimal@cref}{{[remark][8][9]9.8}{[1][102][]102}{}{}{}} \newlabel{subsec:cp:hypotheses}{{9.3}{103}{Hypotheses (CP1)--(CP8) on the three laws}{subsection.490}{}} \newlabel{subsec:cp:hypotheses@cref}{{[subsection][3][9]9.3}{[1][102][]103}{}{}{}} \newlabel{def:cp:records}{{9.9}{103}{Records, diagonals and brackets}{definition.492}{}} \newlabel{def:cp:records@cref}{{[definition][9][9]9.9}{[1][103][]103}{}{}{}} \newlabel{def:cp1}{{9.10}{103}{(CP1) Reference}{definition.494}{}} \newlabel{def:cp1@cref}{{[definition][10][9]9.10}{[1][103][]103}{}{}{}} \newlabel{def:cp2}{{9.11}{103}{(CP2) First stage}{definition.496}{}} \newlabel{def:cp2@cref}{{[definition][11][9]9.11}{[1][103][]103}{}{}{}} \newlabel{rem:cp:tags}{{9.12}{103}{Tags}{remark.500}{}} \newlabel{rem:cp:tags@cref}{{[remark][12][9]9.12}{[1][103][]103}{}{}{}} \newlabel{def:cp3}{{9.13}{104}{(CP3) Gram bracket}{definition.502}{}} \newlabel{def:cp3@cref}{{[definition][13][9]9.13}{[1][104][]104}{}{}{}} \newlabel{def:record:comparison-law}{{9.14}{104}{(CP4) Comparison law}{definition.504}{}} \newlabel{def:record:comparison-law@cref}{{[definition][14][9]9.14}{[1][104][]104}{}{}{}} \newlabel{def:cp4}{{9.14}{104}{(CP4) Comparison law}{definition.504}{}} \newlabel{def:cp4@cref}{{[definition][14][9]9.14}{[1][104][]104}{}{}{}} \newlabel{rem:cp:charging}{{9.15}{105}{Charging rules}{remark.509}{}} \newlabel{rem:cp:charging@cref}{{[remark][15][9]9.15}{[1][105][]105}{}{}{}} \newlabel{def:cp5}{{9.16}{105}{(CP5) Class bounds}{definition.511}{}} \newlabel{def:cp5@cref}{{[definition][16][9]9.16}{[1][105][]105}{}{}{}} \newlabel{def:cp6}{{9.17}{106}{(CP6) Matching envelopes}{definition.513}{}} \newlabel{def:cp6@cref}{{[definition][17][9]9.17}{[1][106][]106}{}{}{}} \newlabel{def:cp7}{{9.18}{106}{(CP7) Mean energies}{definition.515}{}} \newlabel{def:cp7@cref}{{[definition][18][9]9.18}{[1][106][]106}{}{}{}} \newlabel{def:robust}{{9.19}{106}{Robust bounds}{definition.517}{}} \newlabel{def:robust@cref}{{[definition][19][9]9.19}{[1][106][]106}{}{}{}} \newlabel{def:cp8}{{9.20}{107}{(CP8) Admissibility, robustness, summability}{definition.521}{}} \newlabel{def:cp8@cref}{{[definition][20][9]9.20}{[1][107][]107}{}{}{}} \newlabel{subsec:cp:theorem}{{9.4}{107}{Theorem~C: if \texorpdfstring {$\Theta <1$}{Theta<1} then \texorpdfstring {$s(N)\le C'N^{1-a/(72-\theta )}$}{s(N) <= C' N\textasciicircum (1-a/(72-theta))}}{subsection.525}{}} \newlabel{subsec:cp:theorem@cref}{{[subsection][4][9]9.4}{[1][107][]107}{}{}{}} \newlabel{thm:comparison}{{9.21}{107}{Theorem~C. If $\Theta <1$ then $s(N)\le C'N^{1-a/(72-\theta )}$}{theorem.528}{}} \newlabel{thm:comparison@cref}{{[theorem][21][9]9.21}{[1][107][]107}{}{}{}} \newlabel{rem:cp:monotone}{{9.22}{108}{Monotonicity}{remark.530}{}} \newlabel{rem:cp:monotone@cref}{{[remark][22][9]9.22}{[1][108][]108}{}{}{}} \newlabel{rem:cp:reading}{{9.23}{108}{Reading the closing number}{remark.532}{}} \newlabel{rem:cp:reading@cref}{{[remark][23][9]9.23}{[1][108][]108}{}{}{}} \newlabel{sec:comparison-lemmas}{{10}{108}{Five estimates at a least counterexample}{section.534}{}} \newlabel{sec:comparison-lemmas@cref}{{[section][10][]10}{[1][108][]108}{}{}{}} \newlabel{lem:record:common-mean}{{10.1}{110}{Index-support lemma}{lemma.542}{}} \newlabel{lem:record:common-mean@cref}{{[lemma][1][10]10.1}{[1][110][]110}{}{}{}} \newlabel{eq:record:joint-gram}{{10.1}{110}{Index-support lemma}{equation.543}{}} \newlabel{eq:record:joint-gram@cref}{{[equation][1][10]10.1}{[1][110][]110}{}{}{}} \newlabel{eq:record:common-mean}{{10.2}{110}{Index-support lemma}{equation.545}{}} \newlabel{eq:record:common-mean@cref}{{[equation][2][10]10.2}{[1][110][]110}{}{}{}} \newlabel{lem:hyb:coupling}{{10.3}{111}{One-cut coupling inequality}{corollary.550}{}} \newlabel{lem:hyb:coupling@cref}{{[corollary][3][10]10.3}{[1][111][]111}{}{}{}} \newlabel{eq:hyb:coupling}{{10.3}{111}{One-cut coupling inequality}{equation.551}{}} \newlabel{eq:hyb:coupling@cref}{{[equation][3][10]10.3}{[1][111][]111}{}{}{}} \newlabel{cor:index-support-frame}{{10.4}{111}{The signed index form and the common mean}{corollary.553}{}} \newlabel{cor:index-support-frame@cref}{{[corollary][4][10]10.4}{[1][111][]111}{}{}{}} \newlabel{eq:index-support-frame}{{10.4}{112}{The signed index form and the common mean}{equation.557}{}} \newlabel{eq:index-support-frame@cref}{{[equation][4][10]10.4}{[1][111][]112}{}{}{}} \newlabel{lem:record:wrap-expansion}{{10.6}{112}{Expansion and wrap}{lemma.562}{}} \newlabel{lem:record:wrap-expansion@cref}{{[lemma][6][10]10.6}{[1][112][]112}{}{}{}} \newlabel{rem:wrap-coarse}{{10.7}{113}{The wrap uses the coarse interval factor}{remark.564}{}} \newlabel{rem:wrap-coarse@cref}{{[remark][7][10]10.7}{[1][113][]113}{}{}{}} \newlabel{lem:sharp-first}{{10.8}{114}{Tagged sharp-first expansion}{lemma.568}{}} \newlabel{lem:sharp-first@cref}{{[lemma][8][10]10.8}{[1][114][]114}{}{}{}} \newlabel{cor:two-cut-series}{{10.9}{115}{Two tags}{corollary.572}{}} \newlabel{cor:two-cut-series@cref}{{[corollary][9][10]10.9}{[1][115][]115}{}{}{}} \newlabel{lem:record:first-stage}{{10.10}{116}{First comparison}{lemma.574}{}} \newlabel{lem:record:first-stage@cref}{{[lemma][10][10]10.10}{[1][116][]116}{}{}{}} \newlabel{lem:bracket-energy}{{10.12}{116}{Energies under the bracket}{lemma.578}{}} \newlabel{lem:bracket-energy@cref}{{[lemma][12][10]10.12}{[1][116][]116}{}{}{}} \newlabel{lem:energy-toolkit}{{10.13}{117}{Energy toolkit: order, contraction and interpolation estimates}{lemma.580}{}} \newlabel{lem:energy-toolkit@cref}{{[lemma][13][10]10.13}{[1][117][]117}{}{}{}} \newlabel{it:record:E1}{{{{(E1)}}}{117}{Energy toolkit: order, contraction and interpolation estimates}{Item.581}{}} \newlabel{it:record:E1@cref}{{[enumi][1][]{{(E1)}}}{[1][117][]117}{}{}{}} \newlabel{it:record:E2}{{{{(E2)}}}{117}{Energy toolkit: order, contraction and interpolation estimates}{Item.582}{}} \newlabel{it:record:E2@cref}{{[enumi][2][]{{(E2)}}}{[1][117][]117}{}{}{}} \newlabel{it:record:E3}{{{{(E3)}}}{117}{Energy toolkit: order, contraction and interpolation estimates}{Item.583}{}} \newlabel{it:record:E3@cref}{{[enumi][3][]{{(E3)}}}{[1][117][]117}{}{}{}} \newlabel{it:record:P1}{{{{(P1)}}}{117}{Energy toolkit: order, contraction and interpolation estimates}{Item.584}{}} \newlabel{it:record:P1@cref}{{[enumi][1][]{{(P1)}}}{[1][117][]117}{}{}{}} \newlabel{it:record:P2}{{{{(P2)}}}{117}{Energy toolkit: order, contraction and interpolation estimates}{Item.585}{}} \newlabel{it:record:P2@cref}{{[enumi][2][]{{(P2)}}}{[1][117][]117}{}{}{}} \newlabel{it:record:P3}{{{{(P3)}}}{117}{Energy toolkit: order, contraction and interpolation estimates}{Item.586}{}} \newlabel{it:record:P3@cref}{{[enumi][3][]{{(P3)}}}{[1][117][]117}{}{}{}} \newlabel{it:record:P3b}{{(P3$'$)}{118}{Energy toolkit: order, contraction and interpolation estimates}{Item.586}{}} \newlabel{it:record:P3b@cref}{{[enumi][3][]{{(P3)}}}{[1][117][]118}{}{}{}} \newlabel{it:record:P4}{{{{(P4)}}}{118}{Energy toolkit: order, contraction and interpolation estimates}{Item.587}{}} \newlabel{it:record:P4@cref}{{[enumi][4][]{{(P4)}}}{[1][118][]118}{}{}{}} \newlabel{it:record:P5}{{{{(P5)}}}{118}{Energy toolkit: order, contraction and interpolation estimates}{Item.588}{}} \newlabel{it:record:P5@cref}{{[enumi][5][]{{(P5)}}}{[1][118][]118}{}{}{}} \newlabel{lem:record:record-expansion}{{10.14}{119}{Record expansion and complete polynomial}{lemma.592}{}} \newlabel{lem:record:record-expansion@cref}{{[lemma][14][10]10.14}{[1][119][]119}{}{}{}} \newlabel{rem:completion-subtraction}{{10.15}{121}{Completion and subtraction}{remark.599}{}} \newlabel{rem:completion-subtraction@cref}{{[remark][15][10]10.15}{[1][121][]121}{}{}{}} \newlabel{lem:record:variance-interface}{{10.16}{122}{Variance form at the reserved cut}{lemma.602}{}} \newlabel{lem:record:variance-interface@cref}{{[lemma][16][10]10.16}{[1][122][]122}{}{}{}} \newlabel{lem:envelope-energy}{{10.17}{123}{Envelope energies}{lemma.608}{}} \newlabel{lem:envelope-energy@cref}{{[lemma][17][10]10.17}{[1][123][]123}{}{}{}} \newlabel{lem:record:domination}{{10.18}{123}{The trivial mean credit and the bookkeeping of the closing}{remark.610}{}} \newlabel{lem:record:domination@cref}{{[remark][18][10]10.18}{[1][123][]123}{}{}{}} \newlabel{sec:comparison-proof}{{11}{124}{From the five estimates to Theorem~C}{section.612}{}} \newlabel{sec:comparison-proof@cref}{{[section][11][]11}{[1][124][]124}{}{}{}} \newlabel{subsec:cp:closing}{{11.1}{124}{At a least counterexample, \texorpdfstring {$1\le \Theta +o(1)$}{1 <= Theta+o(1)}}{subsection.614}{}} \newlabel{subsec:cp:closing@cref}{{[subsection][1][11]11.1}{[1][124][]124}{}{}{}} \newlabel{thm:record:criterion}{{11.1}{124}{Closing inequality}{lemma.616}{}} \newlabel{thm:record:criterion@cref}{{[lemma][1][11]11.1}{[1][124][]124}{}{}{}} \newlabel{eq:record:criterion}{{11.1}{124}{Closing inequality}{equation.619}{}} \newlabel{eq:record:criterion@cref}{{[equation][1][11]11.1}{[1][124][]124}{}{}{}} \newlabel{eq:cp:wrap-step}{{11.2}{124}{At a least counterexample, \texorpdfstring {$1\le \Theta +o(1)$}{1 <= Theta+o(1)}}{equation.620}{}} \newlabel{eq:cp:wrap-step@cref}{{[equation][2][11]11.2}{[1][124][]124}{}{}{}} \newlabel{eq:cp:mean-step}{{11.3}{125}{At a least counterexample, \texorpdfstring {$1\le \Theta +o(1)$}{1 <= Theta+o(1)}}{equation.621}{}} \newlabel{eq:cp:mean-step@cref}{{[equation][3][11]11.3}{[1][124][]125}{}{}{}} \newlabel{cor:joint-closing}{{11.2}{125}{Joint comparison and mean allocation}{corollary.623}{}} \newlabel{cor:joint-closing@cref}{{[corollary][2][11]11.2}{[1][125][]125}{}{}{}} \newlabel{rem:cp:trivial-mean}{{11.3}{125}{The trivial value of the mean constant}{remark.625}{}} \newlabel{rem:cp:trivial-mean@cref}{{[remark][3][11]11.3}{[1][125][]125}{}{}{}} \newlabel{subsec:cp:robust}{{11.2}{125}{Every error term comes from the two allowed remainders}{subsection.626}{}} \newlabel{subsec:cp:robust@cref}{{[subsection][2][11]11.2}{[1][125][]125}{}{}{}} \newlabel{lem:record:rec}{{11.4}{125}{The recurrence hypothesis}{lemma.628}{}} \newlabel{lem:record:rec@cref}{{[lemma][4][11]11.4}{[1][125][]125}{}{}{}} \newlabel{rem:cp:robust-final}{{11.5}{128}{Robustness of the final chain}{remark.635}{}} \newlabel{rem:cp:robust-final@cref}{{[remark][5][11]11.5}{[1][128][]128}{}{}{}} \newlabel{subsec:cp:proof}{{11.3}{129}{End of the proof: applying the baseline induction}{subsection.639}{}} \newlabel{subsec:cp:proof@cref}{{[subsection][3][11]11.3}{[1][129][]129}{}{}{}} \newlabel{subsec:cp:one-query}{{11.4}{129}{The case of one query (\texorpdfstring {\cref {prop:mech:one-query}}{Proposition \ref *{prop:mech:one-query}})}{subsection.640}{}} \newlabel{subsec:cp:one-query@cref}{{[subsection][4][11]11.4}{[1][129][]129}{}{}{}} \newlabel{rem:cp:one-query}{{11.6}{129}{Proof of the one-query proposition}{remark.642}{}} \newlabel{rem:cp:one-query@cref}{{[remark][6][11]11.6}{[1][129][]129}{}{}{}} \gdef \LT@ii {\LT@entry {1}{83.24507pt}\LT@entry {1}{183.56198pt}\LT@entry {1}{174.29381pt}} \newlabel{subsec:cp:table}{{11.5}{130}{Where the hypotheses are verified (table for Theorem~C)}{subsection.643}{}} \newlabel{subsec:cp:table@cref}{{[subsection][5][11]11.5}{[1][130][]130}{}{}{}} \newlabel{tab:hypotheses}{{5}{130}{Where the hypotheses of Theorem~C are verified}{table.lt.5}{}} \newlabel{tab:hypotheses@cref}{{[table][5][]5}{[1][130][]130}{}{}{}} \newlabel{sec:labellings}{{12}{132}{Square-constraint labellings over \texorpdfstring {$\mathbb F_p$}{Fp}}{section.645}{}} \newlabel{sec:labellings@cref}{{[section][12][]12}{[1][132][]132}{}{}{}} \newlabel{subsec:labellings:defs}{{12.1}{133}{Oriented graphs, labellings, and count errors}{subsection.649}{}} \newlabel{subsec:labellings:defs@cref}{{[subsection][1][12]12.1}{[1][133][]133}{}{}{}} \newlabel{def:graphs:labeling}{{12.1}{133}{Oriented graphs and strict-square labellings}{definition.651}{}} \newlabel{def:graphs:labeling@cref}{{[definition][1][12]12.1}{[1][133][]133}{}{}{}} \newlabel{eq:graphs:et}{{12.1}{133}{Oriented graphs, labellings, and count errors}{equation.652}{}} \newlabel{eq:graphs:et@cref}{{[equation][1][12]12.1}{[1][133][]133}{}{}{}} \newlabel{eq:graphs:graded}{{12.2}{133}{Oriented graphs, labellings, and count errors}{equation.653}{}} \newlabel{eq:graphs:graded@cref}{{[equation][2][12]12.2}{[1][133][]133}{}{}{}} \newlabel{it:et:mono}{{{{\textup {(E1)}}}}{133}{Oriented graphs, labellings, and count errors}{Item.654}{}} \newlabel{it:et:mono@cref}{{[enumi][1][]{{\textup {(E1)}}}}{[1][133][]133}{}{}{}} \newlabel{it:et:compare}{{{{\textup {(E2)}}}}{133}{Oriented graphs, labellings, and count errors}{Item.655}{}} \newlabel{it:et:compare@cref}{{[enumi][2][]{{\textup {(E2)}}}}{[1][133][]133}{}{}{}} \newlabel{it:et:poly}{{{{\textup {(E3)}}}}{133}{Oriented graphs, labellings, and count errors}{Item.656}{}} \newlabel{it:et:poly@cref}{{[enumi][3][]{{\textup {(E3)}}}}{[1][133][]133}{}{}{}} \newlabel{it:et:main}{{{{\textup {(E4)}}}}{133}{Oriented graphs, labellings, and count errors}{Item.657}{}} \newlabel{it:et:main@cref}{{[enumi][4][]{{\textup {(E4)}}}}{[1][133][]133}{}{}{}} \newlabel{subsec:labellings:extension}{{12.2}{134}{Counting choices for one new vertex}{subsection.658}{}} \newlabel{subsec:labellings:extension@cref}{{[subsection][2][12]12.2}{[1][133][]134}{}{}{}} \newlabel{lem:extension}{{12.2}{134}{Graded extension count}{lemma.660}{}} \newlabel{lem:extension@cref}{{[lemma][2][12]12.2}{[1][134][]134}{}{}{}} \newlabel{it:ext:soft}{{{{\textup {(a)}}}}{134}{Graded extension count}{Item.661}{}} \newlabel{it:ext:soft@cref}{{[enumi][1][]{{\textup {(a)}}}}{[1][134][]134}{}{}{}} \newlabel{it:ext:upper}{{{{\textup {(b)}}}}{134}{Graded extension count}{Item.662}{}} \newlabel{it:ext:upper@cref}{{[enumi][2][]{{\textup {(b)}}}}{[1][134][]134}{}{}{}} \newlabel{it:ext:lower}{{{{\textup {(c)}}}}{134}{Graded extension count}{Item.663}{}} \newlabel{it:ext:lower@cref}{{[enumi][3][]{{\textup {(c)}}}}{[1][134][]134}{}{}{}} \newlabel{it:ext:coarse}{{{{\textup {(d)}}}}{134}{Graded extension count}{Item.664}{}} \newlabel{it:ext:coarse@cref}{{[enumi][4][]{{\textup {(d)}}}}{[1][134][]134}{}{}{}} \newlabel{eq:ext:split}{{12.3}{134}{Counting choices for one new vertex}{equation.665}{}} \newlabel{eq:ext:split@cref}{{[equation][3][12]12.3}{[1][134][]134}{}{}{}} \newlabel{lem:record:signed-nbhd}{{12.3}{135}{Signed neighbourhoods}{corollary.667}{}} \newlabel{lem:record:signed-nbhd@cref}{{[corollary][3][12]12.3}{[1][135][]135}{}{}{}} \newlabel{subsec:labellings:sequential}{{12.3}{135}{Sequential counts and densities}{subsection.668}{}} \newlabel{subsec:labellings:sequential@cref}{{[subsection][3][12]12.3}{[1][135][]135}{}{}{}} \newlabel{def:graphs:error-pair}{{12.4}{135}{One-step error pairs}{definition.670}{}} \newlabel{def:graphs:error-pair@cref}{{[definition][4][12]12.4}{[1][135][]135}{}{}{}} \newlabel{lem:graphs:sequential}{{12.5}{135}{Sequential counts}{lemma.672}{}} \newlabel{lem:graphs:sequential@cref}{{[lemma][5][12]12.5}{[1][135][]135}{}{}{}} \newlabel{it:seq:count}{{{{\textup {(a)}}}}{135}{Sequential counts}{Item.673}{}} \newlabel{it:seq:count@cref}{{[enumi][1][]{{\textup {(a)}}}}{[1][135][]135}{}{}{}} \newlabel{it:seq:marg}{{{{\textup {(b)}}}}{135}{Sequential counts}{Item.674}{}} \newlabel{it:seq:marg@cref}{{[enumi][2][]{{\textup {(b)}}}}{[1][135][]135}{}{}{}} \newlabel{it:seq:rows}{{{{\textup {(c)}}}}{135}{Sequential counts}{Item.675}{}} \newlabel{it:seq:rows@cref}{{[enumi][3][]{{\textup {(c)}}}}{[1][135][]135}{}{}{}} \newlabel{it:seq:coarse}{{{{\textup {(d)}}}}{135}{Sequential counts}{Item.676}{}} \newlabel{it:seq:coarse@cref}{{[enumi][4][]{{\textup {(d)}}}}{[1][135][]135}{}{}{}} \newlabel{it:seq:thresholds}{{{{\textup {(e)}}}}{135}{Sequential counts}{Item.677}{}} \newlabel{it:seq:thresholds@cref}{{[enumi][5][]{{\textup {(e)}}}}{[1][135][]135}{}{}{}} \newlabel{lem:graphs:vertex}{{12.6}{136}{Vertices, subsets and conditional laws}{lemma.679}{}} \newlabel{lem:graphs:vertex@cref}{{[lemma][6][12]12.6}{[1][136][]136}{}{}{}} \newlabel{it:vertex:inv}{{{{\textup {(a)}}}}{136}{Vertices, subsets and conditional laws}{Item.680}{}} \newlabel{it:vertex:inv@cref}{{[enumi][1][]{{\textup {(a)}}}}{[1][136][]136}{}{}{}} \newlabel{it:vertex:dens}{{{{\textup {(b)}}}}{136}{Vertices, subsets and conditional laws}{Item.681}{}} \newlabel{it:vertex:dens@cref}{{[enumi][2][]{{\textup {(b)}}}}{[1][136][]136}{}{}{}} \newlabel{it:vertex:del}{{{{\textup {(c)}}}}{136}{Vertices, subsets and conditional laws}{Item.682}{}} \newlabel{it:vertex:del@cref}{{[enumi][3][]{{\textup {(c)}}}}{[1][136][]136}{}{}{}} \newlabel{it:vertex:subset}{{{{\textup {(d)}}}}{136}{Vertices, subsets and conditional laws}{Item.683}{}} \newlabel{it:vertex:subset@cref}{{[enumi][4][]{{\textup {(d)}}}}{[1][136][]136}{}{}{}} \newlabel{it:vertex:tuple}{{{{\textup {(e)}}}}{137}{Vertices, subsets and conditional laws}{Item.684}{}} \newlabel{it:vertex:tuple@cref}{{[enumi][5][]{{\textup {(e)}}}}{[1][137][]137}{}{}{}} \newlabel{subsec:labellings:four-count}{{12.4}{137}{Comparing two graph laws: a ratio of four counts}{subsection.685}{}} \newlabel{subsec:labellings:four-count@cref}{{[subsection][4][12]12.4}{[1][137][]137}{}{}{}} \newlabel{lem:four-count}{{12.7}{137}{Four-count comparison}{lemma.687}{}} \newlabel{lem:four-count@cref}{{[lemma][7][12]12.7}{[1][137][]137}{}{}{}} \newlabel{it:four:formula}{{{{\textup {(a)}}}}{137}{Four-count comparison}{Item.688}{}} \newlabel{it:four:formula@cref}{{[enumi][1][]{{\textup {(a)}}}}{[1][137][]137}{}{}{}} \newlabel{it:four:errors}{{{{\textup {(b)}}}}{138}{Four-count comparison}{Item.689}{}} \newlabel{it:four:errors@cref}{{[enumi][2][]{{\textup {(b)}}}}{[1][138][]138}{}{}{}} \newlabel{it:four:block}{{{{\textup {(c)}}}}{138}{Four-count comparison}{Item.690}{}} \newlabel{it:four:block@cref}{{[enumi][3][]{{\textup {(c)}}}}{[1][138][]138}{}{}{}} \newlabel{subsec:labellings:trace}{{12.5}{138}{How uniform is one label, or a queried pair, given the others?}{subsection.691}{}} \newlabel{subsec:labellings:trace@cref}{{[subsection][5][12]12.5}{[1][138][]138}{}{}{}} \newlabel{lem:trace-mixing}{{12.8}{138}{Trace lemma for conditional mixing}{lemma.693}{}} \newlabel{lem:trace-mixing@cref}{{[lemma][8][12]12.8}{[1][138][]138}{}{}{}} \newlabel{it:trace:slot}{{{{\textup {(a)}}}}{139}{Trace lemma for conditional mixing}{Item.694}{}} \newlabel{it:trace:slot@cref}{{[enumi][1][]{{\textup {(a)}}}}{[1][138][]139}{}{}{}} \newlabel{it:trace:pair}{{{{\textup {(b)}}}}{139}{Trace lemma for conditional mixing}{Item.695}{}} \newlabel{it:trace:pair@cref}{{[enumi][2][]{{\textup {(b)}}}}{[1][139][]139}{}{}{}} \newlabel{it:trace:explicit}{{{{\textup {(c)}}}}{139}{Trace lemma for conditional mixing}{Item.696}{}} \newlabel{it:trace:explicit@cref}{{[enumi][3][]{{\textup {(c)}}}}{[1][139][]139}{}{}{}} \newlabel{it:trace:72}{{{{\textup {(d)}}}}{139}{Trace lemma for conditional mixing}{Item.697}{}} \newlabel{it:trace:72@cref}{{[enumi][4][]{{\textup {(d)}}}}{[1][139][]139}{}{}{}} \newlabel{cert:trace-mixing-72}{{12.9}{141}{Mixing constants of the two-layer root at $p=2^{512}$}{certificate.699}{}} \newlabel{cert:trace-mixing-72@cref}{{[certificate][9][12]12.9}{[1][141][]141}{}{}{}} \newlabel{subsec:labellings:class-three}{{12.6}{141}{Primes \texorpdfstring {$p\equiv 3\pmod 4$}{p = 3 (mod 4)}: the Paley tournament, triples, and operators}{subsection.700}{}} \newlabel{subsec:labellings:class-three@cref}{{[subsection][6][12]12.6}{[1][141][]141}{}{}{}} \newlabel{lem:paley-triple}{{12.10}{141}{Paley-triple calculus}{lemma.702}{}} \newlabel{lem:paley-triple@cref}{{[lemma][10][12]12.10}{[1][141][]141}{}{}{}} \newlabel{it:paley:counts}{{{{\textup {(a)}}}}{141}{Paley-triple calculus}{Item.703}{}} \newlabel{it:paley:counts@cref}{{[enumi][1][]{{\textup {(a)}}}}{[1][141][]141}{}{}{}} \newlabel{it:paley:corr}{{{{\textup {(b)}}}}{141}{Paley-triple calculus}{Item.704}{}} \newlabel{it:paley:corr@cref}{{[enumi][2][]{{\textup {(b)}}}}{[1][141][]141}{}{}{}} \newlabel{it:paley:op}{{{{\textup {(c)}}}}{141}{Paley-triple calculus}{Item.705}{}} \newlabel{it:paley:op@cref}{{[enumi][3][]{{\textup {(c)}}}}{[1][141][]141}{}{}{}} \newlabel{it:paley:triples}{{{{\textup {(d)}}}}{141}{Paley-triple calculus}{Item.706}{}} \newlabel{it:paley:triples@cref}{{[enumi][4][]{{\textup {(d)}}}}{[1][141][]141}{}{}{}} \newlabel{it:paley:features}{{{{\textup {(e)}}}}{142}{Paley-triple calculus}{Item.707}{}} \newlabel{it:paley:features@cref}{{[enumi][5][]{{\textup {(e)}}}}{[1][142][]142}{}{}{}} \newlabel{it:paley:perturb}{{{{\textup {(f)}}}}{142}{Paley-triple calculus}{Item.708}{}} \newlabel{it:paley:perturb@cref}{{[enumi][6][]{{\textup {(f)}}}}{[1][142][]142}{}{}{}} \newlabel{sec:frontier:empty-triple-negative}{{12.11}{144}{The disjoint-triple operator}{lemma.710}{}} \newlabel{sec:frontier:empty-triple-negative@cref}{{[lemma][11][12]12.11}{[1][144][]144}{}{}{}} \newlabel{it:triple:spec}{{{{\textup {(a)}}}}{144}{The disjoint-triple operator}{Item.711}{}} \newlabel{it:triple:spec@cref}{{[enumi][1][]{{\textup {(a)}}}}{[1][144][]144}{}{}{}} \newlabel{eq:triple:spectrum}{{12.4}{144}{The disjoint-triple operator}{equation.712}{}} \newlabel{eq:triple:spectrum@cref}{{[equation][4][12]12.4}{[1][144][]144}{}{}{}} \newlabel{it:triple:bound}{{{{\textup {(b)}}}}{144}{The disjoint-triple operator}{Item.713}{}} \newlabel{it:triple:bound@cref}{{[enumi][2][]{{\textup {(b)}}}}{[1][144][]144}{}{}{}} \newlabel{it:triple:block}{{{{\textup {(c)}}}}{144}{The disjoint-triple operator}{Item.714}{}} \newlabel{it:triple:block@cref}{{[enumi][3][]{{\textup {(c)}}}}{[1][144][]144}{}{}{}} \newlabel{sec:cuts}{{13}{145}{Cuts of graph laws: the cut operator and correlations after pinning}{section.716}{}} \newlabel{sec:cuts@cref}{{[section][13][]13}{[1][145][]145}{}{}{}} \newlabel{subsec:cuts:data}{{13.1}{145}{A graph with an involution, and its cut operator}{subsection.718}{}} \newlabel{subsec:cuts:data@cref}{{[subsection][1][13]13.1}{[1][145][]145}{}{}{}} \newlabel{def:spec:data}{{13.1}{145}{Spectral data}{definition.720}{}} \newlabel{def:spec:data@cref}{{[definition][1][13]13.1}{[1][145][]145}{}{}{}} \newlabel{eq:spec:Rcut}{{13.1}{146}{Spectral data}{equation.722}{}} \newlabel{eq:spec:Rcut@cref}{{[equation][1][13]13.1}{[1][146][]146}{}{}{}} \newlabel{lem:spec:elementary}{{13.2}{146}{Elementary facts}{lemma.725}{}} \newlabel{lem:spec:elementary@cref}{{[lemma][2][13]13.2}{[1][146][]146}{}{}{}} \newlabel{lem:spec:cutkernel}{{13.3}{146}{Cut kernel}{lemma.727}{}} \newlabel{lem:spec:cutkernel@cref}{{[lemma][3][13]13.3}{[1][146][]146}{}{}{}} \newlabel{eq:spec:K}{{13.2}{146}{Cut kernel}{equation.729}{}} \newlabel{eq:spec:K@cref}{{[equation][2][13]13.2}{[1][146][]146}{}{}{}} \newlabel{lem:cut-transport}{{13.4}{148}{Transport along isomorphisms}{lemma.736}{}} \newlabel{lem:cut-transport@cref}{{[lemma][4][13]13.4}{[1][148][]148}{}{}{}} \newlabel{subsec:cuts:blocks}{{13.2}{148}{From mean-zero bounds to operator bounds}{subsection.737}{}} \newlabel{subsec:cuts:blocks@cref}{{[subsection][2][13]13.2}{[1][148][]148}{}{}{}} \newlabel{lem:block-completion}{{13.5}{149}{Block completion}{lemma.739}{}} \newlabel{lem:block-completion@cref}{{[lemma][5][13]13.5}{[1][149][]149}{}{}{}} \newlabel{prop:matching:positive}{{13.6}{149}{Positive envelope from the mean-zero compression}{proposition.743}{}} \newlabel{prop:matching:positive@cref}{{[proposition][6][13]13.6}{[1][149][]149}{}{}{}} \newlabel{lem:spec:tensorcomp}{{13.7}{150}{Tensor products of compressions}{lemma.746}{}} \newlabel{lem:spec:tensorcomp@cref}{{[lemma][7][13]13.7}{[1][150][]150}{}{}{}} \newlabel{lem:weighted-frame}{{13.8}{151}{Weighted frames}{lemma.752}{}} \newlabel{lem:weighted-frame@cref}{{[lemma][8][13]13.8}{[1][151][]151}{}{}{}} \newlabel{lem:swapped-rectangle}{{13.9}{153}{Swapped rectangular kernels}{lemma.758}{}} \newlabel{lem:swapped-rectangle@cref}{{[lemma][9][13]13.9}{[1][153][]153}{}{}{}} \newlabel{subsec:cuts:influence}{{13.3}{154}{Correlations after fixing coordinates}{subsection.763}{}} \newlabel{subsec:cuts:influence@cref}{{[subsection][3][13]13.3}{[1][154][]154}{}{}{}} \newlabel{def:mid:influence}{{13.10}{155}{Influence data}{definition.765}{}} \newlabel{def:mid:influence@cref}{{[definition][10][13]13.10}{[1][155][]155}{}{}{}} \newlabel{eq:mid:standing}{{13.3}{155}{Influence data}{equation.767}{}} \newlabel{eq:mid:standing@cref}{{[equation][3][13]13.3}{[1][155][]155}{}{}{}} \newlabel{eq:mid:epsij}{{13.4}{155}{Influence data}{equation.769}{}} \newlabel{eq:mid:epsij@cref}{{[equation][4][13]13.4}{[1][155][]155}{}{}{}} \newlabel{eq:spec:S2}{{13.5}{155}{Influence conditions}{equation.772}{}} \newlabel{eq:spec:S2@cref}{{[equation][5][13]13.5}{[1][155][]155}{}{}{}} \newlabel{lem:mid:pinpair}{{13.12}{156}{Fully pinned pairs}{lemma.774}{}} \newlabel{lem:mid:pinpair@cref}{{[lemma][12][13]13.12}{[1][155][]156}{}{}{}} \newlabel{lem:mid:connect}{{13.13}{156}{Connectivity of pinned state spaces}{lemma.776}{}} \newlabel{lem:mid:connect@cref}{{[lemma][13][13]13.13}{[1][156][]156}{}{}{}} \newlabel{lem:mid:subspaces}{{13.14}{157}{Coordinate subspaces}{lemma.778}{}} \newlabel{lem:mid:subspaces@cref}{{[lemma][14][13]13.14}{[1][157][]157}{}{}{}} \newlabel{lem:mid:allpin}{{13.15}{157}{All partial pinnings: Kassabov--Schur elimination}{lemma.783}{}} \newlabel{lem:mid:allpin@cref}{{[lemma][15][13]13.15}{[1][157][]157}{}{}{}} \newlabel{prop:middle-negative}{{13.16}{158}{Pinned influence theorem}{proposition.785}{}} \newlabel{prop:middle-negative@cref}{{[proposition][16][13]13.16}{[1][158][]158}{}{}{}} \newlabel{cor:influence-schur}{{13.17}{158}{Schur-test form}{corollary.789}{}} \newlabel{cor:influence-schur@cref}{{[corollary][17][13]13.17}{[1][158][]158}{}{}{}} \newlabel{rem:influence-uses}{{13.18}{159}{Uses and the certified forms}{remark.791}{}} \newlabel{rem:influence-uses@cref}{{[remark][18][13]13.18}{[1][159][]159}{}{}{}} \newlabel{subsec:cuts:recentering}{{13.4}{159}{Recentring: from reference means to actual marginal means}{subsection.792}{}} \newlabel{subsec:cuts:recentering@cref}{{[subsection][4][13]13.4}{[1][159][]159}{}{}{}} \newlabel{lem:recentering}{{13.19}{159}{Recentering}{lemma.794}{}} \newlabel{lem:recentering@cref}{{[lemma][19][13]13.19}{[1][159][]159}{}{}{}} \newlabel{rem:recentering-uses}{{13.20}{160}{Instances}{remark.799}{}} \newlabel{rem:recentering-uses@cref}{{[remark][20][13]13.20}{[1][160][]160}{}{}{}} \newlabel{subsec:cuts:actual}{{13.5}{160}{Marginals of the law itself (actual marginals)}{subsection.800}{}} \newlabel{subsec:cuts:actual@cref}{{[subsection][5][13]13.5}{[1][160][]160}{}{}{}} \newlabel{lem:record:actual-correlation}{{13.21}{160}{Actual marginals}{lemma.802}{}} \newlabel{lem:record:actual-correlation@cref}{{[lemma][21][13]13.21}{[1][160][]160}{}{}{}} \newlabel{lem:tilt-marginals}{{13.22}{161}{Marginals of a positive quadratic tilt}{lemma.807}{}} \newlabel{lem:tilt-marginals@cref}{{[lemma][22][13]13.22}{[1][161][]161}{}{}{}} \newlabel{subsec:cuts:restriction}{{13.6}{162}{Restriction to an injectivity event}{subsection.808}{}} \newlabel{subsec:cuts:restriction@cref}{{[subsection][6][13]13.6}{[1][162][]162}{}{}{}} \newlabel{lem:restriction}{{13.23}{162}{Restriction to an injectivity event}{lemma.810}{}} \newlabel{lem:restriction@cref}{{[lemma][23][13]13.23}{[1][162][]162}{}{}{}} \newlabel{subsec:cuts:projection}{{13.7}{163}{Kernels depending on few coordinates}{subsection.815}{}} \newlabel{subsec:cuts:projection@cref}{{[subsection][7][13]13.7}{[1][163][]163}{}{}{}} \newlabel{lem:record:projection}{{13.24}{163}{Projected kernels}{lemma.817}{}} \newlabel{lem:record:projection@cref}{{[lemma][24][13]13.24}{[1][163][]163}{}{}{}} \newlabel{subsec:cuts:rows}{{13.8}{164}{Conditional laws given the middle label, under a change of reference}{subsection.820}{}} \newlabel{subsec:cuts:rows@cref}{{[subsection][8][13]13.8}{[1][164][]164}{}{}{}} \newlabel{lem:row-comparison}{{13.25}{164}{Row comparison}{lemma.822}{}} \newlabel{lem:row-comparison@cref}{{[lemma][25][13]13.25}{[1][164][]164}{}{}{}} \newlabel{rem:row-comparison-uses}{{13.26}{164}{Instances}{remark.827}{}} \newlabel{rem:row-comparison-uses@cref}{{[remark][26][13]13.26}{[1][164][]164}{}{}{}} \newlabel{sec:spectral}{{14}{165}{Spectral criteria for cut operators}{section.829}{}} \newlabel{sec:spectral@cref}{{[section][14][]14}{[1][165][]165}{}{}{}} \newlabel{subsec:spec:fourier}{{14.1}{166}{Single-variable Fourier analysis}{subsection.833}{}} \newlabel{subsec:spec:fourier@cref}{{[subsection][1][14]14.1}{[1][166][]166}{}{}{}} \newlabel{lem:spec:gauss}{{14.1}{166}{The Gauss operator}{lemma.835}{}} \newlabel{lem:spec:gauss@cref}{{[lemma][1][14]14.1}{[1][166][]166}{}{}{}} \newlabel{lem:spec:affpair}{{14.2}{166}{$\mathrm {Aff}_p$-invariant kernels}{lemma.837}{}} \newlabel{lem:spec:affpair@cref}{{[lemma][2][14]14.2}{[1][166][]166}{}{}{}} \newlabel{eq:spec:affpair}{{14.1}{166}{$\mathrm {Aff}_p$-invariant kernels}{equation.840}{}} \newlabel{eq:spec:affpair@cref}{{[equation][1][14]14.1}{[1][166][]166}{}{}{}} \newlabel{eq:spec:smallconst}{{14.2}{168}{Single-variable Fourier analysis}{equation.843}{}} \newlabel{eq:spec:smallconst@cref}{{[equation][2][14]14.2}{[1][168][]168}{}{}{}} \newlabel{lem:spec:small}{{14.3}{168}{Small pair constants}{lemma.845}{}} \newlabel{lem:spec:small@cref}{{[lemma][3][14]14.3}{[1][168][]168}{}{}{}} \newlabel{subsec:spec:actual-stars}{{14.2}{168}{Exact star factorisation in a fixed invariant half law}{subsection.848}{}} \newlabel{subsec:spec:actual-stars@cref}{{[subsection][2][14]14.2}{[1][168][]168}{}{}{}} \newlabel{lem:general-star}{{14.4}{169}{Complete actual star synthesis}{lemma.851}{}} \newlabel{lem:general-star@cref}{{[lemma][4][14]14.4}{[1][169][]169}{}{}{}} \newlabel{eq:star-diagonal}{{14.3}{169}{Complete actual star synthesis}{equation.853}{}} \newlabel{eq:star-diagonal@cref}{{[equation][3][14]14.3}{[1][169][]169}{}{}{}} \newlabel{eq:star-cross}{{14.4}{169}{Complete actual star synthesis}{equation.855}{}} \newlabel{eq:star-cross@cref}{{[equation][4][14]14.4}{[1][169][]169}{}{}{}} \newlabel{eq:star-cross-bound}{{14.5}{169}{Complete actual star synthesis}{equation.857}{}} \newlabel{eq:star-cross-bound@cref}{{[equation][5][14]14.5}{[1][169][]169}{}{}{}} \newlabel{eq:singleton-star}{{14.6}{169}{Complete actual star synthesis}{equation.859}{}} \newlabel{eq:singleton-star@cref}{{[equation][6][14]14.6}{[1][169][]169}{}{}{}} \newlabel{eq:pair-overlap}{{14.7}{169}{Complete actual star synthesis}{equation.861}{}} \newlabel{eq:pair-overlap@cref}{{[equation][7][14]14.7}{[1][169][]169}{}{}{}} \newlabel{eq:star-traces}{{14.8}{170}{Setting}{equation.863}{}} \newlabel{eq:star-traces@cref}{{[equation][8][14]14.8}{[1][169][]170}{}{}{}} \newlabel{cor:star-matrix}{{14.5}{171}{Complete star matrix}{corollary.865}{}} \newlabel{cor:star-matrix@cref}{{[corollary][5][14]14.5}{[1][171][]171}{}{}{}} \newlabel{lem:hidden-feature}{{14.6}{172}{Unobserved features}{lemma.867}{}} \newlabel{lem:hidden-feature@cref}{{[lemma][6][14]14.6}{[1][172][]172}{}{}{}} \newlabel{rem:realified-gates}{{14.7}{172}{Real forms of the phase gates}{remark.869}{}} \newlabel{rem:realified-gates@cref}{{[remark][7][14]14.7}{[1][172][]172}{}{}{}} \newlabel{subsec:spec:degone}{{14.3}{173}{The degree-one part}{subsection.870}{}} \newlabel{subsec:spec:degone@cref}{{[subsection][3][14]14.3}{[1][173][]173}{}{}{}} \newlabel{eq:spec:Azero}{{14.9}{173}{The degree-one part}{equation.873}{}} \newlabel{eq:spec:Azero@cref}{{[equation][9][14]14.9}{[1][173][]173}{}{}{}} \newlabel{eq:spec:epsV}{{14.10}{173}{The degree-one part}{equation.874}{}} \newlabel{eq:spec:epsV@cref}{{[equation][10][14]14.10}{[1][173][]173}{}{}{}} \newlabel{lem:spec:degone}{{14.8}{173}{The degree-one block}{lemma.876}{}} \newlabel{lem:spec:degone@cref}{{[lemma][8][14]14.8}{[1][173][]173}{}{}{}} \newlabel{subsec:spec:coupling}{{14.4}{174}{Coupling degree-one functions to the remainder}{subsection.880}{}} \newlabel{subsec:spec:coupling@cref}{{[subsection][4][14]14.4}{[1][174][]174}{}{}{}} \newlabel{def:coupling-data}{{14.9}{174}{Coupling data}{definition.882}{}} \newlabel{def:coupling-data@cref}{{[definition][9][14]14.9}{[1][174][]174}{}{}{}} \newlabel{eq:spec:Rprime}{{14.11}{175}{Coupling degree-one functions to the remainder}{equation.887}{}} \newlabel{eq:spec:Rprime@cref}{{[equation][11][14]14.11}{[1][175][]175}{}{}{}} \newlabel{lem:coupling-modes}{{14.10}{175}{Modes of coupling data}{lemma.890}{}} \newlabel{lem:coupling-modes@cref}{{[lemma][10][14]14.10}{[1][175][]175}{}{}{}} \newlabel{eq:spec:H}{{14.12}{175}{The model}{equation.892}{}} \newlabel{eq:spec:H@cref}{{[equation][12][14]14.12}{[1][175][]175}{}{}{}} \newlabel{def:coupling-model}{{14.11}{175}{The coupling model}{definition.894}{}} \newlabel{def:coupling-model@cref}{{[definition][11][14]14.11}{[1][175][]175}{}{}{}} \newlabel{eq:spec:beta}{{14.13}{176}{The Gram comparison}{equation.896}{}} \newlabel{eq:spec:beta@cref}{{[equation][13][14]14.13}{[1][176][]176}{}{}{}} \newlabel{lem:spec2:gram}{{14.12}{176}{Gram comparison}{lemma.898}{}} \newlabel{lem:spec2:gram@cref}{{[lemma][12][14]14.12}{[1][176][]176}{}{}{}} \newlabel{eq:spec:rem}{{14.14}{177}{The Paley part}{equation.900}{}} \newlabel{eq:spec:rem@cref}{{[equation][14][14]14.14}{[1][177][]177}{}{}{}} \newlabel{lem:spec2:paley}{{14.13}{177}{The Paley part}{lemma.902}{}} \newlabel{lem:spec2:paley@cref}{{[lemma][13][14]14.13}{[1][177][]177}{}{}{}} \newlabel{cor:spec2:coupling}{{14.14}{178}{The coupling block}{lemma.907}{}} \newlabel{cor:spec2:coupling@cref}{{[lemma][14][14]14.14}{[1][178][]178}{}{}{}} \newlabel{eq:spec:etaB}{{14.15}{178}{The coupling block}{equation.908}{}} \newlabel{eq:spec:etaB@cref}{{[equation][15][14]14.15}{[1][178][]178}{}{}{}} \newlabel{eq:spec:coupling}{{14.16}{178}{The coupling block}{equation.909}{}} \newlabel{eq:spec:coupling@cref}{{[equation][16][14]14.16}{[1][178][]178}{}{}{}} \newlabel{subsec:spec:completion-variance}{{14.5}{179}{Variance of completion counts}{subsection.910}{}} \newlabel{subsec:spec:completion-variance@cref}{{[subsection][5][14]14.5}{[1][179][]179}{}{}{}} \newlabel{lem:push:localvariance}{{14.15}{179}{Completion variance}{lemma.912}{}} \newlabel{lem:push:localvariance@cref}{{[lemma][15][14]14.15}{[1][179][]179}{}{}{}} \newlabel{eq:push:localvariance}{{14.17}{180}{Completion variance}{equation.917}{}} \newlabel{eq:push:localvariance@cref}{{[equation][17][14]14.17}{[1][180][]180}{}{}{}} \newlabel{lem:projection-diagonal}{{14.16}{182}{Projection-error diagonal}{lemma.919}{}} \newlabel{lem:projection-diagonal@cref}{{[lemma][16][14]14.16}{[1][182][]182}{}{}{}} \newlabel{eq:push:projectiondiagonal}{{14.18}{182}{Projection-error diagonal}{equation.920}{}} \newlabel{eq:push:projectiondiagonal@cref}{{[equation][18][14]14.18}{[1][182][]182}{}{}{}} \newlabel{lem:push:conditionalgram}{{14.17}{182}{Conditional-density Gram refinement}{lemma.922}{}} \newlabel{lem:push:conditionalgram@cref}{{[lemma][17][14]14.17}{[1][182][]182}{}{}{}} \newlabel{eq:push:conditionalgram}{{14.19}{182}{Conditional-density Gram refinement}{equation.923}{}} \newlabel{eq:push:conditionalgram@cref}{{[equation][19][14]14.19}{[1][182][]182}{}{}{}} \newlabel{subsec:spec:perp}{{14.6}{183}{The character expansion}{subsection.924}{}} \newlabel{subsec:spec:perp@cref}{{[subsection][6][14]14.6}{[1][183][]183}{}{}{}} \newlabel{lem:spec:expansion}{{14.18}{183}{Expansion}{lemma.926}{}} \newlabel{lem:spec:expansion@cref}{{[lemma][18][14]14.18}{[1][183][]183}{}{}{}} \newlabel{eq:record:root-kernel}{{14.20}{183}{Expansion}{equation.927}{}} \newlabel{eq:record:root-kernel@cref}{{[equation][20][14]14.20}{[1][183][]183}{}{}{}} \newlabel{lem:spec:stars}{{14.19}{183}{Stars}{lemma.929}{}} \newlabel{lem:spec:stars@cref}{{[lemma][19][14]14.19}{[1][183][]183}{}{}{}} \newlabel{subsec:spec:centring}{{14.7}{184}{Centring at the half-law mean}{subsection.934}{}} \newlabel{subsec:spec:centring@cref}{{[subsection][7][14]14.7}{[1][184][]184}{}{}{}} \newlabel{prop:spec2:mucentre}{{14.20}{184}{Centring at the $\mu $-mean}{proposition.936}{}} \newlabel{prop:spec2:mucentre@cref}{{[proposition][20][14]14.20}{[1][184][]184}{}{}{}} \newlabel{it:centre:decomp}{{{{\textup {(a)}}}}{184}{Centring at the $\mu $-mean}{Item.937}{}} \newlabel{it:centre:decomp@cref}{{[enumi][1][]{{\textup {(a)}}}}{[1][184][]184}{}{}{}} \newlabel{it:centre:form}{{{{\textup {(b)}}}}{184}{Centring at the $\mu $-mean}{Item.938}{}} \newlabel{it:centre:form@cref}{{[enumi][2][]{{\textup {(b)}}}}{[1][184][]184}{}{}{}} \newlabel{it:centre:inputs}{{{{\textup {(c)}}}}{184}{Centring at the $\mu $-mean}{Item.939}{}} \newlabel{it:centre:inputs@cref}{{[enumi][3][]{{\textup {(c)}}}}{[1][184][]184}{}{}{}} \newlabel{it:centre:Z}{{{{\textup {(c1)}}}}{184}{Centring at the $\mu $-mean}{Item.940}{}} \newlabel{it:centre:Z@cref}{{[enumii][1][3]{{\textup {(c1)}}}}{[1][184][]184}{}{}{}} \newlabel{it:centre:sup}{{{{\textup {(c2)}}}}{184}{Centring at the $\mu $-mean}{Item.941}{}} \newlabel{it:centre:sup@cref}{{[enumii][2][3]{{\textup {(c2)}}}}{[1][184][]184}{}{}{}} \newlabel{it:centre:rho}{{{{\textup {(c3)}}}}{184}{Centring at the $\mu $-mean}{Item.942}{}} \newlabel{it:centre:rho@cref}{{[enumii][3][3]{{\textup {(c3)}}}}{[1][184][]184}{}{}{}} \newlabel{it:centre:perp}{{{{\textup {(c4)}}}}{184}{Centring at the $\mu $-mean}{Item.943}{}} \newlabel{it:centre:perp@cref}{{[enumii][4][3]{{\textup {(c4)}}}}{[1][184][]184}{}{}{}} \newlabel{it:centre:cperp}{{{{\textup {(c5)}}}}{184}{Centring at the $\mu $-mean}{Item.944}{}} \newlabel{it:centre:cperp@cref}{{[enumii][5][3]{{\textup {(c5)}}}}{[1][184][]184}{}{}{}} \newlabel{it:centre:standard}{{{{\textup {(d)}}}}{184}{Centring at the $\mu $-mean}{Item.945}{}} \newlabel{it:centre:standard@cref}{{[enumi][4][]{{\textup {(d)}}}}{[1][184][]184}{}{}{}} \newlabel{subsec:spec:routeA}{{14.8}{185}{Route~A (conditional laws, centring at the half-law mean)}{subsection.946}{}} \newlabel{subsec:spec:routeA@cref}{{[subsection][8][14]14.8}{[1][185][]185}{}{}{}} \newlabel{thm:spectral-criterion}{{14.21}{185}{Spectral criterion centred at the half-law mean (Route~A)}{theorem.948}{}} \newlabel{thm:spectral-criterion@cref}{{[theorem][21][14]14.21}{[1][185][]185}{}{}{}} \newlabel{eq:spectral-test}{{14.21}{185}{Spectral criterion centred at the half-law mean (Route~A)}{equation.952}{}} \newlabel{eq:spectral-test@cref}{{[equation][21][14]14.21}{[1][185][]185}{}{}{}} \newlabel{cor:spectral-criterion-blocks}{{14.22}{185}{Blocks}{corollary.958}{}} \newlabel{cor:spectral-criterion-blocks@cref}{{[corollary][22][14]14.22}{[1][185][]185}{}{}{}} \newlabel{rem:spectral-criterion:influence}{{14.23}{187}{Pinned correlations of the half law are not used}{remark.960}{}} \newlabel{rem:spectral-criterion:influence@cref}{{[remark][23][14]14.23}{[1][186][]187}{}{}{}} \newlabel{rem:spectral-criterion:row}{{14.24}{187}{The row-norm criterion}{remark.962}{}} \newlabel{rem:spectral-criterion:row@cref}{{[remark][24][14]14.24}{[1][187][]187}{}{}{}} \newlabel{rem:spectral-criterion:history}{{14.25}{187}{The earlier criteria}{remark.964}{}} \newlabel{rem:spectral-criterion:history@cref}{{[remark][25][14]14.25}{[1][187][]187}{}{}{}} \newlabel{rem:spectral-criterion:uses}{{14.26}{187}{Where route A is applied}{remark.966}{}} \newlabel{rem:spectral-criterion:uses@cref}{{[remark][26][14]14.26}{[1][187][]187}{}{}{}} \newlabel{subsec:spec:routeB}{{14.9}{188}{Route~B (uniform averages over allowed sets)}{subsection.970}{}} \newlabel{subsec:spec:routeB@cref}{{[subsection][9][14]14.9}{[1][187][]188}{}{}{}} \newlabel{thm:record:direct-star}{{14.27}{188}{Spectral criterion from uniform averages over allowed sets (Route~B)}{theorem.973}{}} \newlabel{thm:record:direct-star@cref}{{[theorem][27][14]14.27}{[1][188][]188}{}{}{}} \newlabel{it:record:star-H1}{{{{\textup {(H1)}}}}{188}{Spectral criterion from uniform averages over allowed sets (Route~B)}{Item.974}{}} \newlabel{it:record:star-H1@cref}{{[enumi][1][]{{\textup {(H1)}}}}{[1][188][]188}{}{}{}} \newlabel{it:record:star-H2}{{{{\textup {(H2)}}}}{188}{Spectral criterion from uniform averages over allowed sets (Route~B)}{Item.975}{}} \newlabel{it:record:star-H2@cref}{{[enumi][2][]{{\textup {(H2)}}}}{[1][188][]188}{}{}{}} \newlabel{eq:record:schur}{{14.22}{188}{Spectral criterion from uniform averages over allowed sets (Route~B)}{equation.976}{}} \newlabel{eq:record:schur@cref}{{[equation][22][14]14.22}{[1][188][]188}{}{}{}} \newlabel{it:record:star-H3}{{{{\textup {(H3)}}}}{188}{Spectral criterion from uniform averages over allowed sets (Route~B)}{Item.977}{}} \newlabel{it:record:star-H3@cref}{{[enumi][3][]{{\textup {(H3)}}}}{[1][188][]188}{}{}{}} \newlabel{lem:record:frame-inputs}{{14.28}{190}{Inputs for the star synthesis at the root cuts}{lemma.984}{}} \newlabel{lem:record:frame-inputs@cref}{{[lemma][28][14]14.28}{[1][190][]190}{}{}{}} \newlabel{subsec:spec:thresholds}{{14.10}{191}{From one prime to all primes and blocks}{subsection.988}{}} \newlabel{subsec:spec:thresholds@cref}{{[subsection][10][14]14.10}{[1][191][]191}{}{}{}} \newlabel{lem:spectral-monotone}{{14.29}{191}{Monotone spectral quantities}{lemma.990}{}} \newlabel{lem:spectral-monotone@cref}{{[lemma][29][14]14.29}{[1][191][]191}{}{}{}} \newlabel{rem:spectral-criterion:certificate}{{14.30}{192}{How a cap is certified}{remark.996}{}} \newlabel{rem:spectral-criterion:certificate@cref}{{[remark][30][14]14.30}{[1][192][]192}{}{}{}} \newlabel{subsec:advance:parity}{{14.11}{192}{Primes \texorpdfstring {$p\equiv 1\pmod 4$}{p = 1 (mod 4)}: extra terms (large primes only)}{subsection.997}{}} \newlabel{subsec:advance:parity@cref}{{[subsection][11][14]14.11}{[1][192][]192}{}{}{}} \newlabel{lem:spec2:paley-one}{{14.31}{192}{Class-one Paley terms}{lemma.999}{}} \newlabel{lem:spec2:paley-one@cref}{{[lemma][31][14]14.31}{[1][192][]192}{}{}{}} \newlabel{lem:spec2:parity-transfer}{{14.32}{193}{Transfer of the non-coverable Paley averages}{lemma.1001}{}} \newlabel{lem:spec2:parity-transfer@cref}{{[lemma][32][14]14.32}{[1][193][]193}{}{}{}} \newlabel{sec:dl}{{15}{193}{Second-order character sums: \texorpdfstring {$O(p^{-1})$}{O(p\textasciicircum (-1))} where Weil gives \texorpdfstring {$O(p^{-1/2})$}{O(p\textasciicircum (-1/2))}}{section.1003}{}} \newlabel{sec:dl@cref}{{[section][15][]15}{[1][193][]193}{}{}{}} \newlabel{subsec:dl:K}{{15.1}{194}{The four-cycle kernel}{subsection.1008}{}} \newlabel{subsec:dl:K@cref}{{[subsection][1][15]15.1}{[1][194][]194}{}{}{}} \newlabel{eq:dl:M}{{15.1}{194}{Notation}{equation.1010}{}} \newlabel{eq:dl:M@cref}{{[equation][1][15]15.1}{[1][194][]194}{}{}{}} \newlabel{lem:dl:invariance}{{15.1}{195}{Invariance}{lemma.1012}{}} \newlabel{lem:dl:invariance@cref}{{[lemma][1][15]15.1}{[1][195][]195}{}{}{}} \newlabel{lem:dl:group}{{15.2}{195}{Classes and characters of $\Gamma $}{lemma.1016}{}} \newlabel{lem:dl:group@cref}{{[lemma][2][15]15.2}{[1][195][]195}{}{}{}} \newlabel{eq:dl:classsum}{{15.2}{195}{Classes and characters of $\Gamma $}{equation.1018}{}} \newlabel{eq:dl:classsum@cref}{{[equation][2][15]15.2}{[1][195][]195}{}{}{}} \newlabel{lem:dl:decomp}{{15.3}{197}{Decomposition}{lemma.1021}{}} \newlabel{lem:dl:decomp@cref}{{[lemma][3][15]15.3}{[1][197][]197}{}{}{}} \newlabel{lem:dl:schur}{{15.4}{197}{Eigenvalue on a multiplicity-one constituent}{lemma.1023}{}} \newlabel{lem:dl:schur@cref}{{[lemma][4][15]15.4}{[1][197][]197}{}{}{}} \newlabel{lem:dl:Phi}{{15.5}{197}{The function $\Phi $}{lemma.1025}{}} \newlabel{lem:dl:Phi@cref}{{[lemma][5][15]15.5}{[1][197][]197}{}{}{}} \newlabel{eq:dl:trace2}{{15.3}{198}{Notation}{equation.1029}{}} \newlabel{eq:dl:trace2@cref}{{[equation][3][15]15.3}{[1][198][]198}{}{}{}} \newlabel{lem:dl:line}{{15.6}{198}{Line sums}{lemma.1031}{}} \newlabel{lem:dl:line@cref}{{[lemma][6][15]15.6}{[1][198][]198}{}{}{}} \newlabel{lem:dl:split}{{15.7}{198}{Torus sums}{lemma.1033}{}} \newlabel{lem:dl:split@cref}{{[lemma][7][15]15.7}{[1][198][]198}{}{}{}} \newlabel{thm:dl:K}{{15.8}{199}{Four-cycle operator norm}{theorem.1038}{}} \newlabel{thm:dl:K@cref}{{[theorem][8][15]15.8}{[1][199][]199}{}{}{}} \newlabel{cor:dl:normalized}{{15.9}{200}{The four-cycle kernel for uniform probability}{corollary.1040}{}} \newlabel{cor:dl:normalized@cref}{{[corollary][9][15]15.9}{[1][200][]200}{}{}{}} \newlabel{eq:dl:normalized}{{15.4}{200}{The four-cycle kernel for uniform probability}{equation.1042}{}} \newlabel{eq:dl:normalized@cref}{{[equation][4][15]15.4}{[1][200][]200}{}{}{}} \newlabel{cor:raw-pair-maps}{{15.10}{201}{Raw pair maps}{corollary.1045}{}} \newlabel{cor:raw-pair-maps@cref}{{[corollary][10][15]15.10}{[1][201][]201}{}{}{}} \newlabel{eq:raw-pair-split}{{15.5}{201}{Raw pair maps}{equation.1048}{}} \newlabel{eq:raw-pair-split@cref}{{[equation][5][15]15.5}{[1][201][]201}{}{}{}} \newlabel{rem:dl:K-sharp}{{15.11}{202}{The constant $2$}{remark.1050}{}} \newlabel{rem:dl:K-sharp@cref}{{[remark][11][15]15.11}{[1][202][]202}{}{}{}} \newlabel{subsec:cubic-resultant}{{15.2}{203}{The complete three-by-three character kernel}{subsection.1051}{}} \newlabel{subsec:cubic-resultant@cref}{{[subsection][2][15]15.2}{[1][203][]203}{}{}{}} \newlabel{thm:cubic-resultant}{{15.12}{203}{Squarefree cubic resultant}{theorem.1053}{}} \newlabel{thm:cubic-resultant@cref}{{[theorem][12][15]15.12}{[1][203][]203}{}{}{}} \newlabel{eq:cubic-gram}{{15.6}{203}{The complete three-by-three character kernel}{equation.1054}{}} \newlabel{eq:cubic-gram@cref}{{[equation][6][15]15.6}{[1][203][]203}{}{}{}} \newlabel{subsec:dl:H2}{{15.3}{204}{A two-variable character sum}{subsection.1055}{}} \newlabel{subsec:dl:H2@cref}{{[subsection][3][15]15.3}{[1][204][]204}{}{}{}} \newlabel{eq:dl:B}{{15.7}{204}{A two-variable character sum}{equation.1056}{}} \newlabel{eq:dl:B@cref}{{[equation][7][15]15.7}{[1][204][]204}{}{}{}} \newlabel{thm:dl:H2}{{15.13}{204}{Two-variable character sum}{theorem.1058}{}} \newlabel{thm:dl:H2@cref}{{[theorem][13][15]15.13}{[1][204][]204}{}{}{}} \newlabel{lem:dl:sheaf}{{15.14}{205}{The sheaf of the family $y^2=f(x)(x-z)$}{lemma.1060}{}} \newlabel{lem:dl:sheaf@cref}{{[lemma][14][15]15.14}{[1][205][]205}{}{}{}} \newlabel{lem:tame-trace-bound}{{15.15}{206}{Tame trace bound}{lemma.1068}{}} \newlabel{lem:tame-trace-bound@cref}{{[lemma][15][15]15.15}{[1][206][]206}{}{}{}} \newlabel{rem:dl:H2-sharp}{{15.16}{208}{Sharpness and the coefficients of $\mathcal B$}{remark.1070}{}} \newlabel{rem:dl:H2-sharp@cref}{{[remark][16][15]15.16}{[1][208][]208}{}{}{}} \newlabel{subsec:moving-root}{{15.4}{208}{Trace functions with one free label}{subsection.1071}{}} \newlabel{subsec:moving-root@cref}{{[subsection][4][15]15.4}{[1][208][]208}{}{}{}} \newlabel{subsec:advance:conditional-star}{{15.4.1}{208}{Trace functions and stars}{subsubsection.1072}{}} \newlabel{subsec:advance:conditional-star@cref}{{[subsubsection][1][15,4]15.4.1}{[1][208][]208}{}{}{}} \newlabel{eq:moving-root-tau}{{15.8}{208}{Trace functions and stars}{equation.1073}{}} \newlabel{eq:moving-root-tau@cref}{{[equation][8][15]15.8}{[1][208][]208}{}{}{}} \newlabel{lem:moving-root-trace}{{15.17}{208}{Moving-root traces}{lemma.1075}{}} \newlabel{lem:moving-root-trace@cref}{{[lemma][17][15]15.17}{[1][208][]208}{}{}{}} \newlabel{lem:star-trace}{{15.18}{209}{Star-trace dictionary}{lemma.1079}{}} \newlabel{lem:star-trace@cref}{{[lemma][18][15]15.18}{[1][209][]209}{}{}{}} \newlabel{eq:star-function}{{15.9}{209}{The star function}{equation.1081}{}} \newlabel{eq:star-function@cref}{{[equation][9][15]15.9}{[1][209][]209}{}{}{}} \newlabel{subsec:moving-root-moments}{{15.4.2}{209}{Means and mean squares of the traces \texorpdfstring {$\tau _S$}{tau\_S}}{subsubsection.1082}{}} \newlabel{subsec:moving-root-moments@cref}{{[subsubsection][2][15,4]15.4.2}{[1][209][]209}{}{}{}} \newlabel{lem:moving-root-moments}{{15.19}{209}{Moving-root moments}{lemma.1084}{}} \newlabel{lem:moving-root-moments@cref}{{[lemma][19][15]15.19}{[1][209][]209}{}{}{}} \newlabel{eq:advance:rank-second}{{15.10}{209}{Moving-root moments}{equation.1085}{}} \newlabel{eq:advance:rank-second@cref}{{[equation][10][15]15.10}{[1][209][]209}{}{}{}} \newlabel{eq:advance:rank-first}{{15.11}{209}{Moving-root moments}{equation.1086}{}} \newlabel{eq:advance:rank-first@cref}{{[equation][11][15]15.11}{[1][209][]209}{}{}{}} \newlabel{eq:moving-root-omitted}{{15.12}{210}{Means and mean squares of the traces \texorpdfstring {$\tau _S$}{tau\_S}}{equation.1087}{}} \newlabel{eq:moving-root-omitted@cref}{{[equation][12][15]15.12}{[1][210][]210}{}{}{}} \newlabel{cor:moving-root-uniform}{{15.20}{211}{Uniform constants}{corollary.1089}{}} \newlabel{cor:moving-root-uniform@cref}{{[corollary][20][15]15.20}{[1][211][]211}{}{}{}} \newlabel{cor:moving-root-conditional}{{15.21}{211}{Conditional $L^2$ bound}{corollary.1091}{}} \newlabel{cor:moving-root-conditional@cref}{{[corollary][21][15]15.21}{[1][211][]211}{}{}{}} \newlabel{rem:trace-moment-family}{{15.22}{212}{One family of moments}{remark.1093}{}} \newlabel{rem:trace-moment-family@cref}{{[remark][22][15]15.22}{[1][212][]212}{}{}{}} \newlabel{subsec:advance:ordered-star}{{15.4.3}{212}{Grouping stars by a distinguished free label}{subsubsection.1094}{}} \newlabel{subsec:advance:ordered-star@cref}{{[subsubsection][3][15,4]15.4.3}{[1][212][]212}{}{}{}} \newlabel{def:pinned-law}{{15.23}{212}{Pinned half laws}{definition.1096}{}} \newlabel{def:pinned-law@cref}{{[definition][23][15]15.23}{[1][212][]212}{}{}{}} \newlabel{lem:ordered-orthogonality}{{15.24}{212}{Ordered almost orthogonality}{lemma.1098}{}} \newlabel{lem:ordered-orthogonality@cref}{{[lemma][24][15]15.24}{[1][212][]212}{}{}{}} \newlabel{eq:pivot-sums}{{15.13}{213}{Pivot groups}{equation.1100}{}} \newlabel{eq:pivot-sums@cref}{{[equation][13][15]15.13}{[1][212][]213}{}{}{}} \newlabel{lem:pivot-moments}{{15.25}{213}{Conditional moments of a pivot group}{lemma.1102}{}} \newlabel{lem:pivot-moments@cref}{{[lemma][25][15]15.25}{[1][213][]213}{}{}{}} \newlabel{prop:advance:ordered-star}{{15.26}{214}{Norm of a sum of higher star functions in a fixed vertex order}{proposition.1106}{}} \newlabel{prop:advance:ordered-star@cref}{{[proposition][26][15]15.26}{[1][214][]214}{}{}{}} \newlabel{rem:pivot-order}{{15.27}{214}{The order, and monotonicity in $r$}{remark.1108}{}} \newlabel{rem:pivot-order@cref}{{[remark][27][15]15.27}{[1][214][]214}{}{}{}} \newlabel{lem:wt:stars}{{15.28}{214}{Weighted star marginals in $L^2$}{lemma.1111}{}} \newlabel{lem:wt:stars@cref}{{[lemma][28][15]15.28}{[1][214][]214}{}{}{}} \newlabel{eq:wt:Dst}{{15.14}{214}{Weighted star marginals in $L^2$}{equation.1114}{}} \newlabel{eq:wt:Dst@cref}{{[equation][14][15]15.14}{[1][214][]214}{}{}{}} \newlabel{eq:wt:beta}{{15.15}{214}{Weighted star marginals in $L^2$}{equation.1115}{}} \newlabel{eq:wt:beta@cref}{{[equation][15][15]15.15}{[1][214][]214}{}{}{}} \newlabel{subsec:advance:star-normalizer}{{15.4.4}{216}{The complete-star mean}{subsubsection.1119}{}} \newlabel{subsec:advance:star-normalizer@cref}{{[subsubsection][4][15,4]15.4.4}{[1][216][]216}{}{}{}} \newlabel{lem:star-mean}{{15.29}{216}{The complete-star mean}{lemma.1121}{}} \newlabel{lem:star-mean@cref}{{[lemma][29][15]15.29}{[1][216][]216}{}{}{}} \newlabel{rem:star-mean-scope}{{15.30}{217}{How the mean enters, and what is not done}{remark.1123}{}} \newlabel{rem:star-mean-scope@cref}{{[remark][30][15]15.30}{[1][217][]217}{}{}{}} \newlabel{subsec:second-order-uses}{{15.5}{217}{Where these estimates enter}{subsection.1124}{}} \newlabel{subsec:second-order-uses@cref}{{[subsection][5][15]15.5}{[1][217][]217}{}{}{}} \newlabel{sec:extraction}{{16}{217}{The non-star part of the character expansion and coincident labels}{section.1127}{}} \newlabel{sec:extraction@cref}{{[section][16][]16}{[1][217][]217}{}{}{}} \newlabel{tab:second-order-uses}{{6}{218}{Where the second-order estimates enter}{table.1125}{}} \newlabel{tab:second-order-uses@cref}{{[table][6][]6}{[1][217][]218}{}{}{}} \newlabel{subsec:extraction:partition}{{16.1}{219}{The character expansion and the compressed partition}{subsection.1129}{}} \newlabel{subsec:extraction:partition@cref}{{[subsection][1][16]16.1}{[1][219][]219}{}{}{}} \newlabel{def:extraction:witness}{{16.1}{220}{Witnesses and covers}{definition.1134}{}} \newlabel{def:extraction:witness@cref}{{[definition][1][16]16.1}{[1][220][]220}{}{}{}} \newlabel{lem:advance:compressed-partition}{{16.2}{220}{The compressed partition}{lemma.1139}{}} \newlabel{lem:advance:compressed-partition@cref}{{[lemma][2][16]16.2}{[1][220][]220}{}{}{}} \newlabel{rem:extraction-partition}{{16.3}{221}{Comments on the partition}{remark.1146}{}} \newlabel{rem:extraction-partition@cref}{{[remark][3][16]16.3}{[1][221][]221}{}{}{}} \newlabel{subsec:extraction:kernel}{{16.2}{222}{Bounding a class by two designated pairs}{subsection.1147}{}} \newlabel{subsec:extraction:kernel@cref}{{[subsection][2][16]16.2}{[1][222][]222}{}{}{}} \newlabel{lem:matching:kernel}{{16.4}{222}{Witness kernels}{lemma.1149}{}} \newlabel{lem:matching:kernel@cref}{{[lemma][4][16]16.4}{[1][222][]222}{}{}{}} \newlabel{rem:extraction-kernels}{{16.5}{223}{The witness kernels that occur}{remark.1155}{}} \newlabel{rem:extraction-kernels@cref}{{[remark][5][16]16.5}{[1][223][]223}{}{}{}} \newlabel{subsec:extraction:extraction}{{16.3}{223}{A bound for each class \texorpdfstring {$\mathcal C(P,A)$}{C(P,A)}}{subsection.1156}{}} \newlabel{subsec:extraction:extraction@cref}{{[subsection][3][16]16.3}{[1][223][]223}{}{}{}} \newlabel{def:extraction:records}{{16.6}{223}{Records of a class (extraction data)}{definition.1158}{}} \newlabel{def:extraction:records@cref}{{[definition][6][16]16.6}{[1][223][]223}{}{}{}} \newlabel{lem:extraction-merged-count}{{16.7}{224}{Counts with merged roots}{lemma.1160}{}} \newlabel{lem:extraction-merged-count@cref}{{[lemma][7][16]16.7}{[1][224][]224}{}{}{}} \newlabel{lem:extraction-rows}{{16.8}{224}{Cover rows}{lemma.1162}{}} \newlabel{lem:extraction-rows@cref}{{[lemma][8][16]16.8}{[1][224][]224}{}{}{}} \newlabel{eq:extraction:onevertex}{{16.1}{225}{A bound for each class \texorpdfstring {$\mathcal C(P,A)$}{C(P,A)}}{equation.1163}{}} \newlabel{eq:extraction:onevertex@cref}{{[equation][1][16]16.1}{[1][225][]225}{}{}{}} \newlabel{lem:matching:extractionk}{{16.9}{225}{Grouped extraction with a witness of size $k$}{theorem.1165}{}} \newlabel{lem:matching:extractionk@cref}{{[theorem][9][16]16.9}{[1][225][]225}{}{}{}} \newlabel{eq:extraction:cross-density}{{16.2}{226}{A bound for each class \texorpdfstring {$\mathcal C(P,A)$}{C(P,A)}}{equation.1166}{}} \newlabel{eq:extraction:cross-density@cref}{{[equation][2][16]16.2}{[1][226][]226}{}{}{}} \newlabel{eq:extraction:step4}{{16.3}{226}{A bound for each class \texorpdfstring {$\mathcal C(P,A)$}{C(P,A)}}{equation.1167}{}} \newlabel{eq:extraction:step4@cref}{{[equation][3][16]16.3}{[1][226][]226}{}{}{}} \newlabel{eq:extraction:mbound}{{16.4}{227}{A bound for each class \texorpdfstring {$\mathcal C(P,A)$}{C(P,A)}}{equation.1168}{}} \newlabel{eq:extraction:mbound@cref}{{[equation][4][16]16.4}{[1][227][]227}{}{}{}} \newlabel{rem:extraction-proof}{{16.10}{228}{What the proof uses}{remark.1170}{}} \newlabel{rem:extraction-proof@cref}{{[remark][10][16]16.10}{[1][228][]228}{}{}{}} \newlabel{eq:leaf-factors}{{16.5}{228}{A bound for each class \texorpdfstring {$\mathcal C(P,A)$}{C(P,A)}}{equation.1171}{}} \newlabel{eq:leaf-factors@cref}{{[equation][5][16]16.5}{[1][228][]228}{}{}{}} \newlabel{cor:extraction-leaf}{{16.11}{228}{Leaf bound and nonstar coefficients}{corollary.1173}{}} \newlabel{cor:extraction-leaf@cref}{{[corollary][11][16]16.11}{[1][228][]228}{}{}{}} \newlabel{eq:monotone-signature}{{16.6}{229}{Leaf bound and nonstar coefficients}{equation.1175}{}} \newlabel{eq:monotone-signature@cref}{{[equation][6][16]16.6}{[1][229][]229}{}{}{}} \newlabel{lem:logconvex-coefficients}{{16.12}{229}{Log-convex nonstar coefficients}{lemma.1178}{}} \newlabel{lem:logconvex-coefficients@cref}{{[lemma][12][16]16.12}{[1][229][]229}{}{}{}} \newlabel{lem:cover:order}{{16.13}{230}{An order with a bounded weighted extension sum}{lemma.1180}{}} \newlabel{lem:cover:order@cref}{{[lemma][13][16]16.13}{[1][230][]230}{}{}{}} \newlabel{cor:extraction-compressed}{{16.14}{230}{Compressed classes, log-linear form}{corollary.1182}{}} \newlabel{cor:extraction-compressed@cref}{{[corollary][14][16]16.14}{[1][230][]230}{}{}{}} \newlabel{subsec:extraction:coincidences}{{16.4}{231}{Ordered coincidences}{subsection.1183}{}} \newlabel{subsec:extraction:coincidences@cref}{{[subsection][4][16]16.4}{[1][231][]231}{}{}{}} \newlabel{lem:oct24-collision}{{16.15}{231}{Ordered coincidence bound}{lemma.1185}{}} \newlabel{lem:oct24-collision@cref}{{[lemma][15][16]16.15}{[1][231][]231}{}{}{}} \newlabel{eq:oct24-collision}{{16.7}{232}{Ordered coincidence bound}{equation.1188}{}} \newlabel{eq:oct24-collision@cref}{{[equation][7][16]16.7}{[1][232][]232}{}{}{}} \newlabel{eq:collision-natural}{{16.8}{232}{Ordered coincidence bound}{equation.1191}{}} \newlabel{eq:collision-natural@cref}{{[equation][8][16]16.8}{[1][232][]232}{}{}{}} \newlabel{rem:collision-fixed-order}{{16.16}{233}{Why the coincident vertices are labelled first}{remark.1194}{}} \newlabel{rem:collision-fixed-order@cref}{{[remark][16][16]16.16}{[1][233][]233}{}{}{}} \newlabel{cor:soft-kernels}{{16.17}{233}{Soft cross factors}{corollary.1197}{}} \newlabel{cor:soft-kernels@cref}{{[corollary][17][16]16.17}{[1][233][]233}{}{}{}} \newlabel{cor:incident-weights}{{16.18}{234}{Incident weights at coincident vertices}{corollary.1202}{}} \newlabel{cor:incident-weights@cref}{{[corollary][18][16]16.18}{[1][234][]234}{}{}{}} \newlabel{lem:signed-collisions}{{16.19}{235}{Sign-incompatible collision strata}{lemma.1204}{}} \newlabel{lem:signed-collisions@cref}{{[lemma][19][16]16.19}{[1][235][]235}{}{}{}} \newlabel{subsec:push:pinnedremainder}{{16.5}{235}{Conditional laws given fixed labels}{subsection.1205}{}} \newlabel{subsec:push:pinnedremainder@cref}{{[subsection][5][16]16.5}{[1][235][]235}{}{}{}} \newlabel{prop:pinned-extraction}{{16.20}{236}{Pinned compressed classes}{proposition.1208}{}} \newlabel{prop:pinned-extraction@cref}{{[proposition][20][16]16.20}{[1][236][]236}{}{}{}} \newlabel{eq:push:pinnedclass}{{16.9}{236}{Pinned compressed classes}{equation.1209}{}} \newlabel{eq:push:pinnedclass@cref}{{[equation][9][16]16.9}{[1][236][]236}{}{}{}} \newlabel{prop:pinned-collision}{{16.21}{237}{Pinned coincidences}{proposition.1211}{}} \newlabel{prop:pinned-collision@cref}{{[proposition][21][16]16.21}{[1][237][]237}{}{}{}} \newlabel{prop:conditional-star}{{16.22}{238}{Star matrix under pinned product laws}{proposition.1214}{}} \newlabel{prop:conditional-star@cref}{{[proposition][22][16]16.22}{[1][238][]238}{}{}{}} \newlabel{eq:conditional-star-gate}{{16.10}{238}{Star matrix under pinned product laws}{equation.1216}{}} \newlabel{eq:conditional-star-gate@cref}{{[equation][10][16]16.10}{[1][238][]238}{}{}{}} \newlabel{lem:joint-rows}{{16.23}{240}{Joint fold and matching rows}{lemma.1221}{}} \newlabel{lem:joint-rows@cref}{{[lemma][23][16]16.23}{[1][240][]240}{}{}{}} \newlabel{eq:joint-gate}{{16.11}{241}{Joint fold and matching rows}{equation.1223}{}} \newlabel{eq:joint-gate@cref}{{[equation][11][16]16.11}{[1][241][]241}{}{}{}} \newlabel{cor:joint-row-split}{{16.24}{242}{The joint fluctuation in a positive row}{corollary.1227}{}} \newlabel{cor:joint-row-split@cref}{{[corollary][24][16]16.24}{[1][242][]242}{}{}{}} \newlabel{lem:joint-potential}{{16.25}{243}{Positive potentials}{lemma.1229}{}} \newlabel{lem:joint-potential@cref}{{[lemma][25][16]16.25}{[1][243][]243}{}{}{}} \newlabel{eq:joint-potential-gate}{{16.12}{243}{Positive potentials}{equation.1230}{}} \newlabel{eq:joint-potential-gate@cref}{{[equation][12][16]16.12}{[1][243][]243}{}{}{}} \newlabel{rem:pinned-instances}{{16.26}{243}{The pinned rows of the construction}{remark.1232}{}} \newlabel{rem:pinned-instances@cref}{{[remark][26][16]16.26}{[1][243][]243}{}{}{}} \newlabel{sec:completion-repair}{{17}{245}{Making a graph law reflection positive, and replacing a law at fixed marginals}{section.1235}{}} \newlabel{sec:completion-repair@cref}{{[section][17][]17}{[1][245][]245}{}{}{}} \newlabel{subsec:chamber-geometry}{{17.1}{246}{How records sit inside chambers (supports and symmetries)}{subsection.1240}{}} \newlabel{subsec:chamber-geometry@cref}{{[subsection][1][17]17.1}{[1][246][]246}{}{}{}} \newlabel{def:patterns}{{17.1}{246}{Patterns and types}{definition.1242}{}} \newlabel{def:patterns@cref}{{[definition][1][17]17.1}{[1][246][]246}{}{}{}} \newlabel{lem:record:fold-identification}{{17.2}{246}{Chamber geometry of the records}{lemma.1246}{}} \newlabel{lem:record:fold-identification@cref}{{[lemma][2][17]17.2}{[1][246][]246}{}{}{}} \newlabel{tab:corner}{{7}{247}{The halves of $\omega \circ \phi $ at $\vartheta _0$, for $\omega =(\omega _0,\omega _1,\omega _2)$, and the corners $\mathcal U=\{(b,y,y)\colon y\ne b\}$, $\mathcal V=\{(y,y,b)\colon y\ne b\}$, $\mathcal Z=\{(b,b,b)\}$ of $\mathfrak X^{H_0}$ in which they lie when the labels $\omega _o$ that occur are distinct. In the position column $\mathcal A\to \mathcal B$ means that the plus half lies in $\mathcal A$ and the reflected half in $\mathcal B$}{table.1243}{}} \newlabel{tab:corner@cref}{{[table][7][]7}{[1][246][]247}{}{}{}} \newlabel{tab:reflection}{{8}{247}{Precomposition with the generators of $\mathcal G_6$: $E_s\circ \alpha =\psi _{s,\alpha }\circ E_s$, where $(0\ 1\ 2)$ is the cycle $0\mapsto 1\mapsto 2\mapsto 0$}{table.1244}{}} \newlabel{tab:reflection@cref}{{[table][8][]8}{[1][246][]247}{}{}{}} \newlabel{subsec:five-type}{{17.2}{248}{The five-type completion}{subsection.1253}{}} \newlabel{subsec:five-type@cref}{{[subsection][2][17]17.2}{[1][248][]248}{}{}{}} \newlabel{def:five-type-datum}{{17.3}{249}{Five-type datum}{definition.1255}{}} \newlabel{def:five-type-datum@cref}{{[definition][3][17]17.3}{[1][248][]249}{}{}{}} \newlabel{def:two-coordinate-five-type}{{17.4}{249}{Two coordinates}{definition.1262}{}} \newlabel{def:two-coordinate-five-type@cref}{{[definition][4][17]17.4}{[1][249][]249}{}{}{}} \newlabel{lem:five-type}{{17.5}{249}{Five-type completion}{lemma.1264}{}} \newlabel{lem:five-type@cref}{{[lemma][5][17]17.5}{[1][249][]249}{}{}{}} \newlabel{cor:joint-completion-blocks}{{17.6}{253}{Joint rows of a block}{corollary.1272}{}} \newlabel{cor:joint-completion-blocks@cref}{{[corollary][6][17]17.6}{[1][253][]253}{}{}{}} \newlabel{rem:five-type-fold-data}{{17.7}{254}{Fold data from marginal densities}{remark.1274}{}} \newlabel{rem:five-type-fold-data@cref}{{[remark][7][17]17.7}{[1][254][]254}{}{}{}} \newlabel{rem:five-type-model}{{17.8}{254}{The model computation and its ancestors}{remark.1276}{}} \newlabel{rem:five-type-model@cref}{{[remark][8][17]17.8}{[1][254][]254}{}{}{}} \newlabel{rem:five-type-certificates}{{17.9}{255}{How the completions are certified}{remark.1278}{}} \newlabel{rem:five-type-certificates@cref}{{[remark][9][17]17.9}{[1][255][]255}{}{}{}} \newlabel{rem:fold-pairing}{{17.10}{255}{Fold pairing}{remark.1280}{}} \newlabel{rem:fold-pairing@cref}{{[remark][10][17]17.10}{[1][255][]255}{}{}{}} \newlabel{subsec:polarization}{{17.3}{255}{Polarization: dominating two summands by two others}{subsection.1281}{}} \newlabel{subsec:polarization@cref}{{[subsection][3][17]17.3}{[1][255][]255}{}{}{}} \newlabel{lem:tr:polarization}{{17.11}{255}{Polarization}{lemma.1283}{}} \newlabel{lem:tr:polarization@cref}{{[lemma][11][17]17.11}{[1][255][]255}{}{}{}} \newlabel{eq:polarization}{{17.1}{255}{Polarization}{equation.1284}{}} \newlabel{eq:polarization@cref}{{[equation][1][17]17.1}{[1][255][]255}{}{}{}} \newlabel{rem:polarization-uses}{{17.12}{257}{Where polarization is used}{remark.1290}{}} \newlabel{rem:polarization-uses@cref}{{[remark][12][17]17.12}{[1][257][]257}{}{}{}} \newlabel{subsec:additive-repair}{{17.4}{257}{Reweighting to prescribed marginals}{subsection.1291}{}} \newlabel{subsec:additive-repair@cref}{{[subsection][4][17]17.4}{[1][257][]257}{}{}{}} \newlabel{lem:record:additive-cancellation}{{17.13}{257}{Centred norm of an additive reweighting}{lemma.1293}{}} \newlabel{lem:record:additive-cancellation@cref}{{[lemma][13][17]17.13}{[1][257][]257}{}{}{}} \newlabel{lem:tr:repair}{{17.14}{258}{Additive marginal repair}{lemma.1295}{}} \newlabel{lem:tr:repair@cref}{{[lemma][14][17]17.14}{[1][258][]258}{}{}{}} \newlabel{rem:repair-forms}{{17.15}{259}{Blocks and the certified forms}{remark.1304}{}} \newlabel{rem:repair-forms@cref}{{[remark][15][17]17.15}{[1][259][]259}{}{}{}} \newlabel{lem:record:centered-correction}{{17.16}{260}{Centred additive correction}{lemma.1306}{}} \newlabel{lem:record:centered-correction@cref}{{[lemma][16][17]17.16}{[1][260][]260}{}{}{}} \newlabel{cor:markov-completion}{{17.17}{261}{Completion by mixing in a coupling of the target marginals}{corollary.1311}{}} \newlabel{cor:markov-completion@cref}{{[corollary][17][17]17.17}{[1][261][]261}{}{}{}} \newlabel{sec:design}{{18}{262}{Overview of the construction verifying (CP0)--(CP8)}{section.1313}{}} \newlabel{sec:design@cref}{{[section][18][]18}{[1][262][]262}{}{}{}} \newlabel{subsec:design-parameters}{{18.1}{262}{The baseline numerical parameters}{subsection.1315}{}} \newlabel{subsec:design-parameters@cref}{{[subsection][1][18]18.1}{[1][262][]262}{}{}{}} \newlabel{def:record:parameters}{{18.1}{262}{Parameters}{definition.1317}{}} \newlabel{def:record:parameters@cref}{{[definition][1][18]18.1}{[1][262][]262}{}{}{}} \newlabel{subsec:front6:construction}{{18.2}{264}{The six queries \texorpdfstring {$\mathcal E_6$}{E\_6} and the twelve pairs in projections}{subsection.1328}{}} \newlabel{subsec:front6:construction@cref}{{[subsection][2][18]18.2}{[1][264][]264}{}{}{}} \newlabel{subsec:front12:construction}{{18.2}{265}{The twelve-query superset}{remark.1330}{}} \newlabel{subsec:front12:construction@cref}{{[remark][2][18]18.2}{[1][265][]265}{}{}{}} \newlabel{subsec:design-laws}{{18.3}{265}{Which graph law is used in each prime range}{subsection.1331}{}} \newlabel{subsec:design-laws@cref}{{[subsection][3][18]18.3}{[1][265][]265}{}{}{}} \newlabel{def:construction}{{18.3}{265}{The construction}{definition.1333}{}} \newlabel{def:construction@cref}{{[definition][3][18]18.3}{[1][265][]265}{}{}{}} \gdef \LT@iii {\LT@entry {1}{77.55461pt}\LT@entry {1}{139.46011pt}\LT@entry {1}{103.89418pt}\LT@entry {1}{125.92421pt}} \newlabel{tab:ranges}{{9}{267}{The ranges of primes}{table.lt.9}{}} \newlabel{tab:ranges@cref}{{[table][9][]9}{[1][266][]267}{}{}{}} \gdef \LT@iv {\LT@entry {1}{103.16191pt}\LT@entry {1}{135.19194pt}\LT@entry {1}{113.85237pt}\LT@entry {1}{94.626pt}} \newlabel{subsec:design-admissibility}{{18.4}{268}{Three uses of ``admissible'', and why each holds}{subsection.1341}{}} \newlabel{subsec:design-admissibility@cref}{{[subsection][4][18]18.4}{[1][268][]268}{}{}{}} \newlabel{tab:admissibility}{{10}{268}{The laws of the construction and their admissibility}{table.lt.10}{}} \newlabel{tab:admissibility@cref}{{[table][10][]10}{[1][268][]268}{}{}{}} \newlabel{subsec:design-table}{{18.5}{269}{Where the hypotheses are verified (guide to Part~V)}{subsection.1343}{}} \newlabel{subsec:design-table@cref}{{[subsection][5][18]18.5}{[1][269][]269}{}{}{}} \newlabel{sec:frontier:iidprefix}{{19}{270}{Primes \texorpdfstring {$p\equiv 1\pmod 4$}{p = 1 (mod 4)}: independent labels from a random square clique}{section.1346}{}} \newlabel{sec:frontier:iidprefix@cref}{{[section][19][]19}{[1][270][]270}{}{}{}} \newlabel{subsec:clique-law}{{19.1}{270}{The square-clique law}{subsection.1348}{}} \newlabel{subsec:clique-law@cref}{{[subsection][1][19]19.1}{[1][270][]270}{}{}{}} \newlabel{def:clique-law}{{19.1}{270}{The square-clique law}{definition.1350}{}} \newlabel{def:clique-law@cref}{{[definition][1][19]19.1}{[1][270][]270}{}{}{}} \newlabel{subsec:clique-local}{{19.2}{271}{Reflection positivity and forcing except for coincidences}{subsection.1351}{}} \newlabel{subsec:clique-local@cref}{{[subsection][2][19]19.2}{[1][271][]271}{}{}{}} \newlabel{lem:frontier:iidlocal}{{19.2}{271}{The square-clique law}{lemma.1353}{}} \newlabel{lem:frontier:iidlocal@cref}{{[lemma][2][19]19.2}{[1][271][]271}{}{}{}} \newlabel{subsec:clique-price}{{19.3}{272}{Price of deleting coincident labels}{subsection.1360}{}} \newlabel{subsec:clique-price@cref}{{[subsection][3][19]19.3}{[1][272][]272}{}{}{}} \newlabel{lem:frontier:iidenergy}{{19.3}{272}{The price of the prefix}{lemma.1362}{}} \newlabel{lem:frontier:iidenergy@cref}{{[lemma][3][19]19.3}{[1][272][]272}{}{}{}} \newlabel{rem:prefix-digits}{{19.4}{273}{The allowance and the number of digit pairs}{remark.1368}{}} \newlabel{rem:prefix-digits@cref}{{[remark][4][19]19.4}{[1][273][]273}{}{}{}} \newlabel{sec:middle-reference}{{20}{274}{Middle primes I: blocks and spectral bounds for the twelve-label law}{section.1371}{}} \newlabel{sec:middle-reference@cref}{{[section][20][]20}{[1][274][]274}{}{}{}} \newlabel{subsec:record:middle_blocks}{{20.1}{274}{Middle blocks with \texorpdfstring {$\sum \log p\le 570$}{sum log p <= 570} and their degree sums}{subsection.1373}{}} \newlabel{subsec:record:middle_blocks@cref}{{[subsection][1][20]20.1}{[1][274][]274}{}{}{}} \newlabel{def:record:exact-blocks}{{20.1}{275}{Exact log-budget blocks}{definition.1375}{}} \newlabel{def:record:exact-blocks@cref}{{[definition][1][20]20.1}{[1][275][]275}{}{}{}} \newlabel{rem:middle-restarts}{{20.2}{276}{Restarts and fixed cardinality}{remark.1381}{}} \newlabel{rem:middle-restarts@cref}{{[remark][2][20]20.2}{[1][276][]276}{}{}{}} \newlabel{lem:record:local-domain}{{20.3}{276}{Domain of the local laws}{lemma.1383}{}} \newlabel{lem:record:local-domain@cref}{{[lemma][3][20]20.3}{[1][276][]276}{}{}{}} \newlabel{lem:record:block-charge}{{20.4}{277}{Block charges}{lemma.1388}{}} \newlabel{lem:record:block-charge@cref}{{[lemma][4][20]20.4}{[1][277][]277}{}{}{}} \newlabel{eq:record:cell-charge}{{20.1}{277}{Block charges}{equation.1390}{}} \newlabel{eq:record:cell-charge@cref}{{[equation][1][20]20.1}{[1][277][]277}{}{}{}} \newlabel{cor:positive-charge-functional}{{20.5}{278}{One positive functional for all charge degrees}{corollary.1393}{}} \newlabel{cor:positive-charge-functional@cref}{{[corollary][5][20]20.5}{[1][278][]278}{}{}{}} \newlabel{lem:record:lower-start-sums}{{20.6}{278}{Lower start sums}{lemma.1395}{}} \newlabel{lem:record:lower-start-sums@cref}{{[lemma][6][20]20.6}{[1][278][]278}{}{}{}} \newlabel{lem:piece-caps}{{20.7}{279}{Piece caps}{lemma.1399}{}} \newlabel{lem:piece-caps@cref}{{[lemma][7][20]20.7}{[1][279][]279}{}{}{}} \newlabel{rem:record:middle-scope}{{20.8}{279}{What rests on the explicit Chebyshev bound}{remark.1401}{}} \newlabel{rem:record:middle-scope@cref}{{[remark][8][20]20.8}{[1][279][]279}{}{}{}} \newlabel{subsec:middle-pairs}{{20.2}{279}{Ordered pairs at \texorpdfstring {$p\equiv 3\pmod 4$}{p = 3 (mod 4)}}{subsection.1402}{}} \newlabel{subsec:middle-pairs@cref}{{[subsection][2][20]20.2}{[1][279][]279}{}{}{}} \newlabel{lem:record:class-three}{{20.9}{279}{Class-three middle pairs}{lemma.1404}{}} \newlabel{lem:record:class-three@cref}{{[lemma][9][20]20.9}{[1][279][]279}{}{}{}} \newlabel{rem:middle-class-three}{{20.10}{280}{Why the middle range is class three}{remark.1409}{}} \newlabel{rem:middle-class-three@cref}{{[remark][10][20]20.10}{[1][280][]280}{}{}{}} \newlabel{subsec:push:layer12spectral}{{20.3}{280}{The twelve-label graphs and bounds \texorpdfstring {$-gp^{-1/2}I\preceq A_p\preceq (1+c^+/p)I$}{-g p\textasciicircum (-1/2) I <= A\_p <= (1+c+/p) I}}{subsection.1410}{}} \newlabel{subsec:push:layer12spectral@cref}{{[subsection][3][20]20.3}{[1][280][]280}{}{}{}} \newlabel{lem:layer12-geometry}{{20.11}{280}{Twelve-label geometry}{lemma.1412}{}} \newlabel{lem:layer12-geometry@cref}{{[lemma][11][20]20.11}{[1][280][]280}{}{}{}} \newlabel{lem:layer12-caps}{{20.12}{281}{Twelve-label caps}{lemma.1418}{}} \newlabel{lem:layer12-caps@cref}{{[lemma][12][20]20.12}{[1][281][]281}{}{}{}} \newlabel{cert:layer12-grid}{{20.13}{281}{The twelve-label grids}{certificate.1422}{}} \newlabel{cert:layer12-grid@cref}{{[certificate][13][20]20.13}{[1][281][]281}{}{}{}} \newlabel{subsec:middle-l20}{{20.4}{282}{The chamber symmetry L20 for the uniform principal law}{subsection.1423}{}} \newlabel{subsec:middle-l20@cref}{{[subsection][4][20]20.4}{[1][282][]282}{}{}{}} \newlabel{eq:l20-cross-matrix}{{20.2}{283}{The chamber symmetry L20 for the uniform principal law}{equation.1424}{}} \newlabel{eq:l20-cross-matrix@cref}{{[equation][2][20]20.2}{[1][282][]283}{}{}{}} \newlabel{lem:l20-star-matrix}{{20.14}{283}{Complete stars of L20}{lemma.1426}{}} \newlabel{lem:l20-star-matrix@cref}{{[lemma][14][20]20.14}{[1][283][]283}{}{}{}} \newlabel{eq:l20-rank4-operator}{{20.3}{283}{Complete stars of L20}{equation.1430}{}} \newlabel{eq:l20-rank4-operator@cref}{{[equation][3][20]20.3}{[1][283][]283}{}{}{}} \newlabel{prop:l20-completion}{{20.15}{284}{Translation sectors}{proposition.1432}{}} \newlabel{prop:l20-completion@cref}{{[proposition][15][20]20.15}{[1][284][]284}{}{}{}} \newlabel{eq:l20-caps}{{20.4}{285}{Translation sectors}{equation.1433}{}} \newlabel{eq:l20-caps@cref}{{[equation][4][20]20.4}{[1][285][]285}{}{}{}} \newlabel{prop:l20-rank4}{{20.16}{285}{Gram bounds for the four L20 star features}{proposition.1435}{}} \newlabel{prop:l20-rank4@cref}{{[proposition][16][20]20.16}{[1][285][]285}{}{}{}} \newlabel{prop:l20-rectangular}{{20.17}{287}{The soft L20 kernel as a swapped rectangle product}{proposition.1441}{}} \newlabel{prop:l20-rectangular@cref}{{[proposition][17][20]20.17}{[1][287][]287}{}{}{}} \newlabel{eq:l20-rectangle}{{20.5}{287}{The soft L20 kernel as a swapped rectangle product}{equation.1444}{}} \newlabel{eq:l20-rectangle@cref}{{[equation][5][20]20.5}{[1][287][]287}{}{}{}} \newlabel{eq:l20-swap}{{20.6}{287}{The soft L20 kernel as a swapped rectangle product}{equation.1446}{}} \newlabel{eq:l20-swap@cref}{{[equation][6][20]20.6}{[1][287][]287}{}{}{}} \newlabel{lem:rectangle-mellin}{{20.18}{288}{Two-sided bounds for the squared cubic trace $H_u$}{lemma.1450}{}} \newlabel{lem:rectangle-mellin@cref}{{[lemma][18][20]20.18}{[1][288][]288}{}{}{}} \newlabel{thm:rectangle-gram}{{20.19}{289}{The centred accepting rectangle}{theorem.1452}{}} \newlabel{thm:rectangle-gram@cref}{{[theorem][19][20]20.19}{[1][289][]289}{}{}{}} \newlabel{eq:rectangle-gram-cap}{{20.7}{289}{The centred accepting rectangle}{equation.1453}{}} \newlabel{eq:rectangle-gram-cap@cref}{{[equation][7][20]20.7}{[1][289][]289}{}{}{}} \newlabel{eq:rectangle-gram-polynomial}{{20.8}{289}{Bounding the centred remainder through its Gram}{equation.1454}{}} \newlabel{eq:rectangle-gram-polynomial@cref}{{[equation][8][20]20.8}{[1][289][]289}{}{}{}} \newlabel{prop:l20-pair-gap}{{20.20}{292}{Sharper bound for the centred rectangle, using the gap $30q-\ell _g^2$}{proposition.1456}{}} \newlabel{prop:l20-pair-gap@cref}{{[proposition][20][20]20.20}{[1][292][]292}{}{}{}} \newlabel{prop:l20-collisions}{{20.21}{293}{Collisions with the core--pair weights of the proof; the caps of L20}{proposition.1458}{}} \newlabel{prop:l20-collisions@cref}{{[proposition][21][20]20.21}{[1][292][]293}{}{}{}} \newlabel{cert:l20-grid}{{20.22}{294}{The L20 grid}{certificate.1462}{}} \newlabel{cert:l20-grid@cref}{{[certificate][22][20]20.22}{[1][294][]294}{}{}{}} \newlabel{sec:positive-roots}{{21}{295}{Middle primes II: reweighting the principal law on seven intervals}{section.1465}{}} \newlabel{sec:positive-roots@cref}{{[section][21][]21}{[1][295][]295}{}{}{}} \newlabel{subsec:positive-root-law}{{21.1}{296}{The tilted law \texorpdfstring {$\Gamma _{p,\ulaw }$}{Gamma\_(p,u)}}{subsection.1467}{}} \newlabel{subsec:positive-root-law@cref}{{[subsection][1][21]21.1}{[1][296][]296}{}{}{}} \newlabel{def:positive-root}{{21.1}{296}{Positive roots}{definition.1469}{}} \newlabel{def:positive-root@cref}{{[definition][1][21]21.1}{[1][296][]296}{}{}{}} \newlabel{eq:positive-root}{{21.1}{296}{Positive roots}{equation.1470}{}} \newlabel{eq:positive-root@cref}{{[equation][1][21]21.1}{[1][296][]296}{}{}{}} \newlabel{lem:positive-root-properties}{{21.2}{297}{Properties of the positive roots}{lemma.1472}{}} \newlabel{lem:positive-root-properties@cref}{{[lemma][2][21]21.2}{[1][297][]297}{}{}{}} \newlabel{subsec:positive-root-chamber}{{21.2}{298}{The chamber symmetry for the tilted law}{subsection.1476}{}} \newlabel{subsec:positive-root-chamber@cref}{{[subsection][2][21]21.2}{[1][297][]298}{}{}{}} \newlabel{eq:root-score-feature}{{21.2}{299}{The scores as kernels}{equation.1479}{}} \newlabel{eq:root-score-feature@cref}{{[equation][2][21]21.2}{[1][299][]299}{}{}{}} \newlabel{lem:root-pair-matrix}{{21.3}{299}{The pair-feature matrix of a tilt}{lemma.1481}{}} \newlabel{lem:root-pair-matrix@cref}{{[lemma][3][21]21.3}{[1][299][]299}{}{}{}} \newlabel{eq:root-cubic}{{21.3}{299}{The pair-feature matrix of a tilt}{equation.1482}{}} \newlabel{eq:root-cubic@cref}{{[equation][3][21]21.3}{[1][299][]299}{}{}{}} \newlabel{lem:root-square}{{21.4}{300}{Square of a score on the rectangle}{lemma.1484}{}} \newlabel{lem:root-square@cref}{{[lemma][4][21]21.4}{[1][300][]300}{}{}{}} \newlabel{lem:root-linear}{{21.5}{302}{Linear root trace}{lemma.1487}{}} \newlabel{lem:root-linear@cref}{{[lemma][5][21]21.5}{[1][302][]302}{}{}{}} \newlabel{lem:root-normalization}{{21.6}{303}{Normalization, marginal and conditional prices}{lemma.1489}{}} \newlabel{lem:root-normalization@cref}{{[lemma][6][21]21.6}{[1][303][]303}{}{}{}} \newlabel{prop:root-chamber}{{21.7}{305}{The chamber cut of a positive root}{proposition.1494}{}} \newlabel{prop:root-chamber@cref}{{[proposition][7][21]21.7}{[1][305][]305}{}{}{}} \newlabel{subsec:positive-root-layer}{{21.3}{307}{The layer-flip symmetry \texorpdfstring {$\iota $}{iota} for the tilted law}{subsection.1495}{}} \newlabel{subsec:positive-root-layer@cref}{{[subsection][3][21]21.3}{[1][307][]307}{}{}{}} \newlabel{lem:native-pair-linear}{{21.8}{308}{Inserting an opposite-base-pair score into the soft kernel}{lemma.1502}{}} \newlabel{lem:native-pair-linear@cref}{{[lemma][8][21]21.8}{[1][308][]308}{}{}{}} \newlabel{prop:root-layer}{{21.9}{309}{The layer cut of a positive root}{proposition.1504}{}} \newlabel{prop:root-layer@cref}{{[proposition][9][21]21.9}{[1][309][]309}{}{}{}} \newlabel{imp:local:protected-section}{{21.4}{310}{Isolating collision terms on two explicit subspaces}{subsection.1506}{}} \newlabel{imp:local:protected-section@cref}{{[subsection][4][21]21.4}{[1][310][]310}{}{}{}} \newlabel{imp:local:pin-projections}{{21.10}{311}{Compression of the constant kernels at pinned labels}{lemma.1508}{}} \newlabel{imp:local:pin-projections@cref}{{[lemma][10][21]21.10}{[1][311][]311}{}{}{}} \newlabel{eq:merge-local-I-14}{{21.4}{312}{Compression of the constant kernels at pinned labels}{equation.1509}{}} \newlabel{eq:merge-local-I-14@cref}{{[equation][4][21]21.4}{[1][312][]312}{}{}{}} \newlabel{imp:local:finite-collision-section}{{21.5}{312}{A finite collision bound for the uniform law}{subsection.1510}{}} \newlabel{imp:local:finite-collision-section@cref}{{[subsection][5][21]21.5}{[1][312][]312}{}{}{}} \newlabel{eq:merge-local-I-15}{{21.5}{312}{A finite collision bound for the uniform law}{equation.1511}{}} \newlabel{eq:merge-local-I-15@cref}{{[equation][5][21]21.5}{[1][312][]312}{}{}{}} \newlabel{imp:local:collision-gap}{{21.11}{312}{Finite bound for the collision term on the two protected subspaces}{proposition.1513}{}} \newlabel{imp:local:collision-gap@cref}{{[proposition][11][21]21.11}{[1][312][]312}{}{}{}} \newlabel{eq:merge-local-I-16}{{21.6}{312}{Finite bound for the collision term on the two protected subspaces}{equation.1514}{}} \newlabel{eq:merge-local-I-16@cref}{{[equation][6][21]21.6}{[1][312][]312}{}{}{}} \newlabel{eq:merge-local-I-17}{{21.7}{312}{Finite bound for the collision term on the two protected subspaces}{equation.1515}{}} \newlabel{eq:merge-local-I-17@cref}{{[equation][7][21]21.7}{[1][312][]312}{}{}{}} \newlabel{eq:merge-local-I-18}{{21.8}{313}{Finite bound for the collision term on the two protected subspaces}{equation.1516}{}} \newlabel{eq:merge-local-I-18@cref}{{[equation][8][21]21.8}{[1][312][]313}{}{}{}} \newlabel{imp:env:gap-section}{{21.6}{314}{Allocating the pair-square remainder across a spectral gap}{subsection.1517}{}} \newlabel{imp:env:gap-section@cref}{{[subsection][6][21]21.6}{[1][314][]314}{}{}{}} \newlabel{imp:env:conditional-square}{{21.9}{314}{Allocating the pair-square remainder across a spectral gap}{equation.1518}{}} \newlabel{imp:env:conditional-square@cref}{{[equation][9][21]21.9}{[1][314][]314}{}{}{}} \newlabel{imp:env:pair-residual}{{21.12}{314}{The pair-square residual}{lemma.1520}{}} \newlabel{imp:env:pair-residual@cref}{{[lemma][12][21]21.12}{[1][314][]314}{}{}{}} \newlabel{imp:env:finite-gap-chamber}{{21.13}{315}{Finite chamber-cut price for the pair-square law, with the gap bound}{proposition.1522}{}} \newlabel{imp:env:finite-gap-chamber@cref}{{[proposition][13][21]21.13}{[1][315][]315}{}{}{}} \newlabel{imp:env:physical-gap}{{21.10}{316}{Finite chamber-cut price for the pair-square law, with the gap bound}{equation.1523}{}} \newlabel{imp:env:physical-gap@cref}{{[equation][10][21]21.10}{[1][316][]316}{}{}{}} \newlabel{imp:env:physical-interpolation}{{21.14}{317}{Interpolation after physical normalization}{corollary.1525}{}} \newlabel{imp:env:physical-interpolation@cref}{{[corollary][14][21]21.14}{[1][317][]317}{}{}{}} \newlabel{imp:env:layer-section}{{21.7}{317}{Retaining the constant coefficient at the layer cut}{subsection.1526}{}} \newlabel{imp:env:layer-section@cref}{{[subsection][7][21]21.7}{[1][317][]317}{}{}{}} \newlabel{imp:env:layer-resummation}{{21.15}{317}{Layer-cut remainder, summed without expanding all monomials}{proposition.1528}{}} \newlabel{imp:env:layer-resummation@cref}{{[proposition][15][21]21.15}{[1][317][]317}{}{}{}} \newlabel{imp:local:star-product}{{21.16}{318}{Higher-star products}{lemma.1531}{}} \newlabel{imp:local:star-product@cref}{{[lemma][16][21]21.16}{[1][318][]318}{}{}{}} \newlabel{eq:merge-local-I-4}{{21.11}{318}{Higher-star products}{equation.1532}{}} \newlabel{eq:merge-local-I-4@cref}{{[equation][11][21]21.11}{[1][318][]318}{}{}{}} \newlabel{eq:merge-local-I-5}{{21.12}{319}{Supports of the \texorpdfstring {$39$}{39}-trace law}{equation.1533}{}} \newlabel{eq:merge-local-I-5@cref}{{[equation][12][21]21.12}{[1][318][]319}{}{}{}} \newlabel{imp:local:filtered-coherent}{{21.9}{319}{The \texorpdfstring {$39$}{39}-trace law at every sorting cut}{subsection.1534}{}} \newlabel{imp:local:filtered-coherent@cref}{{[subsection][9][21]21.9}{[1][319][]319}{}{}{}} \newlabel{eq:merge-local-I-19}{{21.13}{319}{The \texorpdfstring {$39$}{39}-trace law at every sorting cut}{equation.1535}{}} \newlabel{eq:merge-local-I-19@cref}{{[equation][13][21]21.13}{[1][319][]319}{}{}{}} \newlabel{eq:merge-local-I-20}{{21.14}{319}{The \texorpdfstring {$39$}{39}-trace law at every sorting cut}{equation.1536}{}} \newlabel{eq:merge-local-I-20@cref}{{[equation][14][21]21.14}{[1][319][]319}{}{}{}} \newlabel{eq:merge-local-I-21}{{21.15}{319}{The \texorpdfstring {$39$}{39}-trace law at every sorting cut}{equation.1537}{}} \newlabel{eq:merge-local-I-21@cref}{{[equation][15][21]21.15}{[1][319][]319}{}{}{}} \newlabel{eq:merge-local-I-23}{{21.16}{320}{The \texorpdfstring {$39$}{39}-trace law at every sorting cut}{equation.1538}{}} \newlabel{eq:merge-local-I-23@cref}{{[equation][16][21]21.16}{[1][320][]320}{}{}{}} \newlabel{eq:merge-local-I-24}{{21.17}{320}{The \texorpdfstring {$39$}{39}-trace law at every sorting cut}{equation.1539}{}} \newlabel{eq:merge-local-I-24@cref}{{[equation][17][21]21.17}{[1][320][]320}{}{}{}} \newlabel{eq:merge-local-I-25}{{21.18}{320}{The \texorpdfstring {$39$}{39}-trace law at every sorting cut}{equation.1540}{}} \newlabel{eq:merge-local-I-25@cref}{{[equation][18][21]21.18}{[1][320][]320}{}{}{}} \newlabel{eq:merge-local-I-26}{{21.19}{320}{The \texorpdfstring {$39$}{39}-trace law at every sorting cut}{equation.1541}{}} \newlabel{eq:merge-local-I-26@cref}{{[equation][19][21]21.19}{[1][320][]320}{}{}{}} \newlabel{eq:merge-local-I-27}{{21.20}{320}{The \texorpdfstring {$39$}{39}-trace law at every sorting cut}{equation.1542}{}} \newlabel{eq:merge-local-I-27@cref}{{[equation][20][21]21.20}{[1][320][]320}{}{}{}} \newlabel{eq:merge-local-I-28}{{21.21}{321}{The \texorpdfstring {$39$}{39}-trace law at every sorting cut}{equation.1543}{}} \newlabel{eq:merge-local-I-28@cref}{{[equation][21][21]21.21}{[1][321][]321}{}{}{}} \newlabel{eq:merge-local-I-29}{{21.22}{321}{Physical completion}{equation.1545}{}} \newlabel{eq:merge-local-I-29@cref}{{[equation][22][21]21.22}{[1][321][]321}{}{}{}} \newlabel{eq:merge-local-I-30}{{21.23}{321}{Physical completion}{equation.1546}{}} \newlabel{eq:merge-local-I-30@cref}{{[equation][23][21]21.23}{[1][321][]321}{}{}{}} \newlabel{lem:imp:coherent39-law}{{21.17}{321}{Admissibility of the coherent root}{lemma.1548}{}} \newlabel{lem:imp:coherent39-law@cref}{{[lemma][17][21]21.17}{[1][321][]321}{}{}{}} \newlabel{imp:local:coherent-39}{{21.18}{322}{Thirty-nine coherent traces at every sorting cut: the leading coefficients}{proposition.1550}{}} \newlabel{imp:local:coherent-39@cref}{{[proposition][18][21]21.18}{[1][322][]322}{}{}{}} \newlabel{eq:merge-local-I-31}{{21.24}{322}{Thirty-nine coherent traces at every sorting cut: the leading coefficients}{equation.1551}{}} \newlabel{eq:merge-local-I-31@cref}{{[equation][24][21]21.24}{[1][322][]322}{}{}{}} \newlabel{eq:merge-local-I-32}{{21.25}{322}{Physical completion}{equation.1552}{}} \newlabel{eq:merge-local-I-32@cref}{{[equation][25][21]21.25}{[1][322][]322}{}{}{}} \newlabel{eq:merge-local-I-33}{{21.26}{323}{Physical completion}{equation.1553}{}} \newlabel{eq:merge-local-I-33@cref}{{[equation][26][21]21.26}{[1][323][]323}{}{}{}} \newlabel{imp:local:coherent-parameter}{{21.19}{323}{The common coherent parameter interval}{proposition.1556}{}} \newlabel{imp:local:coherent-parameter@cref}{{[proposition][19][21]21.19}{[1][323][]323}{}{}{}} \newlabel{imp:env:coherent-parameter}{{21.19}{323}{The common coherent parameter interval}{proposition.1556}{}} \newlabel{imp:env:coherent-parameter@cref}{{[proposition][19][21]21.19}{[1][323][]323}{}{}{}} \newlabel{eq:merge-local-I-43}{{21.27}{323}{The common coherent parameter interval}{equation.1557}{}} \newlabel{eq:merge-local-I-43@cref}{{[equation][27][21]21.27}{[1][323][]323}{}{}{}} \newlabel{eq:merge-local-I-44}{{21.28}{324}{One parameter \texorpdfstring {$\ulaw $}{u} for both cuts of the \texorpdfstring {$39$}{39}-trace law}{equation.1558}{}} \newlabel{eq:merge-local-I-44@cref}{{[equation][28][21]21.28}{[1][324][]324}{}{}{}} \newlabel{imp:local:finite-coherent-layer-section}{{21.11}{324}{An explicit layer price for the coherent law}{subsection.1559}{}} \newlabel{imp:local:finite-coherent-layer-section@cref}{{[subsection][11][21]21.11}{[1][324][]324}{}{}{}} \newlabel{eq:merge-local-I-34}{{21.29}{324}{An explicit layer price for the coherent law}{equation.1560}{}} \newlabel{eq:merge-local-I-34@cref}{{[equation][29][21]21.29}{[1][324][]324}{}{}{}} \newlabel{eq:merge-local-I-35}{{21.30}{324}{An explicit layer price for the coherent law}{equation.1561}{}} \newlabel{eq:merge-local-I-35@cref}{{[equation][30][21]21.30}{[1][324][]324}{}{}{}} \newlabel{eq:merge-local-I-36}{{21.31}{324}{An explicit layer price for the coherent law}{equation.1562}{}} \newlabel{eq:merge-local-I-36@cref}{{[equation][31][21]21.31}{[1][324][]324}{}{}{}} \newlabel{imp:local:finite-coherent-layer}{{21.20}{324}{Finite layer-cut bound for the coherent law in the fixed half chart}{proposition.1564}{}} \newlabel{imp:local:finite-coherent-layer@cref}{{[proposition][20][21]21.20}{[1][324][]324}{}{}{}} \newlabel{eq:merge-local-I-37}{{21.32}{325}{Finite layer-cut bound for the coherent law in the fixed half chart}{equation.1565}{}} \newlabel{eq:merge-local-I-37@cref}{{[equation][32][21]21.32}{[1][324][]325}{}{}{}} \newlabel{eq:merge-local-I-38}{{21.33}{325}{Finite layer-cut bound for the coherent law in the fixed half chart}{equation.1566}{}} \newlabel{eq:merge-local-I-38@cref}{{[equation][33][21]21.33}{[1][325][]325}{}{}{}} \newlabel{eq:merge-local-I-39}{{21.34}{325}{An explicit layer price for the coherent law}{equation.1567}{}} \newlabel{eq:merge-local-I-39@cref}{{[equation][34][21]21.34}{[1][325][]325}{}{}{}} \newlabel{eq:merge-local-I-40}{{21.35}{326}{An explicit layer price for the coherent law}{equation.1568}{}} \newlabel{eq:merge-local-I-40@cref}{{[equation][35][21]21.35}{[1][325][]326}{}{}{}} \newlabel{eq:merge-local-I-41}{{21.36}{326}{An explicit layer price for the coherent law}{equation.1569}{}} \newlabel{eq:merge-local-I-41@cref}{{[equation][36][21]21.36}{[1][326][]326}{}{}{}} \newlabel{eq:merge-local-I-42}{{21.37}{326}{An explicit layer price for the coherent law}{equation.1570}{}} \newlabel{eq:merge-local-I-42@cref}{{[equation][37][21]21.37}{[1][326][]326}{}{}{}} \newlabel{imp:env:finite-coherent-section}{{21.12}{327}{A finite chamber price for the coherent law}{subsection.1571}{}} \newlabel{imp:env:finite-coherent-section@cref}{{[subsection][12][21]21.12}{[1][327][]327}{}{}{}} \newlabel{imp:env:coherent-score-bound}{{21.38}{327}{A finite chamber price for the coherent law}{equation.1572}{}} \newlabel{imp:env:coherent-score-bound@cref}{{[equation][38][21]21.38}{[1][327][]327}{}{}{}} \newlabel{imp:env:coherent-full-covariance}{{21.21}{327}{Full coherent covariance}{lemma.1574}{}} \newlabel{imp:env:coherent-full-covariance@cref}{{[lemma][21][21]21.21}{[1][327][]327}{}{}{}} \newlabel{imp:env:coherent-E2}{{21.39}{327}{Full coherent covariance}{equation.1575}{}} \newlabel{imp:env:coherent-E2@cref}{{[equation][39][21]21.39}{[1][327][]327}{}{}{}} \newlabel{imp:env:coherent-linear-finite}{{21.22}{328}{Finite coherent linear error}{lemma.1577}{}} \newlabel{imp:env:coherent-linear-finite@cref}{{[lemma][22][21]21.22}{[1][328][]328}{}{}{}} \newlabel{imp:env:coherent-normalization}{{21.40}{329}{A finite chamber price for the coherent law}{equation.1578}{}} \newlabel{imp:env:coherent-normalization@cref}{{[equation][40][21]21.40}{[1][329][]329}{}{}{}} \newlabel{imp:env:coherent-final-prices}{{21.41}{329}{A finite chamber price for the coherent law}{equation.1579}{}} \newlabel{imp:env:coherent-final-prices@cref}{{[equation][41][21]21.41}{[1][329][]329}{}{}{}} \newlabel{imp:env:finite-coherent-chamber}{{21.23}{329}{Finite chamber-cut bound and marginal data for the coherent law}{proposition.1581}{}} \newlabel{imp:env:finite-coherent-chamber@cref}{{[proposition][23][21]21.23}{[1][329][]329}{}{}{}} \newlabel{imp:env:coherent-single-pin}{{21.24}{330}{The coherent score on a single collision}{proposition.1583}{}} \newlabel{imp:env:coherent-single-pin@cref}{{[proposition][24][21]21.24}{[1][330][]330}{}{}{}} \newlabel{subsec:positive-root-caps}{{21.13}{331}{Values of the bounds at the seven interval starts}{subsection.1584}{}} \newlabel{subsec:positive-root-caps@cref}{{[subsection][13][21]21.13}{[1][331][]331}{}{}{}} \newlabel{cert:positive-root-caps}{{21.25}{331}{The positive roots}{certificate.1586}{}} \newlabel{cert:positive-root-caps@cref}{{[certificate][25][21]21.25}{[1][331][]331}{}{}{}} \newlabel{rem:positive-root-family}{{21.26}{332}{The family of tilts}{remark.1588}{}} \newlabel{rem:positive-root-family@cref}{{[remark][26][21]21.26}{[1][332][]332}{}{}{}} \newlabel{sec:middle-frame}{{22}{333}{Middle primes III: the reference law \texorpdfstring {$\mu $}{mu}, first stage \texorpdfstring {$\lambda $}{lambda}, and its dominator}{section.1591}{}} \newlabel{sec:middle-frame@cref}{{[section][22][]22}{[1][333][]333}{}{}{}} \newlabel{subsec:middle-reference-law}{{22.1}{334}{The reference law of a middle block}{subsection.1593}{}} \newlabel{subsec:middle-reference-law@cref}{{[subsection][1][22]22.1}{[1][334][]334}{}{}{}} \newlabel{lem:front12:reference}{{22.1}{334}{The reference}{lemma.1596}{}} \newlabel{lem:front12:reference@cref}{{[lemma][1][22]22.1}{[1][334][]334}{}{}{}} \newlabel{eq:protection}{{22.1}{335}{The reference}{equation.1601}{}} \newlabel{eq:protection@cref}{{[equation][1][22]22.1}{[1][335][]335}{}{}{}} \newlabel{rem:middle-weights}{{22.2}{337}{The certified weights}{remark.1603}{}} \newlabel{rem:middle-weights@cref}{{[remark][2][22]22.2}{[1][337][]337}{}{}{}} \newlabel{rem:root-charts}{{22.3}{337}{The fixed half charts}{remark.1605}{}} \newlabel{rem:root-charts@cref}{{[remark][3][22]22.3}{[1][337][]337}{}{}{}} \newlabel{subsec:middle-first-stage}{{22.2}{337}{The first stage \texorpdfstring {$\lambda $}{lambda} (polarization and one-stage replacements)}{subsection.1606}{}} \newlabel{subsec:middle-first-stage@cref}{{[subsection][2][22]22.2}{[1][337][]337}{}{}{}} \newlabel{def:record:frame}{{22.4}{338}{The middle frame}{definition.1608}{}} \newlabel{def:record:frame@cref}{{[definition][4][22]22.4}{[1][338][]338}{}{}{}} \newlabel{lem:middle-polarization}{{22.5}{339}{The polarized first stage}{lemma.1615}{}} \newlabel{lem:middle-polarization@cref}{{[lemma][5][22]22.5}{[1][339][]339}{}{}{}} \newlabel{lem:record:one-stage-folded-e}{{22.6}{339}{One-stage replacement of the folded matching records}{lemma.1618}{}} \newlabel{lem:record:one-stage-folded-e@cref}{{[lemma][6][22]22.6}{[1][339][]339}{}{}{}} \newlabel{subsec:middle-gram}{{22.3}{342}{The law \texorpdfstring {$\Nbr $}{N} dominating \texorpdfstring {$\lambda $}{lambda} at \texorpdfstring {$\iota $}{iota}}{subsection.1624}{}} \newlabel{subsec:middle-gram@cref}{{[subsection][3][22]22.3}{[1][342][]342}{}{}{}} \newlabel{lem:record:gram}{{22.7}{342}{The $2\times 2$ block dominating $\lambda $ at $\iota $}{lemma.1626}{}} \newlabel{lem:record:gram@cref}{{[lemma][7][22]22.7}{[1][342][]342}{}{}{}} \newlabel{rem:middle-bracket}{{22.8}{342}{What the bracket buys}{remark.1630}{}} \newlabel{rem:middle-bracket@cref}{{[remark][8][22]22.8}{[1][342][]342}{}{}{}} \newlabel{subsec:middle-frame-prices}{{22.4}{343}{Prices \texorpdfstring {$L_0$}{L\_0} and \texorpdfstring {$B$}{B} for \texorpdfstring {$\lambda $}{lambda} and \texorpdfstring {$\Nbr $}{N}}{subsection.1631}{}} \newlabel{subsec:middle-frame-prices@cref}{{[subsection][4][22]22.4}{[1][343][]343}{}{}{}} \newlabel{lem:record:middle-prices}{{22.9}{343}{Middle prices}{lemma.1633}{}} \newlabel{lem:record:middle-prices@cref}{{[lemma][9][22]22.9}{[1][343][]343}{}{}{}} \newlabel{sec:middle-records}{{23}{344}{Middle primes IV: the comparison law \texorpdfstring {$\nu $}{nu} and its prices \texorpdfstring {$S,A$}{S,A}}{section.1636}{}} \newlabel{sec:middle-records@cref}{{[section][23][]23}{[1][344][]344}{}{}{}} \newlabel{subsec:middle-records:notation}{{23.1}{345}{One prime: halves, kernels and channels}{subsection.1638}{}} \newlabel{subsec:middle-records:notation@cref}{{[subsection][1][23]23.1}{[1][345][]345}{}{}{}} \newlabel{eq:middle:channels}{{23.1}{346}{The Paley channels}{equation.1641}{}} \newlabel{eq:middle:channels@cref}{{[equation][1][23]23.1}{[1][345][]346}{}{}{}} \newlabel{eq:middle:transpose}{{23.2}{346}{The Paley channels}{equation.1642}{}} \newlabel{eq:middle:transpose@cref}{{[equation][2][23]23.2}{[1][346][]346}{}{}{}} \newlabel{lem:two-feature-spectrum}{{23.1}{346}{Two-feature spectral calculation}{lemma.1645}{}} \newlabel{lem:two-feature-spectrum@cref}{{[lemma][1][23]23.1}{[1][346][]346}{}{}{}} \newlabel{subsec:old-f}{{23.2}{347}{The reference fold record at the reserved cut}{subsection.1647}{}} \newlabel{subsec:old-f@cref}{{[subsection][2][23]23.2}{[1][347][]347}{}{}{}} \newlabel{lem:old-f-law}{{23.2}{347}{The reference fold record}{lemma.1649}{}} \newlabel{lem:old-f-law@cref}{{[lemma][2][23]23.2}{[1][347][]347}{}{}{}} \newlabel{lem:record:old-f-marginal}{{23.3}{349}{Actual marginal and centred norm of the reference fold record}{corollary.1660}{}} \newlabel{lem:record:old-f-marginal@cref}{{[corollary][3][23]23.3}{[1][349][]349}{}{}{}} \newlabel{lem:actual-features}{{23.4}{350}{Exact actual features}{lemma.1666}{}} \newlabel{lem:actual-features@cref}{{[lemma][4][23]23.4}{[1][350][]350}{}{}{}} \newlabel{subsec:mirror}{{23.3}{351}{Adding an edge together with its mirror: first-order change purely skew}{subsection.1672}{}} \newlabel{subsec:mirror@cref}{{[subsection][3][23]23.3}{[1][351][]351}{}{}{}} \newlabel{lem:mirror}{{23.5}{352}{Mirror pairing}{lemma.1674}{}} \newlabel{lem:mirror@cref}{{[lemma][5][23]23.5}{[1][352][]352}{}{}{}} \newlabel{rem:mirror-why}{{23.6}{353}{Why the mirror}{remark.1680}{}} \newlabel{rem:mirror-why@cref}{{[remark][6][23]23.6}{[1][353][]353}{}{}{}} \newlabel{subsec:oct24:pure-local}{{23.4}{353}{The signed combination over a whole block replacing \texorpdfstring {$F_1,F_2$}{F\_1,F\_2}}{subsection.1681}{}} \newlabel{subsec:oct24:pure-local@cref}{{[subsection][4][23]23.4}{[1][353][]353}{}{}{}} \newlabel{lem:signed-components}{{23.7}{353}{Positive components with the actual half marginal}{lemma.1683}{}} \newlabel{lem:signed-components@cref}{{[lemma][7][23]23.7}{[1][353][]353}{}{}{}} \newlabel{def:record:mixture}{{23.9}{355}{The signed whole-block fold record}{definition.1691}{}} \newlabel{def:record:mixture@cref}{{[definition][9][23]23.9}{[1][355][]355}{}{}{}} \newlabel{eq:signed-law}{{23.3}{355}{The signed whole-block fold record}{equation.1695}{}} \newlabel{eq:signed-law@cref}{{[equation][3][23]23.3}{[1][355][]355}{}{}{}} \newlabel{eq:signed-leading}{{23.4}{355}{The signed combination over a whole block replacing \texorpdfstring {$F_1,F_2$}{F\_1,F\_2}}{equation.1698}{}} \newlabel{eq:signed-leading@cref}{{[equation][4][23]23.4}{[1][355][]355}{}{}{}} \newlabel{cert:record:middle-geometry}{{23.10}{355}{Query images of the middle records}{certificate.1701}{}} \newlabel{cert:record:middle-geometry@cref}{{[certificate][10][23]23.10}{[1][355][]355}{}{}{}} \newlabel{subsec:record:f_remainders}{{23.5}{356}{Nonstar and coincidence remainders}{subsection.1702}{}} \newlabel{subsec:record:f_remainders@cref}{{[subsection][5][23]23.5}{[1][356][]356}{}{}{}} \newlabel{lem:record:projected-nonstar}{{23.11}{356}{Projected nonstars and rectangular stars}{lemma.1704}{}} \newlabel{lem:record:projected-nonstar@cref}{{[lemma][11][23]23.11}{[1][356][]356}{}{}{}} \newlabel{lem:record:conditional-collision}{{23.12}{356}{Conditional collisions}{lemma.1708}{}} \newlabel{lem:record:conditional-collision@cref}{{[lemma][12][23]23.12}{[1][356][]356}{}{}{}} \newlabel{subsec:pure-bounds}{{23.6}{359}{Prime and block bounds of the signed fold records}{subsection.1713}{}} \newlabel{subsec:pure-bounds@cref}{{[subsection][6][23]23.6}{[1][359][]359}{}{}{}} \newlabel{eq:signed-constants}{{23.5}{360}{Prime and block bounds of the signed fold records}{equation.1714}{}} \newlabel{eq:signed-constants@cref}{{[equation][5][23]23.5}{[1][359][]360}{}{}{}} \newlabel{prop:signed-bounds}{{23.13}{360}{Prime and block bounds of the signed fold records}{proposition.1716}{}} \newlabel{prop:signed-bounds@cref}{{[proposition][13][23]23.13}{[1][360][]360}{}{}{}} \newlabel{cert:signed-local}{{23.14}{362}{The constants of the signed law and of the matching records}{certificate.1723}{}} \newlabel{cert:signed-local@cref}{{[certificate][14][23]23.14}{[1][362][]362}{}{}{}} \newlabel{subsec:record:e_side}{{23.7}{363}{The matching records \texorpdfstring {$E_0,E_1$}{E\_0,E\_1} and their replacement \texorpdfstring {$K_1$}{K\_1}}{subsection.1724}{}} \newlabel{subsec:record:e_side@cref}{{[subsection][7][23]23.7}{[1][363][]363}{}{}{}} \newlabel{lem:record:e-law}{{23.15}{363}{The exact-marginal matching law}{lemma.1727}{}} \newlabel{lem:record:e-law@cref}{{[lemma][15][23]23.15}{[1][363][]363}{}{}{}} \newlabel{lem:record:e-orthogonal}{{23.16}{365}{Orthogonal channels}{lemma.1733}{}} \newlabel{lem:record:e-orthogonal@cref}{{[lemma][16][23]23.16}{[1][365][]365}{}{}{}} \newlabel{lem:record:exact-marginal-e}{{23.17}{365}{Prices of the matching records}{lemma.1738}{}} \newlabel{lem:record:exact-marginal-e@cref}{{[lemma][17][23]23.17}{[1][365][]365}{}{}{}} \newlabel{lem:oct24:matching-star}{{23.18}{366}{Matching one-arm stars}{lemma.1742}{}} \newlabel{lem:oct24:matching-star@cref}{{[lemma][18][23]23.18}{[1][366][]366}{}{}{}} \newlabel{subsec:merge-repair}{{23.8}{367}{Merges replaced at fixed marginals, and deleted records}{subsection.1743}{}} \newlabel{subsec:merge-repair@cref}{{[subsection][8][23]23.8}{[1][367][]367}{}{}{}} \newlabel{def:merge-records}{{23.19}{367}{Merge records and their designated edges}{definition.1745}{}} \newlabel{def:merge-records@cref}{{[definition][19][23]23.19}{[1][367][]367}{}{}{}} \newlabel{tab:merge-records}{{11}{367}{The six merge records and their accepting replacements. Each replacement has exactly the original ordered-distinct-pair half laws}{table.1746}{}} \newlabel{tab:merge-records@cref}{{[table][11][]11}{[1][367][]367}{}{}{}} \newlabel{lem:merge-repair}{{23.20}{367}{Exact merge repairs}{lemma.1748}{}} \newlabel{lem:merge-repair@cref}{{[lemma][20][23]23.20}{[1][367][]367}{}{}{}} \newlabel{eq:merge:mirror-identities}{{23.6}{368}{Merges replaced at fixed marginals, and deleted records}{equation.1749}{}} \newlabel{eq:merge:mirror-identities@cref}{{[equation][6][23]23.6}{[1][368][]368}{}{}{}} \newlabel{cor:merge-repair}{{23.21}{369}{The six merge prices}{corollary.1751}{}} \newlabel{cor:merge-repair@cref}{{[corollary][21][23]23.21}{[1][369][]369}{}{}{}} \newlabel{cert:merge-coefficients}{{23.22}{369}{The merge coefficients}{certificate.1753}{}} \newlabel{cert:merge-coefficients@cref}{{[certificate][22][23]23.22}{[1][369][]369}{}{}{}} \newlabel{lem:record:accepting-c2}{{23.23}{369}{Accepting two-layer constants}{lemma.1755}{}} \newlabel{lem:record:accepting-c2@cref}{{[lemma][23][23]23.23}{[1][369][]369}{}{}{}} \newlabel{subsec:middle-comparison}{{23.9}{370}{The comparison law of a middle block and its prices}{subsection.1757}{}} \newlabel{subsec:middle-comparison@cref}{{[subsection][9][23]23.9}{[1][370][]370}{}{}{}} \newlabel{lem:middle-comparison-prices}{{23.24}{371}{Comparison prices of a middle block}{lemma.1759}{}} \newlabel{lem:middle-comparison-prices@cref}{{[lemma][24][23]23.24}{[1][371][]371}{}{}{}} \newlabel{eq:middle-piece-prices}{{23.7}{372}{The comparison law of a middle block and its prices}{equation.1760}{}} \newlabel{eq:middle-piece-prices@cref}{{[equation][7][23]23.7}{[1][372][]372}{}{}{}} \newlabel{sec:variance}{{24}{373}{The variance identity: savings \texorpdfstring {$D_{\mathrm {var}}$}{D\_var} from fixed marginals}{section.1763}{}} \newlabel{sec:variance@cref}{{[section][24][]24}{[1][373][]373}{}{}{}} \newlabel{subsec:variance:eligible}{{24.1}{374}{The four records treated here}{subsection.1765}{}} \newlabel{subsec:variance:eligible@cref}{{[subsection][1][24]24.1}{[1][374][]374}{}{}{}} \newlabel{def:record:eligible}{{24.1}{374}{Eligible records and repairs}{definition.1767}{}} \newlabel{def:record:eligible@cref}{{[definition][1][24]24.1}{[1][374][]374}{}{}{}} \newlabel{eq:record:zero-marginal}{{24.1}{375}{The four records treated here}{equation.1768}{}} \newlabel{eq:record:zero-marginal@cref}{{[equation][1][24]24.1}{[1][375][]375}{}{}{}} \newlabel{hyp:variance:A}{{24.2}{375}{Root density, (A)}{hypothesis.1770}{}} \newlabel{hyp:variance:A@cref}{{[hypothesis][2][24]24.2}{[1][375][]375}{}{}{}} \newlabel{subsec:variance:root}{{24.2}{375}{Comparing the principal half law with the record half law}{subsection.1771}{}} \newlabel{subsec:variance:root@cref}{{[subsection][2][24]24.2}{[1][375][]375}{}{}{}} \newlabel{lem:record:weighted-moment}{{24.3}{376}{Second moment of the neighbourhood count}{lemma.1774}{}} \newlabel{lem:record:weighted-moment@cref}{{[lemma][3][24]24.3}{[1][376][]376}{}{}{}} \newlabel{eq:record:weighted-identity}{{24.2}{376}{Second moment of the neighbourhood count}{equation.1776}{}} \newlabel{eq:record:weighted-identity@cref}{{[equation][2][24]24.2}{[1][376][]376}{}{}{}} \newlabel{eq:record:modular-moment}{{24.3}{376}{Second moment of the neighbourhood count}{equation.1778}{}} \newlabel{eq:record:modular-moment@cref}{{[equation][3][24]24.3}{[1][376][]376}{}{}{}} \newlabel{rem:variance:crude}{{24.4}{378}{The crude second moment}{remark.1780}{}} \newlabel{rem:variance:crude@cref}{{[remark][4][24]24.4}{[1][378][]378}{}{}{}} \newlabel{lem:l20-star-mean}{{24.5}{378}{The first moment of the four-root count}{lemma.1783}{}} \newlabel{lem:l20-star-mean@cref}{{[lemma][5][24]24.5}{[1][378][]378}{}{}{}} \newlabel{eq:l20-star-identities}{{24.4}{378}{The first moment of the four-root count}{equation.1784}{}} \newlabel{eq:l20-star-identities@cref}{{[equation][4][24]24.4}{[1][378][]378}{}{}{}} \newlabel{eq:partition-coefficient}{{24.5}{378}{The first moment of the four-root count}{equation.1785}{}} \newlabel{eq:partition-coefficient@cref}{{[equation][5][24]24.5}{[1][378][]378}{}{}{}} \newlabel{cert:l20-star-mean}{{24.6}{379}{The four-root first moment}{certificate.1787}{}} \newlabel{cert:l20-star-mean@cref}{{[certificate][6][24]24.6}{[1][379][]379}{}{}{}} \newlabel{lem:record:root-marginal}{{24.7}{379}{Root completion count}{lemma.1789}{}} \newlabel{lem:record:root-marginal@cref}{{[lemma][7][24]24.7}{[1][379][]379}{}{}{}} \newlabel{eq:record:root-count}{{24.6}{380}{The first moment of the four-root count}{equation.1794}{}} \newlabel{eq:record:root-count@cref}{{[equation][6][24]24.6}{[1][380][]380}{}{}{}} \newlabel{subsec:variance:restoration}{{24.3}{381}{Recovering product energy on a common chamber}{subsection.1795}{}} \newlabel{subsec:variance:restoration@cref}{{[subsection][3][24]24.3}{[1][381][]381}{}{}{}} \newlabel{lem:record:restoration}{{24.8}{382}{Restoration on a common chamber}{lemma.1797}{}} \newlabel{lem:record:restoration@cref}{{[lemma][8][24]24.8}{[1][382][]382}{}{}{}} \newlabel{eq:record:nonroot-mass}{{24.7}{382}{Restoration on a common chamber}{equation.1798}{}} \newlabel{eq:record:nonroot-mass@cref}{{[equation][7][24]24.7}{[1][382][]382}{}{}{}} \newlabel{rem:variance:branches}{{24.9}{383}{The three branches}{remark.1800}{}} \newlabel{rem:variance:branches@cref}{{[remark][9][24]24.9}{[1][383][]383}{}{}{}} \newlabel{subsec:variance:centred}{{24.4}{383}{Centred norms at the reserved cut}{subsection.1801}{}} \newlabel{subsec:variance:centred@cref}{{[subsection][4][24]24.4}{[1][383][]383}{}{}{}} \newlabel{subsec:variance:matching}{{24.5}{383}{Variance savings for \texorpdfstring {$E_0,E_1$}{E\_0,E\_1} via polarization}{subsection.1802}{}} \newlabel{subsec:variance:matching@cref}{{[subsection][5][24]24.5}{[1][383][]383}{}{}{}} \newlabel{lem:record:paired-e-bridge}{{24.10}{383}{Paired $E$ bridge}{lemma.1804}{}} \newlabel{lem:record:paired-e-bridge@cref}{{[lemma][10][24]24.10}{[1][383][]383}{}{}{}} \newlabel{lem:record:paired-e-joint}{{24.11}{384}{Matching selections}{lemma.1808}{}} \newlabel{lem:record:paired-e-joint@cref}{{[lemma][11][24]24.11}{[1][384][]384}{}{}{}} \newlabel{subsec:variance:gain}{{24.6}{385}{The saving \texorpdfstring {$g$}{g}: product energy at least \texorpdfstring {$gC_XY$}{gC\_XY}}{subsection.1812}{}} \newlabel{subsec:variance:gain@cref}{{[subsection][6][24]24.6}{[1][385][]385}{}{}{}} \newlabel{lem:var-gain}{{24.12}{385}{Variance gain}{lemma.1814}{}} \newlabel{lem:var-gain@cref}{{[lemma][12][24]24.12}{[1][385][]385}{}{}{}} \newlabel{cor:var-classes}{{24.13}{386}{The eligible variance classes}{corollary.1819}{}} \newlabel{cor:var-classes@cref}{{[corollary][13][24]24.13}{[1][386][]386}{}{}{}} \newlabel{rem:variance:independence}{{24.14}{386}{Repair independence}{remark.1824}{}} \newlabel{rem:variance:independence@cref}{{[remark][14][24]24.14}{[1][386][]386}{}{}{}} \newlabel{subsec:variance:backgrounds}{{24.7}{386}{Additional positive terms in the exterior energy}{subsection.1825}{}} \newlabel{subsec:variance:backgrounds@cref}{{[subsection][7][24]24.7}{[1][386][]386}{}{}{}} \newlabel{eq:variance:margins}{{24.8}{387}{Piece data}{equation.1827}{}} \newlabel{eq:variance:margins@cref}{{[equation][8][24]24.8}{[1][387][]387}{}{}{}} \newlabel{lem:distinct-choice}{{24.15}{387}{Distinct choices}{lemma.1829}{}} \newlabel{lem:distinct-choice@cref}{{[lemma][15][24]24.15}{[1][387][]387}{}{}{}} \newlabel{eq:variance:choice-weight}{{24.9}{387}{Distinct choices}{equation.1831}{}} \newlabel{eq:variance:choice-weight@cref}{{[equation][9][24]24.9}{[1][387][]387}{}{}{}} \newlabel{lem:pool-coupons}{{24.16}{388}{Terms pooled over the pieces from $2^{31}$}{lemma.1835}{}} \newlabel{lem:pool-coupons@cref}{{[lemma][16][24]24.16}{[1][388][]388}{}{}{}} \newlabel{prop:background-variance}{{24.17}{389}{Positive backgrounds in a selected variance}{proposition.1839}{}} \newlabel{prop:background-variance@cref}{{[proposition][17][24]24.17}{[1][389][]389}{}{}{}} \newlabel{eq:variance:background-gain}{{24.10}{389}{Positive backgrounds in a selected variance}{equation.1840}{}} \newlabel{eq:variance:background-gain@cref}{{[equation][10][24]24.10}{[1][389][]389}{}{}{}} \newlabel{subsec:variance:final}{{24.8}{390}{Assembly: the total saving \texorpdfstring {$D_{\rm var}$}{D\_var}}{subsection.1843}{}} \newlabel{subsec:variance:final@cref}{{[subsection][8][24]24.8}{[1][390][]390}{}{}{}} \newlabel{eq:variance:pieces}{{24.11}{391}{Piece values}{equation.1845}{}} \newlabel{eq:variance:pieces@cref}{{[equation][11][24]24.11}{[1][391][]391}{}{}{}} \newlabel{eq:variance:fresh}{{24.12}{391}{Fresh restorations and gains}{equation.1848}{}} \newlabel{eq:variance:fresh@cref}{{[equation][12][24]24.12}{[1][391][]391}{}{}{}} \newlabel{eq:variance:dvar}{{24.13}{392}{The credit}{equation.1851}{}} \newlabel{eq:variance:dvar@cref}{{[equation][13][24]24.13}{[1][391][]392}{}{}{}} \newlabel{cor:variance:final}{{24.18}{392}{The variance credits of the final construction}{corollary.1853}{}} \newlabel{cor:variance:final@cref}{{[corollary][18][24]24.18}{[1][392][]392}{}{}{}} \newlabel{cert:variance:fresh}{{24.19}{393}{Restorations recomputed at the baseline exponent}{certificate.1859}{}} \newlabel{cert:variance:fresh@cref}{{[certificate][19][24]24.19}{[1][393][]393}{}{}{}} \newlabel{rem:variance:sizes}{{24.20}{394}{Sizes}{remark.1861}{}} \newlabel{rem:variance:sizes@cref}{{[remark][20][24]24.20}{[1][394][]394}{}{}{}} \newlabel{rem:variance:robust}{{24.21}{394}{Robustness}{remark.1863}{}} \newlabel{rem:variance:robust@cref}{{[remark][21][24]24.21}{[1][394][]394}{}{}{}} \newlabel{sec:envelopes}{{25}{395}{Products of skew changes: dominating matrices and savings}{section.1866}{}} \newlabel{sec:envelopes@cref}{{[section][25][]25}{[1][395][]395}{}{}{}} \newlabel{subsec:oct24:pure-features}{{25.1}{396}{Star features in the true half laws}{subsection.1869}{}} \newlabel{subsec:oct24:pure-features@cref}{{[subsection][1][25]25.1}{[1][396][]396}{}{}{}} \newlabel{lem:oct24:feature-block}{{25.1}{397}{The actual feature frame}{lemma.1872}{}} \newlabel{lem:oct24:feature-block@cref}{{[lemma][1][25]25.1}{[1][397][]397}{}{}{}} \newlabel{eq:feature-perron}{{25.1}{397}{The actual feature frame}{equation.1875}{}} \newlabel{eq:feature-perron@cref}{{[equation][1][25]25.1}{[1][397][]397}{}{}{}} \newlabel{eq:oct24:feature-constants}{{25.2}{397}{The actual feature frame}{equation.1877}{}} \newlabel{eq:oct24:feature-constants@cref}{{[equation][2][25]25.2}{[1][397][]397}{}{}{}} \newlabel{subsec:envelope-tools}{{25.2}{399}{Dominating matrices for tensors of star operators}{subsection.1878}{}} \newlabel{subsec:envelope-tools@cref}{{[subsection][2][25]25.2}{[1][399][]399}{}{}{}} \newlabel{lem:oct24:pure-pair-substitute}{{25.2}{400}{A positive substitute for a pure-pair projection}{lemma.1880}{}} \newlabel{lem:oct24:pure-pair-substitute@cref}{{[lemma][2][25]25.2}{[1][399][]400}{}{}{}} \newlabel{eq:oct24:pure-pair-substitute}{{25.3}{400}{A positive substitute for a pure-pair projection}{equation.1881}{}} \newlabel{eq:oct24:pure-pair-substitute@cref}{{[equation][3][25]25.3}{[1][400][]400}{}{}{}} \newlabel{eq:signed-star}{{25.4}{400}{Signed stars}{equation.1883}{}} \newlabel{eq:signed-star@cref}{{[equation][4][25]25.4}{[1][400][]400}{}{}{}} \newlabel{it:env:N1}{{{{(N1)}}}{401}{Signed stars}{Item.1884}{}} \newlabel{it:env:N1@cref}{{[enumi][1][]{{(N1)}}}{[1][401][]401}{}{}{}} \newlabel{it:env:N2}{{{{(N2)}}}{401}{Signed stars}{Item.1885}{}} \newlabel{it:env:N2@cref}{{[enumi][2][]{{(N2)}}}{[1][401][]401}{}{}{}} \newlabel{it:env:N3}{{{{(N3)}}}{401}{Signed stars}{Item.1886}{}} \newlabel{it:env:N3@cref}{{[enumi][3][]{{(N3)}}}{[1][401][]401}{}{}{}} \newlabel{it:env:N4}{{{{(N4)}}}{401}{Signed stars}{Item.1887}{}} \newlabel{it:env:N4@cref}{{[enumi][4][]{{(N4)}}}{[1][401][]401}{}{}{}} \newlabel{eq:oct24:star-tensor-error}{{25.5}{402}{Signed stars}{equation.1888}{}} \newlabel{eq:oct24:star-tensor-error@cref}{{[equation][5][25]25.5}{[1][402][]402}{}{}{}} \newlabel{lem:oct24:mask-schur}{{25.3}{402}{Matrix envelopes}{lemma.1890}{}} \newlabel{lem:oct24:mask-schur@cref}{{[lemma][3][25]25.3}{[1][402][]402}{}{}{}} \newlabel{eq:matrix-envelope}{{25.6}{402}{Matrix envelopes}{equation.1891}{}} \newlabel{eq:matrix-envelope@cref}{{[equation][6][25]25.6}{[1][402][]402}{}{}{}} \newlabel{eq:oct24:mask-schur}{{25.7}{403}{Matrix envelopes}{equation.1895}{}} \newlabel{eq:oct24:mask-schur@cref}{{[equation][7][25]25.7}{[1][402][]403}{}{}{}} \newlabel{rem:envelope-gain}{{25.4}{404}{Where the gain comes from}{remark.1898}{}} \newlabel{rem:envelope-gain@cref}{{[remark][4][25]25.4}{[1][404][]404}{}{}{}} \newlabel{subsec:reflection-averaging}{{25.3}{405}{Averaging a dominating matrix over reflections}{subsection.1899}{}} \newlabel{subsec:reflection-averaging@cref}{{[subsection][3][25]25.3}{[1][405][]405}{}{}{}} \newlabel{lem:reflection-averaging}{{25.5}{405}{Reflection averaging}{lemma.1902}{}} \newlabel{lem:reflection-averaging@cref}{{[lemma][5][25]25.5}{[1][405][]405}{}{}{}} \newlabel{subsec:oct24:pure-background}{{25.4}{408}{Outside laws invariant under reflections, and their price}{subsection.1910}{}} \newlabel{subsec:oct24:pure-background@cref}{{[subsection][4][25]25.4}{[1][408][]408}{}{}{}} \newlabel{lem:oct24:invariant-background}{{25.6}{408}{Invariant outside laws}{lemma.1912}{}} \newlabel{lem:oct24:invariant-background@cref}{{[lemma][6][25]25.6}{[1][408][]408}{}{}{}} \newlabel{eq:invariant-price}{{25.8}{408}{Invariant outside laws}{equation.1918}{}} \newlabel{eq:invariant-price@cref}{{[equation][8][25]25.8}{[1][408][]408}{}{}{}} \newlabel{lem:orbit-coupon}{{25.7}{410}{Invariant coupling orbits for exactly one folded error}{lemma.1920}{}} \newlabel{lem:orbit-coupon@cref}{{[lemma][7][25]25.7}{[1][410][]410}{}{}{}} \newlabel{subsec:envelope-theorem}{{25.5}{411}{(CP5) bounds for products of skew changes}{subsection.1925}{}} \newlabel{subsec:envelope-theorem@cref}{{[subsection][5][25]25.5}{[1][411][]411}{}{}{}} \newlabel{thm:envelopes}{{25.8}{412}{Positive joint envelopes}{theorem.1928}{}} \newlabel{thm:envelopes@cref}{{[theorem][8][25]25.8}{[1][412][]412}{}{}{}} \newlabel{eq:envelope-class-bound}{{25.9}{412}{Positive joint envelopes}{equation.1930}{}} \newlabel{eq:envelope-class-bound@cref}{{[equation][9][25]25.9}{[1][412][]412}{}{}{}} \newlabel{eq:oct24:envelope-cost}{{25.10}{412}{Positive joint envelopes}{equation.1932}{}} \newlabel{eq:oct24:envelope-cost@cref}{{[equation][10][25]25.10}{[1][412][]412}{}{}{}} \newlabel{eq:envelope-background}{{25.11}{412}{Positive joint envelopes}{equation.1934}{}} \newlabel{eq:envelope-background@cref}{{[equation][11][25]25.11}{[1][412][]412}{}{}{}} \newlabel{subsec:class-credit}{{25.6}{414}{Variance savings retained inside dominating matrices}{subsection.1941}{}} \newlabel{subsec:class-credit@cref}{{[subsection][6][25]25.6}{[1][414][]414}{}{}{}} \newlabel{lem:class-credit}{{25.9}{414}{Variance credit inside a positive envelope}{lemma.1943}{}} \newlabel{lem:class-credit@cref}{{[lemma][9][25]25.9}{[1][414][]414}{}{}{}} \newlabel{subsec:envelope-costs}{{25.7}{416}{Sixteen classes and their savings}{subsection.1948}{}} \newlabel{subsec:envelope-costs@cref}{{[subsection][7][25]25.7}{[1][416][]416}{}{}{}} \newlabel{cor:envelope-costs}{{25.10}{416}{The class bounds of the construction}{corollary.1950}{}} \newlabel{cor:envelope-costs@cref}{{[corollary][10][25]25.10}{[1][416][]416}{}{}{}} \newlabel{cert:envelopes}{{25.11}{417}{The sixteen dominating matrices and their class bounds}{certificate.1957}{}} \newlabel{cert:envelopes@cref}{{[certificate][11][25]25.11}{[1][417][]417}{}{}{}} \newlabel{sec:matching-mean}{{26}{419}{Dominators for \texorpdfstring {$\nu $}{nu} and the mean constant \texorpdfstring {$m>1$}{m>1}}{section.1964}{}} \newlabel{sec:matching-mean@cref}{{[section][26][]26}{[1][419][]419}{}{}{}} \newlabel{subsec:record:direct_gram}{{26.1}{420}{A joint \texorpdfstring {$2\times 2$}{2 x 2} block for reference and comparison records}{subsection.1966}{}} \newlabel{subsec:record:direct_gram@cref}{{[subsection][1][26]26.1}{[1][419][]420}{}{}{}} \newlabel{lem:record:direct-gram}{{26.1}{420}{The leading Gram}{lemma.1968}{}} \newlabel{lem:record:direct-gram@cref}{{[lemma][1][26]26.1}{[1][420][]420}{}{}{}} \newlabel{def:side-function}{{26.2}{421}{The side function}{definition.1971}{}} \newlabel{def:side-function@cref}{{[definition][2][26]26.2}{[1][421][]421}{}{}{}} \newlabel{lem:record:asymmetric-gram}{{26.3}{422}{Unequal sides}{lemma.1973}{}} \newlabel{lem:record:asymmetric-gram@cref}{{[lemma][3][26]26.3}{[1][422][]422}{}{}{}} \newlabel{subsec:signed-sides}{{26.2}{424}{The sides of the signed law}{subsection.1978}{}} \newlabel{subsec:signed-sides@cref}{{[subsection][2][26]26.2}{[1][424][]424}{}{}{}} \newlabel{prop:signed-sides}{{26.4}{424}{The sides of the signed law}{proposition.1980}{}} \newlabel{prop:signed-sides@cref}{{[proposition][4][26]26.4}{[1][424][]424}{}{}{}} \newlabel{eq:signed-increment}{{26.1}{424}{The sides of the signed law}{equation.1983}{}} \newlabel{eq:signed-increment@cref}{{[equation][1][26]26.1}{[1][424][]424}{}{}{}} \newlabel{subsec:matching-envelopes}{{26.3}{425}{The dominators \texorpdfstring {$M_{\rm L},M_{\rm R}$}{M\_L,M\_R} and the total \texorpdfstring {$T$}{T}}{subsection.1985}{}} \newlabel{subsec:matching-envelopes@cref}{{[subsection][3][26]26.3}{[1][425][]425}{}{}{}} \newlabel{prop:record:matching}{{26.5}{426}{Matching envelopes and the matching exponent}{proposition.1988}{}} \newlabel{prop:record:matching@cref}{{[proposition][5][26]26.5}{[1][426][]426}{}{}{}} \newlabel{subsec:cm-selected}{{26.4}{427}{The common mean for the selected law}{subsection.1992}{}} \newlabel{subsec:cm-selected@cref}{{[subsection][4][26]26.4}{[1][427][]427}{}{}{}} \newlabel{eq:record:cm-selected}{{26.2}{428}{The common mean for the selected law}{equation.1993}{}} \newlabel{eq:record:cm-selected@cref}{{[equation][2][26]26.2}{[1][428][]428}{}{}{}} \newlabel{subsec:record:positive_means}{{26.5}{428}{Mean energies exceed \texorpdfstring {$mY$}{mY} with \texorpdfstring {$m>1$}{m>1}}{subsection.1994}{}} \newlabel{subsec:record:positive_means@cref}{{[subsection][5][26]26.5}{[1][428][]428}{}{}{}} \newlabel{lem:record:companion-energy}{{26.6}{429}{Restored companion energies}{lemma.1997}{}} \newlabel{lem:record:companion-energy@cref}{{[lemma][6][26]26.6}{[1][429][]429}{}{}{}} \newlabel{prop:record:mean-credit}{{26.7}{429}{Mean credit}{proposition.2001}{}} \newlabel{prop:record:mean-credit@cref}{{[proposition][7][26]26.7}{[1][429][]429}{}{}{}} \newlabel{eq:mean-credit}{{26.3}{429}{Mean credit}{equation.2002}{}} \newlabel{eq:mean-credit@cref}{{[equation][3][26]26.3}{[1][429][]429}{}{}{}} \newlabel{subsec:joint-mean}{{26.6}{431}{Allocating the full positive mean jointly with the comparison}{subsection.2003}{}} \newlabel{subsec:joint-mean@cref}{{[subsection][6][26]26.6}{[1][431][]431}{}{}{}} \newlabel{eq:joint-resources}{{26.4}{431}{Allocating the full positive mean jointly with the comparison}{equation.2004}{}} \newlabel{eq:joint-resources@cref}{{[equation][4][26]26.4}{[1][431][]431}{}{}{}} \newlabel{lem:joint-multiaffine}{{26.8}{432}{Multiaffine allocation constants}{lemma.2006}{}} \newlabel{lem:joint-multiaffine@cref}{{[lemma][8][26]26.8}{[1][431][]432}{}{}{}} \newlabel{prop:joint-middle-mean}{{26.9}{432}{Four disjoint middle allocations}{proposition.2008}{}} \newlabel{prop:joint-middle-mean@cref}{{[proposition][9][26]26.9}{[1][432][]432}{}{}{}} \newlabel{eq:joint-alpha}{{26.5}{432}{Four disjoint middle allocations}{equation.2009}{}} \newlabel{eq:joint-alpha@cref}{{[equation][5][26]26.5}{[1][432][]432}{}{}{}} \newlabel{eq:joint-middle}{{26.6}{432}{Four disjoint middle allocations}{equation.2010}{}} \newlabel{eq:joint-middle@cref}{{[equation][6][26]26.6}{[1][432][]432}{}{}{}} \newlabel{prop:joint-upper-mean}{{26.10}{434}{Mean terms with a nonempty upper support}{proposition.2017}{}} \newlabel{prop:joint-upper-mean@cref}{{[proposition][10][26]26.10}{[1][434][]434}{}{}{}} \newlabel{sec:upper-reference}{{27}{435}{Upper primes I: the reference law \texorpdfstring {$\mu $}{mu} and its spectral bounds}{section.2020}{}} \newlabel{sec:upper-reference@cref}{{[section][27][]27}{[1][435][]435}{}{}{}} \newlabel{subsec:upper-bands}{{27.1}{436}{The \texorpdfstring {$310$}{310} bands and their input data}{subsection.2022}{}} \newlabel{subsec:upper-bands@cref}{{[subsection][1][27]27.1}{[1][436][]436}{}{}{}} \newlabel{def:record:upper-bands}{{27.1}{437}{Upper bands}{definition.2026}{}} \newlabel{def:record:upper-bands@cref}{{[definition][1][27]27.1}{[1][437][]437}{}{}{}} \newlabel{eq:upper-slice}{{27.1}{437}{Upper bands}{equation.2031}{}} \newlabel{eq:upper-slice@cref}{{[equation][1][27]27.1}{[1][437][]437}{}{}{}} \newlabel{eq:independent-fold-domination}{{27.2}{437}{Upper bands}{equation.2032}{}} \newlabel{eq:independent-fold-domination@cref}{{[equation][2][27]27.2}{[1][437][]437}{}{}{}} \newlabel{rem:upper-band-choices}{{27.2}{438}{What is a choice}{remark.2035}{}} \newlabel{rem:upper-band-choices@cref}{{[remark][2][27]27.2}{[1][438][]438}{}{}{}} \newlabel{rem:band-endpoints}{{27.3}{438}{Band endpoints}{remark.2037}{}} \newlabel{rem:band-endpoints@cref}{{[remark][3][27]27.3}{[1][438][]438}{}{}{}} \newlabel{subsec:upper-two-layer}{{27.2}{438}{The two-layer reference}{subsection.2038}{}} \newlabel{subsec:upper-two-layer@cref}{{[subsection][2][27]27.2}{[1][438][]438}{}{}{}} \newlabel{subsec:push:layer72spectral}{{27.2.1}{438}{The two-layer graphs}{subsubsection.2039}{}} \newlabel{subsec:push:layer72spectral@cref}{{[subsubsection][1][27,2]27.2.1}{[1][438][]438}{}{}{}} \newlabel{lem:upper-geometry}{{27.4}{439}{Two-layer geometry}{lemma.2042}{}} \newlabel{lem:upper-geometry@cref}{{[lemma][4][27]27.4}{[1][439][]439}{}{}{}} \newlabel{subsec:layer72:upper}{{27.2.2}{439}{The \texorpdfstring {$25$}{25} summand types}{subsubsection.2047}{}} \newlabel{subsec:layer72:upper@cref}{{[subsubsection][2][27,2]27.2.2}{[1][439][]439}{}{}{}} \newlabel{subsec:independent-fold-weights}{{27.2.3}{440}{The reference law \texorpdfstring {$\mu _\Blk $}{mu\_B} and its weights}{subsubsection.2048}{}} \newlabel{subsec:independent-fold-weights@cref}{{[subsubsection][3][27,2]27.2.3}{[1][440][]440}{}{}{}} \newlabel{def:upper-reference}{{27.5}{440}{The upper reference}{definition.2050}{}} \newlabel{def:upper-reference@cref}{{[definition][5][27]27.5}{[1][440][]440}{}{}{}} \newlabel{eq:independent-fold-polynomial}{{27.3}{440}{The upper reference}{equation.2051}{}} \newlabel{eq:independent-fold-polynomial@cref}{{[equation][3][27]27.3}{[1][440][]440}{}{}{}} \newlabel{subsec:record:upper_root}{{27.3}{440}{The two principal cuts}{subsection.2052}{}} \newlabel{subsec:record:upper_root@cref}{{[subsection][3][27]27.3}{[1][440][]440}{}{}{}} \newlabel{eq:upper-signed-collision-counts}{{27.4}{440}{The setting}{equation.2054}{}} \newlabel{eq:upper-signed-collision-counts@cref}{{[equation][4][27]27.4}{[1][440][]440}{}{}{}} \newlabel{lem:record:direct-star-inputs}{{27.6}{441}{Root inputs}{lemma.2057}{}} \newlabel{lem:record:direct-star-inputs@cref}{{[lemma][6][27]27.6}{[1][441][]441}{}{}{}} \newlabel{lem:record:monotone-endpoint}{{27.7}{441}{Monotone endpoint extension}{lemma.2063}{}} \newlabel{lem:record:monotone-endpoint@cref}{{[lemma][7][27]27.7}{[1][441][]441}{}{}{}} \newlabel{cert:record:direct-star}{{27.8}{442}{Route~B star-synthesis bounds and Schur tests at the root cuts}{certificate.2065}{}} \newlabel{cert:record:direct-star@cref}{{[certificate][8][27]27.8}{[1][442][]442}{}{}{}} \newlabel{cert:upper-root-caps}{{27.9}{443}{Root caps below $2^{52}$}{certificate.2069}{}} \newlabel{cert:upper-root-caps@cref}{{[certificate][9][27]27.9}{[1][443][]443}{}{}{}} \newlabel{lem:upper-completed-root}{{27.10}{444}{Completed-root caps}{lemma.2073}{}} \newlabel{lem:upper-completed-root@cref}{{[lemma][10][27]27.10}{[1][444][]444}{}{}{}} \newlabel{cert:upper-completed-root}{{27.11}{445}{Completed-root caps}{certificate.2077}{}} \newlabel{cert:upper-completed-root@cref}{{[certificate][11][27]27.11}{[1][445][]445}{}{}{}} \newlabel{subsec:upper-cross-weighted}{{27.3.1}{445}{Cross-weighted root refinement and the final reference}{subsubsection.2078}{}} \newlabel{subsec:upper-cross-weighted@cref}{{[subsubsection][1][27,3]27.3.1}{[1][445][]445}{}{}{}} \newlabel{lem:upper-cross-divisors}{{27.12}{445}{Uniform extraction divisors}{lemma.2080}{}} \newlabel{lem:upper-cross-divisors@cref}{{[lemma][12][27]27.12}{[1][445][]445}{}{}{}} \newlabel{subsec:upper-nonroot}{{27.4}{446}{The ten non-principal cuts}{subsection.2081}{}} \newlabel{subsec:upper-nonroot@cref}{{[subsection][4][27]27.4}{[1][446][]446}{}{}{}} \newlabel{cert:upper-band-inputs}{{27.13}{447}{Band inputs}{certificate.2083}{}} \newlabel{cert:upper-band-inputs@cref}{{[certificate][13][27]27.13}{[1][447][]447}{}{}{}} \newlabel{subsec:upper-observed}{{27.5}{448}{Merge and constant bounds for four states}{subsection.2088}{}} \newlabel{subsec:upper-observed@cref}{{[subsection][5][27]27.5}{[1][448][]448}{}{}{}} \newlabel{prop:observed-caps}{{27.14}{448}{Observed merge and constant caps}{proposition.2090}{}} \newlabel{prop:observed-caps@cref}{{[proposition][14][27]27.14}{[1][448][]448}{}{}{}} \newlabel{subsec:upper-rows}{{27.6}{450}{Conditional laws given the middle label}{subsection.2091}{}} \newlabel{subsec:upper-rows@cref}{{[subsection][6][27]27.6}{[1][450][]450}{}{}{}} \newlabel{subsec:push:layer72product}{{27.6.1}{450}{The product reference and the star bounds}{subsubsection.2092}{}} \newlabel{subsec:push:layer72product@cref}{{[subsubsection][1][27,6]27.6.1}{[1][450][]450}{}{}{}} \newlabel{subsec:advance:product-rows}{{27.6.2}{451}{Differences of conditional laws given the middle label}{subsubsection.2093}{}} \newlabel{subsec:advance:product-rows@cref}{{[subsubsection][2][27,6]27.6.2}{[1][451][]451}{}{}{}} \newlabel{subsec:row-anova-correlation}{{27.6.3}{455}{Exact-support correlations}{subsubsection.2114}{}} \newlabel{subsec:row-anova-correlation@cref}{{[subsubsection][3][27,6]27.6.3}{[1][455][]455}{}{}{}} \newlabel{eq:row-anova-stars}{{27.5}{455}{Exact-support correlations}{equation.2115}{}} \newlabel{eq:row-anova-stars@cref}{{[equation][5][27]27.5}{[1][455][]455}{}{}{}} \newlabel{eq:row-anova-actual}{{27.6}{455}{Exact-support correlations}{equation.2116}{}} \newlabel{eq:row-anova-actual@cref}{{[equation][6][27]27.6}{[1][455][]455}{}{}{}} \newlabel{subsec:upper-joint-rows}{{27.6.4}{456}{Fold and matching conditional laws bounded jointly}{subsubsection.2118}{}} \newlabel{subsec:upper-joint-rows@cref}{{[subsubsection][4][27,6]27.6.4}{[1][455][]456}{}{}{}} \newlabel{lem:joint-pins}{{27.15}{456}{Pin classes of the $\rm L$ rows}{lemma.2120}{}} \newlabel{lem:joint-pins@cref}{{[lemma][15][27]27.15}{[1][456][]456}{}{}{}} \newlabel{prop:joint-row-floor}{{27.16}{457}{A necessary floor for the chosen joint-row formula}{proposition.2124}{}} \newlabel{prop:joint-row-floor@cref}{{[proposition][16][27]27.16}{[1][457][]457}{}{}{}} \newlabel{subsec:upper-formulas}{{27.7}{458}{Band input formulas (F1)--(F6) and (F10): definitions}{subsection.2125}{}} \newlabel{subsec:upper-formulas@cref}{{[subsection][7][27]27.7}{[1][458][]458}{}{}{}} \newlabel{it:record:upper-F1}{{{{\textup {(F1)}}}}{458}{Band input formulas (F1)--(F6) and (F10): definitions}{Item.2126}{}} \newlabel{it:record:upper-F1@cref}{{[enumi][1][]{{\textup {(F1)}}}}{[1][458][]458}{}{}{}} \newlabel{it:record:upper-F2}{{{{\textup {(F2)}}}}{458}{Band input formulas (F1)--(F6) and (F10): definitions}{Item.2127}{}} \newlabel{it:record:upper-F2@cref}{{[enumi][2][]{{\textup {(F2)}}}}{[1][458][]458}{}{}{}} \newlabel{it:record:upper-F3}{{{{\textup {(F3)}}}}{458}{Band input formulas (F1)--(F6) and (F10): definitions}{Item.2128}{}} \newlabel{it:record:upper-F3@cref}{{[enumi][3][]{{\textup {(F3)}}}}{[1][458][]458}{}{}{}} \newlabel{it:record:upper-F4}{{{{\textup {(F4)}}}}{458}{Band input formulas (F1)--(F6) and (F10): definitions}{Item.2129}{}} \newlabel{it:record:upper-F4@cref}{{[enumi][4][]{{\textup {(F4)}}}}{[1][458][]458}{}{}{}} \newlabel{it:record:upper-F5}{{{{\textup {(F5)}}}}{458}{Band input formulas (F1)--(F6) and (F10): definitions}{Item.2130}{}} \newlabel{it:record:upper-F5@cref}{{[enumi][5][]{{\textup {(F5)}}}}{[1][458][]458}{}{}{}} \newlabel{it:record:upper-F6}{{{{\textup {(F6)}}}}{459}{Band input formulas (F1)--(F6) and (F10): definitions}{Item.2131}{}} \newlabel{it:record:upper-F6@cref}{{[enumi][6][]{{\textup {(F6)}}}}{[1][459][]459}{}{}{}} \newlabel{it:record:upper-F10}{{{{\textup {(F10)}}}}{459}{Band input formulas (F1)--(F6) and (F10): definitions}{Item.2132}{}} \newlabel{it:record:upper-F10@cref}{{[enumi][10][]{{\textup {(F10)}}}}{[1][459][]459}{}{}{}} \newlabel{subsec:upper-reference-rp}{{27.8}{460}{(CP1) for upper atoms}{subsection.2133}{}} \newlabel{subsec:upper-reference-rp@cref}{{[subsection][8][27]27.8}{[1][460][]460}{}{}{}} \newlabel{it:upper-valid-root}{{{{(V1)}}}{460}{(CP1) for upper atoms}{Item.2134}{}} \newlabel{it:upper-valid-root@cref}{{[enumi][1][]{{(V1)}}}{[1][460][]460}{}{}{}} \newlabel{it:upper-valid-rows}{{{{(V2)}}}{460}{(CP1) for upper atoms}{Item.2135}{}} \newlabel{it:upper-valid-rows@cref}{{[enumi][2][]{{(V2)}}}{[1][460][]460}{}{}{}} \newlabel{it:upper-valid-layer}{{{{(V3)}}}{460}{(CP1) for upper atoms}{Item.2136}{}} \newlabel{it:upper-valid-layer@cref}{{[enumi][3][]{{(V3)}}}{[1][460][]460}{}{}{}} \newlabel{lem:upper-reference-rp}{{27.17}{460}{The upper reference}{lemma.2138}{}} \newlabel{lem:upper-reference-rp@cref}{{[lemma][17][27]27.17}{[1][460][]460}{}{}{}} \newlabel{cert:upper-completion}{{27.18}{461}{Completion and domination gates}{certificate.2142}{}} \newlabel{cert:upper-completion@cref}{{[certificate][18][27]27.18}{[1][461][]461}{}{}{}} \newlabel{sec:upper-comparison}{{28}{463}{Upper primes II: the comparison law \texorpdfstring {$\nu $}{nu} and prices \texorpdfstring {$S_{\rm u},A_{\rm u}$}{S\_u,A\_u}}{section.2145}{}} \newlabel{sec:upper-comparison@cref}{{[section][28][]28}{[1][462][]463}{}{}{}} \newlabel{sec:frontier:upper-oneway}{{28.1}{463}{One-way replacements imposing twelve projected pairs}{subsection.2147}{}} \newlabel{sec:frontier:upper-oneway@cref}{{[subsection][1][28]28.1}{[1][463][]463}{}{}{}} \newlabel{eq:upper-twelve}{{28.1}{463}{Queries and records}{equation.2149}{}} \newlabel{eq:upper-twelve@cref}{{[equation][1][28]28.1}{[1][463][]463}{}{}{}} \newlabel{lem:six-query-retention}{{28.1}{464}{Records that accept the six queries}{lemma.2151}{}} \newlabel{lem:six-query-retention@cref}{{[lemma][1][28]28.1}{[1][464][]464}{}{}{}} \newlabel{it:record:upper-F7}{{{{\textup {(F7)}}}}{465}{The repair formula}{Item.2154}{}} \newlabel{it:record:upper-F7@cref}{{[enumi][7][]{{\textup {(F7)}}}}{[1][465][]465}{}{}{}} \newlabel{subsec:upper-stars}{{28.2}{466}{Star terms in the one-way replacements}{subsection.2155}{}} \newlabel{subsec:upper-stars@cref}{{[subsection][2][28]28.2}{[1][466][]466}{}{}{}} \newlabel{lem:upper-stars}{{28.2}{467}{Upper stars}{lemma.2158}{}} \newlabel{lem:upper-stars@cref}{{[lemma][2][28]28.2}{[1][467][]467}{}{}{}} \newlabel{eq:frontier:all-prime-star-cap}{{28.2}{468}{Upper stars}{equation.2161}{}} \newlabel{eq:frontier:all-prime-star-cap@cref}{{[equation][2][28]28.2}{[1][468][]468}{}{}{}} \newlabel{it:record:upper-F8}{{{{\textup {(F8)}}}}{470}{Setting}{Item.2164}{}} \newlabel{it:record:upper-F8@cref}{{[enumi][8][]{{\textup {(F8)}}}}{[1][470][]470}{}{}{}} \newlabel{subsec:upper-actual-frames}{{28.3}{471}{Replacements keeping the old cross edges}{subsection.2165}{}} \newlabel{subsec:upper-actual-frames@cref}{{[subsection][3][28]28.3}{[1][471][]471}{}{}{}} \newlabel{prop:forest-records}{{28.3}{471}{Degree-two FF, FE and EF records}{proposition.2168}{}} \newlabel{prop:forest-records@cref}{{[proposition][3][28]28.3}{[1][471][]471}{}{}{}} \newlabel{def:dense-comparison}{{28.4}{473}{Softened laws}{definition.2174}{}} \newlabel{def:dense-comparison@cref}{{[definition][4][28]28.4}{[1][473][]473}{}{}{}} \newlabel{prop:dense-comparison}{{28.5}{474}{Replacements keeping the old cross edges}{proposition.2176}{}} \newlabel{prop:dense-comparison@cref}{{[proposition][5][28]28.5}{[1][474][]474}{}{}{}} \newlabel{prop:le-mixture}{{28.6}{476}{Replacing an LE record by a positive mixture of four dense laws}{proposition.2182}{}} \newlabel{prop:le-mixture@cref}{{[proposition][6][28]28.6}{[1][476][]476}{}{}{}} \newlabel{it:record:upper-F9}{{{{\textup {(F9)}}}}{477}{The formula}{Item.2184}{}} \newlabel{it:record:upper-F9@cref}{{[enumi][9][]{{\textup {(F9)}}}}{[1][477][]477}{}{}{}} \newlabel{subsec:upper-six-refinements}{{28.4}{477}{Complete six-query refinements used in the final closing}{subsection.2185}{}} \newlabel{subsec:upper-six-refinements@cref}{{[subsection][4][28]28.4}{[1][477][]477}{}{}{}} \newlabel{prop:upper-soft-nine}{{28.7}{478}{Soft nine-label comparisons}{proposition.2187}{}} \newlabel{prop:upper-soft-nine@cref}{{[proposition][7][28]28.7}{[1][478][]478}{}{}{}} \newlabel{prop:upper-ss-six}{{28.8}{480}{The six-query SS comparison}{proposition.2189}{}} \newlabel{prop:upper-ss-six@cref}{{[proposition][8][28]28.8}{[1][480][]480}{}{}{}} \newlabel{prop:upper-constant-six}{{28.9}{480}{Constant-emission comparisons}{proposition.2191}{}} \newlabel{prop:upper-constant-six@cref}{{[proposition][9][28]28.9}{[1][480][]480}{}{}{}} \newlabel{prop:upper-observed-dense}{{28.10}{481}{Dense comparisons after emission}{proposition.2193}{}} \newlabel{prop:upper-observed-dense@cref}{{[proposition][10][28]28.10}{[1][481][]481}{}{}{}} \newlabel{subsec:upper-domain}{{28.5}{482}{A bound at a band start holds at every larger prime in the band}{subsection.2194}{}} \newlabel{subsec:upper-domain@cref}{{[subsection][5][28]28.5}{[1][482][]482}{}{}{}} \newlabel{lem:record:domain}{{28.11}{482}{Domain of the upper formulas}{lemma.2196}{}} \newlabel{lem:record:domain@cref}{{[lemma][11][28]28.11}{[1][482][]482}{}{}{}} \newlabel{it:record:upper-G1}{{{{\textup {(G1)}}}}{482}{Domain of the upper formulas}{Item.2197}{}} \newlabel{it:record:upper-G1@cref}{{[enumi][1][]{{\textup {(G1)}}}}{[1][482][]482}{}{}{}} \newlabel{it:record:upper-G2}{{{{\textup {(G2)}}}}{482}{Domain of the upper formulas}{Item.2198}{}} \newlabel{it:record:upper-G2@cref}{{[enumi][2][]{{\textup {(G2)}}}}{[1][482][]482}{}{}{}} \newlabel{it:record:upper-G3}{{{{\textup {(G3)}}}}{482}{Domain of the upper formulas}{Item.2199}{}} \newlabel{it:record:upper-G3@cref}{{[enumi][3][]{{\textup {(G3)}}}}{[1][482][]482}{}{}{}} \newlabel{it:record:upper-G4}{{{{\textup {(G4)}}}}{482}{Domain of the upper formulas}{Item.2200}{}} \newlabel{it:record:upper-G4@cref}{{[enumi][4][]{{\textup {(G4)}}}}{[1][482][]482}{}{}{}} \newlabel{it:record:upper-G5}{{{{\textup {(G5)}}}}{482}{Domain of the upper formulas}{Item.2201}{}} \newlabel{it:record:upper-G5@cref}{{[enumi][5][]{{\textup {(G5)}}}}{[1][482][]482}{}{}{}} \newlabel{it:record:upper-G6}{{{{\textup {(G6)}}}}{482}{Domain of the upper formulas}{Item.2202}{}} \newlabel{it:record:upper-G6@cref}{{[enumi][6][]{{\textup {(G6)}}}}{[1][482][]482}{}{}{}} \newlabel{it:record:upper-G7}{{{{\textup {(G7)}}}}{482}{Domain of the upper formulas}{Item.2203}{}} \newlabel{it:record:upper-G7@cref}{{[enumi][7][]{{\textup {(G7)}}}}{[1][482][]482}{}{}{}} \newlabel{eq:upper-block-gate}{{28.3}{484}{A bound at a band start holds at every larger prime in the band}{equation.2207}{}} \newlabel{eq:upper-block-gate@cref}{{[equation][3][28]28.3}{[1][484][]484}{}{}{}} \newlabel{cert:upper-lower-bands}{{28.12}{485}{The bands below $2^{48}$}{certificate.2210}{}} \newlabel{cert:upper-lower-bands@cref}{{[certificate][12][28]28.12}{[1][485][]485}{}{}{}} \newlabel{subsec:upper-prices}{{28.6}{486}{(CP4) for upper atoms with prices \texorpdfstring {$S_{\rm u},A_{\rm u}$}{S\_u,A\_u}}{subsection.2217}{}} \newlabel{subsec:upper-prices@cref}{{[subsection][6][28]28.6}{[1][486][]486}{}{}{}} \newlabel{def:upper-comparison}{{28.13}{486}{The upper comparison law}{definition.2219}{}} \newlabel{def:upper-comparison@cref}{{[definition][13][28]28.13}{[1][486][]486}{}{}{}} \newlabel{prop:record:upper}{{28.14}{487}{(CP4) in the upper range: the totals $S_{\rm u}$ and $A_{\rm u}$}{proposition.2224}{}} \newlabel{prop:record:upper@cref}{{[proposition][14][28]28.14}{[1][487][]487}{}{}{}} \newlabel{lem:upper:neumann-refinement}{{28.15}{488}{One initial term in the upper marginal repair}{lemma.2229}{}} \newlabel{lem:upper:neumann-refinement@cref}{{[lemma][15][28]28.15}{[1][488][]488}{}{}{}} \newlabel{sec:tail-index}{{29}{490}{Large primes \texorpdfstring {$p\ge 2^{512}$}{p >= 2\textasciicircum 512} and the external index}{section.2233}{}} \newlabel{sec:tail-index@cref}{{[section][29][]29}{[1][490][]490}{}{}{}} \newlabel{subsec:tail-law}{{29.1}{490}{The reference law at one large prime}{subsection.2235}{}} \newlabel{subsec:tail-law@cref}{{[subsection][1][29]29.1}{[1][490][]490}{}{}{}} \newlabel{def:tail-law}{{29.1}{490}{The tail law}{definition.2237}{}} \newlabel{def:tail-law@cref}{{[definition][1][29]29.1}{[1][490][]490}{}{}{}} \newlabel{eq:tail-coefficients}{{29.1}{491}{The tail law}{equation.2238}{}} \newlabel{eq:tail-coefficients@cref}{{[equation][1][29]29.1}{[1][491][]491}{}{}{}} \newlabel{lem:tail-law}{{29.2}{491}{The tail reference}{lemma.2240}{}} \newlabel{lem:tail-law@cref}{{[lemma][2][29]29.2}{[1][491][]491}{}{}{}} \newlabel{subsec:tail-mixing}{{29.2}{492}{Mixing at the tail primes}{subsection.2244}{}} \newlabel{subsec:tail-mixing@cref}{{[subsection][2][29]29.2}{[1][491][]492}{}{}{}} \newlabel{lem:record:tail-mixing}{{29.3}{492}{Tail mixing}{lemma.2246}{}} \newlabel{lem:record:tail-mixing@cref}{{[lemma][3][29]29.3}{[1][492][]492}{}{}{}} \newlabel{subsec:tail-prices}{{29.3}{492}{Comparison prices \texorpdfstring {$O(p^{-3/2+2a})$}{O(p\textasciicircum (-3/2+2a))} at large primes}{subsection.2250}{}} \newlabel{subsec:tail-prices@cref}{{[subsection][3][29]29.3}{[1][492][]492}{}{}{}} \newlabel{eq:tail-polynomials}{{29.2}{493}{Comparison prices \texorpdfstring {$O(p^{-3/2+2a})$}{O(p\textasciicircum (-3/2+2a))} at large primes}{equation.2251}{}} \newlabel{eq:tail-polynomials@cref}{{[equation][2][29]29.2}{[1][493][]493}{}{}{}} \newlabel{cert:tail-caps}{{29.4}{493}{The tail repair caps}{certificate.2253}{}} \newlabel{cert:tail-caps@cref}{{[certificate][4][29]29.4}{[1][493][]493}{}{}{}} \newlabel{lem:tail-prices}{{29.5}{493}{The tail comparison law and its prices}{lemma.2255}{}} \newlabel{lem:tail-prices@cref}{{[lemma][5][29]29.5}{[1][493][]493}{}{}{}} \newlabel{subsec:index-law}{{29.4}{494}{The external index by exact conductor}{subsection.2260}{}} \newlabel{subsec:index-law@cref}{{[subsection][4][29]29.4}{[1][494][]494}{}{}{}} \newlabel{lem:imp:padic-envelope}{{29.6}{494}{Finite conductor-depth index envelope}{lemma.2262}{}} \newlabel{lem:imp:padic-envelope@cref}{{[lemma][6][29]29.6}{[1][494][]494}{}{}{}} \newlabel{prop:imp:padic-price}{{29.7}{495}{Finite p-adic matching and wrap prices}{proposition.2264}{}} \newlabel{prop:imp:padic-price@cref}{{[proposition][7][29]29.7}{[1][495][]495}{}{}{}} \newlabel{prop:oct24-index-cost}{{29.7}{495}{Finite p-adic matching and wrap prices}{proposition.2264}{}} \newlabel{prop:oct24-index-cost@cref}{{[proposition][7][29]29.7}{[1][495][]495}{}{}{}} \newlabel{eq:oct24-index-cost}{{29.3}{496}{Finite p-adic matching and wrap prices}{equation.2265}{}} \newlabel{eq:oct24-index-cost@cref}{{[equation][3][29]29.3}{[1][496][]496}{}{}{}} \newlabel{cor:imp:padic-majorant}{{29.8}{496}{A compact upper majorant}{corollary.2267}{}} \newlabel{cor:imp:padic-majorant@cref}{{[corollary][8][29]29.8}{[1][496][]496}{}{}{}} \newlabel{eq:oct24-moment}{{29.4}{497}{Evaluating \texorpdfstring {$R_I$}{R\_I}, \texorpdfstring {$J$}{J} and \texorpdfstring {$W$}{W}}{equation.2269}{}} \newlabel{eq:oct24-moment@cref}{{[equation][4][29]29.4}{[1][497][]497}{}{}{}} \newlabel{lem:index-moments}{{29.9}{497}{Finite prime moments}{lemma.2271}{}} \newlabel{lem:index-moments@cref}{{[lemma][9][29]29.9}{[1][497][]497}{}{}{}} \newlabel{rem:index-convexity}{{29.10}{498}{The choice of $K$}{remark.2273}{}} \newlabel{rem:index-convexity@cref}{{[remark][10][29]29.10}{[1][498][]498}{}{}{}} \newlabel{cert:index-moment}{{29.11}{498}{The index moment}{certificate.2275}{}} \newlabel{cert:index-moment@cref}{{[certificate][11][29]29.11}{[1][498][]498}{}{}{}} \newlabel{sec:closing}{{30}{498}{Baseline closing: \texorpdfstring {$\Theta <1$}{Theta<1} with \texorpdfstring {$\theta =1$}{theta=1}}{section.2278}{}} \newlabel{sec:closing@cref}{{[section][30][]30}{[1][498][]498}{}{}{}} \newlabel{subsec:closing-quantities}{{30.1}{499}{Definitions of \texorpdfstring {$L_0,S,A,D,\mathcal E,T,R_I,J,W,m$}{L\_0,S,A,D,E,T,R\_I,J,W,m} (baseline)}{subsection.2280}{}} \newlabel{subsec:closing-quantities@cref}{{[subsection][1][30]30.1}{[1][499][]499}{}{}{}} \newlabel{def:closing-quantities}{{30.1}{499}{The closing quantities}{definition.2282}{}} \newlabel{def:closing-quantities@cref}{{[definition][1][30]30.1}{[1][499][]499}{}{}{}} \newlabel{prop:closing-data}{{30.2}{502}{The closing quantities bound the data of the comparison theorem}{proposition.2297}{}} \newlabel{prop:closing-data@cref}{{[proposition][2][30]30.2}{[1][501][]502}{}{}{}} \newlabel{tab:closing-values}{{12}{504}{The closing quantities, rounded outward from the certificate's enclosures ($<$ upper bound, $>$ lower bound, $\ldots $ exactly defined). The certificate evaluates $\Theta $ from the full enclosures, not from these values}{table.2304}{}} \newlabel{tab:closing-values@cref}{{[table][12][]12}{[1][504][]504}{}{}{}} \newlabel{subsec:closing-certificate}{{30.2}{504}{Outward-interval evaluation: \texorpdfstring {$\Theta <\PushTheta $}{Theta<\PushTheta }}{subsection.2305}{}} \newlabel{subsec:closing-certificate@cref}{{[subsection][2][30]30.2}{[1][504][]504}{}{}{}} \newlabel{cert:closing}{{30.3}{504}{The closing}{certificate.2307}{}} \newlabel{cert:closing@cref}{{[certificate][3][30]30.3}{[1][504][]504}{}{}{}} \newlabel{subsec:proof-main}{{30.3}{505}{Proof of the baseline (\texorpdfstring {$\theta =1$}{theta=1}) by Theorem~C}{subsection.2309}{}} \newlabel{subsec:proof-main@cref}{{[subsection][3][30]30.3}{[1][505][]505}{}{}{}} \newlabel{sec:density:moments-prefix}{{31}{506}{Stronger density estimates: multilinear bounds and a new prefix law}{section.2312}{}} \newlabel{sec:density:moments-prefix@cref}{{[section][31][]31}{[1][506][]506}{}{}{}} \newlabel{def:density:mixed-moment}{{31.1}{506}{Unit mixed moment}{definition.2315}{}} \newlabel{def:density:mixed-moment@cref}{{[definition][1][31]31.1}{[1][506][]506}{}{}{}} \newlabel{lem:density:uniform-convexity}{{31.2}{506}{Uniform convexity}{lemma.2318}{}} \newlabel{lem:density:uniform-convexity@cref}{{[lemma][2][31]31.2}{[1][506][]506}{}{}{}} \newlabel{lem:density:typed-mixture}{{31.3}{506}{Typed finite-alphabet mixture}{lemma.2320}{}} \newlabel{lem:density:typed-mixture@cref}{{[lemma][3][31]31.3}{[1][506][]506}{}{}{}} \newlabel{eq:density:typed-mixture-coarse}{{31.1}{507}{Typed finite-alphabet mixture}{equation.2321}{}} \newlabel{eq:density:typed-mixture-coarse@cref}{{[equation][1][31]31.1}{[1][507][]507}{}{}{}} \newlabel{lem:density:edge-moment}{{31.4}{507}{Square-pair moment}{lemma.2324}{}} \newlabel{lem:density:edge-moment@cref}{{[lemma][4][31]31.4}{[1][507][]507}{}{}{}} \newlabel{eq:density:edge-integer-gate}{{31.2}{507}{Square-pair moment}{equation.2325}{}} \newlabel{eq:density:edge-integer-gate@cref}{{[equation][2][31]31.2}{[1][507][]507}{}{}{}} \newlabel{lem:density:invariant-pair}{{31.5}{508}{Invariant distinct pairs}{corollary.2327}{}} \newlabel{lem:density:invariant-pair@cref}{{[corollary][5][31]31.5}{[1][508][]508}{}{}{}} \newlabel{lem:density:clique36}{{31.6}{508}{Thirty-six digit-clique draws}{lemma.2329}{}} \newlabel{lem:density:clique36@cref}{{[lemma][6][31]31.6}{[1][508][]508}{}{}{}} \newlabel{eq:density:clique-denominator}{{31.3}{508}{A pair moment and independent draws from a digit clique}{equation.2332}{}} \newlabel{eq:density:clique-denominator@cref}{{[equation][3][31]31.3}{[1][508][]508}{}{}{}} \newlabel{eq:density:clique-binomial-gate}{{31.4}{508}{A pair moment and independent draws from a digit clique}{equation.2333}{}} \newlabel{eq:density:clique-binomial-gate@cref}{{[equation][4][31]31.4}{[1][508][]508}{}{}{}} \newlabel{lem:density:clique-copies}{{31.7}{509}{At most two copies per label}{lemma.2335}{}} \newlabel{lem:density:clique-copies@cref}{{[lemma][7][31]31.7}{[1][509][]509}{}{}{}} \newlabel{thm:density:iid-prefix}{{31.8}{509}{A prefix with density endpoint $51/50$}{theorem.2338}{}} \newlabel{thm:density:iid-prefix@cref}{{[theorem][8][31]31.8}{[1][509][]509}{}{}{}} \newlabel{sec:density-upgrade}{{32}{511}{Induction with density exponent \texorpdfstring {$\vartheta >1$}{vartheta>1}}{section.2345}{}} \newlabel{sec:density-upgrade@cref}{{[section][32][]32}{[1][511][]511}{}{}{}} \newlabel{eq:density:parameter-range}{{32.1}{511}{What this section proves and how to read it}{equation.2347}{}} \newlabel{eq:density:parameter-range@cref}{{[equation][1][32]32.1}{[1][511][]511}{}{}{}} \newlabel{lem:density:repeated-pair}{{32.1}{511}{A repeated distinct pair}{lemma.2350}{}} \newlabel{lem:density:repeated-pair@cref}{{[lemma][1][32]32.1}{[1][511][]511}{}{}{}} \newlabel{lem:density:middle-catalog}{{32.2}{512}{The nonconstant middle catalog}{lemma.2352}{}} \newlabel{lem:density:middle-catalog@cref}{{[lemma][2][32]32.2}{[1][512][]512}{}{}{}} \newlabel{lem:density:conditioning}{{32.3}{513}{A collision conditioning bound}{lemma.2354}{}} \newlabel{lem:density:conditioning@cref}{{[lemma][3][32]32.3}{[1][513][]513}{}{}{}} \newlabel{eq:density:conditioning-gate}{{32.2}{513}{A collision conditioning bound}{equation.2355}{}} \newlabel{eq:density:conditioning-gate@cref}{{[equation][2][32]32.2}{[1][513][]513}{}{}{}} \newlabel{lem:density:strong-F}{{32.4}{513}{Moments for weighted fold restoration}{lemma.2357}{}} \newlabel{lem:density:strong-F@cref}{{[lemma][4][32]32.4}{[1][513][]513}{}{}{}} \newlabel{lem:density:joint-block-gate}{{32.5}{514}{Joint block-size moment gate}{lemma.2360}{}} \newlabel{lem:density:joint-block-gate@cref}{{[lemma][5][32]32.5}{[1][514][]514}{}{}{}} \newlabel{eq:density:joint-block-gate}{{32.3}{514}{Joint block-size moment gate}{equation.2361}{}} \newlabel{eq:density:joint-block-gate@cref}{{[equation][3][32]32.3}{[1][514][]514}{}{}{}} \newlabel{lem:density:packets}{{32.6}{515}{The selected packet gates}{lemma.2363}{}} \newlabel{lem:density:packets@cref}{{[lemma][6][32]32.6}{[1][515][]515}{}{}{}} \newlabel{eq:density:middle-bad-fractions}{{32.4}{515}{Concentrated packets: pinning rare constant labels}{equation.2364}{}} \newlabel{eq:density:middle-bad-fractions@cref}{{[equation][4][32]32.4}{[1][515][]515}{}{}{}} \newlabel{cert:density:packets}{{32.7}{516}{Packet arithmetic}{certificate.2366}{}} \newlabel{cert:density:packets@cref}{{[certificate][7][32]32.7}{[1][516][]516}{}{}{}} \newlabel{lem:density:coupled}{{32.8}{516}{Coupled spectator estimate}{lemma.2369}{}} \newlabel{lem:density:coupled@cref}{{[lemma][8][32]32.8}{[1][516][]516}{}{}{}} \newlabel{prop:density:production}{{32.9}{517}{Main terms at the improved parameters}{proposition.2371}{}} \newlabel{prop:density:production@cref}{{[proposition][9][32]32.9}{[1][517][]517}{}{}{}} \newlabel{lem:density:restoration}{{32.10}{519}{Density-sensitive restoration}{lemma.2374}{}} \newlabel{lem:density:restoration@cref}{{[lemma][10][32]32.10}{[1][519][]519}{}{}{}} \newlabel{eq:density:restoration}{{32.5}{519}{Density-sensitive restoration}{equation.2375}{}} \newlabel{eq:density:restoration@cref}{{[equation][5][32]32.5}{[1][519][]519}{}{}{}} \newlabel{lem:density:global-moment}{{32.11}{520}{An unconditional reference moment}{lemma.2378}{}} \newlabel{lem:density:global-moment@cref}{{[lemma][11][32]32.11}{[1][520][]520}{}{}{}} \newlabel{thm:density:induction}{{32.12}{520}{The upgraded induction}{theorem.2380}{}} \newlabel{thm:density:induction@cref}{{[theorem][12][32]32.12}{[1][520][]520}{}{}{}} \newlabel{sec:four-routes-closing}{{33}{521}{Improved closing: \texorpdfstring {$\Theta <\FourRoutesTheta $}{Theta<\FourRoutesTheta } with \texorpdfstring {$\vartheta =\FourRoutesDensity $}{vartheta=\FourRoutesDensity }}{section.2381}{}} \newlabel{sec:four-routes-closing@cref}{{[section][33][]33}{[1][521][]521}{}{}{}} \newlabel{eq:four-routes-normalizer}{{33.1}{522}{Accounting for the normalizing factor \texorpdfstring {$Z_i^{-1}$}{Z\_i\textasciicircum (-1)}}{equation.2383}{}} \newlabel{eq:four-routes-normalizer@cref}{{[equation][1][33]33.1}{[1][521][]522}{}{}{}} \newlabel{lem:four-routes-normalized}{{33.1}{522}{Consistent normalized prices}{lemma.2385}{}} \newlabel{lem:four-routes-normalized@cref}{{[lemma][1][33]33.1}{[1][522][]522}{}{}{}} \newlabel{eq:four-routes-first}{{33.2}{522}{Consistent normalized prices}{equation.2386}{}} \newlabel{eq:four-routes-first@cref}{{[equation][2][33]33.2}{[1][522][]522}{}{}{}} \newlabel{eq:four-routes-q-reserve}{{33.3}{522}{Consistent normalized prices}{equation.2387}{}} \newlabel{eq:four-routes-q-reserve@cref}{{[equation][3][33]33.3}{[1][522][]522}{}{}{}} \newlabel{lem:four-routes-upper-normalized}{{33.2}{523}{Upper-band normalization}{lemma.2389}{}} \newlabel{lem:four-routes-upper-normalized@cref}{{[lemma][2][33]33.2}{[1][522][]523}{}{}{}} \newlabel{eq:four-routes-restoration}{{33.4}{523}{The selected laws and common assignments}{equation.2391}{}} \newlabel{eq:four-routes-restoration@cref}{{[equation][4][33]33.4}{[1][523][]523}{}{}{}} \newlabel{eq:final-joint-closing}{{33.5}{524}{The joint closing number}{equation.2393}{}} \newlabel{eq:final-joint-closing@cref}{{[equation][5][33]33.5}{[1][524][]524}{}{}{}} \newlabel{tab:four-routes-ledger}{{13}{524}{The improved closing ledger. Bounds are rounded outward from the complete enclosures; the closing uses the enclosures themselves}{table.2394}{}} \newlabel{tab:four-routes-ledger@cref}{{[table][13][]13}{[1][524][]524}{}{}{}} \newlabel{cert:four-routes-closing}{{33.3}{524}{The final joint closing}{certificate.2396}{}} \newlabel{cert:four-routes-closing@cref}{{[certificate][3][33]33.3}{[1][524][]524}{}{}{}} \newlabel{sec:history}{{34}{525}{How the construction developed}{section.2397}{}} \newlabel{sec:history@cref}{{[section][34][]34}{[1][525][]525}{}{}{}} \gdef \LT@v {\LT@entry {4}{14.25002pt}\LT@entry {1}{259.76178pt}\LT@entry {1}{180.76273pt}} \newlabel{subsec:history:checkpoints}{{34.1}{526}{The checkpoints}{subsection.2399}{}} \newlabel{subsec:history:checkpoints@cref}{{[subsection][1][34]34.1}{[1][525][]526}{}{}{}} \newlabel{tab:history:checkpoints}{{14}{526}{The checkpoints: $d$ slots, $k$ queries (edges amplified by repetition in the signed product; the first design couples nine pairs, one family at a time), density exponent $\theta $, functional exponent $a=(d-\theta )\eps $, and $\Theta $ the certified upper bound for the closing quantity of the checkpoint's own criterion. The last column is the section in which the checkpoint is proved: old \S \ of the archived $644$-page manuscript for rows 1--11, master \S \ of the $770$-page manuscript for rows 12--14; rows 15--16 are the Codex improvements and the density-linear baseline integrated here; the verifiers are listed in \cref {tab:cert:checkpoints}}{table.2400}{}} \newlabel{tab:history:checkpoints@cref}{{[table][14][]14}{[1][526][]526}{}{}{}} \newlabel{tab:history:ideas}{{15}{526}{What each checkpoint of \cref {tab:history:checkpoints} added (the new idea in italics), and why it was replaced}{table.lt.15}{}} \newlabel{tab:history:ideas@cref}{{[table][15][]15}{[1][526][]526}{}{}{}} \newlabel{subsec:history:216}{{34.2}{527}{The \texorpdfstring {$216$}{216}-slot starting point}{subsection.2401}{}} \newlabel{subsec:history:216@cref}{{[subsection][2][34]34.2}{[1][527][]527}{}{}{}} \newlabel{tab:history:216}{{16}{528}{The inherited machinery and its place in the present proof. The detailed section-by-section history is preserved in the archived manuscripts}{table.2402}{}} \newlabel{tab:history:216@cref}{{[table][16][]16}{[1][528][]528}{}{}{}} \newlabel{subsec:history:sparse}{{34.3}{528}{Sparse laws, single edges and best cuts}{subsection.2403}{}} \newlabel{subsec:history:sparse@cref}{{[subsection][3][34]34.3}{[1][528][]528}{}{}{}} \newlabel{subsec:history:layers}{{34.4}{528}{Two layers, six queries and the October 18 record}{subsection.2404}{}} \newlabel{subsec:history:layers@cref}{{[subsection][4][34]34.4}{[1][528][]528}{}{}{}} \newlabel{subsec:history:oct24}{{34.5}{528}{Blocks and the \texorpdfstring {$72$}{72}-slot form}{subsection.2405}{}} \newlabel{subsec:history:oct24@cref}{{[subsection][5][34]34.5}{[1][528][]528}{}{}{}} \newlabel{tab:history:components}{{17}{529}{Structural changes retained in the final construction}{table.2406}{}} \newlabel{tab:history:components@cref}{{[table][17][]17}{[1][528][]529}{}{}{}} \newlabel{subsec:history:oct2425}{{34.6}{529}{Exact actual laws, signed blocks and positive roots}{subsection.2407}{}} \newlabel{subsec:history:oct2425@cref}{{[subsection][6][34]34.6}{[1][529][]529}{}{}{}} \newlabel{subsec:history:astra}{{34.7}{529}{The October 29 local refinements}{subsection.2408}{}} \newlabel{subsec:history:astra@cref}{{[subsection][7][34]34.7}{[1][529][]529}{}{}{}} \newlabel{subsec:history:lessons}{{34.8}{530}{What the successive versions showed}{subsection.2409}{}} \newlabel{subsec:history:lessons@cref}{{[subsection][8][34]34.8}{[1][529][]530}{}{}{}} \newlabel{sec:obstructions}{{35}{530}{Obstructions, limits and pitfalls}{section.2410}{}} \newlabel{sec:obstructions@cref}{{[section][35][]35}{[1][530][]530}{}{}{}} \newlabel{subsec:obs:plain}{{35.1}{530}{The crude bound exceeds \texorpdfstring {$1$}{1} (distinct from \texorpdfstring {$\Theta <1$}{Theta<1})}{subsection.2412}{}} \newlabel{subsec:obs:plain@cref}{{[subsection][1][35]35.1}{[1][530][]530}{}{}{}} \newlabel{rem:record:plain}{{35.1}{530}{Why the plain criterion is refined}{remark.2414}{}} \newlabel{rem:record:plain@cref}{{[remark][1][35]35.1}{[1][530][]530}{}{}{}} \newlabel{subsec:obs:reserved}{{35.2}{531}{No positive order at the reserved cut}{subsection.2415}{}} \newlabel{subsec:obs:reserved@cref}{{[subsection][2][35]35.2}{[1][531][]531}{}{}{}} \newlabel{rem:record:variance-n1}{{35.2}{531}{A reserved-cut barrier and its scope}{remark.2417}{}} \newlabel{rem:record:variance-n1@cref}{{[remark][2][35]35.2}{[1][531][]531}{}{}{}} \newlabel{subsec:obs:pairing}{{35.3}{531}{Pairing and signed blocks: norms against envelopes}{subsection.2418}{}} \newlabel{subsec:obs:pairing@cref}{{[subsection][3][35]35.3}{[1][531][]531}{}{}{}} \newlabel{rem:record:pairing-barrier}{{35.3}{532}{Pairing and its barrier}{remark.2420}{}} \newlabel{rem:record:pairing-barrier@cref}{{[remark][3][35]35.3}{[1][532][]532}{}{}{}} \newlabel{rem:obs:pure-sharpness}{{35.4}{532}{The pure paired law at its limits}{remark.2422}{}} \newlabel{rem:obs:pure-sharpness@cref}{{[remark][4][35]35.4}{[1][532][]532}{}{}{}} \newlabel{rem:obs:sign-frontier}{{35.5}{532}{The leading frontier of signed fold laws}{remark.2424}{}} \newlabel{rem:obs:sign-frontier@cref}{{[remark][5][35]35.5}{[1][532][]532}{}{}{}} \newlabel{subsec:obs:prefix}{{35.4}{533}{The walls of the prefix at primes \texorpdfstring {$p\equiv 1\pmod 4$}{p = 1 (mod 4)}}{subsection.2425}{}} \newlabel{subsec:obs:prefix@cref}{{[subsection][4][35]35.4}{[1][533][]533}{}{}{}} \newlabel{rem:record:prefix-walls}{{35.6}{533}{The prefix walls}{remark.2427}{}} \newlabel{rem:record:prefix-walls@cref}{{[remark][6][35]35.6}{[1][533][]533}{}{}{}} \newlabel{subsec:obs:class-one}{{35.5}{533}{Why class one is a prefix}{subsection.2428}{}} \newlabel{subsec:obs:class-one@cref}{{[subsection][5][35]35.5}{[1][533][]533}{}{}{}} \newlabel{subsec:obs:root}{{35.6}{534}{The root law: forced support and forced norm}{subsection.2429}{}} \newlabel{subsec:obs:root@cref}{{[subsection][6][35]35.6}{[1][533][]534}{}{}{}} \newlabel{rem:obs:root-support}{{35.7}{534}{Support closure and the forced norm}{remark.2431}{}} \newlabel{rem:obs:root-support@cref}{{[remark][7][35]35.7}{[1][534][]534}{}{}{}} \newlabel{subsec:obs:twelve}{{35.7}{534}{Why twelve queries do not help}{subsection.2432}{}} \newlabel{subsec:obs:twelve@cref}{{[subsection][7][35]35.7}{[1][534][]534}{}{}{}} \newlabel{rem:obs:twelve}{{35.8}{535}{Two queries force a symmetric error}{remark.2434}{}} \newlabel{rem:obs:twelve@cref}{{[remark][8][35]35.8}{[1][535][]535}{}{}{}} \newlabel{subsec:obs:polynomials}{{35.8}{535}{Obstruction polynomials of the singleton recurrence}{subsection.2435}{}} \newlabel{subsec:obs:polynomials@cref}{{[subsection][8][35]35.8}{[1][535][]535}{}{}{}} \newlabel{lem:obs:rejection-covers}{{35.9}{536}{Rejection-class covers}{lemma.2437}{}} \newlabel{lem:obs:rejection-covers@cref}{{[lemma][9][35]35.9}{[1][536][]536}{}{}{}} \newlabel{tab:obs:polynomials}{{18}{536}{Obstruction polynomials of four coupled sets, $s=x+y+z$ (\cref {lem:obs:rejection-covers}; confirmed by enumerating all sets of rescue types)}{table.2441}{}} \newlabel{tab:obs:polynomials@cref}{{[table][18][]18}{[1][536][]536}{}{}{}} \newlabel{subsec:obs:limits}{{35.9}{537}{Limits of the method}{subsection.2442}{}} \newlabel{subsec:obs:limits@cref}{{[subsection][9][35]35.9}{[1][537][]537}{}{}{}} \newlabel{subsec:obs:tested}{{35.10}{538}{Tested and not pursued}{subsection.2443}{}} \newlabel{subsec:obs:tested@cref}{{[subsection][10][35]35.10}{[1][538][]538}{}{}{}} \newlabel{rem:record:item13}{{35.10}{540}{The three depth-index changes}{remark.2445}{}} \newlabel{rem:record:item13@cref}{{[remark][10][35]35.10}{[1][540][]540}{}{}{}} \newlabel{subsec:obs:pitfalls}{{35.11}{541}{Errors to avoid when checking or extending the proof}{subsection.2447}{}} \newlabel{subsec:obs:pitfalls@cref}{{[subsection][11][35]35.11}{[1][541][]541}{}{}{}} \newlabel{subsec:obs:reviews}{{35.12}{542}{Scope of the reviews}{subsection.2448}{}} \newlabel{subsec:obs:reviews@cref}{{[subsection][12][35]35.12}{[1][542][]542}{}{}{}} \newlabel{app:external}{{A}{544}{External inputs}{appendix.2450}{}} \newlabel{app:external@cref}{{[appendix][1][]A}{[1][544][]544}{}{}{}} \newlabel{subsec:external:gl2}{{A.1}{544}{The characters of \texorpdfstring {$\mathrm {GL}_2(\F _q)$}{GL2(Fq)}}{subsection.2452}{}} \newlabel{subsec:external:gl2@cref}{{[subsection][1][1]A.1}{[1][544][]544}{}{}{}} \newlabel{thm:prelim:gl2}{{A.1}{545}{The characters of $\mathrm {GL}_2(\F _q)$; {\cite [\S 5.2]{FultonHarris}}}{theorem.2454}{}} \newlabel{thm:prelim:gl2@cref}{{[theorem][1][1]A.1}{[1][545][]545}{}{}{}} \newlabel{subsec:external:sheaves}{{A.2}{545}{\texorpdfstring {$\ell $}{l}-adic sheaves on curves}{subsection.2459}{}} \newlabel{subsec:external:sheaves@cref}{{[subsection][2][1]A.2}{[1][545][]545}{}{}{}} \newlabel{it:prelim:E1}{{{{\textup {(E1)}}}}{545}{\texorpdfstring {$\ell $}{l}-adic sheaves on curves}{Item.2460}{}} \newlabel{it:prelim:E1@cref}{{[enumi][1][]{{\textup {(E1)}}}}{[1][545][]545}{}{}{}} \newlabel{it:prelim:E2}{{{{\textup {(E2)}}}}{546}{\texorpdfstring {$\ell $}{l}-adic sheaves on curves}{Item.2461}{}} \newlabel{it:prelim:E2@cref}{{[enumi][2][]{{\textup {(E2)}}}}{[1][546][]546}{}{}{}} \newlabel{it:prelim:E3}{{{{\textup {(E3)}}}}{546}{\texorpdfstring {$\ell $}{l}-adic sheaves on curves}{Item.2462}{}} \newlabel{it:prelim:E3@cref}{{[enumi][3][]{{\textup {(E3)}}}}{[1][546][]546}{}{}{}} \newlabel{it:prelim:E4}{{{{\textup {(E4)}}}}{546}{\texorpdfstring {$\ell $}{l}-adic sheaves on curves}{Item.2463}{}} \newlabel{it:prelim:E4@cref}{{[enumi][4][]{{\textup {(E4)}}}}{[1][546][]546}{}{}{}} \newlabel{thm:prelim:lefschetz}{{A.2}{547}{Grothendieck--Lefschetz trace formula; {\cite [Rapport, Thm.~3.2; Sommes trig., (1.1.1)]{SGA4half}}}{theorem.2465}{}} \newlabel{thm:prelim:lefschetz@cref}{{[theorem][2][1]A.2}{[1][547][]547}{}{}{}} \newlabel{thm:prelim:curves}{{A.3}{547}{Cohomology of open curves; {\cite [(1.4.1)(a), (1.4.1.3), (1.4.2.3)]{DeligneWeilII}}, {\cite [Arcata, IV, Thm.~6.1]{SGA4half}}}{theorem.2467}{}} \newlabel{thm:prelim:curves@cref}{{[theorem][3][1]A.3}{[1][547][]547}{}{}{}} \newlabel{thm:prelim:weights}{{A.4}{547}{Deligne: bounds on weights under $R^if_!$; {\cite [Thm.~3.3.1, Cor.~3.3.4 and (3.3.10)]{DeligneWeilII}}}{theorem.2469}{}} \newlabel{thm:prelim:weights@cref}{{[theorem][4][1]A.4}{[1][547][]547}{}{}{}} \newlabel{thm:prelim:gos}{{A.5}{547}{Grothendieck--Ogg--\v Safarevi\v c formula; {\cite [Thm.~1]{Raynaud}}, {\cite [Exp.~X, \S 7]{SGA5}}}{theorem.2471}{}} \newlabel{thm:prelim:gos@cref}{{[theorem][5][1]A.5}{[1][547][]547}{}{}{}} \newlabel{thm:prelim:ks}{{A.6}{547}{Katz--Sarnak: the family $y^2=h(x)(x-t)$ and its monodromy {\cite [\S 10.1]{KatzSarnak}}}{theorem.2473}{}} \newlabel{thm:prelim:ks@cref}{{[theorem][6][1]A.6}{[1][547][]547}{}{}{}} \newlabel{subsec:external:modular}{{A.3}{548}{A modular coefficient}{subsection.2480}{}} \newlabel{subsec:external:modular@cref}{{[subsection][3][1]A.3}{[1][548][]548}{}{}{}} \newlabel{thm:ahlgren-ono}{{A.7}{548}{Ahlgren--Ono: a character-sum identity via the cusp form $\eta (2z)^4\eta (4z)^4$; Theorems~2 and~6, Lemma~2.2 {\cite {AhlgrenOno2000}}}{theorem.2482}{}} \newlabel{thm:ahlgren-ono@cref}{{[theorem][7][1]A.7}{[1][548][]548}{}{}{}} \newlabel{subsec:external:sources}{{A.4}{549}{Sources of the standard inputs}{subsection.2485}{}} \newlabel{subsec:external:sources@cref}{{[subsection][4][1]A.4}{[1][549][]549}{}{}{}} \newlabel{app:peyre}{{B}{550}{Peyre's tensorization in finite form}{appendix.2487}{}} \newlabel{app:peyre@cref}{{[appendix][2][]B}{[1][550][]550}{}{}{}} \newlabel{sec:peyre:conv}{{B.1}{551}{Conventions}{subsection.2494}{}} \newlabel{sec:peyre:conv@cref}{{[subsection][1][2]B.1}{[1][550][]551}{}{}{}} \newlabel{P:tower}{{{{(P1)}}}{551}{Conventions}{Item.2495}{}} \newlabel{P:tower@cref}{{[enumi][1][]{{(P1)}}}{[1][551][]551}{}{}{}} \newlabel{P:pyth}{{{{(P2)}}}{551}{Conventions}{Item.2496}{}} \newlabel{P:pyth@cref}{{[enumi][2][]{{(P2)}}}{[1][551][]551}{}{}{}} \newlabel{P:restrict}{{{{(P3)}}}{551}{Conventions}{Item.2497}{}} \newlabel{P:restrict@cref}{{[enumi][3][]{{(P3)}}}{[1][551][]551}{}{}{}} \newlabel{lem:peyre:basic}{{B.1}{551}{Projection consequences of maximal correlation}{lemma.2500}{}} \newlabel{lem:peyre:basic@cref}{{[lemma][1][2]B.1}{[1][551][]551}{}{}{}} \newlabel{lem:peyre:one}{{B.2}{552}{One new variable and martingale differences}{lemma.2506}{}} \newlabel{lem:peyre:one@cref}{{[lemma][2][2]B.2}{[1][552][]552}{}{}{}} \newlabel{eq:peyre:one-hyp}{{B.1}{552}{One new variable and martingale differences}{equation.2507}{}} \newlabel{eq:peyre:one-hyp@cref}{{[equation][1][2]B.1}{[1][552][]552}{}{}{}} \newlabel{eq:peyre:one}{{B.2}{552}{One new variable and martingale differences}{equation.2508}{}} \newlabel{eq:peyre:one@cref}{{[equation][2][2]B.2}{[1][552][]552}{}{}{}} \newlabel{eq:peyre:wdiff}{{B.3}{552}{One variable against a list}{equation.2509}{}} \newlabel{eq:peyre:wdiff@cref}{{[equation][3][2]B.3}{[1][552][]552}{}{}{}} \newlabel{lem:peyre:weights}{{B.3}{553}{Positive weights from a Neumann series}{lemma.2512}{}} \newlabel{lem:peyre:weights@cref}{{[lemma][3][2]B.3}{[1][553][]553}{}{}{}} \newlabel{lem:peyre:potential}{{B.4}{553}{A monotone potential for nonnegative losses}{lemma.2514}{}} \newlabel{lem:peyre:potential@cref}{{[lemma][4][2]B.4}{[1][553][]553}{}{}{}} \newlabel{eq:peyre:H}{{B.4}{554}{Proof of the tensorization theorem}{equation.2516}{}} \newlabel{eq:peyre:H@cref}{{[equation][4][2]B.4}{[1][554][]554}{}{}{}} \newlabel{eq:peyre:alpha}{{B.5}{554}{Proof of the tensorization theorem}{equation.2517}{}} \newlabel{eq:peyre:alpha@cref}{{[equation][5][2]B.5}{[1][554][]554}{}{}{}} \newlabel{eq:peyre:goal}{{B.6}{554}{Proof of the tensorization theorem}{equation.2518}{}} \newlabel{eq:peyre:goal@cref}{{[equation][6][2]B.6}{[1][554][]554}{}{}{}} \newlabel{eq:peyre:sum}{{B.7}{554}{Proof of the tensorization theorem}{equation.2519}{}} \newlabel{eq:peyre:sum@cref}{{[equation][7][2]B.7}{[1][554][]554}{}{}{}} \newlabel{eq:peyre:rec}{{B.8}{554}{Proof of the tensorization theorem}{equation.2520}{}} \newlabel{eq:peyre:rec@cref}{{[equation][8][2]B.8}{[1][554][]554}{}{}{}} \newlabel{rem:peyre:source}{{B.5}{555}{Comparison with the source}{remark.2523}{}} \newlabel{rem:peyre:source@cref}{{[remark][5][2]B.5}{[1][555][]555}{}{}{}} \newlabel{rem:peyre:sharp}{{B.6}{555}{Sharpness and the role of conditioning}{remark.2525}{}} \newlabel{rem:peyre:sharp@cref}{{[remark][6][2]B.6}{[1][555][]555}{}{}{}} \newlabel{app:kernel20}{{C}{556}{The actual-square kernel for cutoffs up to \texorpdfstring {$N^{1/20}$}{N to the 1/20}}{appendix.2527}{}} \newlabel{app:kernel20@cref}{{[appendix][3][]C}{[1][556][]556}{}{}{}} \newlabel{lem:kernel-depth-classes}{{C.1}{556}{Root classes at finite conductor depth}{lemma.2532}{}} \newlabel{lem:kernel-depth-classes@cref}{{[lemma][1][3]C.1}{[1][556][]556}{}{}{}} \newlabel{def:record:K20-kernels}{{C.2}{557}{Root weight, unit sieve and the two kernels}{definition.2534}{}} \newlabel{def:record:K20-kernels@cref}{{[definition][2][3]C.2}{[1][557][]557}{}{}{}} \newlabel{eq:record:unitsieve}{{C.1}{557}{Root weight, unit sieve and the two kernels}{equation.2537}{}} \newlabel{eq:record:unitsieve@cref}{{[equation][1][3]C.1}{[1][557][]557}{}{}{}} \newlabel{lem:record:K20-centres}{{C.3}{558}{The model kernel as a sum over centres}{lemma.2541}{}} \newlabel{lem:record:K20-centres@cref}{{[lemma][3][3]C.3}{[1][558][]558}{}{}{}} \newlabel{lem:record:weyl-even}{{C.4}{558}{Weyl's inequality with a linear twist}{lemma.2544}{}} \newlabel{lem:record:weyl-even@cref}{{[lemma][4][3]C.4}{[1][558][]558}{}{}{}} \newlabel{lem:record:arcs}{{C.5}{559}{Arcs}{lemma.2547}{}} \newlabel{lem:record:arcs@cref}{{[lemma][5][3]C.5}{[1][559][]559}{}{}{}} \newlabel{lem:record:prime-power-lift}{{C.6}{560}{Local means at the primes of $D$, and Gauss sums}{lemma.2554}{}} \newlabel{lem:record:prime-power-lift@cref}{{[lemma][6][3]C.6}{[1][560][]560}{}{}{}} \newlabel{lem:record:kernel-coefficient}{{C.7}{561}{The arithmetic coefficient}{lemma.2558}{}} \newlabel{lem:record:kernel-coefficient@cref}{{[lemma][7][3]C.7}{[1][561][]561}{}{}{}} \newlabel{lem:record:K20-approx}{{C.8}{561}{Uniform Fourier approximation}{lemma.2561}{}} \newlabel{lem:record:K20-approx@cref}{{[lemma][8][3]C.8}{[1][561][]561}{}{}{}} \newlabel{lem:record:nonunit-rescale}{{C.9}{562}{Division by an even-valuation square}{lemma.2564}{}} \newlabel{lem:record:nonunit-rescale@cref}{{[lemma][9][3]C.9}{[1][562][]562}{}{}{}} \newlabel{rem:record:K20-range}{{C.10}{563}{The range of the parameters}{remark.2571}{}} \newlabel{rem:record:K20-range@cref}{{[remark][10][3]C.10}{[1][563][]563}{}{}{}} \newlabel{app:certificates}{{D}{563}{Certificates: model, scope, and the evaluation of \texorpdfstring {$\Theta $}{Theta}}{appendix.2573}{}} \newlabel{app:certificates@cref}{{[appendix][4][]D}{[1][563][]563}{}{}{}} \newlabel{subsec:cert:model}{{D.1}{564}{The certificate model and its scope}{subsection.2575}{}} \newlabel{subsec:cert:model@cref}{{[subsection][1][4]D.1}{[1][564][]564}{}{}{}} \newlabel{def:cert:record}{{D.1}{564}{A certificate record}{definition.2577}{}} \newlabel{def:cert:record@cref}{{[definition][1][4]D.1}{[1][564][]564}{}{}{}} \newlabel{subsec:cert:final}{{D.2}{565}{The baseline verifier chain}{subsection.2581}{}} \newlabel{subsec:cert:final@cref}{{[subsection][2][4]D.2}{[1][565][]565}{}{}{}} \gdef \LT@vi {\LT@entry {1}{102.13388pt}\LT@entry {1}{171.88747pt}\LT@entry {1}{185.38547pt}} \newlabel{tab:cert:finite}{{19}{567}{The finite inequalities used in Parts~II--V, in the order of the construction, with their checkers}{table.lt.19}{}} \newlabel{tab:cert:finite@cref}{{[table][19][]19}{[1][567][]567}{}{}{}} \newlabel{cert:record:analytic-stage}{{D.2}{572}{The analytic stage}{certificate.2591}{}} \newlabel{cert:record:analytic-stage@cref}{{[certificate][2][4]D.2}{[1][572][]572}{}{}{}} \newlabel{cert:record:frame-data}{{D.3}{573}{Data of the six-query frame}{certificate.2601}{}} \newlabel{cert:record:frame-data@cref}{{[certificate][3][4]D.3}{[1][573][]573}{}{}{}} \newlabel{cert:record:middle-price}{{D.4}{573}{Middle prices}{certificate.2609}{}} \newlabel{cert:record:middle-price@cref}{{[certificate][4][4]D.4}{[1][573][]573}{}{}{}} \newlabel{cert:record:one-stage}{{D.5}{574}{The one-stage coefficients}{certificate.2617}{}} \newlabel{cert:record:one-stage@cref}{{[certificate][5][4]D.5}{[1][574][]574}{}{}{}} \newlabel{cert:record:old-f-cap}{{D.6}{574}{The negative caps of the reference fold record}{certificate.2619}{}} \newlabel{cert:record:old-f-cap@cref}{{[certificate][6][4]D.6}{[1][574][]574}{}{}{}} \newlabel{cert:record:e-coefficients}{{D.7}{575}{The matching coefficients}{certificate.2621}{}} \newlabel{cert:record:e-coefficients@cref}{{[certificate][7][4]D.7}{[1][574][]575}{}{}{}} \newlabel{cert:record:weighted-identity}{{D.8}{575}{The weighted second-moment identity}{certificate.2623}{}} \newlabel{cert:record:weighted-identity@cref}{{[certificate][8][4]D.8}{[1][575][]575}{}{}{}} \newlabel{cert:record:variance-linear}{{D.9}{575}{The piece data of the root}{certificate.2625}{}} \newlabel{cert:record:variance-linear@cref}{{[certificate][9][4]D.9}{[1][575][]575}{}{}{}} \newlabel{cert:record:matching}{{D.10}{575}{The sides of the matching envelopes}{certificate.2627}{}} \newlabel{cert:record:matching@cref}{{[certificate][10][4]D.10}{[1][575][]575}{}{}{}} \newlabel{cert:record:means}{{D.11}{576}{Positive mean savings}{certificate.2629}{}} \newlabel{cert:record:means@cref}{{[certificate][11][4]D.11}{[1][576][]576}{}{}{}} \newlabel{subsec:cert:astra}{{D.3}{576}{Checks for the local refinements of 29 October}{subsection.2630}{}} \newlabel{subsec:cert:astra@cref}{{[subsection][3][4]D.3}{[1][576][]576}{}{}{}} \newlabel{cert:astra-local}{{D.12}{576}{Local identities and the joint-row witness}{certificate.2632}{}} \newlabel{cert:astra-local@cref}{{[certificate][12][4]D.12}{[1][576][]576}{}{}{}} \newlabel{subsec:cert:evaluation}{{D.4}{577}{How the certificate evaluates \texorpdfstring {$\Theta $}{Theta}}{subsection.2637}{}} \newlabel{subsec:cert:evaluation@cref}{{[subsection][4][4]D.4}{[1][577][]577}{}{}{}} \newlabel{tab:cert:evaluation-files}{{20}{577}{The inputs of the selected evaluation (S denotes \texttt {research/push\_2026\_10\_25/}; the other prefixes are as in \cref {tab:cert:finite}). SHA-256 hashes are abbreviated to their first and last eight hexadecimal digits; the full hashes are pinned by the design and final record}{table.2638}{}} \newlabel{tab:cert:evaluation-files@cref}{{[table][20][]20}{[1][577][]577}{}{}{}} \newlabel{subsec:cert:inherited}{{D.5}{579}{What the earlier verifiers contribute}{subsection.2649}{}} \newlabel{subsec:cert:inherited@cref}{{[subsection][5][4]D.5}{[1][579][]579}{}{}{}} \newlabel{rem:cert:deligne-tests}{{D.13}{579}{Consistency tests of the second-order bounds}{remark.2652}{}} \newlabel{rem:cert:deligne-tests@cref}{{[remark][13][4]D.13}{[1][579][]579}{}{}{}} \newlabel{tab:cert:inherited}{{21}{580}{The earlier verifiers of the chain and what the final proof takes from them (prefixes of the check names omitted)}{table.2650}{}} \newlabel{tab:cert:inherited@cref}{{[table][21][]21}{[1][579][]580}{}{}{}} \newlabel{subsec:cert:archive}{{D.6}{580}{The archive and the earlier checkpoints}{subsection.2653}{}} \newlabel{subsec:cert:archive@cref}{{[subsection][6][4]D.6}{[1][580][]580}{}{}{}} \newlabel{tab:cert:checkpoints}{{22}{582}{The checkpoints of \cref {tab:history:checkpoints} and their entry points (from the repository root; the exponents are $\eps $ of the corresponding theorem). The last eight rows are the checkpoints whose verifiers (seven in all, the \texttt {research/push\_2026\_10\_24/} verifier serving two of the rows) are run by \texttt {paper/verify.py} (\cref {subsec:cert:final}); the first five of the seven formed the chain at commit \texttt {8dc0a3fe}}{table.2654}{}} \newlabel{tab:cert:checkpoints@cref}{{[table][22][]22}{[1][582][]582}{}{}{}} \newlabel{rem:cert:provenance}{{D.14}{582}{Provenance}{remark.2656}{}} \newlabel{rem:cert:provenance@cref}{{[remark][14][4]D.14}{[1][582][]582}{}{}{}} \newlabel{app:data}{{E}{583}{Design data, prices and witness tables}{appendix.2658}{}} \newlabel{app:data@cref}{{[appendix][5][]E}{[1][583][]583}{}{}{}} \gdef \LT@vii {\LT@entry {1}{59.50104pt}\LT@entry {1}{397.15125pt}} \newlabel{subsec:data:parameters}{{E.1}{584}{The parameters}{subsection.2661}{}} \newlabel{subsec:data:parameters@cref}{{[subsection][1][5]E.1}{[1][584][]584}{}{}{}} \newlabel{tab:data:parameters}{{23}{584}{The parameters of the construction}{table.lt.23}{}} \newlabel{tab:data:parameters@cref}{{[table][23][]23}{[1][584][]584}{}{}{}} \newlabel{subsec:data:pieces}{{E.2}{584}{The middle pieces}{subsection.2662}{}} \newlabel{subsec:data:pieces@cref}{{[subsection][2][5]E.2}{[1][584][]584}{}{}{}} \gdef \LT@viii {\LT@entry {4}{12.50002pt}\LT@entry {4}{46.25002pt}\LT@entry {4}{46.25002pt}\LT@entry {4}{37.75002pt}\LT@entry {1}{23.63133pt}\LT@entry {4}{29.25002pt}\LT@entry {4}{51.94452pt}\LT@entry {4}{55.61118pt}\LT@entry {4}{51.61118pt}} \gdef \LT@ix {\LT@entry {4}{14.5556pt}\LT@entry {4}{69.86116pt}\LT@entry {4}{57.11116pt}\LT@entry {4}{90.19452pt}\LT@entry {4}{61.61116pt}} \newlabel{tab:record:middle-pieces}{{24}{585}{Middle pieces: exact blocks, cells, the range of the cell integers $n_j$, and the degree-$d$ charges $\bar I_{d,i}$ at $a_0$ (upper endpoints, rounded up). Source: \texttt {refined\_L570\_source.json} (\texttt {middle.pieces[i].degree\_charges}) and \texttt {refined\_L570\_charges.json} (\texttt {bands[i]}: \texttt {finite\_parts}, \texttt {analytic})}{table.lt.24}{}} \newlabel{tab:record:middle-pieces@cref}{{[table][24][]24}{[1][584][]585}{}{}{}} \newlabel{tab:record:middle-charges}{{25}{585}{The four first-stage sums of each piece at $a_0$ (upper endpoints, rounded up); the totals are the enclosures of the sums, not the sums of the displayed values. Source: \texttt {refined\_L570\_charges.json} (\texttt {bands[i].charges}, \texttt {sums})}{table.lt.25}{}} \newlabel{tab:record:middle-charges@cref}{{[table][25][]25}{[1][585][]585}{}{}{}} \gdef \LT@x {\LT@entry {4}{11.50002pt}\LT@entry {4}{63.61116pt}\LT@entry {4}{67.86116pt}\LT@entry {4}{50.86116pt}\LT@entry {4}{63.61116pt}\LT@entry {4}{67.86116pt}\LT@entry {4}{67.86116pt}\LT@entry {4}{64.86116pt}} \gdef \LT@xi {\LT@entry {4}{11.50002pt}\LT@entry {4}{14.50002pt}\LT@entry {4}{54.19452pt}\LT@entry {4}{60.58345pt}\LT@entry {4}{53.61118pt}\LT@entry {4}{54.19452pt}\LT@entry {4}{49.94452pt}\LT@entry {4}{53.61118pt}\LT@entry {4}{58.44452pt}\LT@entry {4}{30.86116pt}} \newlabel{tab:data:middle-weights}{{26}{587}{Completion weights of the middle pieces; exact decimals, except $w_{\rm C}$ (a rational with a long denominator, rounded up). Source: \texttt {refined\_L570\_source.json} (\texttt {middle.pieces[i].local.weights})}{table.lt.26}{}} \newlabel{tab:data:middle-weights@cref}{{[table][26][]26}{[1][586][]587}{}{}{}} \newlabel{tab:data:piece-values}{{27}{587}{Piece values: upper bounds, rounded up, except the lower bounds $\Sigma _i$, rounded down. Sources: the read-only evaluation of \texttt {piece\_data\_beta.compute} (modular root variant) on the native source (\texttt {count}, \texttt {h}, \texttt {M}, \texttt {chi}, \texttt {kf}, \texttt {eps}, \texttt {H}, \texttt {starts}); on the pieces $27$--$33$ the root plan \texttt {further\_root\_construction.changes} for $M_i$, $\chi _i$; \texttt {author.json} (\texttt {restoration\_product\_caps.rows[i].log\_cap}) for $L_i$}{table.lt.27}{}} \newlabel{tab:data:piece-values@cref}{{[table][27][]27}{[1][587][]587}{}{}{}} \gdef \LT@xii {\LT@entry {4}{18.83333pt}\LT@entry {4}{69.61116pt}\LT@entry {4}{69.61116pt}\LT@entry {4}{69.61116pt}\LT@entry {4}{69.61116pt}\LT@entry {4}{63.61116pt}} \newlabel{tab:data:cut-caps}{{28}{588}{The block caps of the reference at the piece starts, $L_{\rm loc}=585$ (upper bounds, rounded up). Source: \texttt {refined\_L570\_source.json} (\texttt {middle.pieces[i].local.spectra}: \texttt {L20}, \texttt {L21}, \texttt {F21}, \texttt {E21}, \texttt {L10}, field \texttt {block\_d}; the flags \texttt {further\_positive\_pair\_square} of L20 on every piece, \texttt {further\_positive\_pair\_square} of L20 and L21 on the pieces $27$--$33$, \texttt {advance\_old\_negative} of F21)}{table.lt.28}{}} \newlabel{tab:data:cut-caps@cref}{{[table][28][]28}{[1][588][]588}{}{}{}} \gdef \LT@xiii {\LT@entry {4}{15.5556pt}\LT@entry {4}{46.36116pt}\LT@entry {4}{42.11116pt}\LT@entry {4}{42.11116pt}\LT@entry {4}{70.94452pt}\LT@entry {4}{58.19452pt}\LT@entry {4}{58.19452pt}\LT@entry {4}{53.19452pt}} \newlabel{subsec:data:prices}{{E.3}{589}{Middle prices}{subsection.2666}{}} \newlabel{subsec:data:prices@cref}{{[subsection][3][5]E.3}{[1][589][]589}{}{}{}} \newlabel{tab:data:prices}{{29}{589}{Middle prices at $a_0$, part~I: the coefficients of the signed fold records at $X_i$ and their prices (upper bounds, rounded up); $A^{\rm arm}_{F,i}=A^{\rm arm}_{E,i}$; part~II is the next table. Source: the read-only evaluation of \texttt {low\_domain.raw\_ledgers} at $\tlaw =127/500$ on the native source (\texttt {rows[i].prices}: \texttt {BF}, \texttt {LF}, \texttt {RF}, \texttt {SF}; \texttt {rows[i].bounds})}{table.lt.29}{}} \newlabel{tab:data:prices@cref}{{[table][29][]29}{[1][589][]589}{}{}{}} \gdef \LT@xiv {\LT@entry {4}{13.9556pt}\LT@entry {4}{54.9945pt}\LT@entry {4}{34.66115pt}\LT@entry {4}{67.7445pt}\LT@entry {4}{67.7445pt}\LT@entry {4}{58.66116pt}\LT@entry {4}{54.9945pt}\LT@entry {4}{54.9945pt}\LT@entry {4}{51.59451pt}} \gdef \LT@xv {\LT@entry {4}{11.50002pt}\LT@entry {1}{20.83363pt}\LT@entry {4}{57.86118pt}\LT@entry {1}{46.61069pt}\LT@entry {4}{42.36116pt}\LT@entry {4}{42.36116pt}\LT@entry {4}{42.36116pt}\LT@entry {4}{42.36116pt}\LT@entry {4}{38.11116pt}\LT@entry {4}{35.11116pt}} \newlabel{subsec:data:aux}{{E.4}{591}{The sides of the matching envelopes}{subsection.2667}{}} \newlabel{subsec:data:aux@cref}{{[subsection][4][5]E.4}{[1][591][]591}{}{}{}} \newlabel{tab:data:sides}{{31}{591}{The sides of the matching envelopes at the piece starts (upper bounds, rounded up). Sources: the read-only evaluation of \texttt {low\_domain.raw\_ledgers} (\texttt {rows[i].matching}: \texttt {count}, \texttt {density}, \texttt {absolute\_new\_coefficient}, \texttt {old\_left}, \texttt {old\_right}, \texttt {left}, \texttt {right}) and the weights of \cref {tab:data:middle-weights}}{table.lt.31}{}} \newlabel{tab:data:sides@cref}{{[table][31][]31}{[1][591][]591}{}{}{}} \gdef \LT@xvi {\LT@entry {4}{43.1952pt}\LT@entry {1}{29.77002pt}\LT@entry {4}{37.75002pt}\LT@entry {1}{19.08885pt}\LT@entry {4}{48.61116pt}\LT@entry {4}{48.61116pt}\LT@entry {4}{68.94452pt}\LT@entry {4}{64.94452pt}} \newlabel{subsec:data:upper}{{E.5}{592}{The upper bands}{subsection.2668}{}} \newlabel{subsec:data:upper@cref}{{[subsection][5][5]E.5}{[1][592][]592}{}{}{}} \newlabel{tab:data:upper-bands}{{32}{592}{The upper bands: root entries at the first band of each group (upper bounds, rounded up; integers exact) and the group's part of $S$ and $A$ at $a_{\rm u}$ (upper bounds of the exact sums, rounded up). Source: \texttt {upper\_dense\_refined.json} (\texttt {rows[*]}: \texttt {local\_budget}, \texttt {inputs.L.d}, \texttt {reserved\_caps.LL}, \texttt {six\_query\_LE\_mixture}, \texttt {S}, \texttt {A}; \texttt {tail\_S}, \texttt {tail\_A}); tail datum: \texttt {upper\_v2\_local.json}}{table.lt.32}{}} \newlabel{tab:data:upper-bands@cref}{{[table][32][]32}{[1][592][]592}{}{}{}} \newlabel{subsec:data:envelopes}{{E.6}{594}{Envelope witnesses}{subsection.2669}{}} \newlabel{subsec:data:envelopes@cref}{{[subsection][6][5]E.6}{[1][594][]594}{}{}{}} \gdef \LT@xvii {\LT@entry {4}{33.83539pt}\LT@entry {4}{46.94122pt}\LT@entry {4}{46.96844pt}\LT@entry {4}{50.86116pt}\LT@entry {4}{50.86116pt}\LT@entry {4}{46.61116pt}\LT@entry {4}{42.36116pt}\LT@entry {4}{54.19452pt}\LT@entry {4}{63.94452pt}} \newlabel{tab:data:envelopes}{{33}{595}{The envelopes of the sixteen classes: caps and masses (upper bounds, rounded up, except $M^{\rm inv}$, a lower bound rounded down), the leading coupon (upper bound) and the saving $D_{n,m}$ at the exponent $a$ (lower bound, rounded down). Sources: \texttt {exact\_background\_pairs.json} ($\kappa _H$, $\kappa _b$, $M$); \texttt {author.json} (\texttt {invariant\_error.orbit\_masses}, \texttt {invariant\_error.leading\_coupons}, \texttt {discounts})}{table.lt.33}{}} \newlabel{tab:data:envelopes@cref}{{[table][33][]33}{[1][595][]595}{}{}{}} \newlabel{subsec:data:grids}{{E.7}{595}{Spectral grids and analytic slacks}{subsection.2673}{}} \newlabel{subsec:data:grids@cref}{{[subsection][7][5]E.7}{[1][595][]595}{}{}{}} \gdef \LT@xviii {\LT@entry {4}{41.25002pt}\LT@entry {4}{29.61116pt}\LT@entry {4}{18.75002pt}\LT@entry {4}{29.61116pt}\LT@entry {4}{49.36118pt}\LT@entry {4}{29.61116pt}\LT@entry {4}{49.36118pt}\LT@entry {4}{38.11116pt}\LT@entry {4}{49.36118pt}\LT@entry {4}{29.61116pt}\LT@entry {4}{46.36118pt}} \newlabel{tab:data:layer12-grid}{{34}{596}{The twelve-label grids: $g_P$ and $c^+_P$ for the five cuts (upper bounds, rounded up). Sources: \texttt {middle12\_grid.json} and \texttt {middle\_grid\_new.json} (\texttt {points[*].cuts}: the class-three \texttt {tests[*].g}, \texttt {positive\_B})}{table.lt.34}{}} \newlabel{tab:data:layer12-grid@cref}{{[table][34][]34}{[1][596][]596}{}{}{}} \gdef \LT@xix {\LT@entry {4}{41.33333pt}\LT@entry {4}{63.61116pt}\LT@entry {4}{47.36116pt}\LT@entry {4}{41.25002pt}\LT@entry {4}{63.61116pt}\LT@entry {4}{47.36116pt}\LT@entry {4}{41.25002pt}\LT@entry {4}{63.61116pt}\LT@entry {4}{39.36116pt}} \gdef \LT@xx {\LT@entry {4}{86.21466pt}\LT@entry {4}{85.94452pt}\LT@entry {4}{85.94452pt}\LT@entry {4}{85.94452pt}\LT@entry {4}{81.94452pt}} \gdef \LT@xxi {\LT@entry {4}{86.21466pt}\LT@entry {4}{89.61118pt}\LT@entry {4}{89.61118pt}\LT@entry {4}{85.61118pt}} \newlabel{tab:data:l20-grid}{{35}{597}{The L20 grid of the uniform root: $g_{20}(P)$ (exact recorded value) and $c^+_{20}(P)$ (upper bound, rounded up). Source: \texttt {l20\_refined\_Q\_grid.json} (\texttt {rows[*]}: \texttt {p0}, \texttt {clean\_g}, \texttt {positive\_B})}{table.lt.35}{}} \newlabel{tab:data:l20-grid@cref}{{[table][35][]35}{[1][596][]597}{}{}{}} \newlabel{tab:data:positive-roots}{{36}{597}{The seven selected positive roots (exact recorded rationals, or upper bounds rounded up). Sources: \texttt {refined\_L570\_source.json}, field \texttt {further\_root\_construction.changes}, and its native spectra. Pair-square parameters use physical pair interpolation and the resummed L21 cap; the coherent law uses the finite $39$-term chamber and layer bounds with single-pin refinement}{table.lt.36}{}} \newlabel{tab:data:positive-roots@cref}{{[table][36][]36}{[1][597][]597}{}{}{}} \newlabel{tab:data:positive-roots-late}{{37}{597}{The remaining selected root laws; notation and sources as in \cref {tab:data:positive-roots}}{table.lt.37}{}} \newlabel{tab:data:positive-roots-late@cref}{{[table][37][]37}{[1][597][]597}{}{}{}} \gdef \LT@xxii {\LT@entry {4}{40.36188pt}\LT@entry {4}{211.18214pt}\LT@entry {4}{181.3479pt}} \newlabel{tab:data:slacks}{{38}{598}{Analytic slacks: exact rationals (decimals rounded down); the tail coefficients and gates are upper bounds, independent of $a$. Sources: \texttt {refined\_L570\_source.json} (\texttt {analytic}: \texttt {inherited\_transfer\_slacks}, \texttt {inherited\_kernel\_slacks}, \texttt {tail\_gate\_values}; \texttt {upper.tail\_mixing}) and \texttt {analytic\_domain.json}}{table.lt.38}{}} \newlabel{tab:data:slacks@cref}{{[table][38][]38}{[1][598][]598}{}{}{}} \newlabel{app:openai-constant}{{F}{599}{The exponent from the OpenAI parameters as displayed}{appendix.2680}{}} \newlabel{app:openai-constant@cref}{{[appendix][6][]F}{[1][599][]599}{}{}{}} \newlabel{eq:oa:symbolic}{{F.1}{599}{Result}{equation.2683}{}} \newlabel{eq:oa:symbolic@cref}{{[equation][1][6]F.1}{[1][599][]599}{}{}{}} \newlabel{eq:oa:tower}{{F.2}{599}{Result}{equation.2684}{}} \newlabel{eq:oa:tower@cref}{{[equation][2][6]F.2}{[1][599][]599}{}{}{}} \newlabel{eq:oa:e0}{{F.3}{599}{Result}{equation.2685}{}} \newlabel{eq:oa:e0@cref}{{[equation][3][6]F.3}{[1][599][]599}{}{}{}} \newlabel{eq:oa:decimal}{{F.4}{599}{Result}{equation.2686}{}} \newlabel{eq:oa:decimal@cref}{{[equation][4][6]F.4}{[1][599][]599}{}{}{}} \newlabel{subsec:oa:fixed}{{F.1}{600}{The fixed construction}{subsection.2687}{}} \newlabel{subsec:oa:fixed@cref}{{[subsection][1][6]F.1}{[1][600][]600}{}{}{}} \newlabel{subsec:oa:P}{{F.2}{600}{The prime threshold \texorpdfstring {$P$}{P}}{subsection.2688}{}} \newlabel{subsec:oa:P@cref}{{[subsection][2][6]F.2}{[1][600][]600}{}{}{}} \newlabel{eq:oa:clead}{{F.5}{600}{The prime threshold \texorpdfstring {$P$}{P}}{equation.2689}{}} \newlabel{eq:oa:clead@cref}{{[equation][5][6]F.5}{[1][600][]600}{}{}{}} \newlabel{eq:oa:logP}{{F.6}{600}{The prime threshold \texorpdfstring {$P$}{P}}{equation.2690}{}} \newlabel{eq:oa:logP@cref}{{[equation][6][6]F.6}{[1][600][]600}{}{}{}} \newlabel{subsec:oa:exponent}{{F.3}{600}{Small modulus, good residues, and the exponent}{subsection.2691}{}} \newlabel{subsec:oa:exponent@cref}{{[subsection][3][6]F.3}{[1][600][]600}{}{}{}} \bibcite{AhlgrenOno2000}{1} \bibcite{AhlswedeGacs76}{2} \bibcite{BeigelGasarch}{3} \bibcite{BMOR18}{4} \bibcite{BerndtEvansWilliams}{5} \bibcite{BloomMaynard}{6} \bibcite{BorgsChayesLovaszSosVesztergombi08}{7} \bibcite{Bourgain99}{8} \bibcite{ConlonLee}{9} \bibcite{Davenport00}{10} \bibcite{dlPMS}{11} \bibcite{SGA4half}{12} \bibcite{DeligneWeilII}{13} \bibcite{DeligneWeilI}{14} \bibcite{DysonLiebSimon78}{15} \bibcite{FKMPrimes14}{16} \bibcite{FKMTwists15}{17} \bibcite{FKMSBilinearTrace25}{18} \bibcite{FILS}{19} \bibcite{FrohlichLieb}{20} \bibcite{FrohlichSimonSpencer76}{21} \bibcite{FultonHarris}{22} \bibcite{Furstenberg77}{23} \bibcite{GlimmJaffe87}{24} \bibcite{Gowers01}{25} \bibcite{GreenSawhney}{26} \bibcite{SGA1}{27} \bibcite{SGA5}{28} \bibcite{HatamiNorine11}{29} \bibcite{Hirschfeld35}{30} \bibcite{IrelandRosen}{31} \bibcite{Isaacs76}{32} \bibcite{IwaniecKowalski}{33} \bibcite{Kassabov}{34} \bibcite{KatzGKM}{35} \bibcite{KatzSarnak}{36} \bibcite{KatzESDE90}{37} \bibcite{KatzTLM02}{38} \bibcite{KatzMMP05}{39} \bibcite{KowalskiBourbakiSawinShusterman}{40} \bibcite{KMS17}{41} \bibcite{KMS20}{42} \bibcite{Krachun}{43} \bibcite{Lewko15}{44} \bibcite{LovaszGraphLimits12}{45} \bibcite{MontgomeryVaughan}{46} \bibcite{MooreKearfottCloud09}{47} \bibcite{NaslundUpperRepository2026}{48} \bibcite{NaslundPalomar2026}{49} \bibcite{NaslundHexagon2026}{50} \bibcite{Neumaier90}{51} \bibcite{OpenAI}{52} \bibcite{PartI}{53} \bibcite{Peyre}{54} \bibcite{PiatetskiShapiro83}{55} \bibcite{PSS88}{56} \bibcite{PlattTrudgian21}{57} \bibcite{Raynaud}{58} \bibcite{Razborov07}{59} \bibcite{Renyi59}{60} \bibcite{RosserSchoenfeld75}{61} \bibcite{Roth53}{62} \bibcite{Ruzsa84}{63} \bibcite{Sanders11}{64} \bibcite{Sarkozy78}{65} \bibcite{SawinFactorization24}{66} \bibcite{SawinQST23}{67} \bibcite{SawinShusterman22}{68} \bibcite{Schmidt76}{69} \bibcite{Serre77}{70} \bibcite{TaoVu06}{71} \bibcite{Vaughan97}{72} \bibcite{Weil48}{73} \bibcite{Weil49}{74} \expandafter\gdef\csname r@tocindent-1\endcsname{0pt} \expandafter\gdef\csname r@tocindent0\endcsname{64.17908pt} \expandafter\gdef\csname r@tocindent1\endcsname{72.54378pt} \expandafter\gdef\csname r@tocindent2\endcsname{44.77336pt} \expandafter\gdef\csname r@tocindent3\endcsname{0pt} }{}% }{}% \immediate\write\@auxout{\string\gdef\string\HexagonAuxReady{}}% } \makeatother \begin{document} \begin{NoHyper} \emergencystretch=3em \begin{abstract} Let $A\subseteq\{1,\ldots,N\}$ contain no two distinct elements whose difference is a nonzero square, and let $s(N)$ be the largest possible size of such a set. We prove \[ s(N)\le CN^{0.9999873} \] with an absolute constant $C$. A recent preprint of OpenAI proves $s(N)\le CN^{1-\eps}$ for some absolute $\eps>0$. Their proof utilizes a certain average of the Fourier transform over $(24!)^{161}$ points, and for the parameter choices displayed there we calculate that they obtained (\cref{app:openai-constant}) $\eps\approx \exp_{10}(-\exp_{10}(\exp_{10}(5782.77)))$, in the sense that $\log_{10}\log_{10}\log_{10}(1/\eps)\approx5782.77$. We follow the same overall strategy, with new work at almost every quantitative step. The largest gain is the use of $72$ slots (positions at which the Fourier transform is evaluated) in place of $(24!)^{161}$: the exponent is roughly a fixed constant divided by the number of slots, so this alone gains many orders of magnitude, but leaves far less room for loss elsewhere. Other savings come from the local construction at each prime. Small primes are handled jointly rather than one by one; and errors are measured in the actual half-distributions of the laws being compared, not bounded term by term against a product model. Where sums over the primes of a block of Weil-type error terms of size $O(p^{-1/2})$ would be too weak, we prove bounds of order $O(p^{-1})$ for the same error terms using \'etale cohomology over finite fields (Deligne's theorems and Katz--Sarnak monodromy for families of curves), the representation theory of $\mathrm{GL}_2(\mathbf F_p)$, exact counts at $p\equiv3\pmod4$, and a modular evaluation of Ahlgren and Ono. Dependence in our distributions is controlled by the correlation inequalities of Peyre and Kassabov. The remaining finitely many numerical inequalities are verified by exact computer arithmetic, listed in the appendices; all analytic steps are proved in the text. The companion repository \cite{NaslundUpperRepository2026} contains a partial Lean 4 formalization, totaling over 600,000 lines of lean. It establishes $s(N)\le C N^{0.99999}$, conditional on five named analytic inputs and explicit numerical hypotheses. This formalizes the most critical parts of the proof. \end{abstract} \maketitle \begin{center} \fcolorbox{gray!60}{ourcolumn}{% \begin{minipage}{\dimexpr1\linewidth-3\fboxsep-3\fboxrule\relax} \small\setlength{\parindent}{0pt}\vspace{3pt}% \textsuperscript{$*$}\textbf{AI use:} This paper was written by Claude Opus 5.5, GPT Astra 6, and Muse Wonder-Full 1.0, under my prompting and supervision. The research was carried out by Claude Opus 5.5, GPT Astra 6, and ChatGPT Pro queries. I tried to have the AIs write a readable and comprehensible introduction that details the differences between this work and OpenAI's work, and the new ideas involved. This includes a dependency diagram showing the structure of the overall proof. In earlier drafts I found the introduction to be incomprehensible, and it was re-written under my supervision multiple times, so I hope these updates (primarily from Muse and Codex) help the reader get a sense of the overall work. I also recommend that the reader utilize their AI assistant of choice to help understand the paper. The proof has undergone several intensive adversarial reviews by GPT Astra 6 and other agents; no errors or gaps were found in those reviews. A Lean 4 formalization totaling over 600,000 lines of lean appears in the companion repository \cite{NaslundUpperRepository2026}. This formalization establishes $s(N)\le C N^{0.99999}$, conditional on five named analytic inputs and explicit numerical hypotheses. This lean code was generated by Claude Opus 5.5 and GPT Astra 6, and covers many of the most critical parts of the proof. The scope of the finite computer checks and internal reviews is stated in \cref{subsec:intro:status}, \cref{app:certificates} and \cref{subsec:obs:reviews}.\vspace{2pt} \end{minipage}} \end{center} \clearpage \setcounter{tocdepth}{2} \tableofcontents \clearpage % Begin sections/01_introduction \providecommand{\PushA}{\frac{5422587}{6103515625}} \providecommand{\PushExponent}{\frac{5422587}{433349609375}} \providecommand{\PushDecimal}{1.25131923109859\ldots\cdot10^{-5}} \providecommand{\PushK}{890666} \providecommand{\PushTheta}{0.99999999997327} \section{Introduction}\label{sec:intro} \subsection{Statement and Context}\label{subsec:intro:statement} We say that a set $A\subseteq[N]$, where $[N]=\{1,\ldots,N\}$, is \emph{square-difference-free} if no difference of two distinct elements of $A$ is the square of a positive integer. Let $s(N)$ be the largest possible size of such a set. Furstenberg \cite{Furstenberg77} and S\'ark\"ozy \cite{Sarkozy78} proved that $s(N)=o(N)$. The quantitative bounds were subsequently improved by Pintz--Steiger--Szemer\'edi \cite{PSS88} and Bloom--Maynard \cite{BloomMaynard}. Green and Sawhney \cite{GreenSawhney} then showed that $s(N)\ll N\exp(-c_0\sqrt{\log N})$ for an absolute $c_0>0$, which saves more than every fixed power of $\log N$ but less than a fixed power of $N$. OpenAI \cite{OpenAI} then gave the first power saving, proving that for some absolute $\eps>0$ we have $s(N)\le CN^{1-\eps}$. For the parameter choices displayed in OpenAI's paper, we calculate (\cref{app:openai-constant}) \[ \eps\approx10^{-10^{10^{5782.77}}},\qquad\text{in the sense that}\qquad \log_{10}\log_{10}\log_{10}(1/\eps)\approx5782.77. \] This quantifies that one choice of parameters; it is not a claim about the best exponent their method could give. This paper works within the OpenAI framework, and makes $\eps$ explicit, with new quantitative work at almost every step. \begin{theorem}\label{thm:main} For every integer $N\ge1$ and every square-difference-free set $A\subseteq[N]$, \[ |A|\le CN^{1-\eps},\qquad \eps=\FourRoutesExponent, \] so that the exponent is $1-\eps=0.999987\ldots$, where $C$ is an absolute constant. \end{theorem} Here $\eps=a/(72-\vartheta)$ with $a=\FourRoutesA$ and $\vartheta=\FourRoutesDensity$. The exponent $1-\eps$ is still far from the exponents in the known constructions of large square-difference-free sets. Ruzsa's construction \cite{Ruzsa84}, improved in \cite{BeigelGasarch,Lewko15}, gives exponents near $0.7334$, and Krachun \cite{Krachun} gave an exponent exceeding $3/4$. The strongest lower-bound construction is Naslund's, with exponent $0.7580758$ \cite{NaslundHexagon2026}; its finite certificates are formalized in Lean \cite{NaslundPalomar2026}. The shape of the argument is as follows: let $\alpha=|A|/N$ be the density and let $Y$ be the $72$-point Fourier average defined in \cref{subsec:intro:method} below. The proof shows $\alpha^{72}\le Y$ (by reflection positivity) and $Y\le C\Lsc^{-a}\alpha^{\vartheta}$, where $\Lsc=N/\Kint$ is the length of each of the $\Kint$ subintervals of $[N]$ (Step~1 below). Hence $\alpha^{72-\vartheta}\ll\Lsc^{-a}$, which is the power saving. Here $a$ measures decay with scale and $\vartheta$ is the power of $\alpha$ in the upper bound; for $0<\alpha<1$ a larger $\vartheta$ gives a smaller upper bound at fixed $a$. The word \emph{slot} means one of the $72$ positions at which the Fourier series is evaluated; a \emph{law} is a probability or signed distribution on assignments of group elements to the slots. Full definitions are in \cref{sec:mechanism} (informally) and Parts~II--III (formally), and \cref{subsec:intro:glossary} collects the terminology in one place. The paper proves the upper bound in two stages that share the same notation and must not be confused. The \emph{baseline} stage, through \cref{sec:closing}, works with $\vartheta=1$ and proves the proposition below. The \emph{improved} stage, \crefrange{sec:density:moments-prefix}{sec:four-routes-closing}, then strengthens the density estimate to $\vartheta=\FourRoutesDensity>1$, recomputes the prices (defined in \cref{subsec:intro:method}) at the new parameters, and proves \cref{thm:main}. Numerical tables before the improved stage belong to the baseline unless the caption says otherwise. \begin{proposition}[The baseline bound, with density exponent $\vartheta=1$]\label{thm:baseline} For an absolute constant $C_0$, $s(N)\le C_0N^{1-\PushExponent}$. This uses $a=\PushA$, $\vartheta=1$ and $K=\PushK$ intervals (the number $\Kint$ of intervals in Step~1 below). \end{proposition} \Cref{subsec:proof-main} proves this baseline. The improved stage then reproves the closing inequality at $a=\FourRoutesA$, $K=\FourRoutesK$ and $\vartheta=\FourRoutesDensity$; it keeps the same $72$ slots, the same prime ranges and the same middle reference laws. It uses the new upper comparisons of \cref{subsec:upper-six-refinements}, the joint mean allocation of \cref{subsec:joint-mean}, the stronger density estimate, and the prefix law of Step~4 below. No result before the improved stage depends on $\vartheta>1$. \Cref{sec:history} (Part~VI, after the proof) records how the explicit exponent developed; no proof in Parts~I--V uses it. The rest of this introduction explains the proof (\cref{subsec:intro:method,subsec:intro:steps}) and what is new in it (\cref{subsec:intro:new,subsec:intro:deligne}), states the closing inequality with its baseline values (\cref{subsec:intro:inequality}) and the kinds of input (\cref{subsec:intro:status}), and ends with a reading guide (\cref{subsec:intro:outline}). It proves nothing; every statement in it is proved later. \subsection{Overview}\label{subsec:intro:method} \begin{figure}[tp] \centering \begingroup \pdfprotrudechars=0 \pdfadjustspacing=0\relax% \renewcommand{\small}{\fontsize{9}{11}\selectfont}% \renewcommand{\footnotesize}{\fontsize{8}{9.5}\selectfont}% \fontsize{10}{12}\selectfont \setlength{\fboxsep}{4pt}\setlength{\fboxrule}{0pt}% \resizebox{\textwidth}{!}{\fbox{% \begin{tikzpicture}[ box/.style={draw,rounded corners=2pt,align=center,inner sep=5pt,execute at begin node={\hyphenpenalty=10000\exhyphenpenalty=10000}, text width=3.4cm,minimum height=1.05cm,font=\small}, ext/.style={box,fill=blue!7}, tool/.style={box,fill=teal!8}, law/.style={box,fill=orange!10}, frame/.style={box,fill=violet!8}, result/.style={box,fill=red!8,text width=7.1cm,thick}, check/.style={box,fill=gray!8,dashed,text width=6.0cm}, arr/.style={-{Stealth[length=2mm]},semithick}, checked/.style={arr,dashed,gray!80!black}, heading/.style={font=\small\bfseries,align=center} ] \node[heading] at (6.15,1.2) {External inputs (Appendices A and B)}; \node[ext] (weil) at (0,0) {Weil bounds,\\Gauss and Jacobi sums}; \node[ext] (angle) at (4.1,0) {Kassabov angles,\\Peyre tensorization$^*$}; \node[ext] (group) at (8.2,0) {$\mathrm{GL}_2(\mathbb F_p)$\\character table}; \node[ext] (geometry) at (12.3,0) {Katz--Sarnak, Deligne,\\trace formula, Euler\\characteristic,\\Ahlgren--Ono}; \node[tool] (counts) at (0,-2.4) {\S12 labellings,\\extension counts}; \node[tool] (corr) at (4.1,-2.4) {\S13 cuts, blocks,\\pinned correlations}; \node[tool] (spec) at (8.2,-2.4) {\S14 spectral criterion;\\\S16 extraction,\\coincidences}; \node[tool] (second) at (12.3,-2.4) {\S15 four-cycle and\\complete cubic kernels;\\trace moments}; \node[tool] (completion) at (4.1,-4.25) {\S17 completion,\\polarization,\\additive repair}; \draw[arr] (weil) -- (counts); \draw[arr] (angle) -- (corr); \draw[arr] (group) -- (spec); \draw[arr] (geometry) -- (second); \draw[arr] (counts) -- (corr); \draw[arr] (corr) -- (spec); \draw[arr] (second) -- (spec); \draw[arr] (corr) -- (completion); \node[law] (prefix) at (0,-6.6) {\S\S19,31 square-clique\\iid prefix, $p\equiv1\ (4)$}; \node[law] (middle) at (4.1,-6.6) {\S\S20--26 middle range:\\signed block laws,\\positive roots, credits}; \node[law] (upper) at (8.2,-6.6) {\S\S27--28 upper range:\\root reweighting,\\six-query comparisons}; \node[law] (index) at (12.3,-6.6) {\S29 tail; external\\index, exact square\\contraction, $K=\FourRoutesK$}; \draw[arr] (completion.south) -- (middle.north); \draw[arr] (completion.south east) -- (upper.north west); \draw[arr] (spec.south) -- (upper.north); \draw[arr] (spec.south west) -- (middle.north east); \draw[arr] (counts.south) -- (prefix.north); \node[frame] (analytic) at (0,-9.0) {Part II: signed H\"older,\\lifts, kernel (App.~C),\\square-step induction}; \node[frame,text width=7.5cm] (comparison) at (6.15,-9.0) {Part III: the comparison theorem\\reference, Gram bracket, signed index form;\\joint comparison and mean allocation}; \draw[arr] (analytic) -- (comparison); \draw[arr] (prefix.south) -- (comparison.north west); \draw[arr] (middle.south) -- (comparison.north); \draw[arr] (upper.south) -- (comparison.north); \draw[arr] (index.south) -- (comparison.north east); \node[result,text width=5.4cm] (closing) at (6.15,-11.1) {\S\S31--33 density moments,\\induction and joint closing:\\$\Theta<\FourRoutesTheta<1$}; \draw[arr] (comparison) -- (closing); \node[result] (theorem) at (6.15,-12.8) {Theorem 1.1:\quad $s(N)\le C N^{1-\varepsilon}$\\with $\varepsilon=\FourRoutesDecimal$}; \draw[arr] (closing) -- (theorem); \node[check,text width=4.3cm] (finite) at (0,-11.1) {Appendix D and \S33:\\exact rational and interval\\certificates of finite inputs}; \node[box,draw=none,text width=12.5cm,font=\footnotesize,anchor=north] at (6.15,-13.75) {$^*$The finite Peyre theorem needed is proved in Appendix~B. Blue: external inputs; green: local tools (Part IV); orange: the construction (Part V); violet: Parts II and III. Solid arrows are principal mathematical dependencies; the dashed arrow is arithmetic verification of finite inputs, and a passing certificate does not verify the reductions.}; \draw[checked] (finite.east) -- (closing.west); \end{tikzpicture}% }}% \endgroup \caption{Principal dependencies of the proof. External inputs feed the local tools of Part~IV; these build the laws of the construction in Part~V, which verify the hypotheses (CP0)--(CP8) of the comparison theorem of Part~III. The selected density moments and induction extend the analytic framework of Part~II; the normalized closing in \cref{sec:four-routes-closing} then gives \cref{thm:main}. The dashed arrow records finite arithmetic checks, whose scope is stated in \cref{subsec:intro:status} and \cref{app:certificates}. The parts are described in \cref{subsec:intro:outline}.} \label{fig:intro:dependencies} \end{figure} The whole proof is organised around one average attached to $A$. We define it in this subsection, show that it is large when $A$ is dense, and then explain how the induction proves that it must in fact be small. The rest of the paper either proves these two bounds or constructs the distributions that make the second bound explicit. \paragraph{The average $Y$.} Write $\alpha=|A|/N$ for the density of $A$, and write $N=\Kint\Lsc$, where $\Kint$ is a fixed number of intervals and $\Lsc$ is the scale. There are $72$ \emph{slots}, forming a set $V$ (Step~1 below gives the exact array). A \emph{label} is an element of a finite group $G_N$ built from residue classes at the primes; a \emph{configuration} is a choice of one label $z_v$ for each slot $v\in V$. Let $F_A$ be the truncated Fourier series of $\one_A$ on $G_N$ (the \emph{Fourier lift} of $A$; see \cref{sec:lifts}). It has mean $\alpha$, but it may take negative values. Finally, let $\mu$ be a probability distribution on configurations, built as a product over blocks of primes. We call $\mu$ the \emph{reference law}, and put \[ Y=\E_\mu\prod_{v\in V}F_A(z_v). \] Thus $Y$ is a $72$-fold Fourier average of $A$: we choose a random configuration from $\mu$ and multiply the values of $F_A$ at its $72$ labels. If $F_A$ were the constant $\alpha$, this would be exactly $\alpha^{72}$. \paragraph{Why $Y$ is large.} The reference law $\mu$ is \emph{reflection positive}: for each of several mirror symmetries of the slots, the matrix that couples the two halves of a configuration is positive semidefinite (\cref{sec:mechanism} informally, \cref{sec:positivity} formally). Repeated Cauchy--Schwarz across these symmetries gives a signed H\"older inequality, and hence \[ \alpha^{72}\le Y. \] The sign of $F_A$ is the point. For a nonnegative function this would be an ordinary moment bound; here reflection positivity is what makes the same conclusion available for the signed lift. In particular, a dense set $A$ forces $Y$ to be large. \paragraph{What we prove about $Y$.} Against this, we prove an upper bound of the form \[ Y\le C\Lsc^{-a}\alpha^{\vartheta}, \] where $a>0$ is fixed and $\vartheta=1$ in the baseline argument; the final argument obtains the stronger exponent $\vartheta=\FourRoutesDensity>1$. The two bounds together give $\alpha^{72-\vartheta}\ll\Lsc^{-a}$, which is the power saving in \cref{thm:main}. The upper bound is proved by induction on the scale. Suppose it failed, and look at the smallest scale $\Lsc$ where it could fail; call this a \emph{least counterexample}. At every smaller scale the bound is already known, and the whole comparison below takes place at this one scale, with the smaller scales available as an induction hypothesis. \paragraph{Forcing six square differences.} At a least counterexample we change the reference law $\mu$ into a law that forces six specified pairs of slots, called \emph{queries}, to receive labels differing by a square class at every prime. For such a law the average is negligible compared with $Y$: roughly, it counts pairs of elements of $A$ at square distance, and $A$ has none. Making this precise is the kernel estimate of Step~3 below; it is the only place where the hypothesis that $A$ is square-difference-free is used directly. The change of law is made in two stages, $\mu\to\lambda\to\nu$. The \emph{first-stage law} $\lambda$ is obtained from $\mu$ by a small number of explicit changes. (A \emph{record} is one weighted summand in the explicit expansion of a local law; a \emph{component} of a signed combination is one nonnegative summand of that combination. The two words are distinct throughout.) The \emph{comparison law} $\nu$ is a finite signed combination of nonnegative laws, each of which \emph{accepts} the six queries: almost surely, each query pair differs by a nonzero square at every field prime (a prime whose coordinate in $G_N$ is $\Fp$) and by a nonvanishing square class at the prime-power coordinates, and the summand has the uniform one-slot marginals required in (CP4). In informal prose we say such a summand \emph{forces} a square difference when only the almost-sure square condition is meant; \emph{accepts} always includes the marginal requirement. Their formal definitions are (CP1), (CP2) and (CP4) in \cref{sec:comparison-theorem}. The law $\nu$ is signed, so it need not be reflection positive, and the lower-bound argument does not apply to it. It is instead controlled at one distinguished mirror symmetry $\iota$, the \emph{reserved cut} (the other symmetries are used for the lower bound). A positive law $\Nbr$ dominates $\lambda$ at this cut, in the sense that the block matrix of cut forms $\bigl(\begin{smallmatrix}\Nbr&\lambda\\ \lambda&\Nbr\end{smallmatrix}\bigr)$ is positive semidefinite (written $\succeq_\iota0$ below), and a second pair of positive laws dominates $\nu$ itself. The symmetric and \emph{skew} (antisymmetric under $\iota$) parts of each change $\nu-\lambda$ are dominated and priced separately. \paragraph{What a price is.} It remains to say what these changes cost. The primes are grouped into \emph{blocks} $\Blk$; write $q_{\Blk}$ for the product of the primes in $\Blk$. Fixing the labels at one block fixes a residue class modulo $q_{\Blk}$, and splitting that class into progressions with square step restricts $A$ to shorter progressions with square step (Step~2 below). Those shorter sets are still square-difference-free, so the induction hypothesis applies to them. This is the only use of the induction hypothesis, and its quantitative form is: \begin{quote} Changing the law at one block $\Blk$ changes $Y$ by at most $(\text{size of the change})\times q_{\Blk}^{2a}\times Y$, up to a factor $1+o(1)$ as $\Lsc\to\infty$. \end{quote} The product (size of the change)${}\times q_{\Blk}^{2a}$ is called the \emph{price} of the change. The ``size'' is a total variation or an operator norm, according to the kind of change, and norms are always taken relative to the true one-half distributions of the record being replaced (its \emph{actual marginals}), not relative to a product approximation; the three precise forms are in \cref{def:price} and are summarised in \cref{subsec:intro:glossary}. Grouping primes into blocks means the factor $q_{\Blk}^{2a}$ is paid once per block rather than once per prime. Character sums bound the sizes: they measure how far the local laws are from independent. The finite certificates of Part~V then verify that, for one fully specified construction, all these sizes are small enough; they check finite inequalities only, not the analytic arguments (\cref{subsec:intro:status}). So the task of the paper can be stated plainly: construct laws that are reflection positive where the lower bound needs it, that force the six square differences where the kernel estimate needs it, and whose total price is strictly less than $1$. These three requirements pull against each other, and most of the paper is about meeting them simultaneously. \paragraph{The six indices and the number $\Theta$.} One point has been suppressed. The prime $2$ and the small primes $p\equiv3\pmod4$ are not coordinates of $G_N$. Each query therefore also carries an \emph{external index}: an interval number and a residue modulo a fixed modulus. A signed average over the six indices expands into $2^6=64$ terms. Every term that couples a query across two adjacent intervals is negligible by the kernel estimate, except when the next interval wraps cyclically from the last interval back to the first; these exceptional terms are the \emph{wrapping} terms, and they are priced separately. Collecting the prices of all the changes above gives a single number, which in the baseline argument is \begin{equation}\label{eq:intro:closing} \Theta=\tfrac{63}{64}\bigl(L_0+\mathcal E\bigr)+J+W+\tfrac{1-m}{64}. \end{equation} Here $L_0$ is the total price of the first-stage change $\mu\to\lambda$; $\mathcal E$ is the total dominated price of the comparison change $\nu-\lambda$ at the reserved cut; $J$ bounds the coupled terms coming from the external indices; $W$ bounds the wrapping terms; and $m>1$ measures how much of the mean (constant-function) part of $Y$ the dominating laws retain (\cref{sec:matching-mean}), so the last term $(1-m)/64$ is a credit. The factor $63/64$ records that the empty term of the $64$-term expansion is the comparison average itself. All symbols are defined fully in \cref{subsec:intro:inequality} and \cref{sec:comparison-theorem}. If $\Theta<1$, then at a least counterexample the priced upper bound for $Y$ is incompatible with the lower bound $\alpha^{72}\le Y$. Hence there is no least counterexample, and the upper bound holds at every scale. This implication is the comparison theorem, Theorem~C (\cref{thm:comparison}); its proof (\cref{sec:comparison-lemmas,sec:comparison-proof}) uses nothing about the particular local laws, and \cref{prop:mech:one-query} shows the whole mechanism with a single query. The rest of the paper verifies the hypotheses of Theorem~C for one explicit construction and evaluates $\Theta$. For \cref{thm:main} the improved stage then uses the joint form of this criterion (\cref{cor:joint-closing}) together with the stronger density induction; \eqref{eq:intro:closing} is its baseline form. \paragraph{Why this shape gives a power saving.} The conversion is worth isolating. Suppose that at some fixed $a>0$, independent of the scale and of $\alpha$, the construction above can be priced with $\Theta<1$. Then $\alpha^{72-\vartheta}\ll\Lsc^{-a}$ at once, so $\eps=a/(72-\vartheta)$: no iteration is needed, and the saving is a fixed power for the elementary reason that the required win does not shrink as $\alpha\to0$. This is also where the quantitative difficulty lies. With only the first-order (Weil) bounds $O(p^{-1/2})$ for the local character sums, the best certified value of $\Theta$ is still larger than $1$ (\cref{subsec:intro:deligne}); the second-order bounds $O(p^{-1})$ of Part~IV, the relative (actual-marginal) form of the local estimates, and the variance and mean subtractions are what bring the total price below $1$ at an explicit value of $a$. \paragraph{Is this a density-increment argument?} In ancestry, yes; in form, no. The classical arguments \cite{PSS88,BloomMaynard} (and \cite{GreenSawhney}) assume that $A$ is dense and square-difference-free, count square differences by Fourier analysis, and deduce that $A$ has larger relative density on a shorter structured set---a progression with square step in \cite{PSS88}, a Bohr set in \cite{BloomMaynard}. Iterating this increment until the density would exceed $1$ bounds $\alpha$. Each step gains only a small factor in density and loses length, so the final saving is smaller than any fixed power of $N$. The present proof uses the same square-step rescaling, but it never produces a denser set. Instead, the induction hypothesis at all smaller scales is used at once, at a least counterexample, in the form of prices: passing to the shorter progressions is what makes a change of law at one block cost the factor $q_{\Blk}^{2a}$. And the quantity being bounded is not the density $\alpha$ itself but the $72$-fold average $Y$. This is where the extra strength comes from. Since $\alpha^{72}\le Y\le C\Lsc^{-a}\alpha^{\vartheta}$ with $\vartheta\approx1$, a single constant-factor win---the inequality $\Theta<1$ at one scale---already gives $\alpha^{72-\vartheta}\ll\Lsc^{-a}$: the $72$ slots amplify one rescaling gain into a power saving, with no iteration and no repeated loss of length. The cost of this amplification is that $F_A$ changes sign, so the positivity that a density has for free must be manufactured (this is the role of reflection positivity), and the change of law must be priced in the actual marginals with second-order character-sum bounds, so that the total price converges at an explicit value of $a$. \paragraph{The eleven ingredients, in order of first use.} The genuine ideas, in the order in which the paper uses them, are: (i)~reflection positivity across mirror symmetries of the slots; (ii)~rescaling by progressions with square step, with an induction linear in the density; (iii)~the kernel estimate of Step~3; (iv)~handling small primes jointly through one signed external index per query; (v)~graph laws made reflection positive by adding correction summands, the principal law itself sometimes reweighted; (vi)~replacements that keep the true one-half distributions, so their differences pair to zero with constants and can be bounded by operator norms; (vii)~controlling a signed, non-positive comparison law by domination at one cut, with symmetric and antisymmetric changes bounded separately; (viii)~signed combinations over a whole block of primes whose first-order change is purely antisymmetric (adding an edge together with its mirror is the simplest case); (ix)~subtracting variance and related savings and retaining the common mean, instead of bounding every term trivially; (x)~square cliques for the primes $p\equiv1\pmod4$; (xi)~exact star factorisation: a \emph{star} is a set of cross pairs sharing one endpoint; for a half law invariant under the square-affine maps $z\mapsto rz+t$ with $r$ a square unit, its Gram matrix is computed exactly, so star sums reduce to finite matrix tests. \paragraph{What is routine verification rather than a new idea.} The spectral certificates for specific graphs, the matching partitions and their extraction bookkeeping, the local constants of each prime range, the block partitions and their degree sums, the completion weights, the dominator witnesses, the tabulated middle prices, and the arithmetic that evaluates $\Theta$. They sit behind lemmas stated once, with the finite inputs in the appendices: monotone majorants are checked at one endpoint, and polynomials with nonnegative coefficients are evaluated at upper prices. \subsection{The proof in five steps}\label{subsec:intro:steps} The five steps are: (1)~a $72$-fold average at least $\alpha^{72}$; (2)~rescaling to shorter progressions with square step; (3)~the kernel estimate, the only use of no square differences; (4)~local distributions, by prime range; (5)~summing the error bounds and completing the induction. \emph{Step 1. A $72$-fold average that is at least $\alpha^{72}$.} Let $N=\Kint\Lsc$, where $\Kint=\PushK$ is a fixed number of intervals and $\Lsc$ is the scale. The labels live in the finite group $G_N=\prod_p\Z/p^{e_p}\Z$, the product over three kinds of primes: the primes $p\equiv1\pmod4$ below $\Pfour=2^{512}$, with $e_p=2\mcl$ and $\mcl=8192$; the primes $p\equiv3\pmod4$ in $[Q_3,\Pfour)$, where $Q_3=19\,951\,586$; and all primes in $[\Pfour,N^{1/20}]$; the last two kinds have $e_p=1$. The prime $2$ and the primes $p\equiv3\pmod4$ below $Q_3$ are not coordinates; they enter through the external index of Step~4. The lift $F_A(z)=\sum_\xi\widehat{\one_A}(\xi)e(z\cdot\xi)$ sums, over the characters $\xi$ of $G_N$ of conductor at most $N^{1/20}$, the normalized exponential sums $\widehat{\one_A}(\xi)=N^{-1}\sum_{n\in A}e(-n\xi)$; it has mean $\alpha=|A|/N$, but it may be negative. The $72$ slots are $V=(\Z/6\Z)^2\times\{0,1\}$: two six-chamber coordinates and a layer. Given a probability law $\mu$ on labellings $z\colon V\to G_N$, put $Y=\E_\mu\prod_{v\in V}F_A(z_v)$ (\cref{def:record:functional}). Reflection positivity says that, at specified cuts of the slots, the matrix of the two halves is positive semidefinite. Here the cuts are the three chamber reflections of each six-chamber coordinate and the reserved cut $\iota$, which flips the layer; their folds sort $V$ (\cref{lem:slot-array}). Repeated Cauchy--Schwarz then gives a signed H\"older inequality. Unlike an ordinary moment, this still works for functions that change sign. Reflection positivity entered through statistical mechanics and constructive field theory \cite{FrohlichSimonSpencer76,DysonLiebSimon78,FrohlichLieb,FILS, GlimmJaffe87}; in combinatorics the same positive-semidefinite formalism underlies graph-homomorphism inequalities and flag algebras \cite{ConlonLee,HatamiNorine11,Razborov07,LovaszGraphLimits12, BorgsChayesLovaszSosVesztergombi08}. The finite version needed here is \cref{thm:holder}. For the reference law $\mu=\bigotimes_{\Blk}\mu_{\Blk}$ of the construction, a product of laws on blocks of primes that are reflection positive at all these cuts and square-affine invariant, it gives $\alpha^{72}\le Y$ (\cref{lem:record:holder}). \emph{Step 2. Rescaling to shorter progressions with square step.} Fixing the labels at a block of primes specifies an integer residue class. Splitting it into progressions of square step rescales the problem to a shorter interval while preserving square-difference avoidance; the step is the least square divisible by the modulus (\cref{lem:record:fibre-scale}). The errors in this comparison are controlled in \cref{sec:lifts,sec:scale-comparison}. At a least counterexample to $Y\le C\Lsc^{-a}\alpha$ (a smallest scale where the bound fails, so it holds at every smaller scale) this gives the prices of \cref{subsec:intro:method}: each slot contributes a factor $(q_{\Blk}^2)^{a/72}$, hence $q_{\Blk}^{2a}$ over $72$ slots, times the size of the change at $\Blk$. The moment bounds are linear in $\alpha$, so the induction keeps the full density factor: from $\alpha^{72}\le Y\le C\Lsc^{-a}\alpha$ one obtains $\alpha\le C'N^{-a/71}$, which is the conversion $\eps=a/71$ (\cref{thm:record:lineardensity}). \emph{Step 3. The kernel estimate: the only use of no square differences.} Suppose two slots are placed in adjacent intervals and, at every prime, their labels are forced to differ by a square class. Then the corresponding Fourier average is negligible: roughly, it counts pairs from $A$ at square distance, and $A$ has none. Making this precise is a circle-method calculation with a kernel supported on squares, for Fourier frequencies up to $N^{1/20}$ (\cref{sec:kernel,app:kernel20}). This is the only step that directly uses the defining property of $A$. Everything else in the proof is about arranging, at small price, that six such forced pairs occur. \emph{Step 4. Local distributions, by prime range.} No single elementary estimate is efficient for every prime, and the class of $p$ modulo $4$ matters. If $p\equiv1\pmod4$, then $-1$ is a square and the strict-square relation $y-x\in\Qsq$ is symmetric. If $p\equiv3\pmod4$, exactly one of $y-x$ and $x-y$ is a nonzero square, and the relation is a tournament, the Paley tournament. The construction has five ranges. \begin{itemize} \item \emph{The small modulus.} The external modulus is $\Mzero=2^{129}\prod_{3\le p1$ retained from the six indices (\cref{sec:matching-mean}). In the final closing, higher mean contributions are allocated jointly against the same labelled positive comparison coefficients before upper prices are substituted; only the residual series with nonnegative coefficients is then completed (\cref{cor:joint-closing,subsec:joint-mean}). If only the variance and dominator savings were removed, with all other credits kept, $\Theta$ would exceed $1$ by about $0.46$ in the baseline; see \cref{subsec:intro:inequality}. \item[Improving the power of $\alpha$ in the induction] The baseline moment bounds are linear in the density, with conversion $\eps=a/71$. The final argument strengthens this to $\alpha^{\FourRoutesDensity}$. Most laws are controlled by grouping labels in pairs; rare cases where many labels coincide are instead handled by fixing (\emph{pinning}) the coinciding labels and rescaling the resulting shorter progressions, and a new prefix law with independent labels removes repeated-label concentration. These steps are proved after the baseline closing (\cref{sec:density:moments-prefix} and \cref{sec:density-upgrade}). The comparison error is bounded before the operator reduction, and the square-step main term is then estimated with the actual folded laws and their mixed moments, as in \cref{prop:density:production}. \item[A kernel for larger cutoffs] The actual-square kernel is proved for Fourier cutoffs up to $N^{1/20}$ and for prime-power moduli (\cref{app:kernel20}), so that the class-one primes can carry labels modulo $p^{2\mcl}$. \item[Estimates are verified at explicit prime thresholds] The middle range starts at $Q_3=19\,951\,586$ and the upper range at $\Pthree=167\cdot2^{40}$. These are not asymptotic placeholders: at the chosen thresholds, exact rational matrices and interval inequalities verify the hypotheses of the analytic lemmas, and monotone majorants carry each check to all larger primes. \Cref{app:certificates} states precisely which assertions are computational. \end{description} \paragraph{The general machinery and the earlier explicit design.} The first explicit versions of this argument used the slot array $(\Z/6\Z)^3$, with $216$ slots, and a reserved cut that was a chamber reflection of the third coordinate. Most of the general machinery of Parts~II--IV was developed for that $216$-slot design: the chessboard calculus on products of reflection coordinates; lifts, moments, conductor decay and the actual-square kernel; the external index and its coupling; graph laws with Weil-type insertion counts and pinned influence; the spectral criterion with its coupling block, its witness extraction and the four-cycle bound; completions by folds, matchings, merges and constants; and the comparison of three laws, an all-cut reference, an intermediate law and an accepting law, by polarization and additive repairs that keep the actual conditional marginals. Parts~II--IV state it once, in the generality the final design uses. The final proof is that design re-instantiated on $72$ slots, with new local laws and four structural substitutions (\cref{tab:walk:substitutions}): a two-point layer whose flip is the reserved cut replaces the third six-chamber coordinate, which changes the conversion at the same $a$ from $a/(216-\vartheta)$ to $a/(72-\vartheta)$, hence to $a/71$ for the density-linear induction with $\vartheta=1$; six disjoint one-way queries with a common signed index replace coupled families of amplified edges and their obstruction covers; the comparison law is not reflection positive, and is controlled at the reserved cut by a positive $2\times2$ block; and the primes are divided by their class modulo $4$ into the ranges of Step~4. What the final theorem does not use are the instances of the $216$-slot design: its particular laws, constants and certificates, and the proofs of its checkpoints. \Cref{sec:design-walk} explains each substitution as the answer to a quantitative failure, and \cref{subsec:history:216} lists what survives of each part of that design. \subsection{Where the Deligne bound enters}\label{subsec:intro:deligne} It is useful to separate first-order and second-order character sums. For one square constraint, or for counting extensions of one label at a time, the relevant sums contain one quadratic character of a polynomial with distinct roots. Weil's bound \cite{Weil48,Weil49,Schmidt76} gives square-root cancellation: after the normalisations of \cref{sec:labellings}, the relative error is $O(p^{-1/2})$. Gauss and Jacobi sums evaluate the constant Fourier blocks exactly \cite{BerndtEvansWilliams,IrelandRosen}. These tools suffice for a large part of the construction and already appear, in a simpler form, in the OpenAI argument. The difficulty is that the spectral estimates are conditional. One has fixed part of a graph labelling and must compare the joint law of two remaining labels with a product law. Errors from two one-variable counts can correlate. Bounding each separately by $O(p^{-1/2})$ is not enough for the negative spectral side: several terms must be $O(p^{-1})$ after normalisation, uniformly in the fixed labels and in the polynomials arising from the graph. A model sum is \[ \sum_{y,z\in\F_p}\chi\bigl(f(y)g(z)(y-z)\bigr), \] where $\chi$ is the quadratic character and $f,g$ have controlled degrees and distinct roots. This is the content of \cref{thm:dl:H2}. There is no single black box in the proof. Four algebraic-geometric facts are combined: \begin{enumerate}[label=(\roman*)] \item The Grothendieck--Lefschetz trace formula rewrites the character sum as a trace of Frobenius on compactly supported cohomology. \item For the family of curves $y^2=f(x)(x-z)$, Katz--Sarnak \cite{KatzSarnak} identify the relevant sheaf: it is lisse, tame, pure and geometrically irreducible, with large symplectic monodromy. In elementary language, as the parameter $z$ moves there is no hidden invariant direction in which all the errors point the same way. \item The Grothendieck--Ogg--\v Safarevi\v c formula bounds the dimension of the cohomology in terms of the degrees and ramification. This is where the explicit, degree-dependent constant comes from. \item Deligne's theorem on weights \cite{DeligneWeilI,DeligneWeilII} bounds the Frobenius eigenvalues. After the normalisations in the spectral problem, this yields the required $O(p^{-1})$ rather than $O(p^{-1/2})$. \end{enumerate} The precise external statements are isolated in \cref{app:external} (\cref{thm:prelim:ks}); their conversion into the estimates used by the local laws is carried out in \cref{sec:dl}. A reader willing to accept \cref{thm:dl:H2} and the second moments of \cref{sec:dl} as named character-sum estimates can read the rest of the proof without following the sheaf argument. A second, different second-order input concerns the complete bipartite graph $K_{2,2}$. Its character kernel is invariant under $\mathrm{PGL}_2(\F_p)$. The character table of $\mathrm{GL}_2(\F_p)$ therefore decomposes it into representation blocks, and Gauss--Jacobi identities bound those blocks. The resulting normalised estimate is $2/p$ (\cref{thm:dl:K}). This is representation theory, not the Katz--Sarnak sheaf input, although both feed the same spectral envelopes. In the construction these bounds are used wherever two remaining labels must be compared with independent labels: in the spectral bounds for middle and upper laws (\cref{sec:spectral}), in the non-star terms of the character expansion (\cref{sec:extraction}), and in conditional distributions given a fixed middle label. The same sheaf family also gives mean-square bounds for trace functions with one free label, used for the two principal upper cuts below $2^{52}$ (\cref{thm:record:direct-star}). Precise entry points are cited in each Part~V section. Two later local estimates should be distinguished. The complete $K_{3,3}$ character kernel is bounded by an exact polynomial-resultant Gram identity, not by the cohomological input above (\cref{thm:cubic-resultant}). The centred rectangle bound uses the symmetric square of the same Legendre sheaf, through the Mellin eigenvalue estimate of \cref{lem:rectangle-mellin}; its weaker $128q$ form avoids that symmetric-square step (\cref{thm:rectangle-gram}). This is the same circle of ideas as the modern theory of algebraic trace functions. Fouvry--Kowalski--Michel recast many character and exponential sums as Frobenius traces, then use Deligne's bounds and monodromy to show that no main term survives \cite{FKMPrimes14,FKMTwists15}. Will Sawin's work is a prominent part of that programme, both over the integers---bilinear forms with Kloosterman and more general trace functions \cite{KMS17,KMS20,FKMSBilinearTrace25}---and over $\mathbf F_q[T]$, where the geometry is strong enough to prove function-field Chowla/twin-prime statements and near-square-root cancellation for factorization functions \cite{SawinShusterman22,SawinFactorization24,KowalskiBourbakiSawinShusterman}. His quantitative sheaf theory \cite{SawinQST23} also addresses the same practical question faced here: after Deligne gives square-root size for Frobenius eigenvalues, how does one bound how many of them there are, uniformly and explicitly? The overlap is methodological rather than a direct dependence. We do not quote a theorem of Sawin. Our sheaves come from one fixed family $y^2=f(x)(x-z)$ over $\F_p$, arising from two remaining labels in the graphs of the local laws; the required output is not an asymptotic cancellation statement but an explicit $O(p^{-1})$ spectral envelope with a degree-dependent constant that can be inserted into the spectral caps at explicit thresholds. The Sawin--Shusterman results cited above concern increasing polynomial degree over a fixed finite field satisfying their size and characteristic hypotheses. What is shared is the mechanism: interpret a character sum cohomologically, use monodromy to exclude a hidden main term, bound conductors and cohomology dimensions, and let Deligne's weights supply the cancellation. One further input is modular. The second moment of the neighbourhood count behind the variance credits of the middle range (\cref{lem:record:weighted-moment}) contains the twisted second moment $\sum_\lambda\chi(\lambda)T_\lambda^2$ of the point counts $T_\lambda=\sum_y\chi\bigl(y(y-1)(y-\lambda)\bigr)$ of the Legendre family of elliptic curves, for which Weil's bound alone gives only $O(p^2)$. Ahlgren and Ono \cite{AhlgrenOno2000} evaluate it as $-p-a(p)$, where $a(p)$ is the $p$-th coefficient of the weight-four cusp form $\eta(2z)^4\eta(4z)^4$ of level~$8$, and Deligne's proof of the Ramanujan--Petersson conjecture \cite{DeligneWeilI} gives $|a(p)|\le2p^{3/2}$ (\cref{thm:ahlgren-ono}). With this evaluation the normalised second moment $\E[P_{\rm adm}\mathcal W^2]/p^2$ of \cref{lem:record:weighted-moment} is at most $5/p+O(p^{-3/2})$, while the general bound for the graph moments it contains gives only $10/p+O(p^{-3/2})$. Through the root-half variances of the middle roots it enters the recomputation (restoration) of the variance credits after a tilt changes the root half marginal (\cref{sec:variance}) and the cut caps of the middle roots (\cref{subsec:middle-l20,sec:positive-roots}). \paragraph{Why the qualitative result did not need second-order bounds.} They were unnecessary, not unavailable. The OpenAI theorem asserts the existence of some $\eps>0$. For that purpose one may choose an enormous number of slots and an enormous prime threshold, and lose very large absolute constants, provided the errors eventually become small. The elementary one-edge Gauss-sum calculation and telescoping graph estimates in \cite[Section~2]{OpenAI} are enough for that qualitative conclusion. An explicit exponent is stricter in three ways. First, $d=72$, so there is no huge denominator in which to hide losses when passing from the functional exponent $a$ to $\eps=a/71$. Secondly, the laws must be certified at named finite thresholds, principally $Q_3=19\,951\,586$ in the middle range and $\Pthree=167\cdot2^{40}$ in the upper range. Thirdly, the closing sum has no room for a correlated first-order term: the certified spectral caps, completion variances and upper-root bounds are evaluated with the second-order estimates, and the baseline closing margin $1-\Theta$ is only about $2.7\cdot10^{-11}$ (the final joint closing margin is $>2.29\cdot10^{-7}$), so the certified exponents depend on them. The closing certificates use the four-cycle bound, Deligne's theorems, Katz--Sarnak and the evaluation of Ahlgren and Ono to obtain the second-order bounds entering that budget. This explains their role in this proof; it does not establish that these inputs are necessary for a comparable exponent by another argument, and whether a smaller exponent can be certified with first-order bounds alone has not been tested. \subsection{The closing inequality \texorpdfstring{$\Theta<1$}{Theta<1} in the baseline (\texorpdfstring{$\vartheta=1$}{vartheta=1})}\label{subsec:intro:inequality} The comparison theorem (\cref{thm:comparison}, Theorem~C) reduces the baseline ($\theta=1$, where $\theta$ denotes $\vartheta$ in Part~III) to nine hypotheses (CP0)--(CP8)---standing data, reference law, first-stage law, domination at the reserved cut, comparison law, optional sharper bounds for named families of simultaneous record changes, dominators for the comparison law, mean energies, and admissibility---and to the single inequality $\Theta<1$ for the number \eqref{eq:intro:closing} with $k=6$ queries on $d=72$ slots, where \begin{gather*} \mathcal E=B\bigl(e^S\cosh A-1\bigr)-D,\qquad J=Be^T\Bigl(\frac{R_I}2\Bigr)^6,\\ W=Be^{S+A}\Bigl[\Bigl(1+\frac{R_I}{2}\,\Kint^{-35/36}\Bigr)^6-1\Bigr]. \end{gather*} Here $S$ and $A$ are the total symmetric and skew prices of $\nu-\lambda$, $B$ is the energy factor of the law dominating $\lambda$ (so $\mathcal E$ is the dominated price bound with savings $D$ subtracted), $T$ is the total dominator price entering through $e^T$ (not an exponent of $p$), $R_I=\E(\Kint\operatorname{sq}(D))^{2a/72}$ is the conductor factor of one external index (\cref{def:hyb:coupled}), and the displayed formula for $\mathcal E$ is the baseline specialisation of the general complete-polynomial bound $\Psi$ of Theorem~C (that is, an admissible upper bound for $\Psi$ at the baseline prices, in the notation of \cref{thm:comparison}). The $63/64$ factor records that the empty term of the signed-index expansion is the comparison average itself; in $J$ each query contributes $R_I/2$; $W$ bounds the terms in which every active query wraps from the last interval to the first; and $m>1$ lowers $\Theta$ through $(1-m)/64$ (\cref{rem:cp:reading}). Each quantity is constructed in Part~V. The first stage $\lambda$ differs from $\mu$ only on middle blocks; its price $L_0$ and the dominating law $\Nbr$, with energy factor $B=e^{U_0}+R_{\rm err}$ (where $U_0$ is the total price of the positive records added to $\mu$ in the bracket and $R_{\rm err}$ is the remaining two-cut first-stage error, \cref{def:cp3}), are constructed in \cref{sec:middle-frame}. The prices $S$ and $A$ are summed over all prime ranges: the deleted coincident-label event of the $p\equiv1\pmod4$ prefix (\cref{sec:frontier:iidprefix}, in the baseline counted in $S$ only), the middle-range replacements (\cref{sec:middle-records}), the upper-range replacements (\cref{sec:upper-comparison}), and the large primes (\cref{sec:tail-index}). The savings $D$ are the variance savings of \cref{sec:variance} together with the dominator savings of \cref{sec:envelopes} for even products of skew differences. The price total $T$ and the mean constant $m$ come from the dominators of $\nu$ in \cref{sec:matching-mean}; $R_I$, $J$ and $W$ are computed from the index law at $\Kint=\PushK$ (\cref{sec:tail-index}). \Cref{sec:closing} assembles the baseline $\Theta$; middle prices first computed at the evaluation exponent $a_0=\PushAnchor$) bounds, rounded outward; $\ldots$ marks an exactly defined number (\cref{tab:closing-values} gives more digits).} \label{tab:intro:values} \small \begin{tabular}{@{}lll@{}} \toprule term & meaning & value\\ \midrule $t$ & repricing factor $e^{2(a-a_0)L}$ of the middle prices & $1.0000000616512\ldots$\\ $U_0$ & exponent in $e^{U_0}$ below (dominating law) & $<0.84691$\\ $B$ & energy factor $e^{U_0}+R_{\rm err}$ of that law & $<2.33263$\\ $L_0$ & total price of $\mu\to\lambda$ & $<4.7634\cdot10^{-4}$\\ $S$ & total symmetric price of $\nu-\lambda$ & $<0.014555$\\ $A$ & total skew price of $\nu-\lambda$ & $<0.96928$\\ $D$ & savings; of these, variance part $D_{\rm var}>0.0099585$ & $>0.46685$\\ $\mathcal E$ & dominated bound $B(e^S\cosh A-1)-D$ & $<0.76897$\\ $T$ & dominator price total (in $e^T$) & $<0.60760$\\ $R_I$ & conductor factor of one index, $\Kint=\PushK$ & $<1.24714$\\ $J$ & coupled term $Be^T(R_I/2)^6$ & $<0.25177$\\ $W$ & wrapping bound & $<3.8345\cdot10^{-5}$\\ $m$ & mean constant (trivial value $1$) & $>1.58994$\\ $\Theta$ & closing number \eqref{eq:intro:closing} & $<\PushTheta$\\ \bottomrule \end{tabular} \end{table} The certificate (\cref{cert:closing}) evaluates $\Theta$ in exact rational and outward interval arithmetic and gives $\Theta<\PushTheta$ (baseline), so that $1-\Theta>2.673\cdot10^{-11}$. In round numbers, $(63/64)(L_0+\mathcal E)$ contributes about $0.758$, $J$ about $0.251$ and $W$ about $4\cdot10^{-5}$, and $(1-m)/64$ about $-0.0092$. The exponent $a$ is chosen so that $\Theta<1$ holds. Every price grows with $a$ through $q_{\Blk}^{2a}$, so a larger $a$ needs smaller local bounds. The displayed point is feasible; no optimality is claimed. The construction itself is specified in \cref{sec:design} (\cref{def:record:parameters}), and \cref{tab:hypotheses} lists, for each hypothesis of Theorem~C, the statement of Part~V that verifies it. \subsection{Proof inputs and verification}\label{subsec:intro:status} The proof has three kinds of input, and the paper keeps them separate. First, there are the arguments proved in the text: Parts~II--III (positivity, the kernel estimate, rescaling and induction, and the comparison theorem) and the local estimates of Part~IV. They occupy most of the paper and do not depend on the numerical choices of Part~V. Secondly, there are named external theorems: Weil's bound for character sums of polynomials (\cref{thm:weil}); the explicit Chebyshev bound of Bennett, Martin, O'Bryant and Rechnitzer \cite{BMOR18} for primes $p\equiv3\pmod4$ (\cref{thm:bmor}); Kassabov's angle inequality (\cref{thm:kassabov}); the character table of $\mathrm{GL}_2(\F_p)$; and, for the second-order sums, the $\ell$-adic formalism: the Grothendieck--Lefschetz trace formula, the cohomology of curves, Deligne's theorem on weights, the Grothendieck--Ogg--\v Safarevi\v c formula and the Katz--Sarnak description of the family $y^2=f(x)(x-z)$, including its local monodromy at the finite roots; and the evaluation by Ahlgren and Ono of a twisted second moment of the Legendre point counts, with Deligne's bound for the coefficients of a modular form (\cref{thm:ahlgren-ono}). Their exact entry points are stated near the sections that use them and collected in \cref{app:external}; \cref{fig:intro:dependencies} is a compressed map. Peyre's theorem is proved in the finite form needed (\cref{app:peyre}), the Gauss and Jacobi sums are evaluated in \cref{sec:notation}, and the other prime sums are exact finite computations or sums over all integers. Thirdly, there are finite certificates. A \emph{checked inequality} is a single finite matrix or numerical inequality verified by exact rational or outward-interval arithmetic; a \emph{certificate} packages such verifications and proves nothing analytic. Examples are the thirteen completion inequalities for each of the $33$ middle intervals, the positivity tests for the middle spectral bounds, and the $32\,550$ completion and domination inequalities for the $310$ upper intervals, together with threshold checks and the evaluation of $\Theta$. \Cref{app:certificates} lists every finite inequality used, with its verification method and data file (\cref{tab:cert:finite}). A successful run verifies those finite assertions and the identity of their inputs; it is not a formal verification of the analytic reductions or of the external theorems. This work was developed in parallel lines of work assisted by AI models (OpenAI Codex and Anthropic Claude models) and reviewed internally by AI models, including independent re-implementations of the finite computations; the closing number has been computed by two separately written programs; on each of the $45$ compared scalar components of the closing evaluation (\cref{cert:closing}) their outward-interval enclosures overlap. The final joint closing also has author and independent complete assemblies (\cref{cert:four-routes-closing}). These reviews are internal, not external referee reports; \cref{subsec:obs:reviews} states their scope. \subsection{Terminology used throughout}\label{subsec:intro:glossary} The proof uses several dozen nouns with precise, nonstandard meanings. Each is defined formally where it first becomes a mathematical object (noted below); this subsection gives a one-sentence meaning usable from the start, so that roadmaps and theorem statements can be read in order. Where one English word has several meanings, the entry separates them; the bare ambiguous word is not used in titles. \emph{Slots, configurations, and laws.} A \emph{slot} is one of the $72$ positions $v\in V=(\Z/6\Z)^2\times\{0,1\}$ at which the Fourier lift $F_A$ is evaluated in $Y=\E_\mu\prod_vF_A(z_v)$ (formally \cref{sec:positivity}). A \emph{configuration} is a map $z\colon V\to G_N$; $z_v$ is its \emph{label} at $v$. A \emph{law} is a probability or finite signed distribution on configurations. The \emph{reference law} $\mu$ is the reflection-positive product law defining $Y$; the \emph{first-stage law} $\lambda$ is $\mu$ after the small modifications of (CP2); the \emph{comparison law} $\nu$ is the signed law of (CP4) whose nonnegative summands accept the queries (below). A \emph{cut} is a mirror symmetry of $V$ with a chosen plus half; the \emph{reserved cut} $\iota$ flips the last coordinate and is reserved for the domination in Part~III, the other cuts serving the lower bound. A law is \emph{reflection positive} at a cut if the matrix coupling the two halves is positive semidefinite. A \emph{query} is one of six fixed disjoint ordered slot pairs whose difference $\nu$ forces to be a square; \emph{forces} means the square condition holds almost surely, while \emph{accepts} (in (CP4)) means in addition the required uniform one-slot marginals and the conditions \ref{it:record:R4} and \ref{it:record:R5} of \cref{sec:lifts} hold, with nonvanishing square classes at the prime-power coordinates. Graph \emph{edges} (Part~IV) are different from queries and carry only the field-prime square condition. \emph{Records and components (distinct).} A \emph{record} is one indexed weighted summand in the explicit expansion of a local law (formally \cref{def:cp:records}, where the phrase ``nonnegative measure'' must be read as this summand sense; differences of records are signed). A \emph{component} of $\nu_{\Blk}=\sum_ic_i\nu_{\Blk,i}$ is one nonnegative summand $\nu_{\Blk,i}$ of the signed combination. Records are what is changed in $\nu-\lambda$; components are what must accept. Where the text below calls a computer file a ``record'' (in certificate descriptions), read \emph{data file}; the mathematical meaning above is the only one used in statements. An \emph{actual marginal} is a one-half distribution computed from the law itself, not from a product or uniform model; \emph{shared labels} $s$ are auxiliary conditioning variables in \cref{def:price}(b) such that, conditional on $s$, a law splits across a cut. A record difference that \emph{annihilates constants} has zero pairing with constant half-functions, which is why it can be priced by an operator norm. \emph{Prices.} Fix a block $\Blk$ of primes with product $q_{\Blk}$. The \emph{price} of a signed measure $\zeta$ is $\|\zeta\|_{\mathrm{var}}q_{\Blk}^{2a}$; a \emph{sharp price} is $wd_\zeta q_{\Blk}^{2a}$, where $w$ is the weight of the record carrying $\zeta$ and $d_\zeta$ is the uniform bound in the shared-label decomposition of \cref{def:price}(b); an \emph{operator price} is a weight times an operator norm in the actual half marginals times $q_{\Blk}^{2a}$. An \emph{upper price} is any number at least the price. The noun \emph{cost} in the text below always means one of these prices or a class bound just defined; it is never a fourth, undefined quantity---when in doubt, replace ``cost'' by the price displayed in the same paragraph. In (CP5) a \emph{class cost} $c_{\mathcal C}$ is the scalar in the special case $\varphi=c_{\mathcal C}\pi$, in which the class-bound polynomial $\varphi$ is a multiple of the monomial $\pi$, the product of the prices of the selected records; the two are not the same. The superscripts in $y^{\rm arm}$, $y^{\rm lead}$, $y^{\rm rem}$ (and their totals $A^{\rm arm}$, $A^{\rm lead}$, $A^{\rm rem}$) are labels for three auxiliary upper prices attached to one skew record in the degree-class replacement of \cref{lem:record:record-expansion}(v) (the formal degree of a record type is the exponent of $r=p^{-1/2}$ in its graded completion weight, \cref{def:patterns}): the first, the raw-arm price, is the auxiliary price whose product over the records of a selection is the first term of the class bound there, and the second and third split the full skew price into its leading star part and a remainder. \emph{Repricing} converts prices computed at an evaluation exponent $a_0$ to the theorem exponent $a\ge a_0$ by powers of $q_{\Blk}$; the inequality needs $a\ge a_0$. A \emph{saving} is a proved amount subtracted from a price bound; the mean constant $m$ is exceptional, being a lower bound added to an energy (hence $(1-m)/64$ in $\Theta$). A \emph{robust} bound (\cref{def:robust}) is one whose $o(1)$ error comes only from the two analytic remainders allowed in Part~II; it is used in (CP5) and (CP7). A \emph{complete polynomial} $\Psi$ is a power series with nonnegative coefficients dominating every simultaneous-change bound coefficientwise; it is defined in the remark after Theorem~C in \cref{sec:comparison-theorem} and developed in Part~III---read that definition before applying Theorem~C with families. \emph{Dominations (four uses of ``envelope'').} A $2\times2$ block $\bigl(\begin{smallmatrix}M&K\\K^*&M'\end{smallmatrix}\bigr) \succeq_\iota0$ of cut matrices implies $|Q_K(x,y)|\le Q_M(x,x)^{1/2}Q_{M'}(y,y)^{1/2}$ and is called a \emph{bracket} at $\iota$; the bracket of (CP3), dominating $\lambda$ by $\Nbr$ at the reserved cut, is also called the \emph{reserved Gram bracket}. The \emph{direct Gram} is the Gram matrix computed jointly for a reference fold record and its signed replacement (\cref{subsec:record:direct_gram}), rather than from separate norm bounds for the two. (CP3) brackets $\lambda$ by $\Nbr$; (CP6) brackets $\nu$ itself by $M_L,M_R$ (called \emph{matching envelopes} in (CP6) and \emph{dominators} in prose, to distinguish them from the \emph{matching records} $E_0,E_1$); (CP4) record differences are bracketed by diagonal envelopes; Part~V \cref{sec:envelopes} uses \emph{dominating matrices} $D$ with $-D\preceq T\preceq D$ (``positive'' means positive semidefinite there). Where \emph{envelope} occurs without a qualifier below, the display in the same paragraph identifies which of the four is meant. Depth tails $\delta_{p,j}$ bound the norm of the index shift operator $T$ on the exact-conductor sector of depth $j$ at $p$; $R_I$ is their averaged factor (\cref{def:hyb:coupled}). \emph{Prime packaging.} An \emph{atom} is one tensor factor of $\mu$; a multi-prime middle or upper atom is a \emph{prime block} $\Blk$ with $\sum_{p\in\Blk}\log p\le L$ ($L=570$ in the middle range; this roman $L$ bounds $\log q_{\Blk}$ and is not the scale $\Lsc$). Consecutive blocks sharing constants form $33$ middle prime intervals (called \emph{pieces} in Part~V displays) and $310$ upper prime intervals (called \emph{bands}); no law lives on a prime interval. Unqualified, \emph{interval} in the index sections means one of the $\Kint$ subintervals of $[N]$, never a prime interval. ``Piece'' also occurs in Part~II for a Fourier support component $f_U$; the two senses are distinguished as \emph{middle interval} versus \emph{support component}. The \emph{prefix} is the range $p\equiv1\pmod4$, $p<2^{512}$; \emph{large primes} $p\ge2^{512}$ are one atom each (the word \emph{tail} is used only with the qualifier \emph{large primes} or \emph{depth tail}). A \emph{graph labelling} is a map $W\to\mathbf F_p$ sending each directed edge to a nonzero-square difference; \emph{injective} is a separate adjective, and $\lambda_p(G)$ is uniform on the injective ones (\cref{sec:labellings}). The weight-$1$ twelve-label summand is called the \emph{principal law} (in Part~V, the \emph{root}); its nonnegative reweightings are \emph{tilted laws}. \emph{Completion} adds the four smaller summand types making a graph law reflection positive; \emph{polarization} dominates the two nonaligned fold records at a chamber cut by the two matching records plus a merge correction, in the cut order at that cut; a \emph{replacement at fixed marginals} (called a \emph{repair} in Part~V) substitutes a forcing law with exactly the replaced law's half marginals. Part~V distinguishes \emph{kept} (already forces), \emph{deleted} (dropped, mass priced), \emph{repaired one-way} (rebuilt from two half copies and the projected queries), and \emph{replaced densely} (old cross graph kept, missing required edges added and the unrequired old edges meeting them softened); ``repair'' never means a small perturbation. \emph{Patterns, folds, and channels.} A \emph{pattern} is a map $\phi\colon\Z/6\Z\to O$ into a small set of \emph{objects} saying which object supplies the label at each of the six positions of one chamber coordinate (\cref{def:patterns}): the identity (the root, type~$\rm L$), the three \emph{folds} $F_0,F_1,F_2$ (type~$\rm D$), the two \emph{matchings} $E_0,E_1$ (type~$\rm S$), the six \emph{merges} (type~$\rm R$), and the constant maps (type~$\rm C$). A \emph{fold record} is a record using a fold pattern, and its \emph{fold chamber} is the chamber cut at which it is diagonal. A fold is \emph{aligned} at a chamber cut when that cut is its fold chamber, so that it is diagonal, hence positive, there; at the other chamber cuts it is \emph{nonaligned}. A \emph{folded copy} (also \emph{reserved-folded copy}) of a one-layer record is that record placed on the reserved diagonal, $\operatorname{Diag}_\iota(\,\cdot\,)$, with the same one-layer labels on both layers; this is the sense in names such as the folded matching records and the measures $F_{\rm fold}$, $E_{\rm fold}$ of \cref{def:record:frame}. This is a different use of the word from Part~II, where the \emph{folds} $\phi_\pm$ of a cut (\cref{def:sorting}) are the two slot maps copying one half of $V$ onto all of $V$, and a \emph{folded energy} is the energy of such a copied input. At one prime $p\equiv3\pmod4$ the four \emph{Paley channels} $\mathsf A,\mathsf B,\mathsf C,\mathsf D$ are the explicit kernels $\chi(\text{difference})$ between labels of the two halves of a fold record \eqref{eq:middle:channels}; a monomial in the channels is a \emph{star monomial} if all its edges share one endpoint and a \emph{nonstar} otherwise. \emph{Further nouns in Parts~IV--V.} A \emph{chamber} is one $\Z/6\Z$ coordinate value; a \emph{chamber cut} is the reflection $u\mapsto2a-1-u$ in one such coordinate. A \emph{star} (above) is a set of cross pairs sharing an endpoint; a \emph{spectator} is a tensor factor left unchanged. A \emph{chart} is one fixed half law whose $L^2$ space is used to state and prove operator bounds for several laws at a cut (\cref{rem:root-charts}); bounds proved in a chart are transported to the actual marginals by the lemmas named where they are used, so ``in the fixed half chart'' always means ``in $L^2$ of the fixed half law displayed there''. A \emph{cell} is one of the geometric prime intervals $[x_j,x_{j+1})$ above the explicit Chebyshev threshold $X_{\rm Ch}$ in the block-charge estimate (\cref{lem:record:block-charge}), inside which primes are grouped into blocks of a fixed number $n_j$ (not a group cell). A \emph{gate} or \emph{checked inequality} is one finite inequality verified in Appendix~D; a \emph{coupon} is one proved saving entering a single coefficient (in particular $m$), as defined in \cref{sec:variance}; a \emph{cap} is a certified spectral bound $-gp^{-1/2}I\preceq A_p\preceq(1+c^+/p)I$ for a named normalised cut operator $A_p$, with named constants $g$ and $c^+$. The adjective \emph{selected} means the Part~V construction, except in \cref{sec:scale-comparison,sec:comparison-proof} where a \emph{selected atom} is an atom of a structured energy and a \emph{selected law} is a law occurring in an expansion, as defined there; a \emph{selected diagonal} is $\operatorname{Diag}_\iota(m_\phi)$ for an eligible record $\phi$ (\cref{sec:variance}); \emph{native} means computed directly from the law in its own actual marginals, not obtained by a conversion such as repricing from $a_0$ or transport from a fixed half chart; \emph{final} means the construction of the closing under discussion---check whether baseline or improved parameters are in force; \emph{anchor} and \emph{evaluation exponent} both mean the smaller exponent $a_0$ at which a price was first computed. A \emph{ledger} is an explicit list of the records of one prime range together with their weights and prices, whether displayed in the text or stored in a named data file; the \emph{twelve-query ledger} is that list for the twelve queries $\mathcal E_{12}$, retained in the upper and tail ranges even though only six queries are used in the closing. The \emph{frame} has two defined uses: the \emph{frame data} of (CP0) in Part~III (the standing data of \cref{def:cp0}), and the \emph{middle frame} (\cref{def:record:frame}), the package consisting of $\mu$, its named records, the first stage $\lambda$ and its dominator $\Nbr$ on a middle block. Elsewhere ``frame'' is an informal word for the standing choices (slots, cuts, external index, exponents) within which an estimate is stated, and the display in the same paragraph always says which choices are meant. A \emph{tag} is one of the two record differences of the first stage in (CP2)(b), one for each folded matching type. A \emph{packet} occurs only in \cref{sec:density-upgrade}, where it means a set of atoms changed simultaneously. \emph{Index and kernel.} Each query carries an \emph{external index} $(b_e,s_e)$ (interval and residue); the \emph{coupled index} is $(b_e+1,s_e+r_e)$ with $r_e$ a random square class. \emph{Wrapping} is the case $b_e=K$, where $b_e+1$ wraps to the first interval and kernel cancellation fails; $W$ bounds the terms in which every active query wraps. The \emph{kernel estimate} (\cref{sec:kernel,app:kernel20}) is the statement that ordered pairs forced into a square class with no integer-square difference have negligible Fourier pairing. \emph{Closings.} $\Theta$ denotes the closing number for the stage being discussed: \eqref{eq:intro:closing} in the baseline and \eqref{eq:final-joint-closing} in the improved stage. The \emph{baseline closing} (\cref{sec:closing}) has $\theta=\vartheta=1$ and $\Theta<\PushTheta$; the \emph{improved closing} (\cref{sec:four-routes-closing}) has $\vartheta=\FourRoutesDensity>1$ and $\Theta<\FourRoutesTheta$ and uses an induction beyond Theorem~C, whose hypothesis (CP0) requires $0<\theta\le1$. Appendices~D and~E tabulate the baseline unless a caption states the improved closing. \subsection{Reading the proof}\label{subsec:intro:outline} The paper has six parts and six appendices. Part~I is this introduction, the one-query miniature in \cref{sec:mechanism} (\cref{prop:mech:one-query}), and the design explanation in \cref{sec:design-walk}. Part~II (\crefrange{sec:notation}{sec:scale-comparison}) proves the lower bound $Y\ge\alpha^{72}$, defines $Y$, proves the kernel estimate, and proves rescaling and the baseline induction. Part~III (\crefrange{sec:comparison-theorem}{sec:comparison-proof}) states and proves Theorem~C. Part~IV (\crefrange{sec:labellings}{sec:completion-repair}) proves the local estimates: counting labellings, cut operators, spectral bounds, second-order character sums, and how to make a graph law reflection positive. Part~V (\crefrange{sec:design}{sec:closing}) is the construction: it specifies the design, verifies the hypotheses of Theorem~C range by range, each section ending with the rows of \cref{tab:hypotheses} that it verifies, and evaluates the baseline $\Theta$ in \cref{sec:closing}; the middle range takes seven of its sections (\crefrange{sec:middle-reference}{sec:matching-mean}: blocks and spectral bounds for the twelve-label law, its nonnegative reweightings, the reference and first-stage laws with their domination, the comparison records, the variance savings, the dominating matrices, and the dominators for $\nu$ with the mean constant). The improved closing follows in \crefrange{sec:density:moments-prefix}{sec:four-routes-closing}. Part~VI (\cref{sec:history,sec:obstructions}), placed after the proof, explains how the construction developed and records obstructions and limits. The appendices contain the external inputs (\cref{app:external}), Peyre's theorem in finite form (\cref{app:peyre}), the kernel proof (\cref{app:kernel20}), the finite certificates (\cref{app:certificates}), the baseline data tables (\cref{app:data}), and the OpenAI exponent calculation (\cref{app:openai-constant}). The logical dependence is simple: Part~III uses Part~II, Part~V uses only the statements of Parts~II--IV, and Parts~I and~VI cite nothing as a premise. A reader who wants the logical skeleton can read \cref{sec:mechanism,sec:design-walk}, the statements of Part~II, \cref{sec:comparison-theorem}, \cref{tab:hypotheses}, \cref{sec:design} and \cref{sec:closing}, accepting the local estimates. A reader who wants to see where the quantitative work occurs should then read Part~IV and follow the prime ranges through \crefrange{sec:frontier:iidprefix}{sec:tail-index}. \space % End sections/01_introduction % Begin sections/02_mechanism \providecommand{\PushK}{890666} \providecommand{\PushTheta}{0.99999999997327} \section{The whole argument with one query} \label{sec:mechanism} \paragraph{What this section proves and how to read it.} This section proves nothing new; it assembles, with one query instead of six, the four facts on which the whole proof rests, in the form \cref{prop:mech:one-query}: at a least counterexample, $1\le\mathcal E+BR_I/2+W_1+o(1)$, where $W_1=BR_I/(2\Kint^{35/36})$ is the one-query wrapping term. The four facts are: (1) a reflection-positive law gives $\alpha^{72}\le Y$ for the $72$-fold Fourier average $Y$ (\cref{subsec:mech:chessboard}); (2) at a least counterexample every change of the law is bounded by its price times $Y$, because fixing labels restricts to shorter square-step progressions (\cref{subsec:mech:prices}); (3) small primes enter through an external index coupling the two ends of the query (\cref{subsec:mech:index}); (4) coupled terms in which the query is accepted and intervals do not wrap are negligible by the kernel estimate (\cref{subsec:mech:kernel}). Inputs: the definitions of Part~II, quoted by label. Output: the one-query inequality, whose six-query form is Theorem~C (\cref{thm:comparison}); Part~V applies it with six queries. A first reading should follow the statements and the sketch after \cref{prop:mech:one-query} and skip the quoted hypothesis checks; nothing here is a premise of a later section. \Cref{subsec:mech:budget} explains why one query cannot give $\Theta<1$, and \cref{subsec:mech:crude} why conditioning independent labels does not work, which motivates \cref{sec:design-walk}. \subsection{The \texorpdfstring{$72$}{72}-fold average and reflection positivity}\label{subsec:mech:chessboard} Let $N$ be large (in particular so large that the prime ranges below are nonempty as stated), let $A\subseteq[N]$ be square-difference-free, and let $\alpha=|A|/N$. The labels of the proof live in the finite group $G_N=\prod_p\Z/p^{e_p}\Z$, a product over three kinds of primes (\cref{def:record:functional}): the primes $p\equiv1\pmod4$ below $\Pfour=2^{512}$, with $e_p=2\mcl$ and $\mcl=8192$; the primes $p\equiv3\pmod4$ in $[Q_3,\Pfour)$, $Q_3=19951586$; and all primes in $[\Pfour,N^{1/20}]$, the last two kinds with $e_p=1$. The prime $2$ and the primes $p\equiv3\pmod4$ below $Q_3$ are not coordinates of $G_N$; they enter in \cref{subsec:mech:index}. The \emph{lift} of $A$ is \[ F_A(z)=\sum_{q(\xi)\le N^{1/20}}\widehat{\one_A}(\xi)\,e(z\cdot\xi), \qquad\widehat{\one_A}(\xi)=\frac1N\sum_{n\in A}e(-n\xi), \] the sum over the characters $\xi$ of $G_N$ whose conductor $q(\xi)$ is at most $N^{1/20}$. It is real, and its mean over the uniform law on $G_N$ is the coefficient of the trivial character: $\E F_A=\alpha$. \paragraph{Slots, cuts and reflection positivity.} Let $V$ be a finite set of \emph{slots}, $d=|V|$. For a finite signed measure $\kappa$ on the labellings $z=(z_v)_{v\in V}\in G_N^V$ and real functions $g_v$ on $G_N$ put \[ \Lambda_\kappa\bigl((g_v)_{v\in V}\bigr)=\int\prod_{v\in V}g_v(z_v)\,d\kappa(z), \qquad\Lambda_\kappa(g)=\Lambda_\kappa\bigl((g)_{v\in V}\bigr). \] The average of the proof is $Y=\Lambda_\mu(F_A)$ for one fixed probability measure $\mu$, the \emph{reference}. A \emph{cut} is a fixed-point-free involution $\vartheta$ of $V$ with a decomposition $V=V_+\sqcup V_-$, $V_-=\vartheta V_+$. The \emph{cut matrix} of $\kappa$ at $\vartheta$ is $C_\vartheta(\kappa)_{x,y}=\kappa(z_{V_+}=x,\ z_{\vartheta V_+}=y)$, indexed by $x,y\in G_N^{V_+}$, and its \emph{cut form} is $Q_\kappa(X,X')=\ip X{C_\vartheta(\kappa)X'}$ for \emph{half-functions} $X,X'\colon G_N^{V_+}\to\R$. If $X$ and $X'$ are products of functions of the single labels, $Q_\kappa(X,X')$ is the average $\Lambda_\kappa$ in which the factors of $X$ sit on $V_+$ and those of $X'$ are carried to $V_-$ by $\vartheta$ \eqref{eq:cc:bilinear}. The measure $\kappa$ is \emph{reflection positive} at $\vartheta$ if $C_\vartheta(\kappa)$ is symmetric and positive semidefinite (\cref{def:rp,def:cc:order}). Reflection positivity at a cut is preserved by sums, positive multiples and tensor products \eqref{eq:cc:kron}. \paragraph{One cut, and folding repeatedly until all slots agree.} Let $\phi_+$ be the map of $V$ that fixes $V_+$ and sends $v\in V_-$ to $\vartheta v$, and $\phi_-$ the map that fixes $V_-$ and sends $v\in V_+$ to $\vartheta v$. If $\kappa$ is reflection positive at $\vartheta$, the Cauchy--Schwarz inequality for its cut form gives, for every assignment $h\colon V\to\R^{G_N}$ of functions to slots (\cref{lem:holder:one-cut}), \begin{equation}\label{eq:mech:one-cut} \bigl|\Lambda_\kappa(h)\bigr|^2\le\Lambda_\kappa(h\circ\phi_+)\, \Lambda_\kappa(h\circ\phi_-),\qquad\Lambda_\kappa(h\circ\phi_\pm)\ge0, \end{equation} where $\Lambda_\kappa(h)=\Lambda_\kappa((h(v))_v)$: a mixed average is at most the geometric mean of the two averages in which one half has been copied onto the other. A sequence of cuts $\vartheta^1,\dots,\vartheta^T$ with signs $s_t\in\{\pm\}$ is \emph{sorting} if the composition $\phi^{\vartheta^T}_{s_T}\circ\dots\circ\phi^{\vartheta^1}_{s_1}$ of its folds is constant (\cref{def:sorting}). \begin{theorem*}[Signed H\"older inequality] If $\kappa$ is reflection positive at every cut of a sorting sequence, then for all real functions $g$, $g_v$ on $G_N$ \textup{(\cref{thm:holder})} \[ \Lambda_\kappa(g)\ge0\qquad\text{and}\qquad \bigl|\Lambda_\kappa\bigl((g_v)_{v\in V}\bigr)\bigr| \le\prod_{v\in V}\Lambda_\kappa(g_v)^{1/d}. \] \end{theorem*} \emph{Sketch.} Fix finitely many functions $f_1,\dots,f_k$, and let $M$ be the largest value of $|\Lambda_\kappa(h)|$ over the assignments $h$ with values in $\{f_i\}$. If $h$ attains $M$, both folded assignments $h\circ\phi_\pm$ again take values in $\{f_i\}$. By \eqref{eq:mech:one-cut} they are nonnegative, at most $M$, and their product is at least $M^2$, so both equal $M$: folds of maximizers are maximizers. Folding along the whole sorting sequence produces a constant maximizer, so $M=\max_i\Lambda_\kappa(f_i)$. Applied to $f_v=g_v/(\Lambda_\kappa(g_v)+\epsilon)^{1/d}$, $\epsilon>0$, multilinearity gives the inequality as $\epsilon\to0$. This is the chessboard estimate of statistical mechanics in finite form. Consequently $\|g\|_\kappa=\Lambda_\kappa(g)^{1/d}$ is a seminorm, and if every one-slot marginal of $\kappa$ is uniform, then $|\E g|\le\|g\|_\kappa$, by the inequality with $g$ at one slot and $1$ at the others (\cref{cor:seminorm}). With $g=F_A$ this is $\alpha^d\le\Lambda_\kappa(F_A)$. The inequality says more: every average of the same shape, with arbitrary real functions at the slots, is controlled by the diagonal averages of its inputs. This is what makes the prices of \cref{subsec:mech:prices} possible. \paragraph{The slot array.} The slots form $V=\Zsix\times\Zsix\times\{0,1\}$, $d=72$, with slots $(u_0,u_1,\ell)$ (\cref{def:slot-array}). On each chamber coordinate $\Zsix$ there are the chamber reflections $\vartheta_a(j)=2a-1-j$ with plus halves $H_a=\{a,a+1,a+2\}$, and $\vartheta_{c,a}$ is $\vartheta_a$ acting on $u_c$. The layer carries the reserved cut $\iota(u_0,u_1,\ell)=(u_0,u_1,1-\ell)$, with plus half $V_+=\{\ell=0\}$. The plus folds of $\vartheta_0$ and $\vartheta_4$ are $f_0=(0,1,2,2,1,0)$ and $f_4=(0,0,5,4,4,5)$ (values at $0,\dots,5$), and $f_0\circ f_4\circ f_0$ is constant. Folds of different coordinates commute, so the seven-step sequence $\vartheta_{0,0},\vartheta_{0,4},\vartheta_{0,0},\vartheta_{1,0},\vartheta_{1,4}, \vartheta_{1,0},\iota$, all with sign $+$, maps every slot to $(0,0,0)$ (\cref{lem:slot-array}(ii),(iii)). The family $\mathfrak F$ of the chamber cuts and $\iota$ consists of seven involutions. The reference is a product $\mu=\bigotimes_\Blk\mu_\Blk$ over the \emph{atoms} $\Blk$ of $G_N$ (the single primes of the prefix, blocks of the primes $p\equiv3\pmod4$ in $[Q_3,\Pfour)$, and the single tail primes) of probability measures that are reflection positive at every cut of $\mathfrak F$ and invariant under the maps $z_{v,p}\mapsto r_pz_{v,p}+t_p$, $r_p$ a square unit, chosen independently at each prime; in particular their one-slot marginals are uniform (\cref{hyp:record:reference}). Hence (\cref{lem:record:holder}) \begin{equation}\label{eq:mech:density} \alpha^{72}\le\Yf(\Lsc,A)=\Lambda_\mu(F_A)=Y . \end{equation} Positivity turns density into size; the proof shows, conversely, that $Y\le C\Lsc^{-a}\alpha$ at the scale $\Lsc$ in the decomposition $N=\Kint\Lsc$ of \cref{subsec:mech:prices} (the next subsection). \paragraph{The six distinguished slot pairs (queries).} The proof uses the six queries $e=(u_e,v_e)=((0,j,0),(2,\rot j,1))$, $j\in\Zsix$, of the family $\mathcal E_6$, where $\rot j=j+2$ for even $j$ and $\rot j=j-2$ for odd $j$. Their twelve endpoints are distinct, the sources lie in $V_+$, the targets in $V_-$, and the reflected targets $\iota v_e=(2,\rot j,0)$ in $V_+$ (\cref{lem:slot-array}(iv)). Each query crosses the reserved cut. In this section one query $e$ is enough. \subsection{Rescaling by square steps: the price of changing a local law}\label{subsec:mech:prices} \paragraph{The induction.} Write $N=\Kint\Lsc$ with a fixed integer $\Kint\ge2$ (in the baseline $\Kint=\PushK$; the improved stage uses $\Kint=\FourRoutesK$), and fix a price exponent $a$ with $0C_0\Lsc^{-a}\alpha$, while $\Yf(\Lsc',A')\le C_0(\Lsc')^{-a}\alpha_{A'}$ for every scale $\Lsc'<\Lsc$ and every square-difference-free $A'\subseteq[\Kint\Lsc']$, $\alpha_{A'}$ its density. Every argument of the proof takes place at such a pair, and its aim is a contradiction once $\Lsc$ is large. Throughout, $o(1)$ is a quantity that tends to zero as $\Lsc\to\infty$, uniformly in $A$. \paragraph{Fixing labels is rescaling.} Let $\Blk$ be an atom of primes with $e_p=1$, and $q_\Blk=\prod_{p\in\Blk}p$. Fixing, for one slot, its block label $z_\Blk\in X_\Blk=\prod_{p\in\Blk}\Fp$ fixes for that slot a residue class $\mathfrak a$ modulo $q_\Blk$ (the argument below is applied slot by slot through the signed H\"older inequality): by the Chinese remainder theorem the specialized lift $F_A(z_\Blk,\cdot)$ is, at every character $\xi$ of the other coordinates with $q(\xi)q_\Blk\le N^{1/20}$, the lift of $q_\Blk\one_{A\cap(\mathfrak a+q_\Blk\Z)}$ (\cref{lem:record:fibre-scale}(a)). Split the class into the $q_\Blk$ progressions with the square step $q_\Blk^2$. Since $q_\Blk^2k^2=(q_\Blk k)^2$, the set $A$ meets each progression $\{q_\Blk^2n'+c\}$ in a rescaled copy $A'_c=\{n':q_\Blk^2n'+c\in A\}$, which is again square-difference-free and lives at the scale $N/q_\Blk^2$. So, up to the characters of large conductor, whose contribution is an error linear in $\alpha$ (\cref{lem:record:density-dc}), $F_A(z_\Blk,\cdot)$ is an average of lifts of square-difference-free sets at a shorter scale, composed with square-affine maps, which preserve $\mu$ (\cref{lem:record:fibre-scale}(b),(c)). By the triangle inequality for the seminorm $\Lambda_\mu(\cdot)^{1/72}$ and the induction hypothesis at the shorter scale, the specialized input has $\Lambda_\mu$ at most $(1+o(1))(q_\Blk^2)^a(\alpha_{\rm f}/\alpha)Y$, $\alpha_{\rm f}$ the density of $A$ in the class; the average over the progressions introduces no further factor: by the triangle inequality for the seminorm $\Lambda_\mu(\cdot)^{1/72}$ its seminorm is at most the weighted average of the progression seminorms (the weights sum to one), and concavity of $t\mapsto t^{1/72}$ moves that average inside the power. A change of the law at $\Blk$ changes all $72$ slots, and the signed H\"older inequality multiplies the $72$ slot factors $(q_\Blk^2)^{a/72}$, while the fibre densities average to $\alpha$ under labels with uniform one-slot marginals. \paragraph{The price of a change: total variation times $q_{\Blk}^{2a}$.} The \emph{price} of a finite signed measure $\zeta$ on $X_\Blk^V$ is $\|\zeta\|_{\rm var}\,q_\Blk^{2a}$ (\cref{def:price}; at a prefix prime the factor is $p^{e_pa}$). The structured-energy estimate (\cref{prop:record:density-structured}) states that, at a least normalized counterexample, the \emph{energy} $\Lambda_{\zeta\otimes\mu_{-\Blk}}(F_A)$ of $\zeta$, in which the factor $\mu_\Blk$ of the reference is replaced by $\zeta$, has absolute value at most $(1+o(1))\|\zeta\|_{\rm var}\,q_\Blk^{2a}\,Y$, provided the variation of $\zeta$ has uniform one-slot marginals; changes at several atoms multiply their prices. Inputs restricted to intervals and residue classes are priced in the same way. An input that sees only an interval of length $\Lsc=N/\Kint$ and a residue class modulo an integer $D_0$ (the inputs $g^{I,D_0,s}$ of \cref{subsec:mech:index}) is a lift at a scale shorter by the factor $\Kint\sq(D_0)$, where $\sq(D_0)$ is the least square divisible by $D_0$ (for instance $\sq(24)=144$). Its slot costs $(\Kint\sq(D_0))^{a/72}$, and a fixed interval adds the factor $\Kint^{1/72}$, because the density of $A$ on an interval of length $N/\Kint$ is at most $\Kint\alpha$ (\cref{def:record:structured-energy}). The product of these factors is the \emph{coarse price} of the energy. \paragraph{The only use of the induction hypothesis.} Every comparison between laws in the proof is reduced to energies of this kind, and the induction hypothesis enters only through the rescaling above. Everything else is an exact identity at one scale, an estimate of a finite local law, or one of two analytic remainders: the cancellation of \cref{subsec:mech:kernel}, and the selections of atoms with a large product (\cref{lem:record:density-can,lem:record:density-lp}). Both remainders are $O(\Lsc^{-\sigma}\alpha)$, linear in the density. At a counterexample $Y>C_0\Lsc^{-a}\alpha$, so such a remainder is at most $(C/C_0)\Lsc^{a-\sigma}Y=o(1)Y$. This is why $a<\sigma$ is required, and why the induction can keep the full density factor $\alpha$ on the right: the density exponent $\theta=1$ of \cref{thm:record:lineardensity}. \subsection{One query and its external index \texorpdfstring{$(b,s)$}{(b,s)}}\label{subsec:mech:index} The prime $2$ and the primes $p\equiv3\pmod4$ below $Q_3$ form the fixed external modulus $\Mzero=2^{129}\prod_{3\le p0$. The complete proof is \cref{rem:cp:one-query}, which checks the hypotheses of the lemmas used in the frame of Part~III. \emph{Keeping the common mean.} Part~(a) of \cref{lem:record:common-mean} keeps exactly the component supported on no query and no conductor coordinate (the \emph{empty-support}, that is constant, component): that of $J_\nu$ is $Y_\nu$, and that of each energy is the mean energy $e_M=Q_M(\bar X,\bar X)$ of the bracket measure. It gives $J_\nu\le Y_\nu+(BR_I+o(1))Y-e_M$, and if $e_M\ge(m-o(1))Y$, the conclusion becomes \[ 1\le\tfrac12\mathcal E+\frac{BR_I}2+W_1+\frac{1-m}2+o(1): \] keeping the common mean halves the coefficient of $\mathcal E$, and a mean constant $m>1$ lowers the right-hand side further through $(1-m)/2$. This is the case $k=1$ of \cref{thm:comparison} without a first stage ($L_0=0$), with the one energy factor $B$ of (H2) in place of both $Be^T$ in $J$ and $Be^{S+A}$ in $W$. \begin{remark}[A positive comparison law]\label{rem:mech:positive} If every factor $\nu_\Blk$ were reflection positive at $\iota$, the bracket of (H2) would hold with $M_\Blk=\nu_\Blk$, since $\bigl(\begin{smallmatrix}C&C\\ C&C\end{smallmatrix}\bigr)= \bigl(\begin{smallmatrix}1&1\\ 1&1\end{smallmatrix}\bigr)\otimes C\succeq0$ for $C=C_\iota(\nu_\Blk)\succeq0$, and part (a) of the index-support lemma with $\mathcal T=T$ would be the plain coupling inequality $2Y_\nu-\bar V_\nu\le I_\nu$ of \cref{lem:hyb:coupling}, where $\bar V_\nu=\frac12(V_\nu(X)+V_\nu(Y))$ is a scalar (not the slot set $V$). The comparison laws of the construction accept the queries but are not reflection positive at $\iota$ (\cref{subsec:walk:bracket} explains why); the signed index form and the bracket are what replace positivity there. In the middle range the comparison laws are signed measures: a fold record of the comparison law is a signed combination of three nonnegative accepting laws with exact marginals (\cref{def:record:mixture}). The cancellation of \cref{subsec:mech:kernel} is applied to each nonnegative product component, and the variation of the signed laws multiplies only the constant of a vanishing remainder (\cref{def:cp4,lem:record:wrap-expansion}). The bracket asks less than positivity: $M$ has to dominate $\nu$ only at the one cut $\iota$, and it need not accept anything. \end{remark} \subsection{Why the sum of error bounds must be \texorpdfstring{$<1$}{<1}, and why one query fails} \label{subsec:mech:budget} \Cref{prop:mech:one-query} says that a least counterexample forces $\mathcal E+BR_I/2+W_1\ge1-o(1)$. Hence if $\mathcal E$ and $B$ do not depend on the scale and $\mathcal E+BR_I/2+W_1<1$, no least normalized counterexample exists at large scales; once every $o(1)$ is shown to come only from structured energies and the two analytic remainders (\cref{lem:record:rec}), the induction of \cref{thm:record:lineardensity} gives $s(N)\le CN^{1-a/71}$. Each term has a direct meaning. The left side is the constant coefficient $2$ of $2P-T$, divided by $2$: in \eqref{eq:mech:signed} the term without an active index is $2Y_\nu$, while the coupled form, in which the index is active, cancels by the kernel except for the wrap. The conductor moment $R_I\ge1$ is the price of revealing the index: the squared slot price of an input restricted to an interval and to the residues kept by the inclusion law, averaged over the inclusions. And $B$ is the energy factor of the bracket, the price of controlling by a positive measure a law that is not reflection positive at $\iota$; in the comparison theorem $B=e^{U_0}+R_{\rm err}\ge1$. With one query the coupled term $BR_I/2$ is at least $R_I/2$, about $0.623$ at the baseline $R_I$, so even with $B=1$ the comparison price $\mathcal E$ would have to be below about $0.377$; at the baseline energy factor $B<2.332628665480$ it is about $1.454>1$, so one query cannot give $\Theta<1$. Using $k$ queries with disjoint endpoints and independent indices, the operator $\bigotimes_e(2P_e-T_e)$ has constant coefficient $2^k$, while the energies factor over the queries, each contributing $R_I$ (\cref{lem:envelope-energy}). The coupled term becomes \[ J=Be^T\Bigl(\frac{R_I}2\Bigr)^k, \] where $T$ is the total price of the dominators for $\nu$ in (CP6) (\cref{def:cp6}). For $k=6$, $(R_I/2)^6<0.0588$ at the baseline $R_I$, and $J<0.25177$ at the baseline $B$ and $T<0.60760$ (baseline values; the improved values are in \cref{sec:four-routes-closing}). Why six queries are used, and why these six, is explained in \cref{subsec:walk:queries}. Theorem~C is \cref{prop:mech:one-query} for $k$ queries with two refinements: a first-stage law $\lambda$ with total price $L_0$ between $\mu$ and $\nu$, dominated at $\iota$ with energy factor $B$, against which the symmetric and skew parts of $\nu-\lambda$ are priced separately; and retention of the common mean, which lowers the coefficient of $L_0+\mathcal E$ to $1-2^{-k}$. Its comparison law may be, at a set of atoms whose number is bounded independently of the scale (the middle blocks), a real combination of nonnegative accepting laws (\cref{def:cp4}, \cref{rem:mech:positive}). It gives $1\le\Theta+o(1)$ with $\Theta=(1-2^{-k})(L_0+\mathcal E)+J+W+(1-m)/2^k$ at a least counterexample. Part~V constructs $\nu$ with baseline $\Theta<\PushTheta$ (\cref{sec:closing,tab:intro:values}); the improved value $\Theta<\FourRoutesTheta$ is proved later by the separate $\vartheta>1$ induction. \subsection{Why conditioning independent labels on a square difference does not work}\label{subsec:mech:crude} Which law should accept the query? The obvious candidate starts from the law $\mu_0$ of independent uniform labels, whose cut matrices have rank one and which is reflection positive at every cut, and conditions it on $z_{v_e}-z_{u_e}\in\Qsq$ at every prime $p$ of $G_N$ with $e_p=1$ (and on the corresponding event at the prefix primes). At one prime this replaces the uniform law of the pair $(z_{u_e},z_{v_e})$ by the uniform law on the strict-square pairs $\Om$. The uniform law puts the mass $(p+1)/(2p)$ outside $\Om$, and conditioning moves all of it onto $\Om$; so the change $\nu_p-\mu_{0,p}$ has total variation norm $\|\nu_p-\mu_{0,p}\|_{\rm var}=(p+1)/p>1$ (twice the moved mass), and its price exceeds $p^{2a}>1$. In the expansion of $\nu=\bigotimes_p(\mu_{0,p}+(\nu_p-\mu_{0,p}))$ the prices of the primes multiply, and their total grows with the number of primes of $G_N$: it is not bounded independently of the scale, so $\mathcal E$ cannot be bounded. Even a change of size about $1/p$ at every prime is too large, since $\sum_pp^{2a-1}$ over the primes of $G_N$ is unbounded. Two ingredients are missing. First, reference laws whose records already give a square difference on most of their mass, so that an accepting law changes only a small part at each prime. Second, a way to bound many primes jointly: a change on a whole block of primes should be bounded by about its worst prime, with one factor $q_{\Blk}^{2a}$ for the block. \Cref{sec:design-walk} explains both (\cref{subsec:walk:graph-laws,subsec:walk:completions} and \cref{subsec:walk:blocks} respectively). \paragraph{Consequences and what to read next.} This section quotes, by their labels, statements of Part~II (the square shift \cref{lem:square-shift}, \cref{sec:positivity}, the functional and the kernel of \cref{def:record:functional,prop:record:kernel20}, and \cref{sec:scale-comparison}) and of Part~III (\cref{sec:comparison-theorem,sec:comparison-lemmas,sec:comparison-proof}), the comparison law of the middle range (\cref{def:record:mixture}), and the final values of \cref{sec:closing}; its only new statement, \cref{prop:mech:one-query}, is proved in \cref{rem:cp:one-query}. \space % End sections/02_mechanism % Begin sections/03_design_walk \section{From the one-query argument to the full construction}\label{sec:design-walk} \paragraph{What this section proves and how to read it.} This section proves nothing and is not a premise of any later section. Its purpose is to explain, before the formal construction in Part~V, why each feature of that construction is needed. \Cref{sec:mechanism} reduced the theorem to: exhibit a signed law $\nu$ whose nonnegative summands accept six disjoint queries across $\iota$, dominate it at $\iota$ as in Part~III, and achieve $\Theta<1$. Each subsection below follows the same pattern: \emph{Problem} means ``with the naive choice just described, $\Theta\ge1$ (or no scale-independent bound exists), because [an explicit number]'', and \emph{Construction} describes the choice used in Part~V and names the section proving it. The numerical illustrations use the density-linear baseline of \cref{sec:closing}. The final theorem uses the additional moments, normalized assignments and joint mean allocation in \cref{sec:four-routes-closing}; \cref{subsec:walk:glance} connects these ingredients. Historical comparisons are collected in Part~VI. Every version of the argument has the same three tasks: verify finitely many local operator inequalities, sum the resulting prices over blocks of primes, and check $\Theta<1$. The subsections explain the local laws that make the first task possible with small constants, the block summation that makes the second finite, and the sharper inequalities that make the third true. The earlier $216$-slot construction used the same general tools. \Cref{tab:walk:substitutions} records the four structural changes; \cref{subsec:history:216} gives the historical instances and their certificates. Those instances are not premises of the present proof. \begin{table}[htbp] \centering \small \caption{The four structural substitutions.}\label{tab:walk:substitutions} \begin{tabular}{@{}>{\raggedright\arraybackslash}p{0.375\textwidth}% >{\raggedright\arraybackslash}p{0.45\textwidth}% >{\raggedright\arraybackslash}p{0.11\textwidth}@{}} \toprule $216$-slot design & final design & explained in\\ \midrule $V=(\Zsix)^3$, sorted by nine folds; the reserved cut is a chamber reflection of the third coordinate; exponent $a/(216-\theta)$ & $V=(\Zsix)^2\times\{0,1\}$, sorted by seven folds; the reserved cut is the layer flip $\iota$; exponent $a/(72-\theta)$ ($a/71$ at $\theta=1$) & \cref{subsec:walk:queries}\\ \addlinespace nine coupled families and a singleton recurrence, with the records that do not accept covered by obstruction cylinders; later one fixed family of sixteen (at one checkpoint four) amplified edges & six disjoint one-way queries with a common signed index; records that do not accept are repaired with their actual marginals, or deleted & \cref{subsec:walk:queries,subsec:walk:repair}\\ \addlinespace a comparison law that is reflection positive at the reserved cut & a comparison law that is a signed combination of nonnegative accepting laws, not reflection positive, controlled at $\iota$ by a reserved Gram bracket; symmetric and skew changes priced separately; signed whole-block fold records, variance and envelope credits, common mean & \cref{subsec:walk:bracket,subsec:walk:accounting}\\ \addlinespace the same laws for both classes of primes (a map law, two middle arrays, a three-depth high range); small primes in the index with generic bounds & class one: a square-clique prefix; class three: a twelve-label middle law and a two-layer $72$-slot upper law; small class-three primes in the index with the exact square-shift contraction & \cref{subsec:walk:blocks,subsec:walk:bracket,subsec:walk:analytic}\\ \bottomrule \end{tabular} \end{table} \subsection{Put square-difference constraints into the reference law (graph laws)}\label{subsec:walk:graph-laws} \paragraph{Problem.} The crude accepting law of \cref{subsec:mech:crude} starts from independent labels and conditions them on a square difference. At every prime its change has variation more than one, and the prices of the primes multiply. The reference knows nothing about squares, so the comparison law has to create every square relation by itself. \paragraph{Construction: graph laws.} The square relations are put into the reference. At a prime $p$ the labels are drawn from a \emph{graph law} $\lambda_p(G)$ (\cref{def:graphs:labeling}): the uniform law on the labellings of the vertices of a small oriented graph $G$ by distinct elements of $\Fp$ in which every edge $u\to w$ is a strict-square constraint, $z_w-z_u\in\Qsq$. The slots are labelled through maps from slots to vertices; the laws obtained in this way are the \emph{records} of \cref{subsec:walk:completions}. A record that maps a query to an edge of $G$ already forces that query at the prime and is kept unchanged, so it needs no replacement and contributes no replacement price. The middle law lives on twelve vertices, $\Zsix\times\{0,1\}$ (one chamber coordinate and the layer), with all four layer lifts of the six edges $u\to\rot u$: $24$ directed edges, every vertex of outdegree two and indegree two (four incident constraints), and the edge $(0,0)\to(2,1)$ onto which every query projects. The upper law lives on all $72$ slots, with $720$ directed edges and every vertex of outdegree ten and indegree ten (twenty incident constraints), and its root contains every query (\cref{subsec:push:layer12spectral}, \cref{lem:upper-geometry}). \paragraph{Why a graph law is almost independent.} The number of labels available to a vertex whose $t$ neighbours carry distinct labels is $p2^{-t}$, up to a relative error of order $2^tp^{-1/2}$, by Weil's bound (\cref{lem:extension}). Iterating this count gives every marginal, conditional law and density of $\lambda_p(G)$, relative to the independent law, with explicit relative errors of order $2^tr$, $r=p^{-1/2}$ (\cref{sec:labellings}); the relative form is what makes them usable at explicit thresholds (\cref{subsec:intro:new}). The law is invariant under the maps $z\mapsto sz+c$ with $s$ a nonzero square, so its one-slot marginals are uniform (\cref{lem:marginals}). The errors grow like $2^t$ with the number of constraints at a vertex, which is one reason why graphs of small degree are used where the primes are small: the twelve-label law from $Q_3=19\,951\,586$ on, the $72$-slot law only from $\Pthree=167\cdot2^{40}$ on (\cref{subsec:walk:blocks}). What remains is that a graph law is not reflection positive (\cref{subsec:walk:completions}), and that the records which do not map the queries to edges must be changed (\cref{subsec:walk:repair}). \subsection{Graph laws are not reflection positive: adding correction summands} \label{subsec:walk:completions} \paragraph{Problem.} At a chamber cut the two halves of a graph law are coupled through its cross edges. Relative to the product of its half laws, its normalized cut operator is a combination of character kernels such as $\chi(y-x)$, each of normalized size about $p^{-1/2}$, and its spectrum reaches down to about $-gr$, for a constant $g$ of the graph (\cref{sec:cuts}). So $\lambda_p(G)$ is not reflection positive, and the signed H\"older inequality (\cref{thm:holder}) does not apply to it. \paragraph{Construction: the five-type completion.} The root law (type L, weight $1$) is completed by records built from the laws of its half graphs and composed with maps of the chamber coordinate onto parts of itself: three folds (type D), two matchings (S), six merges (R) and two constants (C), with the graded weights $1$, $w_{\rm D}r$, $w_{\rm S}r$, $w_{\rm R}r^2$, $w_{\rm C}r^3$ (\cref{lem:five-type}). Positivity at a chamber cut is built in steps of one order in $r$ each. The aligned fold is a copy of the half law placed symmetrically; it is fixed samplewise by the cut, and it supplies the positive diagonal that cancels the negative part $-dr$ of the root if $w_{\rm D}\ge d$ (here $d,f,h$ are the spectral constants of \cref{lem:five-type}; this $d$ is not the slot count $d=72$). A fold that is aligned at one cut is not aligned at the others, where it couples two corners of the half; the matchings pay for this if $w_{\rm S}\ge w_{\rm D}$. The row errors $fr$, $hr$ of the folds and matchings are paid by the merges if $w_{\rm R}\ge fw_{\rm D}+hw_{\rm S}$, and the linear terms of the merges by the constants if $w_{\rm C}w_{\rm S}\ge w_{\rm R}^2$; the constants, of weight $r^3$, together with the matchings, of weight $r$, dominate the $r^2$ cross terms of the merges in the Schur complement at the cut, since the product of the $r^3$ and $r$ weights has the same $r$-order as the square of the $r^2$ merge weight. The chamber group transports positivity from one chamber cut to all of them (\cref{lem:slot-array}(i)), and one-layer copies of the completion records, placed on the reserved diagonal, restore positivity at $\iota$. (The history of this completion, through an earlier version on $216$ slots, is in \cref{sec:history}.) The twelve-label reference of the middle range (thirteen inequalities per piece, together with the inequality that protects the $2\times2$ block at $\iota$, \cref{lem:front12:reference}) and the $25$-state two-layer reference of the upper range ($105$ inequalities per band, \cref{lem:upper-reference-rp}) are its two instances in the construction. \paragraph{Reweighting the principal law by a nonnegative function.} The root itself need not be the graph law. Reweighting it at every prime by a nonnegative weight built from trace scores---the average $\frac13\sum_j(1+\ulaw\Hs j)^2$ of the individual squares for the three opposite base pairs, or $1/100+(1+\ulaw H_{\mathcal D_{39}})^2$ for the coherent dictionary of $39$ traces---keeps its accepting support, its symmetries and its uniform one-slot marginals, and lowers the constant $d$ of its chamber cut below $\sqrt{30}$ (\cref{def:positive-root,lem:positive-root-properties,lem:imp:coherent39-law,cert:positive-root-caps}). The price is a larger constant $k_{\rm L}$ of the layer cut, paid through the weight $v_{\rm L}$ of the one-layer copy (\cref{prop:root-layer}), and a changed half marginal, paid in the restorations of the variance credits and of the mean savings (\cref{lem:record:root-marginal}(iv)). Both cut bounds are proved in the fixed half charts in which the completion inequalities are stated (\cref{rem:root-charts}). The gain is only in the negative part of the chamber-cut operator. Indeed, every law satisfying the sixteen cross constraints of that cut, with the half marginal and chamber symmetries of the graph law, has centred norm --- the operator norm on half-functions of mean zero in the stated half marginal --- at least about $\sqrt{30}\,r$: with those marginals no improvement is possible. A nonnegative reweighting, however, changes the half marginal, and can thereby raise the least eigenvalue (\cref{subsec:obs:root}). The construction tilts the root on the seven pieces from $2^{30}$: averages of individual squares on six of them, and on the final piece the coherent $39$-trace square with the constant $1/100$ added. Sharper collision bounds on two explicit subspaces, an interpolation between the two pair bounds, and a layer remainder summed without expanding all its monomials make these parameter values work (\cref{sec:positive-roots}). \paragraph{Inputs.} The constants $d$, $f$, $h$ are spectral caps and row bounds of graph laws (for $d$ on the seven last middle pieces, of the positive roots). The spectral criterion certifies at one prime that the normalized cut operator of a graph law has spectrum in $[-gp^{-1/2},1+O(p^{-1})]$, by a character expansion of its kernel, an extraction of witnesses (\cref{lem:matching:extractionk}) and a Schur test; monotone majorants carry the bound to all larger primes (\cref{lem:majorant}). It has two routes: Route~A, through conditional laws of the opposite half (\cref{thm:spectral-criterion}), and, at the root of the upper law below $2^{52}$, Route~B, a direct decomposition into explicit uniform averages over allowed sets (\cref{thm:record:direct-star}). At the chamber cut of the uniform middle root, complete actual stars give the cap directly: the eighteen star features of the root have an exact signed star matrix of norm $\sqrt{30}$, and a translation-sector completion, a rectangular factorization of the root and balanced collisions bring the cap at $Q_3$ below $5.500058$ (\cref{subsec:middle-l20}). The row bounds come from pinned influence, through Kassabov's and Peyre's inequalities (\cref{prop:middle-negative}), and from density ratios (\cref{lem:record:class-three,lem:row-comparison}). \paragraph{Why second-order character sums are needed.} On a block of primes (\cref{subsec:walk:blocks}) the negative side of a cut operator is governed by the worst prime, but the positive side multiplies over the primes: if the factors have spectra in $[-g_p,1+b_p]$, with $0\le g_p\le1+b_p$ and $b_p\ge0$, the tensor product has spectrum in \[ \Bigl[-\max_pg_p\prod_{q\ne p}(1+b_q),\ \prod_p(1+b_p)\Bigr] \] (\cref{lem:spec:tensorcomp}). The density ratios of the conditional rows --- the conditional distributions of one half given the labels of the other half, in the row notation of \cref{sec:spectral} --- multiply over the block in the same way. These quantities must therefore be of order $1/p$, and a first-order bound, such as Weil's bound for one character, of order $p^{-1/2}$, is not enough for them. In the $216$-slot design the first-order bound for a row of its middle completion would have given a bound of about $35$ for the logarithm of the product of the row factors over its first middle piece, where the second-order bound gave $4.3\cdot10^{-3}$ for the same logarithm. In the final design some of the second-order quantities follow from exact counts at the primes $p\equiv3\pmod4$: the density ratios of the middle rows lie between $R_2^{-1}$ and $R_2=(p-3)(p-7)/((p-11)(p-15))=1+O(1/p)$, and between $R_1^{-1}$ and $R_1=(p-1)/(p-3)$ for one layer (\cref{lem:record:class-three}). The others need genuinely second-order estimates (\cref{sec:dl}; \cref{subsec:intro:deligne} says where each enters): the four-cycle kernel, bounded through the character table of $\mathrm{GL}_2(\Fp)$ and Jacobi sums (\cref{thm:dl:K}); character sums in two variables and second moments of trace functions with a moving root $\lambda$ (not the principal law), bounded through Deligne's theorem and the Katz--Sarnak description of a family of curves (\cref{thm:dl:H2,lem:moving-root-moments}); and, for the second moment of the neighbourhood count behind the half variances of the root, a twisted second moment of Legendre traces, evaluated through a cusp form of weight four (\cref{thm:ahlgren-ono,lem:record:weighted-moment}). \subsection{Summing a price at every prime is too large: group primes into blocks}\label{subsec:walk:blocks} \paragraph{Problem.} With graph laws and repairs (\cref{subsec:walk:repair}) the comparison law changes a record of weight of order $r$ by a measure of norm of order $r$, so the change at one prime costs about $c/p$, for a local constant $c$, and is priced $(c/p)\,p^{2a}$. The sum $c\sum_pp^{2a-1}$ over all primes is unbounded (\cref{subsec:mech:crude}), and on a finite range it is large: over the primes $p\equiv3\pmod4$ of $[Q_3,\Pthree)$ the sum $\sum_p1/p$ alone is about $0.33$, while the local constants of the middle records are of order ten (twice a completion weight $w_{\rm D}$ between $5.43$ and $5.51$, times a norm coefficient of order one). \paragraph{Construction: blocks.} Consecutive primes are grouped into blocks $\Blk$ with $\log q_\Blk\le L$, $q_\Blk=\prod_{p\in\Blk}p$ (\cref{subsec:record:middle_blocks}), and each block carries one law: the completion, with $r=b_\Blk^{-1/2}$ for the least prime $b_\Blk$ of $\Blk$, of the tensor product over its primes of the graph laws (for the root on the seven last middle pieces, of their positive tilts). A tensor product of operators that preserve the constants decomposes into exact-support sectors (\cref{lem:sector}). On a sector with one active prime, the difference of two tensor products is the difference at that prime; on a sector with several active primes it is a product of small factors. So a change made jointly at all primes of a block costs about as much as at its worst prime, $c/b_\Blk$, and its price is $c\,b_\Blk^{-1}q_\Blk^{2a}\le c\,e^{2aL}/b_\Blk$: one selection factor $e^{2aL}$ for the whole block. The negative spectrum of a block is likewise that of its worst prime, times a product $\prod_{p\in\Blk}(1+O(p^{-1}))$ that stays bounded (\cref{subsec:walk:completions}). \paragraph{Choosing the block-size bound $L$.} Near $x$ about $L/\log x$ primes $p\equiv3\pmod4$ fit into one block, so about $dx/(2L)$ blocks start in $[x,x+dx]$, and heuristically \[ \sum_{\Blk}\frac c{b_\Blk}\,q_\Blk^{2a}\approx c\,\frac{e^{2aL}}{2L}\,\log\frac{\Pthree}{Q_3}. \] The factor $e^{2aL}/L$ is least at $L=1/(2a)$, where the total is about $c\,a\,e\log(\Pthree/Q_3)$ and grows linearly with $a$. Hence $a$ is limited by the local constants $c$: every price grows with $a$ through $q_\Blk^{2a}$, and $a$ can be raised only by lowering a local constant. At the baseline parameters $e^{2aL}\log(\Pthree/Q_3)/(2L)$ is about $0.039$, against about $0.33$ for single primes. The construction uses $L=570$, close to $1/(2a)\approx562.8$ (\cref{def:record:exact-blocks}); although every block satisfies $\log q_\Blk\le L$, the local laws are verified at the slightly larger bound $L_{\rm loc}=585$, hence with the prime-count cap $\lfloor L_{\rm loc}/\log X\rfloor$, so they hold on every block (\cref{lem:record:local-domain}). Middle prices computed at the evaluation exponent $a_0=\PushAnchor$ are converted to $a$ by $t=e^{2(a-a_0)L}\approx1.000000062$ (\cref{lem:record:repricing}). Blocks are formed from exact prime counts below an explicit threshold and from fixed-size prime-counting intervals above it, controlled by \cref{thm:bmor}. \paragraph{The ranges.} A block is priced with the local constants of its least prime, so different laws are used where different constants are smallest (\cref{tab:ranges}). Below $Q_3$ the primes $p\equiv3\pmod4$ are not coordinates of the labels but enter the index of the queries, each at a factor close to one in the conductor moment $R_I$ (\cref{subsec:walk:analytic}). In $[Q_3,\Pthree)$ the twelve-label law needs one added edge in each nonaccepting record of degree one, so its changes are of order $r^2=1/p$ per prime. From $\Pthree=167\cdot2^{40}$ on, the two-layer law on all $72$ slots contains every query in its root, every one of its records of degree at most one accepts. Repairs start at degree two and deletions at degree three, so its operator prices at one prime are of order $r^3=p^{-3/2}$ (\cref{sec:frontier:upper-oneway}); the Route~B criterion supplies its root caps from $\Pthree$ to $2^{52}$, with graded root counts and coefficients interpolated between certified prime thresholds, and the Route~A criterion those from $2^{52}$ on (\cref{subsec:upper-bands}). From $\Pfour=2^{512}$ on, the primes of both classes are single atoms with a fixed two-layer tail law, at prices $O(p^{-3/2+2a})$ with a convergent sum (\cref{sec:tail-index}). The primes $p\equiv1\pmod4$ below $2^{512}$ need no comparison at first order (\cref{subsec:walk:bracket}). \subsection{One query leaves an error term above \texorpdfstring{$1$}{1}: use six disjoint queries} \label{subsec:walk:queries} \paragraph{Problem.} With one query the coupled term $BR_I/2$ of \cref{prop:mech:one-query} is about $1.45$ at the baseline values, already above $1$ before any comparison price is added (\cref{subsec:mech:budget}). \paragraph{Construction: six disjoint queries.} With $k$ disjoint queries and independent indices the matching term is $Be^T(R_I/2)^k$ (\cref{subsec:mech:budget}, \cref{thm:comparison}). But every retained record of the comparison law must accept every query, and acceptance costs added constraints. The geometry of $V$ decides how many queries are cheap. The six queries $e_j=((0,j,0),(2,\rot j,1))$, $j\in\Zsix$, of \cref{def:slot-array} all have the first-coordinate pair $(0,\rot0)=(0,2)$; they differ only in the second chamber coordinate, on which they act by $\rot$. The middle laws ignore that coordinate (\cref{lem:slot-array}(v)), so they see one query, the edge from the label $(0,0)$ to the label $(2,1)$, and each nonaccepting fold or matching record of the middle law needs one added edge; the prefix law ignores the layer as well and sees one coincidence event (\cref{subsec:front6:construction}). Six is the largest number of disjoint queries with this projection, since there are only six slots $(0,j,0)$. So six queries cost the middle range no more than one, while the matching term carries $(R_I/2)^6<0.0588$; finally $J<0.25177$. The larger family of twelve queries $((u,j,0),(\rot u,\rot j,1))$, $u\in\{0,5\}$, has two first-coordinate pairs, $(0,2)$ and $(5,3)$, and each nonaccepting fold or matching record then needs two added edges instead of one. The construction was first proved for these twelve queries and then specialized to the six, and only the six-query form was certified (row~8 of \cref{tab:history:checkpoints}). The twelve queries survive as the acceptance set of the middle merge repairs, of the one-way repairs and the dense EL comparison of the upper range, and of the tail, while the signed fold records of the middle, the LE mixture and the retained records $G_{01}L$, $G_{10}L$ of the upper range accept the six queries only (\cref{subsec:front12:construction,lem:six-query-retention}). Twelve queries would need more than new edges: joint laws (couplings) of the two halves forcing both queries of a fold record do exist, but with the unchanged references the symmetric error of the fold record is then of order $r$, at least about $r/\sqrt3$, and that of a matching fork at least about $\sqrt3\,r$ in symmetric plus skew norm (\cref{subsec:obs:twelve}). \paragraph{Why $216$ slots became $72$.} In the $216$-slot design the laws of the lower ranges ignored the third chamber coordinate: its only role there was to carry the reserved cut. A two-point layer with one reflection serves as well. The folds $f_0\circ f_4\circ f_0$ in each of two chamber coordinates, followed by the one fold of the layer, map $V=(\Zsix)^2\times\{0,1\}$ to a single slot (\cref{lem:slot-array}(iii)), so the chessboard estimate gives $\alpha^{72}\le Y$. Since the exponent of the theorem is $a/(|V|-\theta)$ (\cref{thm:comparison}), the same price exponent $a$ gives about three times the saving: $a/(216-\theta)$ becomes $a/(72-\theta)$, and the density-linear induction (\cref{subsec:walk:analytic}) then gives $a/71$. The laws of the high range, which used the third coordinate in the $216$-slot design (a hierarchy of three depths), became two-layer laws on the $72$ slots. The first $72$-slot design, which also treated the two classes of primes separately, raised the exponent from $2.288\cdot10^{-7}$ to $1.992\cdot10^{-6}$. \subsection{Records that do not force a square difference: replace, delete, or dominate them} \label{subsec:walk:repair} \paragraph{Problem.} The reference law is a positive combination of records. Most of its mass already forces the queries (in the middle range, the principal law and the aligned fold). Some records do not: in the middle range the other two fold records $F_1,F_2$ and the two matching records $E_0,E_1$ (degree one), and the merges and constants; in the upper range some records of degree at least two. Bounding a non-forcing record by its whole mass (a union bound over obstructions) charges order $r$ for a degree-one record, which is first order and too large: summed over primes it cannot give $\Theta<1$ (see \cref{subsec:obs:polynomials} for the abandoned union-bound polynomials, which play no logical role). Each non-forcing record must instead be removed by domination, replaced at fixed marginals, or deleted, according to its type. \paragraph{Construction: polarization and replacement at fixed marginals.} Both are proved in \cref{sec:completion-repair}. \emph{Polarization} (\cref{lem:tr:polarization}): at a chamber cut the two nonaligned fold records are dominated, in the cut order, by the two matching records plus a merge correction of one more order in $r$, so they can be removed without losing positivity at that cut. This is an order of cut matrices, not of measures; only actual records are subtracted, so the law stays nonnegative. \emph{Additive repair} (\cref{lem:tr:repair}): a record whose graph lacks the query edge is replaced by the graph law with the edge added, reweighted by a factor $1+f(x)+g(y)$ so that its half marginals at the cut are exactly those of the old record. The reweighting keeps the support, hence every constraint, and $f,g$ solve two linear equations that are well conditioned when the conditional operator of the new record is a contraction. The new and the old record then have the same actual half marginals, so their difference annihilates the constants on both sides of the cut; its energy is controlled by its operator norm between the actual half spaces, which is of order $r$, not by its mass. A record of weight of order $r$ costs $O(r)\cdot O(r)=O(1/p)$. Records of high degree are simply deleted and charged by their mass. The copies of records that the completion places on the reserved diagonal are handled by a \emph{first stage}: polarization at the chamber cut $\vartheta_0$ removes their nonaccepting fold records, and a one-stage repair keeps the actual conditional marginals of their matchings (\cref{lem:record:first-stage}, \cref{sec:middle-frame}); its loss, with the errors of the two folded matching repairs tensored at their own first cuts (\cref{cor:two-cut-series}), is $L_0<4.7634\cdot10^{-4}$. \paragraph{Replacements that keep the old cross edges.} A one-way repair builds its new record from two half copies and the projected queries and discards the old cross graph, so that a degree-two record whose old cross graph is large changes by a kernel of the size of that whole graph. For such records the upper comparison keeps the old cross graph, adds the missing required edges, softens the unrequired old edges that meet them, and repairs the result to the exact old actual marginals. Written in one common list of actual star feature functions, the old and the new star matrices then nearly cancel, and the difference is priced separately in its symmetric and skew parts. For the six LE records four such softened laws, each repaired to the same marginals, are mixed; the star matrix of the mixture is the mixture of their matrices, and at the selected weights its norm is below that of every component (\cref{def:dense-comparison,prop:dense-comparison,prop:le-mixture}). At $2^{48}$ the symmetric and skew operator norms in the actual half marginals are about $1.84r$ and $1.83r$ per LE record and $3.20r$ and $2.31r$ per EL record, against about $9.2r$ per LE record and $9.7r$ per EL record, charged in full to both prices, for one-way repairs of the same records at $2^{49}$ in the construction of row~11 of \cref{tab:history:checkpoints}. \subsection{The forcing law is not reflection positive: domination by \texorpdfstring{$2\times2$}{2 x 2} blocks} \label{subsec:walk:bracket} \paragraph{Problem.} In the $216$-slot design the middle laws and all their changes depended only on the first two chamber coordinates, so every nonnegative law built from them was fixed samplewise by the reserved cut, and a nonnegative measure fixed samplewise by a cut is positive there (\cref{lem:commoncut}(i)): the comparison law stayed reflection positive at the reserved cut. The final middle law carries the layer: its twelve labels are a chamber coordinate times the layer, and its query edge runs from layer $0$ to layer $1$. So $\iota$ acts on its labels, and a change of a record is, at $\iota$, a signed measure that is not positive. In the first $72$-slot design the upper laws already carried the layer, and positivity at $\iota$ was kept by adding to each repair a positive diagonal of the size of its change, the one-sided bracket of \cref{subsec:history:layers}; this diagonal was paid at first order. \paragraph{Construction: domination at the reserved cut, with symmetric and skew parts bounded separately.} The comparison law $\nu$ need not be positive at any cut, and on the middle blocks it is not even nonnegative: there it is a finite signed combination of nonnegative laws that accept the queries (\cref{def:cp4}). It is compared with the first stage $\lambda$ at $\iota$ alone, through a nonnegative measure $\Nbr$ with $\bigl(\begin{smallmatrix}\Nbr&\lambda\\ \lambda&\Nbr\end{smallmatrix}\bigr) \succeq_\iota0$, that is $-\Nbr\preceq_\iota\lambda\preceq_\iota\Nbr$ (\cref{lem:record:gram}); its energy factor is $B=e^{U_0}+R_{\rm err}<2.33263$ (\cref{lem:bracket-energy}). Every change $\nu_\Blk-\lambda_\Blk$ is split into its symmetric and skew parts at $\iota$, and each part is priced with its own positive envelope (\cref{def:cp4}). A nonzero skew part is never positive semidefinite, since a cut matrix that is $\succeq0$ is symmetric; keeping $\nu$ positive at $\iota$ means adding positive mass of the size of the change, which is what the first $72$-slot design paid. But a skew part costs nothing at first order. In the expansion of $Y_\nu-Y_\lambda$ over the blocks, every term with an odd number of skew factors vanishes, because both halves carry the same half-function and $\lambda$ is symmetric at $\iota$ (\cref{lem:record:record-expansion}). The reserved cost is therefore $B(e^S\cosh A-1)$: the symmetric price $S$ enters linearly, the skew price $A$ only through $\cosh A-1\approx A^2/2$. A comparison law that is positive at $\iota$ is its own bracket (\cref{rem:mech:positive}); the positive correction of the first $72$-slot design is that case. \paragraph{Signed combinations over a whole block of primes.} So the first-order change of an accepting record should be skew. Write $x_i$ and $y_i$ for the labels of the object $i$ of a two-layer fold record on the layers $0$ and $1$. At $p\equiv3\pmod4$ the number $-1$ is a nonsquare, so the reserved reflection, which exchanges $x$ and $y$, maps the channel $\mathsf C=\chi(y_0-x_1)$ of the added accepting edge $x_1\to y_0$ to $-\mathsf D$, where $\mathsf D=\chi(y_1-x_0)$ is the channel of its mirror $x_0\to y_1$. Writing $K_{\rm old}$ for the cut kernel of the reference fold record at $\iota$, relative to the product of its two actual half laws, adding both edges multiplies this kernel by $(1+\mathsf C)(1+\mathsf D)$, so the change of kernel is \[ K_{\rm old}(1+\mathsf C)(1+\mathsf D)-K_{\rm old} =K_{\rm old}(\mathsf C+\mathsf D)+K_{\rm old}\mathsf C\mathsf D: \] the first-order part $\mathsf C+\mathsf D$ is skew, and the symmetric part $\mathsf C\mathsf D$ is the kernel of the two disjoint cross pairs $(x_1,y_0)$ and $(x_0,y_1)$, spanning only two of the four pairs of $\{x_0,x_1\}\times\{y_0,y_1\}$ (a nonstar two-edge kernel), of normalized norm $O(1/p)$; the other orientation, $(1+\mathsf C)(1-\mathsf D)$, would make the first-order change symmetric; this is not the mirror pairing of \cref{lem:mirror}, which is the $(1+\mathsf C)(1+\mathsf D)$ orientation above. Within nonnegative combinations of the accepting sign patterns a zero symmetric leading error forces this pairing, with skew leading norm $\sqrt2\,r$. The fold record of the construction allows signed weights: it is the signed mixture \[ \bigotimes_{p\in\Blk}P_{++,p}+\frac\tlaw2\bigotimes_{p\in\Blk}P_{-+,p} -\frac\tlaw2\bigotimes_{p\in\Blk}P_{--,p}, \] taken after the products over the primes of the block, of three nonnegative accepting laws, each repaired to the actual half marginal of the reference record by an accepting Markov coupling (\cref{def:record:mixture,lem:signed-components}). Its symmetric leading change is still zero, its skew leading change is a three-arm star of norm about $\sqrt{1+\tlaw^2+(1-\tlaw)^2}\,r=1.2732\,r$ at $\tlaw=127/500$, and its variation $1+\tlaw$ does not grow with the number of primes. In the complete sign model a zero symmetric leading error forces a one-parameter family with this skew norm, least at $\tlaw=1/2$, whose laws have variation at least $1+\tlaw$ for $\tlaw\ge0$; the three-component law attains this variation, and the complete closing chooses $\tlaw=127/500$ (\cref{rem:obs:sign-frontier}). The comparison theorem allows such a law, because the cancellation of the kernel is applied to each nonnegative product component and the variation multiplies only the constant of a vanishing remainder (\cref{def:cp4}). Mirror pairing is the case $\tlaw=0$. The even products of skew changes, which survive in $\cosh A$, are not positive semidefinite either; positive envelopes in the algebra generated by the features depending on a single label (the singleton features), averaged over the reflections of the slot array in the first chamber coordinate, price them well below the coefficient $B$ that norm envelopes would give (\cref{thm:envelopes,lem:oct24:mask-schur,lem:reflection-averaging}). \paragraph{Including one fold diagonal in the dominating law.} The bracket carries one copy of the fold diagonal, $\Nbr=\lambda+F_{\rm fold}+H$ (\cref{lem:record:gram}), where $F_{\rm fold}$ is the sum of the two one-layer fold copies, $H$ is the analogous diagonal copy of the two-layer matchings, $E_{\rm add}$ below is a further pair of one-layer matching copies, $G$ is the polarization correction (two merge records), and $\Nbrz=\mu+E_{\rm add}+G+H$ is the auxiliary dominator of \cref{def:record:frame}. Then the part $\Nbrz-\mu$ of the bracket beyond the reference is invariant under the chamber group of the first coordinate except for the polarization correction $G$, a pair of merge records, and the envelopes use the invariant part as the positive background measure; its assigned price falls short of $U_0$ by only about $2.4\cdot10^{-5}$ (\cref{lem:oct24:invariant-background}). The price is a doubled protection of the fold records in the completion, $v_{\rm D}\ge2w_{\rm D}k_{\rm D}$ (\cref{lem:front12:reference}(iv)), which raises the prices of the first stage. It is affordable because the first-stage error is a series in the two first-stage record differences (the tags of (CP2)(b)), each tag being the difference whose largest cut norm is attained at its own cut, whose sharp bounds multiply there: $R_{\rm err}<2.0445\cdot10^{-4}$ and $L_0<4.7634\cdot10^{-4}$, against about $3.3\cdot10^{-3}$ and $7.6\cdot10^{-3}$ with one sharp factor per term (\cref{cor:two-cut-series}). \paragraph{The two residue classes modulo $4$.} At $p\equiv1\pmod4$ the strict-square relation is symmetric. Labels drawn conditionally independently from a random square clique of $\Z/p^{2\mcl}\Z$ (any two of its elements differ by an even power of $p$ times a unit square) give a reference that is reflection positive at every cut, since a chamber cut form is the square of a conditional mean, and that accepts every query unless its two labels coincide (\cref{lem:frontier:iidlocal}). This event has probability $2^{-\mcl}$ and is deleted, at a total price below $8\cdot10^{-69}$ (\cref{lem:frontier:iidenergy}); so these primes cost nothing at first order, and they leave the small modulus. At $p\equiv3\pmod4$ the relation is the Paley tournament, so a law that draws the two ends of a query exchangeably cannot accept it: these primes need the oriented graph laws and the bracket above, and the completion uses that the two-label middle law is uniform on distinct pairs, which holds at $p\equiv3\pmod4$ and fails at $p=13$ (\cref{rem:middle-class-three}). So the laws that the $216$-slot design used for both classes became a square-clique prefix below $2^{512}$ for class one and the middle and upper laws for class three (\cref{sec:frontier:iidprefix,subsec:obs:class-one}). Class three also gives exact identities used throughout: the density ratios of the rows, the Paley identities $\mathsf C^*=-\mathsf C$, $\mathsf C\mathsf C^*=pI-\Jall$ of the channels of the fold records (\cref{lem:square-shift}(c)), and the exact contraction of the index (\cref{subsec:walk:analytic}). \subsection{The crude bound exceeds \texorpdfstring{$1$}{1}: five sharper inequalities} \label{subsec:walk:accounting} \paragraph{Problem.} Bounding every simultaneous change by its norm, without sharper family bounds, without retaining the common mean, and with $T=S+A$, gives only the crude sufficient condition \[ L_0+B\bigl(e^S\cosh A-1\bigr)+Be^{S+A}\Bigl(\frac{R_I}2\Bigr)^6+W<1, \] which is a different (stronger) requirement than $\Theta<1$: it has no factor $63/64$, no savings $D$, and no mean term. At the baseline values its left-hand side is about $1.603>1$ (\cref{rem:record:plain}), so this crude route cannot prove the theorem. Five separate sharper inequalities below replace it by $\Theta<1$. \paragraph{Construction: five sharper inequalities.} Each credit below bounds a separately named term or coefficient in the closing quantities, and the five terms are distinct, so the five savings may be added without subtracting any quantity twice. \begin{enumerate}[label=(\alph*)] \item \emph{Variance credits} (\cref{sec:variance}). A repaired record has the actual half marginals of the record it replaces, so their difference annihilates the constants, and its form against the bracket is a variance: the energy of the diagonal copy at $\iota$ of its actual half marginal minus that of the product of its actual half marginals. Lower bounds for the latter, with positive backgrounds of the outside bracket, for one to four blocks and for the late pieces jointly, are subtracted from the reserved cost; finally $D_{\rm var}>0.0099585$. \item \emph{Positive joint envelopes} (\cref{thm:envelopes,cor:envelope-costs}). The even skew products are priced below their trivial coefficient $B$: by positive matrices built from the single-label and star feature functions and averaged over the reflections of the slot array. The part invariant under all reflections is priced separately at a smaller price, since an error depending on one changed coordinate can first be averaged over its orbit under the reflections; leading and remainder prices are kept apart. With (a) they form the discount $D>0.46685$, and $\mathcal E=B(e^S\cosh A-1)-D<0.76897$, against about $1.2358$ before the discount, of which about $1.2016$ is the even skew part. \item \emph{Bounding old and new records jointly} (the direct Gram matrix, \cref{subsec:record:direct_gram}). The matching envelopes of the fold records are built from a joint $2\times2$ Gram estimate of the old and the new record at $\iota$, instead of their norm envelopes. For the signed law its ideal coefficient is about $2.3842$ ($\sqrt6$ for pure pairing); each diagonal side coefficient of the joint Gram bound is the larger of the signed coefficient and a certified auxiliary coefficient bound for that side, and only its excess over the fold diagonal $v_{\rm D}$ that the bracket already carries is paid (\cref{prop:signed-sides}). The matching exponent is $T<0.60760$ instead of $S+A\approx0.984$, and $J<0.25177$ instead of about $0.3668$. At the October~18 design this step alone took the closing from $1.1219$ to $1.0122$. \item \emph{The common mean} (\cref{lem:record:common-mean}(a)). The component of empty support of the six signed indices is kept exactly, so the reserved cost is counted $63$ times out of the $64$ copies of the constant term: the coefficient of $L_0+\mathcal E$ is $63/64$. It saves about $0.0120$. \item \emph{The mean credit} (\cref{prop:record:mean-credit}). Positive means of records of the reference, and of the chosen side diagonals that the (CP6) matching dominators already include, at degrees up to four and on the late pieces jointly, give $m>1.58994$ in the term $(1-m)/64$, which saves about $0.0092$. \end{enumerate} The result is \[ \Theta=\tfrac{63}{64}\bigl(L_0+\mathcal E\bigr)+J+W+\tfrac{1-m}{64} \approx0.757418+0.251761+0.000038-0.009218, \] certified as $\Theta<\PushTheta$ (\cref{sec:closing}). Without (d) and (e) it would be about $1.0212$: in the baseline every listed credit is needed, and the margin $1-\Theta$ is about $2.7\cdot10^{-11}$. Every credit is an exact relation minus upper bounds for the same quantities (\cref{def:cp8}); an upper bound is never used as a lower bound, and a certified joint bound is never replaced by a sum of looser ones (\cref{subsec:obs:pitfalls}). \subsection{Six parameters of the analytic stage and the estimates they control}\label{subsec:walk:analytic} Six further parameters, from the analytic stage rather than the local laws, were also tightened; each removes a loss that would otherwise cost the final exponent. \paragraph{The density exponent $\theta=1$.} The induction bounds $Y$ by $C\Lsc^{-a}\alpha^\theta$, and the exponent of the theorem is $a/(72-\theta)$. The analytic remainders of the cancellation and of the large products were first bounded absolutely, by $C\Lsc^{-\sigma}$; against $Y>C_0\Lsc^{-a}\alpha^\theta$ this needs $\alpha$ not too small, which forced $\theta<1$ and a sparse side condition $as/(s-\theta)<\sigma$, with $s<1$ the exponent of a bound for sparse sets. In the six-query design of exponent $7.057\cdot10^{-6}$, with $\theta=29/50$, this condition was within one per cent of binding. Moment bounds that are linear in the density make every remainder $O(\Lsc^{-\sigma}\alpha)$ (\cref{lem:record:density-can,lem:record:density-lp}), so the induction keeps $\theta=1$ under the single condition $a<\sigma$ (\cref{thm:record:lineardensity}); the baseline $a\approx8.884\cdot10^{-4}$ is below $\sigma=1/825\approx1.212\cdot10^{-3}$, and all analytic side conditions hold on the whole range $0\sigma$; summing the raw errors over the small selections in the improved induction uses the additional $\tau$ allowance in (S1), as proved in \cref{prop:density:production}. The actual-square kernel for Fourier cutoffs up to $N^{1/20}$ and prime-power moduli (\cref{app:kernel20}) allows $\sigma=1/825$; the prime powers are needed by the square-clique prefix. \paragraph{The least square step.} Fixing the labels at a set of atoms fixes a residue class modulo an integer $D$, which is split into progressions whose step must be a square divisible by $D$. The step is the least such square, $\sq(D)$ \eqref{eq:square-step}, where the earlier versions used the square of the index part of $D$. The single-level law therefore improved the step for its always-revealed modulus $24$ from $576$ to $144$. The selected finite-depth law instead averages $\sq(\prod_p p^{J_p})$ over its conductor depths, with the same least-square principle at every level (\cref{prop:imp:padic-price}). \paragraph{A fixed number of intervals.} Earlier versions took $\Kint=2^{64}$ intervals, making the wrap negligible. Every proof holds for arbitrary fixed $\Kint\ge2$ (\cref{rem:fixed-parameters}). The matching term grows like $\Kint^{a/6}$, whereas the wrap decreases with $\Kint$. The selected fixed value $\Kint=\PushK$ gives $W<3.8345\cdot10^{-5}$. Feasibility at this integer is all the proof requires; the convexity calculation in \cref{rem:index-convexity} guides its choice. \paragraph{Square shifts at every conductor depth.} At the first odd-prime level the exact square-shift contraction is $\sqrt{p+1}/(p-1)$, optimal among doubly stochastic matrices on the strict-square transitions (\cref{lem:square-shift}(b)). This single-level optimality does not rule out a better distribution across conductor depths. The selected law conditions a uniform root to have valuation less than $m$ in each prime-power coordinate, and then squares it. Its depth envelopes and finite moment are proved in \cref{lem:imp:padic-envelope,prop:imp:padic-price}; the certified value is $R_I<1.247139907407$ at the baseline exponent. The selected final closing uses $R_I<1.252937308029$ (\cref{sec:four-routes-closing}). The old prime-moment certificate remains an auxiliary majorant for this evaluation. \paragraph{The digit pairs of the prefix.} The square clique uses $\mcl=8192$ digit pairs. Its exception is priced below $2^{513-\mcl+1024\mcl a}$ (\cref{lem:frontier:iidenergy}); with the earlier $\mcl=2048$ this bound would exceed one as soon as $a>1535/2^{21}$, that is $\eps>1.0309\cdot10^{-5}$, below the final exponent. With $8192$ pairs the bound stays below the allowance $10^{-12}$ on the whole analytic range $a\le9/10000$ (\cref{rem:record:prefix-walls}). \subsection{From the local laws to the final closing}\label{subsec:walk:glance} The examples above explain the baseline prices. The same local interfaces support the main theorem, but its final assembly must recompute their assignments together. \Cref{tab:walk:glance} gives the reading path; the baseline numerical table is \cref{tab:closing-values}, and the selected numerical ledger is in \cref{sec:four-routes-closing}. \begin{table}[htbp] \centering\small \caption{The construction's interfaces and their final assembly.} \label{tab:walk:glance} \begin{tabular}{@{}>{\raggedright\arraybackslash}p{0.43\textwidth}% >{\raggedright\arraybackslash}p{0.52\textwidth}@{}} \toprule Output & Proof and use\\ \midrule $\alpha^{72}\le Y$ & Reflection positivity, \cref{sec:positivity}\\ First-stage price $L_0$, dominator $B$ & Middle reference and frame, \cref{sec:middle-reference,sec:positive-roots,sec:middle-frame}\\ Comparison prices $S,A$ & Middle and upper accepting laws, \cref{sec:middle-records,sec:upper-comparison}\\ Discount $D$ & Fixed-marginal variance and positive envelopes, \cref{sec:variance,sec:envelopes}\\ Matching price $T$ and joint mean & Chosen sides and disjoint mean allocations, \cref{sec:matching-mean,subsec:joint-mean}\\ Conductor moment $R_I$ & Finite index law and summable tail, \cref{sec:tail-index}\\ $Y\le C\Lsc^{-a}\alpha^\vartheta$ & Prefix moments and density induction, \cref{sec:density:moments-prefix,sec:density-upgrade}\\ $\Theta<1$ & Normalized, compatible prices and the joint scalar, \cref{sec:four-routes-closing}\\ \bottomrule \end{tabular} \end{table} Each arrow from a local improvement to this closing requires its actual marginals, completion weights, restoration bounds and normalizing factors. A smaller isolated operator constant does not by itself lower $\Theta$. The final assembly keeps those dependencies explicit and evaluates every affected term at the selected parameters. \space % End sections/03_design_walk % Begin sections/04_notation \section{Preliminary lemmas: character sums, correlation, and monotone bounds}\label{sec:notation} \paragraph{What this section proves and how to read it.} This section proves no part of the main argument. It fixes conventions for finite probability spaces and operators, lists arithmetic notation, and states five inputs used as black boxes later: Weil's bound with Gauss and Jacobi evaluations (first-order $O(p^{-1/2})$ estimates), the spectrum of the square shift on $\mathbf F_p$, an explicit prime-counting bound, two correlation inequalities, and a method for extending a bound proved at the smallest prime of a range to every larger prime (monotone majorants). Inputs: only standard character-sum and probability facts, with Peyre's inequality proved in \cref{app:peyre}. Outputs: the lemmas cited by Parts~IV and~V for counting, correlation after fixing labels, and prime summation. A first reading should note the conventions in \cref{subsec:notation:conventions} and the statements only; proofs can be skipped. The list in \cref{subsec:notation:symbols} is an \emph{index of symbols} with pointers to defining sections, not a set of definitions; project terms are defined in \cref{subsec:intro:glossary} and at their formal sites. In particular ``price'' is defined in \cref{def:price}, not here. \subsection{Finite probability spaces, operators, and correlation}\label{subsec:notation:conventions} All probability spaces in the paper are finite. This subsection fixes expectation, norms, operator order and correlation once, so that later sections can use them without repeating conventions. Asymptotic notation is the standard one, made precise as follows: $X\ll Y$, $X=O(Y)$ and $X\lesssim Y$ all mean $|X|\le CY$ for an absolute constant $C$, independent of $N$, of the scale $\Lsc$, of $A$ and of $p$, unless a dependence is stated in the same statement or in the standing conventions of its section; $X\asymp Y$ means both $X\ll Y$ and $Y\ll X$; and $o(1)$ denotes a quantity tending to $0$ as $\Lsc\to\infty$ with all other parameters fixed, unless another limit is named. In statements at a least counterexample, $o(1)$ is this limit along counterexamples with $\Lsc\to\infty$. \begin{definition}[Finite probability spaces and operator order]\label{def:prelim:operators} For a finite probability space $(X,\mu)$, $\mathbb E_\mu f=\sum_{x\in X}\mu(x)f(x)$ and $\|f\|_{L^r(\mu)}=(\mathbb E_\mu|f|^r)^{1/r}$ for $1\le r<\infty$. The inner product is $\langle f,g\rangle_\mu=\mathbb E_\mu\overline f g$; $L^2_0(\mu)$ is the subspace of mean-zero functions. All unqualified averages on finite sets use uniform probability. A measure $\nu$ has density $h$ with respect to $\mu$ if $\nu(x)=h(x)\mu(x)$ at each point; its mass is $\nu(X)$. The notation $\delta_x$ denotes the probability measure concentrated at $x$. For a self-adjoint operator $T$, the notation $T\succeq0$ means $\langle f,Tf\rangle\ge0$ for every $f$. We write $S\preceq T$ if $T-S\succeq0$; this is the \emph{Loewner order}. The operator norm is $\|T\|=\sup_{\|f\|_2=1}\|Tf\|_2$. For a numerical matrix, the operator norm uses the ordinary Euclidean norms on its coordinate spaces: matrix multiplication is a sum, with no probability normalization. In particular, this convention applies to the matrix of correlation bounds in \cref{thm:peyre-finite}. A \emph{Markov operator} preserves nonnegative functions and the constant function $1$. \end{definition} \paragraph{Kernels, projections and centred norms.} Probability spaces are finite and, after the points of mass zero are discarded, have full support. For such a space $(\Omega,\lambda)$, $\Jproj f=\ip{\one}{f}_\lambda\one=(\E_\lambda f)\one$ and $P_0=I-\Jproj$ (in Part~IV also written $Q$; this $Q$ is not the conductor cutoff $Q$ of \cref{sec:lifts}) are the orthogonal projections onto the constants and onto $L^2_0(\lambda)$. For finite probability spaces $(X,\mu)$, $(Y,\nu)$ and a kernel $K\colon X\times Y\to\C$ let $T_Kf(x)=\int K(x,y)f(y)\,d\nu(y)$, and let $\opnorm K$ be the norm of $T_K$ from $L^2(\nu)$ to $L^2(\mu)$. Both spaces carry the uniform probability unless another measure is indicated; for the uniform probabilities, $\opnorm K$ is the operator norm of the entry matrix of $K$ (Euclidean norms) divided by $\sqrt{|X||Y|}$. If $X=Y$, $\mu=\nu$ and $K(y,x)=\overline{K(x,y)}$, then $T_K$ is self-adjoint. The all-ones kernel is $\Jall$, so that $T_{\Jall}=\Jproj$ on a uniform space; as a matrix acting on vectors indexed by $n$ points, $\Jall v=(\sum_yv(y))\one=n\Jproj v$. Let $T$ be a Markov operator from functions on $Y$ to functions on $X$ with $T\one=\one$ and $T^*\one=\one$, the adjoint taken with respect to $\mu$ and $\nu$. Equivalently, $Tf(x)=\E_\pi[f(y)\mid x]$ for the coupling $\pi(x,y)=\mu(x)T(x,y)$ of $\mu$ and $\nu$, $T(x,y)$ being the transition probability, so that $Tf(x)=\sum_{y\in Y}T(x,y)f(y)$; we call $T$ the operator of the coupling. As $\ip{\one}{Tf}_\mu=\ip{T^*\one}{f}_\nu$, $T$ maps $L^2_0(\nu)$ into $L^2_0(\mu)$, and its \emph{centred norm} is $\|T|_{L^2_0(\nu)}\|=\|T-\Jproj\|$, with $\Jproj f=(\E_\nu f)\one$. By \cref{def:prelim:maxcorr} the centred norm of the operator of a coupling is the maximal correlation of its two coordinates. For a cut $c$ of a slot array, $\kappa\succeq_c\kappa'$ means that the cut matrix of $\kappa-\kappa'$ is symmetric and positive semidefinite (\cref{def:cc:order}). \begin{definition}[Mean, fluctuation and compression]\label{def:split:notation} On a finite probability space $(\Omega,\lambda)$ with full support let $\Jproj f=(\E_\lambda f)\one$ and $P_0=I-\Jproj$. For a real function $U$ put $u=\E_\lambda U$, $U^\circ=P_0U$ and $\sigma_U=\norm{U^\circ}_2$. Thus $\norm U_2^2=u^2+\sigma_U^2$. For an operator $T$ on $L^2(\lambda)$ with $\ip\one{T\one}=1$, its two \emph{marginal errors} are $c=T\one-\one$ and $b=T^*\one-\one$; its \emph{mean-zero compression} is $C=P_0TP_0$. Relative to the constants and their orthogonal complement, \[ T=\begin{pmatrix}1&b^*\\c&C\end{pmatrix}, \] where $b^*$ is the functional $g\mapsto\ip bg$ on $L^2_0(\lambda)$. \end{definition} Both marginal errors are mean-zero, since $\ip\one c=\ip\one{T\one}-1=0=\ip{T^*\one}\one-1=\ip b\one$, and for $f=\alpha\one+f_0$ with $f_0\in L^2_0(\lambda)$, $Tf=(\alpha+\ip b{f_0})\one+(\alpha c+Cf_0)$, which is the block form. The operator of a coupling of $\lambda$ with itself has $b=c=0$ and centred norm $\|C\|$. The completion inequalities of \cref{lem:five-type} are written in this notation. \begin{definition}[Maximal and conditional maximal correlation]\label{def:prelim:maxcorr} For random variables $X,Y$ on a finite probability space, the \emph{maximal correlation} is \[ \rho(X;Y)=\sup\big\{|\E f(X)g(Y)|:\ \E f(X)=\E g(Y)=0,\ \E f(X)^2=\E g(Y)^2=1\big\}, \] with $\rho=0$ if either side has no non-constant functions. The intersection of the spaces $L^2(X)$ and $L^2(Y)$ of functions of $X$ and of $Y$, inside $L^2$ of the underlying space, contains the constants. If it consists of the constants only, then $\rho(X;Y)$ is the Friedrichs cosine of these two subspaces (the supremum of $|\langle f,g\rangle|$ over unit vectors $f$ in one subspace and $g$ in the other, after the constants are removed); if it is larger, then $\rho(X;Y)=1$, while the Friedrichs cosine may be smaller. In all cases $\rho(X;Y)$ is the norm of the conditional expectation operator $L^2_0(X)\to L^2_0(Y)$. For a family $(X_i)_{i\in I}$ and $S\subseteq I$, the \emph{conditional} maximal correlation of $X_i,X_j$ given $X_S=s$ is the maximal correlation computed under $\Pr(\cdot\mid X_S=s)$, for every value $s$ of positive probability. \end{definition} \begin{definition}[Friedrichs angle]\label{def:prelim:angle} For closed subspaces $V,W$ of a finite-dimensional Hilbert space, the \emph{cosine of the Friedrichs angle} is $\cos\angle(V,W)=\sup\{|\ip vw|:\ v\in V,\ w\in W,\ \norm v=\norm w=1,\ v,w\perp V\cap W\}$. It is $0$ if one space contains the other. \end{definition} \subsection{Arithmetic notation, square classes, and index of symbols}\label{subsec:notation:symbols} \paragraph{Arithmetic notation.} Throughout, $p$ denotes a prime, $q=1/p$ and $r=p^{-1/2}$; for odd $p$, $\chi=\chi_p$ is the quadratic character. We write $[N]=\{1,\dots,N\}$ and $\ee t=e^{2\pi it}$. All logarithms are natural, an empty product is $1$, and a positive integer is \emph{squarefree} if no square of a prime divides it. For a positive integer $d$ we write $v_p(d)$ for the exponent of $p$ in $d$, $\varphi(d)$ for the number of invertible residues modulo $d$, $\omega(d)$ for the number of its distinct prime divisors (always with its argument) and $\rad(d)$ for their product; $\pi(x)$ is the number of primes up to $x$. For $\xi\in\Q/\Z$, $q(\xi)$ is its reduced denominator, the \emph{conductor}, with $q(0)=1$; for a set $U$ of primes, $q_U=\prod_{p\in U}p$. For an odd prime $p$ we put \[ \Qsq=\{u^2:u\in\Fp^\times\},\qquad \Ap(t)=\one_{\Qsq}(t),\qquad \Om=\{(x,y)\in\Fp^2:\ y-x\in\Qsq\}; \] $\chi_p(t)$ is $1$ on nonzero squares, $-1$ on non-squares and $0$ at $t=0$, and $G_p(k)=\sum_{u\in\Fp}\ee{ku^2/p}$. The space $L^2(\Fp)$ carries the uniform probability, $\ip fg=\E_{a\in\Fp}\overline{f(a)}g(a)$, and $e_k(a)=\ee{ka/p}$, $k\in\Fp$, is an orthonormal basis; the $e_k$ with $k\ne0$ span $L^2_0(\Fp)$. For a law $\nu$ on a finite set and functions $F$ and $G$ on that set, $\norm F_\nu^2=\E_\nu|F|^2$ and $\ip FG_\nu=\E_\nu\overline FG$; the index is dropped when the law is clear. \begin{definition}[Strict square classes]\label{def:strict-square-class} Let $D=8d$ with $d$ odd, not necessarily squarefree. A residue $r\bmod D$ is a \emph{strict square class} if $r\equiv1\pmod8$ and $r$ is a nonzero square modulo every prime dividing $d$. \end{definition} By Hensel's lemma the second condition is equivalent to $r$ being the square of a unit modulo every odd prime power dividing $D$: if $p$ is odd, $p\nmid r$ and $c_j^2\equiv r\pmod{p^j}$, then $c_{j+1}=c_j+tp^j$ with $2c_jt\equiv(r-c_j^2)/p^j\pmod p$ satisfies $c_{j+1}^2\equiv r\pmod{p^{j+1}}$, and $t$ exists because $p\nmid2c_j$. Every unit modulo $8$ has square $1$, so by the Chinese remainder theorem the strict square classes modulo $D$ are exactly the squares of units modulo $D$; in particular a strict square class is a unit modulo $D$. The external index of \cref{def:hyb:coupled} also uses nonunit squares at a fixed prime-power modulus. We use the following more general class only when explicitly stated. \begin{definition}[Nonvanishing square classes]\label{def:nonvanishing-square-class} Let $D=2^{h_2}\prod_{p\text{ odd}}p^{h_p}$ with $h_2\ge3$. A residue $r\bmod D$ is a nonvanishing square class if, at each odd $p\mid D$, it has valuation $2j_p{\raggedright\arraybackslash}p{0.22\textwidth}% >{\raggedright\arraybackslash}p{0.74\textwidth}@{}} \caption{Principal symbols. Numerical illustrations are at the baseline parameters unless the selected parameters are specified.}\label{tab:notation}\\ \toprule symbol & meaning (and where it is defined)\\ \midrule \endfirsthead \toprule symbol & meaning (and where it is defined)\\ \midrule \endhead \bottomrule \endfoot $N$, $[N]$, $s(N)$ & the scale of the main theorem; $\{1,\dots,N\}$; the largest size of a subset of $[N]$ with no nonzero square difference\\ $A$, $\alpha$ & a square-difference-free set $A\subseteq[N]$ and its density $\alpha=|A|/N$; the letter $A$ alone is also the skew total (row $S$, $A$, $T$)\\ $\epsilon$ & the exponent of the main theorem, $s(N)\le CN^{1-\epsilon}$, $\eps=a/(72-\theta)=\FourRoutesExponent$; the baseline has $\eps=a/71=\PushExponent$\\ $a$, $a_0$, $a_{\rm u}$ & the price exponent of the functional, baseline $a=\PushA$, selected $a=\FourRoutesA$; the anchor $a_0=\PushAnchor$, at which the middle prices are certified (\cref{subsec:closing-quantities}); the upper ledger has its own anchor $a_{\rm u}=883/10^6$ (\cref{prop:record:upper})\\ $\theta$ & the density exponent of the induction: baseline $1$, selected $\FourRoutesDensity$ (also denoted $\vartheta$ in the closing); chamber reflections carry their cut indices, and $\theta(x;4,r)$ always carries its arguments\\ $\Lsc$, $\Kint$ & the interval scale, $N=\Kint\Lsc$; the number of intervals of the index: baseline $\Kint=\PushK$, selected $\Kint=\FourRoutesK$\\ $L$, $L_{\rm loc}$, $L_{\rm band}$, $L_{\rm u}$ & the actual block budget $L=570$ of the middle range (\cref{def:record:exact-blocks}), used for the repricing and for the caps in the restorations of \cref{lem:record:restoration}; the local cap $L_{\rm loc}=585$, at which the local laws, the block densities, the row constants, the spectral caps and $k_{\rm D}$, $k_{\rm new}$ are evaluated at every piece start (\cref{lem:record:local-domain}); the budget $L_{\rm band}$ of an upper band, an integer between $550$ and $886$ at which the local data of the band are evaluated (\cref{def:record:upper-bands}); and the block length $L_{\rm u}=50000/27$ of the local data of the tail datum, larger than every band budget (\cref{def:record:parameters})\\ $G_N$, $e_p$ & the label group $\prod_p\Z/p^{e_p}\Z$ over the set $\mathcal P_N$ of primes of the scale $N$, with $e_p=2\mcl$ at the primes $p\equiv1\ (4)$ below $\Pfour$ and $e_p=1$ otherwise (\cref{def:record:functional})\\ $V$, $d$ & the slot array $(\Z/6\Z)^2\times\{0,1\}$ with slots $(u_0,u_1,\ell)$, $d=|V|=72$; the layer coordinate is $\ell$ (\cref{def:slot-array})\\ $\rot$ & the rotation of $\Z/6\Z$: $\rot j=j+2$ for even $j$ and $\rot j=j-2$ for odd $j$\\ $\vartheta_{c,a}$, $H_a$ & the chamber reflection $\vartheta_a(j)=2a-1-j$ in the coordinate $c\in\{0,1\}$, with plus half $H_a=\{a,a+1,a+2\}$\\ $\iota$ & the reserved cut $(u_0,u_1,\ell)\mapsto(u_0,u_1,1-\ell)$, with plus half $\{\ell=0\}$; $\iota$ is used for nothing else, and the class indicator is written $\one_{p\equiv1\,(4)}$\\ $\mathcal E_6$, $e=(u_e,v_e)$ & the six queries $u_e=(0,j,0)$, $v_e=(\rot0,\rot j,1)$, $j\in\Z/6\Z$ (\cref{def:slot-array})\\ $p$, $q$, $r$; $\chi$, $\Qsq$, $\Om$ & a prime, $q=1/p$, $r=p^{-1/2}$; the quadratic character, the nonzero squares, the strict-square pairs\\ $G_p(k)$, $G_\chi$, $\eps_G$, $\Jac$ & Gauss sums, $G_\chi^2=\chi(-1)p$, $\eps_G=G_\chi/\sqrt p$ (\cref{thm:gauss}); the Jacobi sum (\cref{thm:jacobi})\\ $\delta_{p,j}$; $\delta_p$, $\delta_j$ & the conductor-depth tail $\Pr(J_{e,p}\ge j)$ of \cref{def:hyb:coupled}, with the selected $m=64$ law of \cref{lem:imp:padic-envelope}; the latter two symbols are inclusion probabilities in the whole-coordinate special case\\ $\omega_e=(b_e,s_e)$ & the index of the query $e$: an interval and a residue modulo $\Mzero$ (\cref{def:hyb:coupled}); count errors are written $e_t$, $w_\Delta$, never $\omega$\\ $\Mzero$, $D_\Jc$, $\sq(d)$ & the external modulus $2^{129}\prod_{p3$. (c) The row sums $\sum_y\chi(y-x)$ and the column sums vanish, so $C\one=C^*\one=0$. The adjoint has entries $C^*(x,y)=\overline{C(y,x)}=\chi(x-y)=\chi(-1)C(x,y)$. The $(x,z)$ entry of $CC^*$ is $\sum_y\chi(y-x)\chi(y-z)$, which is $p-1$ for $x=z$ and $-1$ for $x\ne z$ by \eqref{eq:two-root}; so $CC^*=pI-\Jall$, and $C^*C=\chi(-1)C^2=CC^*$. On the constants $CC^*$ vanishes and on their orthogonal complement it is $pI$, so $\|C\|^2=p$. As a matrix acting on vectors, $P$ is $C/p$, and the uniform probability multiplies every inner product by the same factor $1/p$, so the adjoint of $P$ is $C^*/p$. Hence $P^*=\chi(-1)P$, $P^*P=C^*C/p^2=(pI-\Jall)/p^2=q(I-\Jproj)$ (as $\Jall/p=\Jproj$ on vectors), $PP^*=P^*P$ and $\|P\|=\|C\|/p=r$. Finally $2\Ap(y-x)=1+\chi(y-x)-\one_{y=x}$ for all $x,y$: both sides are $2$ if $y-x\in\Qsq$ and $0$ otherwise. So $T_p=\frac2{p-1}(\Ap(y-x))_{x,y}=(\Jall-I+C)/(p-1)$; applied to $f$ this is $(p\E f-f+pPf)/(p-1)$. (d) The map $(x,u)\mapsto(x,x+u)$ is a bijection of $\Fp\times\Qsq$ onto $\Om$. So under $\pi_{\mathcal S}$ the pair $(x,y)$ is $(x,x+u)$, with $x$ uniform on $X_{\mathcal S}$ and $u=(u_p)_p$ independent of $x$, its coordinates independent and uniform on the sets $\Qsq$. Hence $\int g_1(x)g_2(y)\,d\pi_{\mathcal S}=\E_xg_1(x)(T_{\mathcal S}g_2)(x)$ with $T_{\mathcal S}=\bigotimes_{p\in\mathcal S}T_p$. Expand $g_2(y)=\sum_\xi\widehat{g_2}(\xi)\ee{y\xi}$. The character $\ee{\cdot\,\xi}$ is the tensor product of the characters $e_{a_p}$ of the factors, so by (a) $T_{\mathcal S}\ee{\cdot\,\xi}=g(\xi)\ee{\cdot\,\xi}$ with $g(\xi)=\prod_{a_p\ne0}(G_p(a_p)-1)/(p-1)$; and $\E_xg_1(x)\ee{x\xi}=\widehat{g_1}(-\xi)$. This is the identity. By the computation in (a), $(G_p(a)-1)/(p-1)=\frac1{p-1}\sum_{m\in\Fp^\times}\ee{am^2/p}$. By the Chinese remainder theorem, $m\bmod q(\xi)$ runs over the units exactly when $(m\bmod p)_{p\mid q(\xi)}$ runs over $\prod_p\Fp^\times$, and $\ee{\xi m^2}=\prod_p\ee{a_pm^2/p}$; this gives the second expression for $g(\xi)$. By (a) each factor has modulus at most $1/(\sqrt p-1)$, and for $p\ge64$, $\sqrt p-1=p^{1/3}(p^{1/6}-p^{-1/3})\ge p^{1/3}(2-\tfrac14)\ge p^{1/3}$. Multiply over $p\mid q(\xi)$. \end{proof} The optimality in (b) concerns this specified class of transitions, the doubly stochastic kernels supported on square shifts; it places no restriction on a different construction of the indices. The index law uses (b), the Paley channels of the local laws use (c) (\cref{lem:paley-triple}), the pinned pair bounds (bounds with prescribed labels fixed) use the second statement of (a) (\cref{lem:mid:pinpair}), and the cancellation uses (d). \subsection{Primes in the classes modulo four}\label{subsec:notation:primes} For primes in a residue class modulo four we use the following explicit Chebyshev estimate. Write $\theta(x;4,r)=\sum_{p\le x,\ p\equiv r\ (4)}\log p$. \begin{theorem}[Bennett--Martin--O'Bryant--Rechnitzer {\cite[Theorem~1.2 and Table~1]{BMOR18}}]\label{thm:bmor} For $r\in\{1,3\}$ and every real $x\ge4\,800\,162\,889$, \[ \Bigl|\theta(x;4,r)-\frac x2\Bigr|0$, \begin{equation}\label{eq:peyre:hyp} \rho(X_i;X_j\mid X_S=s)\le\eps_{ij}. \end{equation} Then \begin{equation}\label{eq:peyre:concl} \rho\big((X_a)_{a\in A};(X_b)_{b\in B}\big)\le\min\{1,\opnorm{\mathcal E}\}. \end{equation} More precisely, \eqref{eq:peyre:concl} holds as soon as there are enumerations $A=\{a_1,\dots,a_N\}$ and $B=\{b_1,\dots,b_M\}$ such that \eqref{eq:peyre:hyp} holds for $i=a_k$, $j=b_l$ and the single set $S=\{a_1,\dots,a_{k-1}\}\cup\{b_1,\dots,b_{l-1}\}$, for all $1\le k\le N$ and $1\le l\le M$. \end{theorem} Here $\opnorm{\mathcal E}$ is the norm of $\mathcal E$ as an operator $\ell^2(B)\to\ell^2(A)$ (Euclidean norms, \cref{def:prelim:operators}), its largest singular value. The second statement has a weaker hypothesis, because the sets $S$ it uses are among those allowed in the first: they avoid $a_k$ and $b_l$. \Cref{app:peyre} gives the complete proof, which is Peyre's argument in finite form; the proof establishes the second statement directly. The paper applies only the first. \begin{corollary}[Independent pairs]\label{cor:peyre-independent} Let $(X_k,Y_k)$, $1\le k\le n$, be pairs of finite-valued random variables, the $n$ pairs independent of each other. Then \[ \rho\big((X_k)_k;(Y_k)_k\big)=\max_k\rho(X_k;Y_k). \] The same holds conditionally: if the triples $(X_k,Y_k,Z_k)$ are independent across $k$ and $z=(z_k)_k$ is a value of $(Z_k)_k$ of positive probability, then $\rho((X_k)_k;(Y_k)_k\mid(Z_k)_k=z)=\max_k\rho(X_k;Y_k\mid Z_k=z_k)$. \end{corollary} \begin{proof} Apply \cref{thm:peyre-finite} with $X_{a_k}=X_k$ and $X_{b_k}=Y_k$. Let $S$ avoid $a_k$ and $b_l$, and let $s$ be a value of $X_S$ of positive probability. The event $\{X_S=s\}$ is an intersection of events, one in each pair, so under $\Pr(\cdot\mid X_S=s)$ the pairs are still independent. If $k\ne l$, then $X_k$ and $Y_l$ lie in different pairs, are conditionally independent, and $\rho(X_k;Y_l\mid X_S=s)=0$. If $k=l$, the event depends only on the other pairs, the conditional law of $(X_k,Y_k)$ is its law, and $\rho(X_k;Y_k\mid X_S=s)=\rho(X_k;Y_k)$. So the hypothesis holds with the diagonal matrix $\mathcal E=\diag(\rho(X_k;Y_k))_k$, whose norm is $\max_k\rho(X_k;Y_k)$. The reverse inequality holds because functions of $X_k$ alone and of $Y_k$ alone are admissible in the definition of $\rho((X_k)_k;(Y_k)_k)$. For the conditional statement apply this under $\Pr(\cdot\mid(Z_k)_k=z)$: by the same product computation the pairs remain independent, with the conditional laws of $(X_k,Y_k)$ given $Z_k=z_k$. \end{proof} In operator form: the operator of a product of couplings is the tensor product of the operators of the factors, and its centred norm is the largest centred norm of a factor (\cref{lem:sector}(c)). \begin{corollary}[Conditional decorrelation]\label{cor:cond-decorrelation} Let $X,Y,Z$ be finite-valued random variables on a common probability space and $\eps\ge0$, and assume $\rho(X;Y\mid Z=z)\le\eps$ for every value $z$ with $\Pr(Z=z)>0$. If a real function $f\in L^2(X,Z)$ satisfies $\E[f\mid Z]=0$ and $g\in L^2(Y,Z)$ is real, then \[ |\E[fg]|\le\eps\,\norm f\,\norm{g-\E[g\mid Z]}\le\eps\norm f\norm g . \] \end{corollary} \begin{proof} This is \cref{lem:peyre:basic}(b), proved in \cref{app:peyre} on a finite space of full support (\cref{sec:peyre:conv}); every quantity here depends only on the joint law of $(X,Y,Z)$, so this is no restriction. The proof is fibrewise: on each set $\{Z=z\}$ of positive probability the hypothesis bounds $|\E[fg\mid Z=z]|$ by $\eps$ times the conditional norms of $f$ and of $g-\E[g\mid Z]$, and Cauchy--Schwarz for the sum over $z$ gives the claim. \end{proof} The two corollaries are used together when a law on a whole block is built from feature functions (the block step of \cref{lem:oct24:feature-block}): given a function of all the labels of a block, the conditional correlation tensorizes over the primes of the block (\cref{cor:peyre-independent}), and a function with conditional mean zero is then decorrelated from every function of the other side (\cref{cor:cond-decorrelation}). \begin{theorem}[Kassabov's angle inequality {\cite[Lemma~4.2(b)]{Kassabov}}]\label{thm:kassabov} Let $V_1,V_2,V_3$ be subspaces of a finite-dimensional Hilbert space and put $\eps_{ij}=\cos\angle(V_i,V_j)$. If $\eps_{13}<1$ and $\eps_{23}<1$, then \[ \cos\angle(V_1\cap V_3,V_2\cap V_3)\le\frac{\eps_{12}+\eps_{13}\eps_{23}}{\sqrt{(1-\eps_{13}^2)(1-\eps_{23}^2)}} . \] \end{theorem} It enters through the elimination of pinned vertices in \cref{lem:mid:allpin}, and through it in the pinned influence theorem \cref{prop:middle-negative}. \subsection{Monotone majorants: a bound at the smallest prime implies the bound at every larger prime}\label{subsec:notation:majorants} Every local constant of Part~V is an explicit expression in a prime $p$. It is computed once, at the start $X$ of a range of primes (a piece of the middle range, an upper band, the tail threshold), and then used at every prime $p\ge X$ and on every block of primes of the range. This is valid because each such constant, written as a function of the real variables $r=p^{-1/2}$, $q=1/p$, $\lambda=1/\log p$ and a block count (the number of primes in the block), is nondecreasing in each of them. To write a constant in these variables replace $p$ by $r^{-2}$: for instance $p/(p-1)=1/(1-r^2)$, $1/(p-1)=r^2/(1-r^2)$, $k/(p-k)=kr^2/(1-kr^2)$ and $k/p=kr^2$ for a fixed number $k$. ``Nondecreasing'' always refers to these variables. The definition and the lemma below record the calculus once; every section that evaluates a constant at an endpoint cites the lemma and displays the constant in a form built from its operations. \begin{definition}[Admissible and small functions]\label{def:majorant} A \emph{box} is a product $\Delta=I_1\times\dots\times I_k$ of intervals $I_j\subseteq[0,\infty)$, each containing its supremum $x^+_j<\infty$; the point $x^+=(x^+_1,\dots,x^+_k)$ is its \emph{endpoint}, and $\Delta$ is ordered coordinatewise. A function $\varphi\colon\Delta\to[0,\infty)$ is \emph{admissible} if $\varphi(x)\le\varphi(x')$ whenever $x\le x'$. If $r$ is a coordinate whose interval lies in $(0,\infty)$, then $\varphi$ is \emph{small} if $\varphi/r$ is admissible. A map $F\colon\mathcal D\to[0,\infty)$ on a set $\mathcal D\subseteq[0,\infty)^m$ is \emph{monotone} if $F(y)\le F(y')$ whenever $y\le y'$ in $\mathcal D$. \end{definition} \begin{lemma}[Admissible majorants]\label{lem:majorant} Let $\Delta$ be a box with endpoint $x^+$. \begin{enumerate}[label=\textup{(\roman*)}] \item Nonnegative constants, the coordinates, and every power series in the coordinates with nonnegative coefficients that converges on $\Delta$ are admissible; such a series in which every monomial contains $r$ is small. In particular every polynomial in $r$ with nonnegative coefficients, such as a count error of \cref{lem:extension}, and $p/(p-1)=1/(1-r^2)$ are admissible. \item If $F\colon\mathcal D\to[0,\infty)$ is monotone and $\varphi_1,\dots,\varphi_m$ are admissible with $(\varphi_1(x),\dots,\varphi_m(x))\in\mathcal D$ for every $x\in\Delta$, then $F(\varphi_1,\dots,\varphi_m)$ is admissible. Hence sums, products, maxima, minima and square roots of admissible functions, and powers $\varphi^\psi$ with $\varphi\ge1$, are admissible; so are $e^\varphi$, $e^\varphi-1$, $(e^\varphi-1)/\varphi$ (with value $1$ where $\varphi=0$) and $\log(1+\varphi)$, and, where $\varphi<1$ on $\Delta$, also $1/(1-\varphi)$, $(1+\varphi)/(1-\varphi)$ and $-\log(1-\varphi)$; and so are the operator norm of a matrix whose entries are admissible and the largest eigenvalue of a real symmetric matrix whose entries are admissible. Finally, $(G,D,r)\mapsto G+D^2r/(1+Gr)$ is monotone on $\{G,D,r\ge0,\ Dr\le1\}$, so $\varphi_G+\varphi_D^2\varphi_r/(1+\varphi_G\varphi_r)$ is admissible for admissible $\varphi_G,\varphi_D,\varphi_r$ with $\varphi_D\varphi_r\le1$ on $\Delta$. \item Every small function is admissible. If $\varphi,\psi$ are small and $h$ is admissible, then $\varphi+\psi$, $\max(\varphi,\psi)$, $\min(\varphi,\psi)$, $h\varphi$ and $\sqrt{\varphi\psi}$ are small. If $F(y)=yG(y)$ with $G\ge0$ monotone, then $F\circ\varphi$ is small for small $\varphi$ (with values in the domain of $G$); in particular $e^\varphi-1$, and, where $\varphi<1$, $-\log(1-\varphi)$, $\varphi/(1-\varphi)$ and $(1+\varphi)/(1-\varphi)-1$ are small. If $\varphi_1,\dots,\varphi_n$ are small, then $\prod_i(1+\varphi_i)-1$ is small. The function $\log(1+\varphi)$ need not be small: $\log(1+y)/y$ decreases. \item One fixed candidate, chosen independently of $x$ (for instance by its value at the endpoint), among finitely many admissible candidates is admissible. If $\varphi$ is admissible and $\psi\le\varphi$ on $\Delta$, then $\max(\varphi,\psi)=\varphi$ is admissible, whatever $\psi$ is. \end{enumerate} Consequently the following hold. \begin{enumerate}[label=\textup{(\alph*)}] \item \emph{Endpoint.} If $\varphi$ is admissible, then $\varphi(x)\le\varphi(x^+)$ for every $x\in\Delta$. In particular, let $P>1$ and $L\ge0$ be real, and let $\Delta=(0,P^{-1/2}]\times(0,1/P]\times(0,1/\log P]\times[0,L/\log P]$ in the variables $r$, $q$, $\lambda$ and the block count (or a product of some of these factors). Then every inequality of the form $\varphi(x^+)1$, $q_X=1/X$, $r_X\ge X^{-1/2}$ and $n_X\ge0$ (the certificates use $r_X=1/\lfloor\sqrt X\rfloor$), and let $\varphi(q,r,l)$ be admissible on the box $(0,q_X]\times(0,r_X]\times[0,n_X]$. If a quantity at the prime $p$ with block count $l\le n_X$ is $r^d\varphi(q,r,l)$, where $d\ge0$, $r=p^{-1/2}$ and $q=1/p$, then for every prime $p\ge X$ it is at most $p^{-d/2}\varphi(q_X,r_X,n_X)$. \item \emph{Block inflation.} Let $c\ge0$ and $L>0$. The function $X\mapsto\exp(cL/(X\log X))$ is nonincreasing on $(1,\infty)$ (decreasing if $c>0$). If $\Blk$ is a set of primes, all at least $X>1$, with $q_\Blk\le e^L$, then $|\Blk|\le L/\log X$, $\sum_{p\in\Blk}1/p\le L/(X\log X)$ and $\prod_{p\in\Blk}(1+c/p)\le\exp(cL/(X\log X))$. \item \emph{Matrix tests.} Let $M_0$ be a fixed Hermitian matrix and $E_1,\dots,E_m\succeq0$ fixed positive semidefinite matrices of the same size, and let $c_1,\dots,c_m$ be real functions on $\Delta$ with $c_i(x)\ge c_i(x^+)$ for every $x$ (for instance $c_i=-\varphi_i$, or $c_i=g/\varphi_i$ with a constant $g\ge0$ independent of $x$, where $\varphi_i>0$ is admissible). If $M_0+\sum_ic_i(x^+)E_i\succeq0$, then $M_0+\sum_ic_i(x)E_i\succeq0$ for every $x\in\Delta$. \item \emph{Several thresholds.} Let $\mathcal A(p,g)$ be a statement about a prime $p$ and a number $g$ that remains true when $g$ is increased (for instance $C_p\succeq-gp^{-1/2}I$, $C_p\preceq(1+g/p)I$ or $c(p)\le g$). If, for each $s$ in a finite set, $\mathcal A(p,g_s)$ holds for every prime $p\ge y_s$, then $\mathcal A(p,\min\{g_s:y_s\le y\})$ holds for every prime $p\ge y$ and every real $y\ge\min_sy_s$. \end{enumerate} \end{lemma} \begin{proof} (i) For $0\le x\le x'$ every monomial satisfies $x^\alpha\le x'^\alpha$, so a series with nonnegative coefficients is admissible. If every monomial contains $r$, the series is $r$ times a series with nonnegative coefficients, which converges on $\Delta$ because $r>0$ there; so it is small. The count errors are polynomials in $r$ with nonnegative coefficients, and $1/(1-r^2)=\sum_{k\ge0}r^{2k}$ for $r<1$. (ii) If $x\le x'$, then $\varphi_i(x)\le\varphi_i(x')$ for every $i$, and the monotonicity of $F$ gives the claim. The listed maps are monotone on their domains: $(y,z)\mapsto y+z$, $yz$, $\max(y,z)$, $\min(y,z)$ on $[0,\infty)^2$; $y\mapsto\sqrt y$; $(y,z)\mapsto y^z$ on $[1,\infty)\times[0,\infty)$; $y\mapsto e^y$, $e^y-1$, $(e^y-1)/y=\sum_{k\ge0}y^k/(k+1)!$ and $\log(1+y)$ on $[0,\infty)$; and $y\mapsto1/(1-y)=\sum_ky^k$, $(1+y)/(1-y)=1+2\sum_{k\ge1}y^k$ and $-\log(1-y)=\sum_{k\ge1}y^k/k$ on $[0,1)$. For real matrices with $0\le M\le M'$ entrywise and unit vectors $u,v$, $|v^*Mu|\le|v|^{\mathsf T}M|u|\le|v|^{\mathsf T}M'|u|\le\|M'\|$, where $|u|$ is the vector of moduli; so $\|M\|\le\|M'\|$. For real symmetric $M\ge0$, $u^{\mathsf T}Mu\le|u|^{\mathsf T}M|u|$, so the largest eigenvalue is the maximum of $u^{\mathsf T}Mu$ over nonnegative unit vectors $u$, which is monotone in the entries in the same way. Finally, on $\mathcal D=\{G,D,r\ge0,\ Dr\le1\}$ the map $F(G,D,r)=G+D^2r/(1+Gr)$ has the partial derivatives $1-D^2r^2/(1+Gr)^2\ge0$ (as $Dr\le1\le1+Gr$), $2Dr/(1+Gr)\ge0$ and $D^2/(1+Gr)^2\ge0$. If $y\le y'$ in $\mathcal D$, the path from $y$ to $y'$ that raises first $G$, then $D$, then $r$ stays in $\mathcal D$, because the product $Dr$ only increases along it, up to its value at $y'$; so $F(y)\le F(y')$. (iii) A small $\varphi=r\varphi'$ is a product of admissible functions. Write also $\psi=r\psi'$. Then $\varphi+\psi=r(\varphi'+\psi')$, $\max(\varphi,\psi)=r\max(\varphi',\psi')$, $\min(\varphi,\psi)=r\min(\varphi',\psi')$, $h\varphi=rh\varphi'$ and $\sqrt{\varphi\psi}=r\sqrt{\varphi'\psi'}$, and (ii) applies to the cofactors. If $F(y)=yG(y)$, then $F(\varphi)/r=G(\varphi)\varphi'$, admissible by (ii); this covers $e^y-1$ with $G(y)=(e^y-1)/y$, $-\log(1-y)$ with $G(y)=\sum_{k\ge1}y^{k-1}/k$, $y/(1-y)$ with $G(y)=1/(1-y)$, and $(1+y)/(1-y)-1=2y/(1-y)$. Finally $\prod_i(1+\varphi_i)-1=\sum_{\emptyset\ne I}\prod_{i\in I}\varphi_i$, and each term is a small function times admissible ones. (iv) A choice made once is a fixed admissible function, and $\max(\varphi,\psi)=\varphi$ when $\psi\le\varphi$. (a) Every $x\in\Delta$ satisfies $x\le x^+$. For a prime $p\ge P>1$, $p^{-1/2}\le P^{-1/2}$, $1/p\le1/P$ and $1/\log p\le1/\log P$. (b) For a prime $p\ge X$, $1/p\le q_X$, $p^{-1/2}\le X^{-1/2}\le r_X$ and $l\le n_X$, so $\varphi(1/p,p^{-1/2},l)\le\varphi(q_X,r_X,n_X)$ by (a); multiply by $p^{-d/2}$. (c) The function $X\log X$ is positive on $(1,\infty)$, with derivative $\log X+1>0$. Every prime of $\Blk$ is at least $X$, so $|\Blk|\log X\le\log q_\Blk\le L$; then $\sum_{p\in\Blk}1/p\le|\Blk|/X\le L/(X\log X)$, and $\prod_{p\in\Blk}(1+c/p)\le\exp(c\sum_{p\in\Blk}1/p)$. (d) The difference of the two matrices is $\sum_i(c_i(x)-c_i(x^+))E_i\succeq0$. (e) Every $s$ with $y_s\le y$ gives $\mathcal A(p,g_s)$ at every prime $p\ge y\ge y_s$, hence $\mathcal A(p,g)$ for the smallest such $g_s$. \end{proof} \begin{remark}[How the lemma is applied]\label{rem:majorant-use} (1) \emph{Cancel the powers of $r$ first.} A remainder of the form $q\cdot c(q,r)$ is used as $r\cdot(rc(q,r))$, with the admissible coefficient $rc(q,r)$, before the piece start is used. At the piece start the coefficient is evaluated at $q_X=1/X$ and $r_X=1/\lfloor\sqrt X\rfloor\ge X^{-1/2}$, and the bound used for a block with least prime $b\ge X$ is $b^{-1/2}$ times this coefficient (part (b) with $d=1$). A remainder computed at $q_X$ and then divided by the larger $r_X$ would not in general bound the coefficient, since $q_X/r_XX^{-1/2}$; this is never done. (2) \emph{Logarithmic counts.} Inserting the vertices of a labelling in a fixed order, with the count errors of \cref{lem:extension} at each step, gives logarithmic count bounds. Where such a bound must be small in the sense of \cref{def:majorant} it is used in the form $\sum e$, an upper bound for $\sum\log(1+e)$, or $\sum-\log(1-e)$; both are small when the count errors $e$ are, whereas $\sum\log(1+e)$ is admissible but in general not small. (3) \emph{Choices and gates.} Orders, partitions, Schur-test parameters and the branch of a maximum are fixed at the endpoint before (a) is applied. A minimum of bounds is taken only among bounds whose own hypotheses, which are gates, hold at the endpoint, and hence everywhere by (a). No monotonicity of an eigenvector or of an optimized parameter is used. When one branch of a maximum is not monotone, (iv) applies once it is shown to be dominated by an admissible branch; this is how the two branches of the maximum in the spectral criterion are treated (\cref{lem:spectral-monotone,lem:record:monotone-endpoint}). (4) \emph{Classes.} A matrix test whose matrices depend on $p$ only through $p\bmod4$ is checked for both classes, and (d) is applied within each class. The threshold hypotheses of spectral data are gates built from the operations of (i) and (ii), and persist by (a). A spectral cap valid for every prime $p\ge P$, times the block inflation of (c) evaluated at the start $X\ge P$ of a piece or band, bounds the corresponding factor on every block of that piece or band (\cref{cor:spectral-criterion-blocks}). \end{remark} \paragraph{Consequences and what to read next.} External inputs: Weil's theorem (\cref{thm:weil}(a)), the explicit Chebyshev bound of Bennett, Martin, O'Bryant and Rechnitzer (\cref{thm:bmor}) and Kassabov's inequality (\cref{thm:kassabov}); \cref{subsec:external:sources} gives their sources. Peyre's theorem (\cref{thm:peyre-finite}) and the conditional decorrelation inequality (\cref{cor:cond-decorrelation}) are proved in \cref{app:peyre}. Everything else is proved here from standard facts: the cyclicity of $\Fp^\times$, the Chinese remainder theorem, Hensel's lemma, Fourier analysis on finite abelian groups and the Cauchy--Schwarz inequality. \space % End sections/04_notation % Begin sections/05_positivity \section{Reflection positivity and a H\"older inequality for signed laws} \label{sec:positivity} \paragraph{What this section proves and how to read it.} This section proves that a signed $72$-fold average can still be bounded below by $\alpha^{72}$ and above by diagonal averages, provided the averaging law is positive across mirror symmetries. Precisely, it defines cuts and reflection positivity, proves that domination by a positive $2\times2$ block at one cut permits Cauchy--Schwarz for signed laws, iterates this over seven cuts to obtain the signed H\"older inequality, and constructs the $72$ slots with their seven cuts and six queries. Signed laws appear because the comparison law $\nu$ of Part~III cannot be reflection positive; the block domination is what replaces positivity for $\nu$. Inputs: only finite linear algebra. Outputs: \cref{thm:holder} (hence $\alpha^{72}\le Y$) and the block-domination calculus used in Part~III. A first reading should follow the definitions, \cref{thm:holder}, and the slot construction in \cref{subsec:slot-array}; the detailed one-cut lemmas can be treated as reference. Until \cref{subsec:slot-array}, $V$ is an arbitrary finite slot set; from there on $V=(\Z/6\Z)^2\times\{0,1\}$. \paragraph{Notation.} Throughout, $V$ is a finite set of \emph{slots}, $d=|V|$, and $\mathcal X$ is a finite set of labels. For a finite signed measure $\nu$ on $\mathcal X^V$ and real functions $g_v$ on $\mathcal X$ we write \[ \Lambda_\nu\big((g_v)_{v\in V}\big)=\int\prod_{v\in V}g_v(z_v)\,d\nu(z), \qquad \Lambda_\nu(g)=\Lambda_\nu\big((g)_{v\in V}\big). \] A map $h\colon V\to\R^{\mathcal X}$ is an \emph{assignment}, and $\Lambda_\nu(h)=\Lambda_\nu((h(v))_{v\in V})$. For a map $\Psi$ between finite sets, $\Psi_*\kappa$ is the image of a measure $\kappa$; for a permutation $\sigma$ of $V$ we write $\sigma_*\kappa$ for the image of $\kappa$ under the map $z\mapsto z\circ\sigma=(z_{\sigma v})_{v\in V}$ of $\mathcal X^V$. \subsection{Cuts and cut matrices}\label{subsec:pos:cuts} Laws obtained by restricting a law to an event, by repair, or as comparison laws are in general not reflection positive. Two facts replace positivity at a single cut: measures that the cut fixes samplewise are ordered in the Loewner order at that cut (\cref{lem:commoncut}), and a measure bracketed at one cut by a reflection positive law inherits that law's mixed H\"older bound (\cref{lem:record:block-gram}, \cref{rem:cc:mixed}). This subsection fixes the language. \begin{definition}[Cuts and reflection positivity]\label{def:rp} A \emph{cut} of $V$ is a fixed-point-free involution $\vartheta$ of $V$ together with a decomposition $V=V_+\sqcup V_-$ with $V_-=\vartheta V_+$; $V_+$ is its \emph{plus half}. We name a cut by its involution when the plus half is understood. A finite signed measure $\nu$ on $\mathcal X^V$ is \emph{reflection positive} (RP) at $\vartheta$ if it is invariant under $(z_v)_v\mapsto(z_{\vartheta v})_v$ and \[ \int F\big(z_{V_+}\big)\,F\big((z_{\vartheta u})_{u\in V_+}\big)\,d\nu(z)\ \ge\ 0 \qquad\text{for every }F\colon\mathcal X^{V_+}\to\R . \] Equivalently (\cref{def:cc:order}), its cut matrix $\big(\nu(z_{V_+}=x,\ z_{\vartheta V_+}=y)\big)_{x,y\in\mathcal X^{V_+}}$ is symmetric and positive semidefinite. \end{definition} Positive multiples and sums of measures that are RP at $\vartheta$ are RP at $\vartheta$, and so are tensor products of such measures \eqref{eq:cc:kron}. Since $|V|=2|V_+|$, a slot set with a cut has an even number of slots. \begin{definition}[Cut matrix, cut order and cut form]\label{def:cc:order} Fix a cut $\vartheta$ with halves $V_\pm$. For a finite signed measure $\nu$ on $\mathcal X^V$ its \emph{cut matrix} at $\vartheta$ is \[ C_\vartheta(\nu)_{x,y}=\nu\big(z_{V_+}=x,\ z_{\vartheta V_+}=y\big) \qquad(x,y\in\mathcal X^{V_+}), \] where $z_{V_+}=x$ means $z_u=x_u$ and $z_{\vartheta V_+}=y$ means $z_{\vartheta u}=y_u$ for all $u\in V_+$. For real symmetric matrices, $A\preceq B$ means that $B-A$ is positive semidefinite (the Loewner order of \cref{def:prelim:operators}). For finite signed measures $\kappa,\kappa'$ on $\mathcal X^V$ we write $\kappa\succeq_\vartheta\kappa'$, or $\kappa'\preceq_\vartheta\kappa$, if $C_\vartheta(\kappa-\kappa')$ is symmetric and positive semidefinite; thus $\nu$ is RP at $\vartheta$ if and only if $\nu\succeq_\vartheta0$. The \emph{cut form} of $\kappa$ at $\vartheta$ is the bilinear form \[ Q_\kappa(X,Y)=\ip{X}{C_\vartheta(\kappa)Y} =\int X\big(z_{V_+}\big)\,Y\big((z_{\vartheta u})_{u\in V_+}\big)\,d\kappa(z) \] on real functions $X,Y$ on $\mathcal X^{V_+}$ (\emph{half-functions}), with the Euclidean inner product of $\R^{\mathcal X^{V_+}}$. \end{definition} The map $z\mapsto\big(z_{V_+},(z_{\vartheta u})_{u\in V_+}\big)$ is a bijection of $\mathcal X^V$ onto $\mathcal X^{V_+}\times\mathcal X^{V_+}$, so a measure is determined by its cut matrix at any one cut. The cut form $Q_\kappa(X,Y)$ is bilinear in $(X,Y)$ and linear in $\kappa$; if $\kappa\succeq_\vartheta0$ it is a symmetric positive semidefinite form, and $\kappa\preceq_\vartheta\kappa'$ implies $Q_\kappa(X,X)\le Q_{\kappa'}(X,X)$ for every $X$. \emph{The bilinear identity.} For real $g_v$ on $\mathcal X$ put $F(x)=\prod_{u\in V_+}g_u(x_u)$ and $G(y)=\prod_{u\in V_+}g_{\vartheta u}(y_u)$. Since $V=V_+\sqcup\vartheta V_+$, \begin{equation}\label{eq:cc:bilinear} \Lambda_\nu\big((g_v)_{v\in V}\big)=\sum_{x,y}F(x)\,C_\vartheta(\nu)_{x,y}\,G(y) =\ip{F}{C_\vartheta(\nu)G}=Q_\nu(F,G). \end{equation} When every $g_v$ equals $g$, both $F$ and $G$ are the half-function $F_g(x)=\prod_{u\in V_+}g(x_u)$ carrying $g$ at every slot of the plus half; so $\Lambda_\nu(g)=Q_\nu(F_g,F_g)$, at every cut of $V$. \emph{Products.} If $\nu_1$, $\nu_2$ are finite signed measures on $\mathcal X_1^V$, $\mathcal X_2^V$, we write $\nu_1\otimes\nu_2$ for the image of the product measure under $(z^1,z^2)\mapsto((z^1_v,z^2_v))_{v\in V}$, a measure on $(\mathcal X_1\times\mathcal X_2)^V$. Under the identification $(\mathcal X_1\times\mathcal X_2)^{V_+}=\mathcal X_1^{V_+}\times \mathcal X_2^{V_+}$, \begin{equation}\label{eq:cc:kron} C_\vartheta(\nu_1\otimes\nu_2)=C_\vartheta(\nu_1)\otimes C_\vartheta(\nu_2) \qquad\text{(Kronecker product)}, \end{equation} because the entry at $((x^1,x^2),(y^1,y^2))$ factors. A Kronecker product of symmetric positive semidefinite matrices is symmetric positive semidefinite (its eigenvalues are the products of those of the factors). Hence $\kappa_i\succeq_\vartheta0$ for all $i$ implies $\bigotimes_i\kappa_i\succeq_\vartheta0$. \begin{remark}[Reflections, halves and permutations]\label{rem:cut-symmetries} Let $\kappa$ be a finite signed measure on $\mathcal X^V$ and $\vartheta$ a cut. \begin{enumerate}[label=(\alph*)] \item \emph{Reflection.} $C_\vartheta(\vartheta_*\kappa)=C_\vartheta(\kappa)^{\mathsf T}$, since $\vartheta_*\kappa(z_{V_+}=x,\ z_{\vartheta V_+}=y) =\kappa(z_{\vartheta V_+}=x,\ z_{V_+}=y)$. As $\kappa$ is determined by its cut matrix, $\kappa$ is invariant under the reflection if and only if $C_\vartheta(\kappa)$ is symmetric. The \emph{symmetric} and \emph{skew parts} $\frac12(\kappa\pm\vartheta_*\kappa)$ have the symmetric and the antisymmetric part of $C_\vartheta(\kappa)$ as cut matrices. The diagonal cut form of a measure with antisymmetric cut matrix vanishes, and so does that of its product with any measure with symmetric cut matrix \eqref{eq:cc:kron}. \item \emph{Halves.} $(\vartheta,V_-)$ is again a cut. Identify $\mathcal X^{V_-}$ with $\mathcal X^{V_+}$ by $x\mapsto(x_{\vartheta u})_{u\in V_+}$; then the cut matrix at $(\vartheta,V_-)$ is the transpose of the cut matrix at $(\vartheta,V_+)$. Hence $\kappa\succeq\kappa'$ at one choice of the plus half if and only if at the other; in particular reflection positivity does not depend on the choice of the plus half. \item \emph{Permutations.} For a permutation $\sigma$ of $V$, the involution $\sigma^{-1}\vartheta\sigma$ with plus half $\sigma^{-1}V_+$ is a cut, and $s(x)=(x_{\sigma u})_{u\in\sigma^{-1}V_+}$ is a bijection $\mathcal X^{V_+}\to\mathcal X^{\sigma^{-1}V_+}$ with \[ C_{\sigma^{-1}\vartheta\sigma}(\sigma_*\kappa)_{s(x),s(y)}=C_\vartheta(\kappa)_{x,y}. \] Indeed, for $w=z\circ\sigma$ we have $w_{\sigma^{-1}V_+}=s(z_{V_+})$ and $(w_{\sigma^{-1}\vartheta\sigma u})_{u\in\sigma^{-1}V_+}=s((z_{\vartheta v})_{v\in V_+})$. Hence $\kappa\succeq_\vartheta\kappa'$ if and only if $\sigma_*\kappa\succeq_{\sigma^{-1}\vartheta\sigma}\sigma_*\kappa'$. \end{enumerate} \end{remark} \begin{lemma}[Common-cut order]\label{lem:commoncut} Let $\vartheta$ be a cut of $V$ with halves $V_\pm$, and let $\operatorname{Fix}(\vartheta)=\{z\in\mathcal X^V:z_{\vartheta v}=z_v\ \text{for all }v\in V\}$. \begin{enumerate}[label=(\roman*)] \item \emph{Diagonal measures.} Let $\kappa$ be a nonnegative measure on $\mathcal X^V$ supported on $\operatorname{Fix}(\vartheta)$; we say that $\kappa$ is \emph{diagonal at $\vartheta$}, or \emph{fixed samplewise by $\vartheta$}. Then $C_\vartheta(\kappa)$ is diagonal with entries $\kappa(z_{V_+}=x)\ge0$; in particular $\kappa\succeq_\vartheta0$, and $\kappa$ is RP at $\vartheta$. Every nonnegative measure whose support lies in that of $\kappa$ is again diagonal at $\vartheta$: a restriction of $\kappa$ to an event, a nonnegative reweighting of $\kappa$, and, if $\kappa=Z_*\pi$ for a finite set $\Omega$ with weights $\pi\ge0$ and a map $Z\colon\Omega\to\mathcal X^V$ (a \emph{latent representation}), every $Z_*(w\pi)$ with $w\ge0$ on $\Omega$ (a restriction to latent events if $w$ is an indicator). For a finite nonnegative measure $m$ on $\mathcal X^{V_+}$, the \emph{diagonal copy} $\operatorname{Diag}_\vartheta(m)$, the image of $m$ under the map $x\mapsto z$ with $z_{V_+}=x$ and $z_{\vartheta u}=x_u$ for $u\in V_+$ (for a probability measure $m$: the law of $z$ with $z_{V_+}\sim m$ and $z_{\vartheta u}=z_u$), is diagonal at $\vartheta$ with cut matrix $\operatorname{diag}(m)$. \item \emph{Order.} If $\kappa,\kappa_1,\dots,\kappa_k$ are diagonal at $\vartheta$ and $\kappa\le\sum_i\kappa_i$, then $0\preceq_\vartheta\kappa\preceq_\vartheta\sum_i\kappa_i$. \item \emph{Adjoining a factor.} If $\kappa\preceq_\vartheta\kappa'$ on $\mathcal X^V$ and $\rho$ is a finite signed measure on $\mathcal Y^V$ with $\rho\succeq_\vartheta0$, then $\kappa\otimes\rho\preceq_\vartheta\kappa'\otimes\rho$ on $(\mathcal X\times\mathcal Y)^V$. In particular (ii) persists after adjoining $\rho$. \item \emph{Diagonal functionals.} Consequently, in the situation of (ii) and (iii), $0\le\Lambda_{\kappa\otimes\rho}(g)\le\sum_i\Lambda_{\kappa_i\otimes\rho}(g)$ for every real function $g$ on $\mathcal X\times\mathcal Y$. \item \emph{One kernel on both halves.} Let $\vartheta'$ be a cut of a finite set $W$ with halves $W_\pm$, $\mathcal Y$ a finite set, and $P$ a Markov kernel from $\mathcal X^{V_+}$ to $\mathcal Y^{W_+}$ (a nonnegative matrix with unit row sums). For a finite signed measure $\kappa$ on $\mathcal X^V$ let $\kappa^P$ be the measure on $\mathcal Y^W$ obtained by applying $P$ independently to $z_{V_+}$ and to the reflected minus half $(z_{\vartheta u})_{u\in V_+}$, and placing the results on $W_+$ and, through $\vartheta'$, on $W_-$: \[ \kappa^P(w)=\sum_{z}\kappa(z)\,P\big(z_{V_+},w_{W_+}\big)\, P\big((z_{\vartheta u})_{u\in V_+},(w_{\vartheta'u'})_{u'\in W_+}\big). \] Then $C_{\vartheta'}(\kappa^P)=P^{\mathsf T}C_\vartheta(\kappa)P$; so $\kappa\succeq_\vartheta\kappa'$ implies $\kappa^P\succeq_{\vartheta'}\kappa'^P$. The measure $\kappa^P$ is nonnegative if $\kappa$ is, has the mass of $\kappa$, and has plus-half marginal $mP$ if $\kappa$ has plus-half marginal $m$. For a finite nonnegative measure $m$ on $\mathcal X^{V_+}$, $P^{\mathsf T}\operatorname{diag}(m)P\preceq\operatorname{diag}(mP)$; hence $\pi+k\operatorname{Diag}_\vartheta(m)\succeq_\vartheta0$ with $k\ge0$ implies $\pi^P+k\operatorname{Diag}_{\vartheta'}(mP)\succeq_{\vartheta'}0$. If $P$ is deterministic, $P(x,\cdot)=\delta_{\phi(x)}$, then $\kappa^P=\Phi_*\kappa$ for the \emph{half-local} map $\Phi\colon\mathcal X^V\to\mathcal Y^W$ with \[ \Phi(z)_{W_+}=\phi(z_{V_+}),\qquad \big(\Phi(z)_{\vartheta'u'}\big)_{u'\in W_+}=\phi\big((z_{\vartheta u})_{u\in V_+}\big); \] the map $\Phi$ intertwines the two reflections, it maps $\operatorname{Fix}(\vartheta)$ into $\operatorname{Fix}(\vartheta')$, and $\Phi_*\operatorname{Diag}_\vartheta(m)=\operatorname{Diag}_{\vartheta'}(\phi_*m)$. \end{enumerate} \end{lemma} \begin{proof} (i) $C_\vartheta(\kappa)_{x,y}=\kappa(z_{V_+}=x,\ z_{\vartheta V_+}=y)$. On $\operatorname{Fix}(\vartheta)$ we have $(z_{\vartheta u})_{u\in V_+}=z_{V_+}$, so the entry vanishes unless $y=x$, and the diagonal entries are $\kappa(z_{V_+}=x)\ge0$. A nonnegative diagonal matrix is symmetric and positive semidefinite. The support of $Z_*(w\pi)$ is contained in $Z(\{\pi>0\})$, which is the support of $\kappa$. The diagonal copy is supported on $\operatorname{Fix}(\vartheta)$, with diagonal entries $m(x)$. (ii) $\sum_i\kappa_i-\kappa$ is a nonnegative measure supported in $\bigcup_i\operatorname{supp}\kappa_i\subseteq\operatorname{Fix}(\vartheta)$. By linearity of $C_\vartheta$ and (i), $C_\vartheta(\sum_i\kappa_i)-C_\vartheta(\kappa)$ is nonnegative diagonal, and $C_\vartheta(\kappa)\succeq0$ by (i). (iii) By \eqref{eq:cc:kron}, $C_\vartheta(\kappa'\otimes\rho)-C_\vartheta(\kappa\otimes\rho) =C_\vartheta(\kappa'-\kappa)\otimes C_\vartheta(\rho)$, a Kronecker product of two symmetric positive semidefinite matrices. (iv) Apply \eqref{eq:cc:bilinear} with the same real vector $F_g$ on both sides of the inequalities of (ii) and (iii). (v) For $x',y'\in\mathcal Y^{W_+}$, \[ C_{\vartheta'}(\kappa^P)_{x',y'} =\sum_z\kappa(z)P\big(z_{V_+},x'\big)P\big((z_{\vartheta u})_u,y'\big) =\sum_{x,y}C_\vartheta(\kappa)_{x,y}P(x,x')P(y,y'), \] which is the matrix identity. Thus $\ip{G}{C_{\vartheta'}(\kappa^P)G}=\ip{PG}{C_\vartheta(\kappa)PG}$ for every real $G$, and $P^{\mathsf T}CP$ is symmetric when $C$ is; this gives the order statement. Nonnegativity, the mass and the marginal follow from the unit row sums. For the diagonal, by Jensen's inequality for each row of $P$, \[ \ip{G}{P^{\mathsf T}\operatorname{diag}(m)PG}=\sum_xm(x)\,(PG)(x)^2 \le\sum_xm(x)\,(PG^2)(x)=\ip{G}{\operatorname{diag}(mP)G}, \] so $C_{\vartheta'}(\pi^P)+k\operatorname{diag}(mP)\succeq P^{\mathsf T}\big(C_\vartheta(\pi)+k\operatorname{diag}(m)\big)P\succeq0$, and the left side is symmetric. If $P$ is deterministic, the defining sum collapses to $\Phi_*\kappa$. Since $(z\circ\vartheta)_{V_+}=(z_{\vartheta u})_u$ and $((z\circ\vartheta)_{\vartheta u})_u=z_{V_+}$, we get $\Phi(z\circ\vartheta)=\Phi(z)\circ\vartheta'$; for $z\in\operatorname{Fix}(\vartheta)$ both halves of $\Phi(z)$ are $\phi(z_{V_+})$, so $\Phi(z)\in\operatorname{Fix}(\vartheta')$. Finally $P^{\mathsf T}\operatorname{diag}(m)P=\operatorname{diag}(\phi_*m)$, and two measures with the same cut matrix coincide. \end{proof} \begin{remark}[Limits of the common-cut order]\label{rem:cc:limits} \begin{enumerate}[label=(\alph*)] \item Part (iv) is a union bound in the cone of positive semidefinite cut matrices, not a pointwise inequality for the integrand: a product of Fourier lifts can be negative. A Boolean cover $\one_B\le\sum_F\one_{I_F}$ of events of a latent representation therefore becomes the inequality $0\le\Lambda_{Z_*(\one_B\pi)\otimes\rho}(g)\le\sum_F\Lambda_{Z_*(\one_{I_F}\pi)\otimes\rho}(g)$ of diagonal functionals. \item The samplewise hypothesis is essential. Being supported on $\operatorname{Fix}(\vartheta)$ is a property of the samples; invariance of a measure under the reflection does not imply it, and reflection positivity of a measure at every cut does not make its restrictions to events positive semidefinite at a chosen cut without an additional argument. This is one reason why the residues modulo the small modulus and the position of an integer among the intervals are external indices of the comparison (\cref{def:hyb:coupled}) and not coordinates of the labels: a reference law carrying correlated residues would have to be restricted to events of the residues, and such restrictions need not remain positive semidefinite at the cuts where positivity is required. \end{enumerate} \end{remark} \subsection{Controlling a law that is not reflection positive by two reflection-positive laws (\texorpdfstring{$2\times2$}{2 x 2} blocks)}\label{subsec:pos:brackets} If a block matrix of two positive semidefinite diagonal blocks is positive semidefinite, its off-diagonal block is bounded by the diagonal ones. Such a \emph{bracket} controls a measure that is not reflection positive at a cut by two positive ones, and brackets tensorize. This is how the comparison law, which is not reflection positive, is controlled at the reserved cut. \begin{lemma}[Block-Gram calculus]\label{lem:record:block-gram} Let $\mathcal H,\mathcal H',\mathcal H_1,\dots,\mathcal H_n$ be finite-dimensional Hilbert spaces. \begin{enumerate}[label=(\alph*)] \item \emph{Brackets.} For operators $M$ on $\mathcal H$, $M'$ on $\mathcal H'$ and $K\colon\mathcal H'\to\mathcal H$, the block operator $\bigl(\begin{smallmatrix}M&K\\ K^*&M'\end{smallmatrix}\bigr)$ on $\mathcal H\oplus\mathcal H'$ is positive semidefinite if and only if $M\succeq0$, $M'\succeq0$ and $K=M^{1/2}CM'^{1/2}$ for an operator $C$ with $\|C\|\le1$. Then $|\ip{x}{Ky}|\le\ip{x}{Mx}^{1/2}\ip{y}{M'y}^{1/2}$. \item \emph{Tensorization.} If $\bigl(\begin{smallmatrix}M_i&K_i\\ K_i^*&M_i'\end{smallmatrix}\bigr)\succeq0$ on $\mathcal H_i\oplus\mathcal H_i$ for each $i$, then the same holds for $M=\bigotimes_iM_i$, $M'=\bigotimes_iM_i'$ and $K=\bigotimes_iK_i$, and $|\ip{x}{Ky}|\le\ip{x}{Mx}^{1/2}\ip{y}{M'y}^{1/2}$. \item \emph{Modulus.} Every operator $T$ on a finite-dimensional Hilbert space satisfies \[ \begin{pmatrix}|T^*|&T\\ T^*&|T|\end{pmatrix}\succeq0, \qquad |T|=(T^*T)^{1/2},\quad |T^*|=(TT^*)^{1/2}. \] \item \emph{Symmetric brackets.} For self-adjoint $M$, $K$, $\bigl(\begin{smallmatrix}M&K\\ K&M\end{smallmatrix}\bigr)\succeq0$ if and only if $M\pm K\succeq0$. If $A_i$, $B_i$ are self-adjoint with $A_i\pm B_i\succeq0$ for every $i$, then $\bigotimes_iA_i\pm\bigotimes_iB_i\succeq0$; for two factors, explicitly, \[ 2\,(A\otimes N\pm D\otimes G)=(A\pm D)\otimes(N+G)+(A\mp D)\otimes(N-G). \] In particular $0\preceq A_i\preceq A_i'$ for every $i$ implies $\bigotimes_iA_i\preceq\bigotimes_iA_i'$. \end{enumerate} \end{lemma} \begin{proof} (a) The diagonal blocks of a positive semidefinite block operator are positive semidefinite. If $K=M^{1/2}CM'^{1/2}$ with $\|C\|\le1$, the form of the block operator at $(x,y)$ is at least $\|M^{1/2}x\|^2-2\|M^{1/2}x\|\,\|M'^{1/2}y\|+\|M'^{1/2}y\|^2\ge0$. Conversely, for $\epsilon>0$ conjugate the block operator plus $\epsilon$ by $\operatorname{diag}((M+\epsilon)^{-1/2},(M'+\epsilon)^{-1/2})$: the result $\bigl(\begin{smallmatrix}I&C_\epsilon\\ C_\epsilon^*&I\end{smallmatrix}\bigr)$, $C_\epsilon=(M+\epsilon)^{-1/2}K(M'+\epsilon)^{-1/2}$, is positive definite, and its form at $(x,-C_\epsilon^*x)$ is $\|x\|^2-\|C_\epsilon^*x\|^2$, so $\|C_\epsilon\|\le1$. Since $K=(M+\epsilon)^{1/2}C_\epsilon(M'+\epsilon)^{1/2}$ for every $\epsilon$, any limit point $C$ of $C_\epsilon$ as $\epsilon\to0$ is a contraction with $K=M^{1/2}CM'^{1/2}$, by continuity of the square root. The inequality is Cauchy--Schwarz: $|\ip{x}{Ky}|=|\ip{M^{1/2}x}{CM'^{1/2}y}|$. (b) Write $K_i=M_i^{1/2}C_iM_i'^{1/2}$ by (a). The square root of a tensor product of positive semidefinite operators is the tensor product of the square roots, so $K=M^{1/2}\big(\bigotimes_iC_i\big)M'^{1/2}$, and $\|\bigotimes_iC_i\|=\prod_i\|C_i\|\le1$; apply (a). (c) Let $T=U|T|$ with $U$ unitary. Then $|T^*|=U|T|U^*$, and the block operator equals $X|T|X^*$, where $X$ is the column operator $h\mapsto(Uh,h)$ into $\mathcal H\oplus\mathcal H$; indeed $X^*(a,b)=U^*a+b$, $U|T|=T$ and $|T|U^*=T^*$. (d) Conjugation by the unitary $\frac1{\sqrt2}\bigl(\begin{smallmatrix}I&I\\ I&-I\end{smallmatrix}\bigr)$ turns $\bigl(\begin{smallmatrix}M&K\\ K&M\end{smallmatrix}\bigr)$ into $\bigl(\begin{smallmatrix}M+K&0\\ 0&M-K\end{smallmatrix}\bigr)$. If $A_i\pm B_i\succeq0$, the first part gives the brackets $\bigl(\begin{smallmatrix}A_i&B_i\\ B_i&A_i\end{smallmatrix}\bigr)\succeq0$, (b) tensorizes them, $\bigotimes_iB_i$ is self-adjoint, and the first part applies again. The two-factor identity is expanded directly, and each summand on its right is a tensor product of positive semidefinite operators. Finally $0\preceq A_i\preceq A_i'$ gives $A_i'\pm A_i\succeq0$. \end{proof} \emph{Brackets of measures.} For finite signed measures $\kappa,\kappa',\zeta$ on $\mathcal X^V$ and a cut $\vartheta$ we write $\bigl(\begin{smallmatrix}\kappa&\zeta\\ \zeta^*&\kappa'\end{smallmatrix}\bigr)\succeq_\vartheta0$, a \emph{bracket at $\vartheta$}, if the block matrix with blocks $C_\vartheta(\kappa)$, $C_\vartheta(\zeta)$, $C_\vartheta(\zeta)^{\mathsf T}$ (the block denoted $\zeta^*$; $\zeta^*$ is not a separate measure), $C_\vartheta(\kappa')$ is positive semidefinite. By (a), $|Q_\zeta(X,Y)|\le Q_\kappa(X,X)^{1/2}Q_{\kappa'}(Y,Y)^{1/2}$ for all half-functions; by (b) and \eqref{eq:cc:kron}, brackets of the factors of product measures tensorize to a bracket of the products; and by (d), if $C_\vartheta(\zeta)$ is symmetric, then $\bigl(\begin{smallmatrix}\kappa&\zeta\\ \zeta&\kappa\end{smallmatrix}\bigr)\succeq_\vartheta0$ if and only if $\kappa\pm\zeta\succeq_\vartheta0$. \subsection{From one cut to all slots: the H\"older inequality}\label{subsec:pos:holder} Reflection positivity turns a quadratic-form inequality at one cut into a mixed inequality across all slots. We first prove the single-cut Cauchy--Schwarz step, then explain why a sorting sequence gives the signed H\"older inequality. The method comes from infrared and chessboard estimates in statistical mechanics \cite{FrohlichSimonSpencer76,DysonLiebSimon78,FrohlichLieb,FILS,GlimmJaffe87}; the same positive semidefinite formalism appears in graph-density inequalities and flag algebras \cite{ConlonLee,HatamiNorine11,Razborov07,LovaszGraphLimits12,BorgsChayesLovaszSosVesztergombi08}. We use only the finite cut-matrix form proved below. \begin{definition}[Folds; sorting sequences]\label{def:sorting} For a cut $\vartheta$ define $\phi^\vartheta_\pm\colon V\to V$ by $\phi^\vartheta_+(v)=v$ for $v\in V_+$ and $\phi^\vartheta_+(v)=\vartheta v$ for $v\in V_-$; and $\phi^\vartheta_-(v)=\vartheta v$ for $v\in V_+$ and $\phi^\vartheta_-(v)=v$ for $v\in V_-$. A finite sequence of cuts $\vartheta^1,\dots,\vartheta^T$ with chosen signs $s_t\in\{\pm\}$ is \emph{sorting} if $\phi^{\vartheta^T}_{s_T}\circ\dots\circ\phi^{\vartheta^1}_{s_1}$ is constant on $V$. \end{definition} \begin{lemma}[Cauchy--Schwarz at one cut]\label{lem:holder:one-cut} Suppose $\nu$ is reflection positive at $\vartheta$. Then for every assignment $h\colon V\to\R^{\mathcal X}$, \begin{equation}\label{eq:cs-cut} |\Lambda_\nu(h)|^2\le\Lambda_\nu(h\circ\phi^\vartheta_+)\, \Lambda_\nu(h\circ\phi^\vartheta_-),\qquad \Lambda_\nu(h\circ\phi^\vartheta_\pm)\ge0 . \end{equation} In particular $\Lambda_\nu(g)\ge0$ for a constant assignment. \end{lemma} \begin{proof} Put $F(x)=\prod_{u\in V_+}h(u)(x_u)$ and $G(x)=\prod_{u\in V_+}h(\vartheta u)(x_u)$ for $x\in\mathcal X^{V_+}$. By \eqref{eq:cc:bilinear}, $\Lambda_\nu(h)$ is the cut form of $\nu$ at $(F,G)$, and its values at $(F,F)$ and $(G,G)$ are $\Lambda_\nu(h\circ\phi^\vartheta_+)$ and $\Lambda_\nu(h\circ\phi^\vartheta_-)$: the first folded assignment puts $h(u)$ at $u$ and at $\vartheta u$, the second puts $h(\vartheta u)$ at both ($u\in V_+$). Cauchy--Schwarz for the positive semidefinite form of $C_\vartheta(\nu)$ gives \eqref{eq:cs-cut}. For a constant assignment $F=G$. \end{proof} \begin{theorem}[Signed H\"older inequality]\label{thm:holder} Let $\nu$ be a finite signed measure on $\mathcal X^V$ that is RP at every cut of a sorting sequence. Then for all real functions $g$, $g_v$ on $\mathcal X$, \[ \Lambda_\nu(g)\ge0\qquad\text{and}\qquad \big|\Lambda_\nu\big((g_v)_{v\in V}\big)\big|\le\prod_{v\in V}\Lambda_\nu(g_v)^{1/d}. \] \end{theorem} \begin{proof} By \cref{lem:holder:one-cut}, diagonal values are nonnegative. Fix real functions $f_1,\dots,f_k$ and let $M=\max_h|\Lambda_\nu(h)|$ over the assignments $h\colon V\to\{f_1,\dots,f_k\}$. If $M>0$, let $h$ attain it. Both folded assignments again take values in $\{f_i\}$, so by \eqref{eq:cs-cut} they are nonnegative, at most $M$, and have product at least $M^2$. Hence both equal $M$: folds of maximisers are maximisers. Applying the folds in the order $\vartheta^T,\vartheta^{T-1},\dots,\vartheta^1$ turns $h$ into $h\circ\phi^{\vartheta^T}_{s_T}\circ\dots\circ\phi^{\vartheta^1}_{s_1}$, which is a constant maximiser. Therefore $M=\max_i\Lambda_\nu(f_i)$, which also holds when $M=0$. For $\epsilon>0$ apply this to $f_v=g_v/(\Lambda_\nu(g_v)+\epsilon)^{1/d}$, which satisfy $\Lambda_\nu(f_v)\le1$. Multilinearity gives $|\Lambda_\nu((g_v))|\le\prod_v(\Lambda_\nu(g_v)+\epsilon)^{1/d}$; let $\epsilon\downarrow0$. \end{proof} The proof uses only reflection positivity at the cuts of the sequence; it does not use that $\nu$ is nonnegative or normalized. Recall that a \emph{seminorm} is a nonnegative, absolutely homogeneous function satisfying the triangle inequality; it may vanish on nonzero vectors. \begin{corollary}[Seminorm]\label{cor:seminorm} Under the hypotheses of \cref{thm:holder}, $\|g\|_\nu=\Lambda_\nu(g)^{1/d}$ is a seminorm on $\R^{\mathcal X}$. If every one-slot marginal of $\nu$ is the uniform probability measure on $\mathcal X$, then $|\E_{x\in\mathcal X}g(x)|\le\|g\|_\nu$. \end{corollary} \begin{proof} Homogeneity holds because $d$ is even. For the triangle inequality, expand $\Lambda_\nu(g_1+g_2)$ into $2^d$ mixed terms and bound each by \cref{thm:holder}: \[ 0\le\Lambda_\nu(g_1+g_2)\le\sum_{S\subseteq V}\|g_1\|_\nu^{|S|}\|g_2\|_\nu^{d-|S|} =(\|g_1\|_\nu+\|g_2\|_\nu)^d . \] For the mean, put $g$ in one slot and $1$ in the others; then $\Lambda_\nu(1)=1$ and the uniform marginal give $|\E g|=|\Lambda_\nu(g,1,\dots,1)|\le\|g\|_\nu\|1\|_\nu^{d-1}=\|g\|_\nu$. \end{proof} \begin{remark}[Domination at one cut]\label{rem:cc:mixed} Let $\mu$ satisfy the hypotheses of \cref{thm:holder}, let $\vartheta$ be a cut at which $\mu$ is RP (it need not belong to the sorting sequence), and let $D$ be a finite signed measure with a bracket $\bigl(\begin{smallmatrix}\mu&D\\ D^*&\mu\end{smallmatrix}\bigr)\succeq_\vartheta0$, for instance $0\preceq_\vartheta D\preceq_\vartheta\mu$ (\cref{lem:record:block-gram}(d)). With $F,G$ as in \eqref{eq:cc:bilinear}, \cref{lem:record:block-gram}(a) and \cref{thm:holder} for the two folded assignments, in which each $g_u$ with $u\in V_+$, respectively $u\in V_-$, occurs twice, give \[ |\Lambda_D((g_v)_v)|\le Q_\mu(F,F)^{1/2}Q_\mu(G,G)^{1/2} \le\prod_{v\in V}\Lambda_\mu(g_v)^{1/d}. \] The measure $D$ need not be positive, RP at any other cut, a product, or normalized, and no seminorm is attached to it; only the dominating law carries the H\"older inequality. Normalizing $D$ by its mass would in general destroy the domination, and we never do it. \end{remark} \subsection{The \texorpdfstring{$72$}{72} slots \texorpdfstring{$(\Z/6\Z)^2\times\{0,1\}$}{(Z/6Z)\textasciicircum 2 x \{0,1\}}, their symmetries, and the six queries}\label{subsec:slot-array} The slots of the functional are indexed by a product of reflection coordinates: two six-chamber coordinates and a two-point layer. A product of coordinates, each with its own cuts and its own sorting sequence, is sorted by the concatenation of the sequences, because folds of different coordinates commute; this is the reason for working with products. A chamber coordinate carries the rotation $\rot$, the relation $\Rel$ and the group $\mathcal G_6$ of chamber automorphisms defined below, which transport positivity from one chamber cut to the others. \begin{definition}[Reflection coordinates; the slot array]\label{def:slot-array} \leavevmode \begin{enumerate}[label=(\alph*)] \item A \emph{reflection coordinate} is a finite set with a family of cuts that contains a sorting sequence. For reflection coordinates $V^{(i)}$, $i\in\mathcal C$ (a finite index set), a cut $\vartheta$ of $V^{(i)}$ with plus half $V^{(i)}_+$ induces the cut $\vartheta^{[i]}$ of $V=\prod_{i\in\mathcal C}V^{(i)}$ that applies $\vartheta$ to the coordinate $v_i$ and fixes the other coordinates, with plus half $\{v:v_i\in V^{(i)}_+\}$; these are the \emph{cuts of the coordinate $i$}. \item The \emph{chamber coordinate} is $\Zsix$, whose elements are \emph{chambers}, with the \emph{rotation} $\rot(j)=j+2$ for even $j$ and $\rot(j)=j-2$ for odd $j$, the relation $\Rel(x,y)\Leftrightarrow y\in\{x,x+1,x-1,\rot(x)\}$, and, for $a\in\Zsix$, the \emph{chamber reflection} $\vartheta_a(j)=2a-1-j$ with plus half $H_a=\{a,a+1,a+2\}$; its family of cuts consists of the six \emph{chamber cuts} $(\vartheta_a,H_a)$, $a\in\Zsix$ (they are cuts by \cref{lem:slot-array}(i) and contain a sorting sequence by \cref{lem:slot-array}(ii)). A pair $(j,\rot j)$ is a \emph{$\rot$-step}. The plus fold of $\vartheta_a$ is $f_a$: $f_a(j)=j$ for $j\in H_a$ and $f_a(j)=\vartheta_a(j)$ otherwise. \item The \emph{layer} is $\{0,1\}$ with the single cut $\ell\mapsto1-\ell$ and plus half $\{0\}$; its plus fold $\ell\mapsto0$ is constant, so this cut is a sorting sequence. \item The \emph{slot array} is $V=\Zsix\times\Zsix\times\{0,1\}$, $d=|V|=72$, with slots $v=(u_0,u_1,\ell)$; the coordinates $0$ and $1$ are the \emph{chamber coordinates} and the coordinate $2$, with value $\ell$, is the \emph{layer}. The \emph{chamber cut} $\vartheta_{c,a}$ ($c\in\{0,1\}$, $a\in\Zsix$) is the cut of the coordinate $c$ induced by $\vartheta_a$. The \emph{reserved cut} is the cut of the layer, \[ \iota(u_0,u_1,\ell)=(u_0,u_1,1-\ell),\qquad V_+=\{\ell=0\},\qquad V_-=\iota V_+ . \] The \emph{family of cuts} of $V$ is $\mathfrak F=\{\vartheta_{c,a}:c\in\{0,1\},\ a\in\Zsix\}\cup\{\iota\}$: thirteen cuts, with seven distinct involutions, since $\vartheta_{a+3}=\vartheta_a$ with complementary halves (three involutions in each chamber coordinate, and $\iota$). At $\iota$ we write $C_\iota$, $\succeq_\iota$ and $Q_\kappa$ for the cut matrix, the cut order and the cut form (\cref{def:cc:order}). \item The \emph{queries} are the six ordered pairs of slots \[ e^{(j)}=\big((0,j,0),\,(\rot0,\rot j,1)\big)=\big((0,j,0),\,(2,\rot j,1)\big), \qquad j\in\Zsix, \] forming the family $\mathcal E_6$. For $e=(u_e,v_e)\in\mathcal E_6$, $u_e$ is the \emph{source} and $v_e$ the \emph{target}. \end{enumerate} \end{definition} \begin{lemma}[The slot array]\label{lem:slot-array} \leavevmode \begin{enumerate}[label=(\roman*)] \item \emph{Chamber geometry and transport.} Each $\vartheta_a$ is a fixed-point-free involution of $\Zsix$ commuting with $\rot$, with $\vartheta_a(H_a)=\Zsix\setminus H_a$; moreover $\vartheta_{a+3}=\vartheta_a$ and $H_{a+3}=\Zsix\setminus H_a$, so $\vartheta_{c,a+3}$ is $\vartheta_{c,a}$ with its halves exchanged. The \emph{chamber automorphisms}, the permutations $\alpha$ of $\Zsix$ with $\alpha\circ\rot=\rot\circ\alpha$ and $\Rel(\alpha x,\alpha y)\Leftrightarrow\Rel(x,y)$, form a group $\mathcal G_6$ of order $6$: the translations $j\mapsto j+2k$ ($k=0,1,2$) and the reflections $\vartheta_0,\vartheta_1,\vartheta_2$. For $a\in\Zsix$ the element $\alpha_a\in\mathcal G_6$ given by $\alpha_a(j)=j-a$ for even $a$ and $\alpha_a(j)=a+2-j$ for odd $a$ satisfies $\alpha_a(H_a)=H_0$ and $\alpha_a\vartheta_a\alpha_a^{-1}=\vartheta_0$. There is exactly one bijection $H_a\to H_0$ that preserves $\Rel$ (the \emph{half isomorphism} of $H_a$); it is the restriction of every $\alpha\in\mathcal G_6$ with $\alpha(H_a)=H_0$, and it maps the unique $\rot$-step inside $H_a$ to $(0,2)$. \emph{Transport:} let $V=\prod_{i\in\mathcal C}V^{(i)}$ be a product of reflection coordinates whose coordinate $c$ is a chamber coordinate (for instance $\Zsix$ itself, $\Zsix\times\{0,1\}$, or the slot array with $c\in\{0,1\}$), write $\vartheta_{c,a}$ for the cut of the coordinate $c$ induced by $\vartheta_a$, and for $\alpha\in\mathcal G_6$ let $\alpha^{(c)}$ be the permutation of $V$ that applies $\alpha$ to the coordinate $c$. If a finite signed measure $\kappa$ on $\mathcal X^V$ is invariant under $\alpha_a^{(c)}$, then $C_{\vartheta_{c,a}}(\kappa)=S_aC_{\vartheta_{c,0}}(\kappa)S_a^{\mathsf T}$ for the permutation matrix $S_a$ of the bijection $x\mapsto(x_{\alpha_a^{(c)}u})_u$ of half-labellings; so a lower bound $C_{\vartheta_{c,0}}(\kappa)\succeq Q$ gives $C_{\vartheta_{c,a}}(\kappa)\succeq S_aQS_a^{\mathsf T}$, and $\kappa\succeq_{\vartheta_{c,0}}\kappa'$ implies $\kappa\succeq_{\vartheta_{c,a}}(\alpha_a^{(c)})_*\kappa'$. In particular a measure invariant under $\mathcal G_6$ acting on the coordinate $c$ that is RP at $\vartheta_{c,0}$ is RP at every chamber cut of the coordinate $c$; and on the slot array a measure invariant under $\mathcal G_6$ acting on each chamber coordinate that is RP at $\vartheta_{0,0}$, $\vartheta_{1,0}$ and $\iota$ is RP at every cut of $\mathfrak F$. \item \emph{Folds.} $f_0=(0,1,2,2,1,0)$ and $f_4=(0,0,5,4,4,5)$ (values at $0,\dots,5$), and $f_0\circ f_4\circ f_0$ is the constant map $0$; so $(\vartheta_0,\vartheta_4,\vartheta_0)$, all with sign $+$, is a sorting sequence of $\Zsix$. The minus fold of $\vartheta_a$ is $f_{a+3}$; in particular $f_4$ is the plus fold of $\vartheta_4$, the involution $\vartheta_1=\vartheta_4$ with plus half $H_4=\{4,5,0\}$. \item \emph{Products and sorting.} In a product $V=\prod_{i\in\mathcal C}V^{(i)}$ of reflection coordinates every induced cut is a cut; its folds act on its own coordinate by the folds of the factor and fix the other coordinates; reflections and folds of cuts of different coordinates commute; and every interleaving of sorting sequences of the factors that keeps the order within each factor is a sorting sequence of $V$. For the slot array, $\iota$ is a cut, every chamber reflection and chamber fold commutes with $\iota$ and its folds, the seven-step sequence \[ \vartheta_{0,0},\ \vartheta_{0,4},\ \vartheta_{0,0},\ \vartheta_{1,0},\ \vartheta_{1,4},\ \vartheta_{1,0},\ \iota, \] all with sign $+$, maps every slot to $(0,0,0)$, and $\mathfrak F$ consists of seven distinct involutions. Consequently a finite signed measure $\nu$ on $\mathcal X^V$ that is RP at the cuts of this sequence satisfies \cref{thm:holder,cor:seminorm} with $d=72$; if its one-slot marginals are uniform probabilities, $(\E g)^{72}\le\Lambda_\nu(g)$ whenever $\E g\ge0$, which is $\alpha^{72}\le Y$ for the functional (\cref{lem:record:holder}(e)). \item \emph{Queries.} The twelve endpoints of the six queries are distinct; every source lies in $V_+$ and every target in $V_-$; the reflected targets $\iota v_e=(2,\rot j,0)$ lie in $V_+$; and the twelve slots $u_e$, $\iota v_e$ ($e\in\mathcal E_6$) of $V_+$ are distinct. Each query applies $\rot$ to both chamber coordinates and flips the layer. \item \emph{Cylinder pullback.} Let $V=\prod_{i\in\mathcal C}V^{(i)}$ be a product of reflection coordinates, $\emptyset\ne\mathcal C'\subseteq\mathcal C$ a set of \emph{active} coordinates, $W=\prod_{i\in\mathcal C'}V^{(i)}$ with the induced cuts, and $\pi\colon V\to W$ the projection. The \emph{pullback} $\rho^*$ of a finite signed measure $\rho$ on $\mathcal X^W$ is its image under $\zeta\mapsto\zeta\circ\pi$: the slot $v$ receives the label of $\pi(v)$. \begin{enumerate}[label=(\alph*)] \item \emph{Inactive cuts.} If $\vartheta$ is a cut of a coordinate $i\notin\mathcal C'$, every $\zeta\circ\pi$ lies in $\operatorname{Fix}(\vartheta^{[i]})$; so every nonnegative measure supported on such labellings, for instance the pullback of any nonnegative measure on $\mathcal X^W$, is diagonal at $\vartheta^{[i]}$ and has a nonnegative diagonal cut matrix there (\cref{lem:commoncut}(i)). \item \emph{Active cuts.} If $\vartheta$ is a cut of a coordinate $i\in\mathcal C'$, then $\zeta\mapsto\zeta\circ\pi$ is half-local for the cuts induced by $\vartheta$ on $W$ and on $V$ (\cref{lem:commoncut}(v)); so an inequality $\rho_1\succeq\rho_2$ at the cut of $W$ gives $\rho_1^*\succeq\rho_2^*$ at the cut of $V$, and in particular reflection positivity passes from $\rho$ to $\rho^*$. \item \emph{Marginals.} For $u,v\in V$ the law of $(z_u,z_v)$ under $\rho^*$ is the law of $(\zeta_{\pi u},\zeta_{\pi v})$ under $\rho$. \item \emph{Equivariance.} If $\rho$ is invariant under $\zeta\mapsto(g(\zeta_w))_w$ for a bijection $g$ of $\mathcal X$, then $\rho^*$ is invariant under $z\mapsto(g(z_v))_v$. \end{enumerate} For the slot array and $\mathcal C'=\{0,2\}$ (a law on labels indexed by $(u_0,\ell)$), the cuts of the second chamber coordinate are inactive, and by (c) the ordered pair of labels at every query of $\mathcal E_6$ under the pullback $\rho^*$ has the law of the single ordered pair at the slots $(0,0)$ and $(2,1)$ of $\Zsix\times\{0,1\}$ under the original law $\rho$. \end{enumerate} \end{lemma} \begin{proof} (i) $\vartheta_a(\vartheta_a(j))=2a-1-(2a-1-j)=j$. A fixed point would satisfy $2j\equiv2a-1\pmod6$, which is impossible because $2j-2a+1$ is odd. For $i\in\{0,1,2\}$, $\vartheta_a(a+i)=a-1-i$, so $\vartheta_a(H_a)=\{a-1,a-2,a-3\}=\Zsix\setminus H_a$; and $\vartheta_{a+3}(j)=2a+5-j\equiv\vartheta_a(j)$, $H_{a+3}=\{a+3,a+4,a+5\}=\Zsix\setminus H_a$. The map $\vartheta_a$ reverses parity. For even $j$, $\vartheta_a(j)$ is odd and $\rot(\vartheta_a(j))=2a-3-j=\vartheta_a(j+2)=\vartheta_a(\rot j)$; for odd $j$, $\rot(\vartheta_a(j))=2a+1-j=\vartheta_a(j-2)=\vartheta_a(\rot j)$. \emph{Chamber automorphisms.} Let $\alpha$ be one. For every $x$, the elements $y\ne x$ with $\Rel(x,y)$ and $y\ne\rot(x)$ are $x\pm1$, because $\rot(x)=x\pm2$. Since $\alpha$ is a bijection commuting with $\rot$ and preserving $\Rel$, it maps this set for $x$ onto the set for $\alpha x$; so it preserves the hexagon adjacency $y=x\pm1$, and $\alpha$ is a rotation $j\mapsto j+k$ or a reflection $j\mapsto m-j$. A rotation commutes with $\rot$ if and only if $k$ is even: then it preserves parity and $\rot(j+k)=\rot(j)+k$, while for odd $k$, $\rot(k)=k-2\ne k+2=\rot(0)+k$. A reflection commutes with $\rot$ if and only if $m$ is odd: then it reverses parity and $\rot(m-j)=m-\rot(j)$, while for even $m$, $\rot(m)=m+2\ne m-2=m-\rot(0)$. The odd values $m=2a-1$ give $\vartheta_0,\vartheta_1,\vartheta_2$. Conversely these six maps commute with $\rot$ and change the differences $y-x\in\{0,\pm1\}$ at most by a sign, so they preserve $\Rel$, and so do their inverses. The chamber automorphisms form a group by definition; it has these six elements. \emph{The elements $\alpha_a$.} For even $a$, $\alpha_a$ is a translation by an even number, $\alpha_a(H_a)=H_0$, and $\alpha_a\vartheta_a\alpha_a^{-1}(j)=2a-1-(j+a)-a=-1-j=\vartheta_0(j)$. For odd $a$, $\alpha_a$ is the reflection $j\mapsto m-j$ with $m=a+2$ odd, hence lies in $\mathcal G_6$; it is an involution with $\alpha_a(H_a)=\{2,1,0\}$, and $\alpha_a\vartheta_a\alpha_a(j)=a+2-\big(2a-1-(a+2-j)\big)=5-j=\vartheta_0(j)$. \emph{Half isomorphisms.} Restricted to $H_0=\{0,1,2\}$, the relation $\Rel$ holds on all ordered pairs except $(2,0)$: indeed $\rot(0)=2$, while $0\notin\{2,1,3,4\}$. So $(0,2)$ is the unique pair $(x,y)$ of $H_0$ with $\Rel(x,y)$ and not $\Rel(y,x)$, and it is the only $\rot$-step inside $H_0$ ($\rot(1)=5$ and $\rot(2)=4$ lie outside $H_0$). The automorphism $\alpha_a$ maps $H_a$ onto $H_0$ preserving $\Rel$ and $\rot$-steps, so $H_a$ also has a unique asymmetric pair, which is its unique $\rot$-step. A $\Rel$-preserving bijection $H_a\to H_0$ must map the asymmetric pair of $H_a$ to $(0,2)$ and therefore the third element to $1$. This proves uniqueness, and the restriction of every $\alpha\in\mathcal G_6$ with $\alpha(H_a)=H_0$ is such a bijection. \emph{Transport.} Let $\sigma=\alpha_a^{(c)}$. Since $\alpha_a^{-1}\vartheta_0\alpha_a=\vartheta_a$, we have $\sigma^{-1}\vartheta_{c,0}\sigma=\vartheta_{c,a}$, and $\sigma^{-1}\{v:v_c\in H_0\}=\{v:v_c\in\alpha_a^{-1}H_0\}=\{v:v_c\in H_a\}$ is the plus half of $\vartheta_{c,a}$. If $\sigma_*\kappa=\kappa$, then \cref{rem:cut-symmetries}(c) gives the relabelling of the cut matrix, and $\kappa\succeq_{\vartheta_{c,0}}\kappa'$ implies $\kappa=\sigma_*\kappa\succeq_{\vartheta_{c,a}}\sigma_*\kappa'$. For the last two assertions apply this with $\kappa'=0$ to each $a\in\Zsix$ and each chamber coordinate. (ii) For $f_0$: $H_0=\{0,1,2\}$ and $\vartheta_0(3,4,5)=(2,1,0)$. For $f_4$: $H_4=\{4,5,0\}$ and $\vartheta_4(j)=7-j\equiv1-j$, so $\vartheta_4(1,2,3)=(0,5,4)$. Hence \[ f_0(\Zsix)=\{0,1,2\},\qquad f_4(\{0,1,2\})=\{0,5\},\qquad f_0(\{0,5\})=\{0\}, \] and $f_0\circ f_4\circ f_0$ is the constant map $0$. The minus fold of $\vartheta_a$ maps $H_a$ by $\vartheta_a$ onto $H_{a+3}$ and fixes $H_{a+3}$; as $\vartheta_{a+3}=\vartheta_a$, it is the plus fold $f_{a+3}$ of $\vartheta_{a+3}$. (iii) An induced cut $\vartheta^{[i]}$ is a fixed-point-free involution because $\vartheta$ is one, and it maps $\{v:v_i\in V^{(i)}_+\}$ onto $\{v:v_i\in V^{(i)}_-\}$. If $v_i\in V^{(i)}_+$, then $v$ lies in the plus half and is fixed by the plus fold; otherwise the plus fold sends $v$ to $\vartheta^{[i]}v$, whose coordinate $i$ is $\vartheta(v_i)$. So the folds of $\vartheta^{[i]}$ replace $v_i$ by its fold and fix the other coordinates, and maps acting on different coordinates commute. In the composition of the folds of an interleaved sequence, the coordinate $i$ is changed only by the folds of the coordinate $i$, in their order, and their composition is constant on $V^{(i)}$; so the composition is constant on $V$. For the slot array the factor sequences are $(\vartheta_0,\vartheta_4,\vartheta_0)$ for both chamber coordinates, by (ii), and the single cut of the layer, whose plus fold $\ell\mapsto0$ is constant; $\iota$ is the cut of the layer. The induced involutions $\vartheta_{c,a}$ and $\vartheta_{c,a'}$ coincide if and only if $\vartheta_a=\vartheta_{a'}$, that is $2a\equiv2a'\pmod6$, that is $a'\in\{a,a+3\}$; involutions of different coordinates differ; so $\mathfrak F$ consists of $3+3+1=7$ involutions. The last assertion is \cref{thm:holder,cor:seminorm}. (iv) The sources $(0,j,0)$ are six distinct slots with $u_0=0$ and $\ell=0$; the targets $(2,\rot j,1)$ are six distinct slots, since $\rot$ is a bijection, with $u_0=2$ and $\ell=1$. As $0\ne2$, the twelve endpoints are distinct. Sources lie in $V_+$ and targets in $V_-$, and $\iota v_e=(2,\rot j,0)\in V_+$; the slots $u_e$ and $\iota v_e$ are distinct, since their first coordinates are $0$ and $2$. The last sentence is the definition, with $\rot0=2$. (v) (a) If $i\notin\mathcal C'$, then $\vartheta^{[i]}v$ differs from $v$ only in the coordinate $i$, so $\pi(\vartheta^{[i]}v)=\pi(v)$ and $(\zeta\circ\pi)_{\vartheta^{[i]}v}=(\zeta\circ\pi)_v$. (b) Write $\vartheta_V$, $\vartheta_W$ for the cuts induced by $\vartheta$ on $V$ and on $W$, with plus halves $V_+$, $W_+$. Since $i\in\mathcal C'$, $\pi\circ\vartheta_V=\vartheta_W\circ\pi$, $\pi(V_+)\subseteq W_+$ and $\pi^{-1}(W_+)=V_+$. Put $\phi(\xi)=(\xi_{\pi v})_{v\in V_+}$ for $\xi\in\mathcal X^{W_+}$. For $z=\zeta\circ\pi$ we have $z_{V_+}=\phi(\zeta_{W_+})$ and $(z_{\vartheta_Vv})_{v\in V_+}=(\zeta_{\vartheta_W\pi v})_{v\in V_+} =\phi\big((\zeta_{\vartheta_Ww})_{w\in W_+}\big)$; so the pullback is the half-local map of $\phi$, and \cref{lem:commoncut}(v) applies. (c) and (d) are immediate from $z_v=\zeta_{\pi v}$. For the slot array with $\mathcal C'=\{0,2\}$, $\pi(0,j,0)=(0,0)$ and $\pi(2,\rot j,1)=(2,1)$. \end{proof} \begin{remark}\label{rem:slot-array-instances} Nothing in the transport of (i), in (iii) and in (v) depends on the particular factors. For instance the array $(\Zsix)^3$, with the nine-step sequence formed from $(\vartheta_0,\vartheta_4,\vartheta_0)$ in each of its three chamber coordinates, is sorted in the same way; Part~VI uses this array. \end{remark} \subsection{Square-affine invariance}\label{subsec:pos:invariance} Many laws below are invariant under relabelling all field elements at once by maps $x\mapsto rx+c$ with $r$ a square unit, chosen independently at each prime. Such a map acts only on the sampled field labels, not on the discrete choices in a record (which component or type was selected). Conditioning on a component or a type therefore preserves this invariance, while conditioning on a specified field label need not preserve it, and no invariance is claimed after such conditioning below. This subsection defines the invariance and lists the operations that preserve it. \begin{definition}[Square-affine invariance and pair law]\label{def:map:invariance} Let $\mathcal B$ be a finite set of odd primes with exponents $e_p\ge1$ ($p\in\mathcal B$), and $X_{\mathcal B}=\prod_{p\in\mathcal B}\Z/p^{e_p}\Z$. Let $\mathfrak G_{\mathcal B}$ be the group of maps $g=(g_p)_{p\in\mathcal B}$ of $X_{\mathcal B}$, $g(x)_p=r_px_p+c_p$, where $r_p$ is a square unit modulo $p^{e_p}$ and $c_p\in\Z/p^{e_p}\Z$, chosen \emph{independently} for each prime (for $e_p=1$: $r_p\in\Qsq$ and $c_p\in\Fp$). It acts on tuples $z\in X_{\mathcal B}^S$ ($S$ any finite index set) by $(gz)_s=g(z_s)$, the same $g$ for every index. A finite signed measure $\mu$ on $\Omega\times X_{\mathcal B}^S$, where the finite set $\Omega$ records discrete data fixed by the group (maps, component and type indices, tags), is \emph{square-affine invariant} if it is invariant under $(\omega,z)\mapsto(\omega,gz)$ for all $g\in\mathfrak G_{\mathcal B}$. If $e_p=1$ for every $p\in\mathcal B$, write $\Om[\mathcal B]=\prod_{p\in\mathcal B}\Om\subseteq X_{\mathcal B}^2$ (the pairs $(x,y)$ with $y_p-x_p\in\Qsq$ for every $p\in\mathcal B$); the \emph{product strict-square pair law} is the uniform probability on $\Om[\mathcal B]$, which is $\bigotimes_{p\in\mathcal B}\Unif(\Om)$. \end{definition} \begin{lemma}[Marginals and pair laws]\label{lem:marginals} Let $\mathcal B$ be as in \cref{def:map:invariance}. \begin{enumerate}[label=\textup{(\arabic*)}] \item\label{it:marg:closure} \emph{Invariance is preserved} by the following operations on square-affine invariant measures: sums and real multiples; normalization of a nonzero nonnegative measure; passing to the variation $|\mu|$; multiplication by a nonnegative function $\Phi(\omega,z)$ with $\Phi(\omega,gz)=\Phi(\omega,z)$ (for instance the restriction to an event defined by the latent record $\omega$ alone, or to injectivity at every prime, or, when $e_p=1$, a density that is a product of functions $\Ap(\pm(z_s-z_{s'})_p)$); images under $(\omega,z)\mapsto(\omega',z\circ\varsigma_\omega)$, where $\omega'$ is a function of $\omega$ and $\varsigma_\omega\colon S'\to S$ is a map of index sets depending on $\omega$ (including the cylinder pullback of \cref{lem:slot-array}(v), forgetting coordinates); products $\mu_1\otimes\mu_2$ of invariant measures over disjoint prime sets $\mathcal B_1,\mathcal B_2$ (as a measure over $\mathcal B_1\cup\mathcal B_2$, with latent record $(\omega_1,\omega_2)$); and mixtures $\sum_{\omega_0\in\Omega_0}\kappa(\omega_0)\,\delta_{\omega_0}\otimes\mu^{\omega_0}$ on $(\Omega_0\times\Omega)\times X_{\mathcal B}^S$ of invariant measures $\mu^{\omega_0}$ indexed by an additional latent variable $\omega_0$ with law $\kappa$ (for example a map shared by all primes of a block, drawn before the field labels, which are then independent across the primes). For a prime $p$ with $e_p=1$ and an oriented graph $G$, the uniform law on the injective strict-square labellings of $G$ over $\Fp$ (the law $\lambda_p(G)$ of \cref{def:graphs:labeling}) and the uniform law on all its strict-square labellings are invariant ($\mathcal B=\{p\}$). \item\label{it:marg:one} \emph{One-slot marginals.} If $\mu$ is an invariant finite signed measure on $\Omega\times X_{\mathcal B}^S$, then for every $s\in S$ and $\omega\in\Omega$ the measure $\mu(\{\omega\}\times\{z:z_s\in\cdot\})$ on $X_{\mathcal B}$ is $\mu(\{\omega\}\times X_{\mathcal B}^S)\,\Unif(X_{\mathcal B})$. In particular the one-slot marginals of $\mu$ and of $|\mu|$ are $\mu(1)\Unif(X_{\mathcal B})$ and $|\mu|(1)\Unif(X_{\mathcal B})$, where $\mu(1)$ is the total mass; and if $\mu$ is nonnegative, the law of $z_s$ under $\mu(\cdot\mid\omega)$ is uniform for every $\omega$ of positive mass. These conclusions need only invariance under the translations $(\omega,z)\mapsto(\omega,(z_s+c)_s)$, $c\in X_{\mathcal B}$. \item\label{it:marg:pair} \emph{Pair laws.} Suppose $e_p=1$ for every $p\in\mathcal B$. If $\mu$ is a nonzero nonnegative invariant measure, $s\ne s'$, and $\mu$-almost surely $(z_s,z_{s'})\in\Om[\mathcal B]$, then the law of $(z_s,z_{s'})$ under $\mu(\cdot\mid\omega)$, and under $\mu/\mu(1)$, is the product strict-square pair law $\Unif(\Om[\mathcal B])$. \end{enumerate} \end{lemma} \begin{proof} \ref{it:marg:closure} Each operation commutes with the action $(\omega,z)\mapsto(\omega,gz)$. For images, $(gz)\circ\varsigma_\omega=g(z\circ\varsigma_\omega)$ because $g$ acts slotwise; for products, $\mathfrak G_{\mathcal B_1\cup\mathcal B_2}=\mathfrak G_{\mathcal B_1}\times\mathfrak G_{\mathcal B_2}$ acts factorwise; for the variation, the image under the bijection $g$ of the Jordan decomposition $\mu=\mu_+-\mu_-$ is again a decomposition into mutually singular nonnegative measures, so by uniqueness $g$ preserves $\mu_\pm$ and $|\mu|$; the other cases are immediate, injectivity being preserved because each $g_p$ is a bijection. The uniform laws are invariant because $z\mapsto rz+c$ ($r\in\Qsq$) is a bijection of the respective sets of labellings: it multiplies every difference by a nonzero square and preserves injectivity. Functions $\Ap(\pm(z_s-z_{s'})_p)$ are invariant for the same reason. \ref{it:marg:one} The measure $\mu(\{\omega\}\times\{z:z_s\in\cdot\})$ is invariant under the translations $x\mapsto x+c$, $c\in X_{\mathcal B}$, which lie in $\mathfrak G_{\mathcal B}$ and act transitively on $X_{\mathcal B}$; so it gives the same mass to every point. Summing over $\omega$ gives the unconditional statement, and $|\mu|$ is invariant under the same translations by the Jordan argument of \ref{it:marg:closure}. Only the translations were used. \ref{it:marg:pair} $\mathfrak G_{\mathcal B}$ acts transitively on $\Om[\mathcal B]$: given $(x,y),(x',y')\in\Om[\mathcal B]$, put $g(w)_p=\frac{y'_p-x'_p}{y_p-x_p}(w_p-x_p)+x'_p$; the ratio is a quotient of nonzero squares, so $g\in\mathfrak G_{\mathcal B}$, and $g(x)=x'$, $g(y)=y'$. Conditioning on $\omega$ preserves invariance, so the law of $(z_s,z_{s'})$ under $\mu(\cdot\mid\omega)$ is an invariant probability on the finite set $\Om[\mathcal B]$, on which $\mathfrak G_{\mathcal B}$ acts transitively; hence it is uniform. Mixing over $\omega$ gives the statement for $\mu/\mu(1)$. Finally $\Om[\mathcal B]=\prod_p\Om$, so its uniform law is the product of the uniform laws of the factors. \end{proof} \subsection{Independent atoms: product laws and \texorpdfstring{$\alpha^{72}\le Y$}{alpha\textasciicircum 72 <= Y}}\label{subsec:pos:products} The reference law of the functional is a product of laws of independent atoms, finite sets of primes. The next lemma collects what the product inherits from its factors. An \emph{atom} is a finite set $\Blk$ of odd primes with exponents $e_p\ge1$; $X_\Blk=\prod_{p\in\Blk}\Z/p^{e_p}\Z$ carries its uniform probability measure. Let $V$ be a slot set with a family $\mathfrak F$ of cuts that contains a sorting sequence, $d=|V|$, and let $\mathcal A$ be a set of pairwise disjoint atoms, each with a measure $\mu_\Blk$ on $X_\Blk^V$. For a finite set $\mathcal S\subseteq\mathcal A$ put $X_{\mathcal S}=\prod_{\Blk\in\mathcal S}X_\Blk$, identify a family $(z_{v,\Blk})_{v\in V,\Blk\in\mathcal S}$ with $(z_v)_{v\in V}$, $z_v=(z_{v,\Blk})_\Blk\in X_{\mathcal S}$, and let \[ \mu_{\mathcal S}=\bigotimes_{\Blk\in\mathcal S}\mu_\Blk ,\qquad Z_{\mathcal S}(g)=\Lambda_{\mu_{\mathcal S}}(g)\quad(g\colon X_{\mathcal S}\to\R). \] For $\mathcal S_1\subseteq\mathcal S$, $\E_{\mathcal S_1}g$ is the uniform average of $g$ over the coordinates of the atoms of $\mathcal S_1$: $\E_{\mathcal S_1}g(x)=\E_{y\in X_{\mathcal S_1}}g(x+y)$, with $y$ extended by $0$ at the other atoms. \begin{lemma}[Signed H\"older inequality, mean and averaging]\label{lem:record:holder} Suppose that every $\mu_\Blk$ is a probability measure on $X_\Blk^V$, reflection positive at every cut of $\mathfrak F$, and square-affine invariant (\cref{def:map:invariance}, for the primes of $\Blk$). Let $\mathcal S\subseteq\mathcal A$ be finite and let $g,g_v$ ($v\in V$) be real functions on $X_{\mathcal S}$. \begin{enumerate}[label=(\alph*)] \item $\mu_{\mathcal S}$ is a probability measure, RP at every cut of $\mathfrak F$. Hence $Z_{\mathcal S}(g)\ge0$, $|\Lambda_{\mu_{\mathcal S}}((g_v)_v)|\le\prod_vZ_{\mathcal S}(g_v)^{1/d}$, and $\|g\|_{\mathcal S}=Z_{\mathcal S}(g)^{1/d}$ is a seminorm. \item $\mu_{\mathcal S}$ is invariant under $\mathfrak G_{\mathcal S}=\prod_{\Blk\in\mathcal S}\mathfrak G_\Blk$; its one-slot marginals are $\Unif(X_{\mathcal S})$; and for $u,w\in V$ the law of $(z_u,z_w)$ is the product over $\Blk\in\mathcal S$ of the laws of $(z_{u,\Blk},z_{w,\Blk})$ under $\mu_\Blk$. Consequently $|\E_xg(x)|\le\|g\|_{\mathcal S}$. \item $\|g\circ\psi\|_{\mathcal S}=\|g\|_{\mathcal S}$ for every primewise map $\psi\in\mathfrak G_{\mathcal S}$, $\psi(z)_p=r_pz_p+c_p$. \item If $\mathcal S_1\subseteq\mathcal S$, then $Z_{\mathcal S}(\E_{\mathcal S_1}g)=Z_{\mathcal S\setminus\mathcal S_1}(\E_{\mathcal S_1}g) \le Z_{\mathcal S}(g)$. If $g$ depends only on the coordinates of the atoms of $\mathcal S_2\subseteq\mathcal S$, then $Z_{\mathcal S}(g)=Z_{\mathcal S_2}(g)$. \item If $\E_xg(x)=\alpha\ge0$, then $\alpha^d\le Z_{\mathcal S}(g)$. In particular, for the lift, the inputs and the functional of \cref{def:record:functional} (with $\mathcal S=\mathcal A_N$, $d=72$, and $I,D_0,s$ as there), \[ \E_{z\in G_N}g^{I,D_0,s}(z)=\frac{D_0\,\#\{n\in A\cap I:\ n\equiv s\ (D_0)\}}{|I|}, \] so $\E F_A=\alpha:=|A|/N$ and $\alpha^{72}\le\Yf(\Lsc,A)$. \end{enumerate} \end{lemma} \begin{proof} (a) A product of probability measures is a probability measure. At a cut $\vartheta\in\mathfrak F$, $C_\vartheta(\mu_{\mathcal S})=\bigotimes_\Blk C_\vartheta(\mu_\Blk)$ by \eqref{eq:cc:kron}, a Kronecker product of symmetric positive semidefinite matrices. Since $\mathfrak F$ contains a sorting sequence, \cref{thm:holder} and \cref{cor:seminorm} apply; $d$ is even because $V$ has a cut. (b) The invariance is the product clause of \cref{lem:marginals}\ref{it:marg:closure}, and the one-slot marginals are uniform by \cref{lem:marginals}\ref{it:marg:one}. Under a product measure the coordinates of different factors are independent, and $(z_u,z_w)$ is the family of the pairs $(z_{u,\Blk},z_{w,\Blk})$. The mean bound is the second part of \cref{cor:seminorm}. (c) By (b), the map $(z_v)_v\mapsto(\psi(z_v))_v$ preserves $\mu_{\mathcal S}$. (d) $\E_{\mathcal S_1}g$ is the average of the translates $g(\cdot+y)$, $y\in X_{\mathcal S_1}$; by (c) with $r_p=1$ they all have seminorm $\|g\|_{\mathcal S}$, and the triangle inequality of (a) gives the inequality. The two equalities follow from Fubini, since the factors $\mu_\Blk$ are probability measures and the integrand does not depend on the labels of the atoms integrated out. (e) By (b), $\alpha\le\|g\|_{\mathcal S}$. For the lift, averaging over $z$ annihilates every nontrivial character, and the trivial character has conductor $1$, at most the cutoff $Q$ of the lift (\cref{sec:lifts}), so it is retained and the mean of $\mathcal L_{I,N}f$ is $\widehat f_I(0)=|I|^{-1}\sum_{n\in I}f(n)$. With $f=(D_0\one_{n\equiv s\,(D_0)}\one_A)|_I$ this is the stated number; with $I=[N]$ and $D_0=1$ it is $\alpha$. Apply the first part to $g=F_A$, for which $Z_{\mathcal A_N}(F_A)=\Yf(\Lsc,A)$. \end{proof} For the slot array and its family $\mathfrak F$ the hypotheses of the lemma are contained in \ref{it:record:R1}--\ref{it:record:R3} of \cref{hyp:record:reference}, which Part~V verifies atom by atom at every cut of $\mathfrak F$, not only at the sorting cuts (see the discussion after \cref{hyp:record:reference}). \paragraph{Consequences and what to read next.} Only linear algebra (the Loewner order of \cref{def:prelim:operators}, Kronecker products, polar decomposition, Cauchy--Schwarz and Jensen's inequality) and the arithmetic notation of \cref{sec:notation}: the nonzero squares $\Qsq$, the strict-square pairs $\Om$ and the indicator $\Ap$. Later definitions are named only as examples or applications: the laws $\lambda_p(G)$ (\cref{def:graphs:labeling}) in \cref{lem:marginals}, the coupled index (\cref{def:hyb:coupled}) in \cref{rem:cc:limits}, and the lift, the functional and the reference hypotheses (\cref{def:record:functional,hyp:record:reference}) in and after \cref{lem:record:holder}(e). No property of square-difference-free sets is used in this section. \space % End sections/05_positivity % Begin sections/06_lifts_sectors \section{The functional \texorpdfstring{$Y$}{Y}: Fourier truncation and estimates preserving the density} \label{sec:lifts} \paragraph{What this section proves and how to read it.} This section defines $Y=\Yf(\Lsc,A)$, the $72$-fold average of a truncated Fourier series $F_A$ of $\one_A$ (the \emph{lift}: $F_A$ retains characters of conductor at most $N^{1/20}$ so that fixing labels can be analysed prime by prime), and proves three properties used throughout: averaging interval-and-residue inputs returns $F_A$ exactly; $L^{2r}$ norms of lifts are linear in the density $\alpha$ (so remainders in \cref{sec:scale-comparison} are $O(\Lsc^{-\sigma} \alpha)$ with $\sigma=1/825$ (\cref{def:record:analytic-stage})); and Fourier terms of large conductor are damped at large primes. It also proves that tensor products preserve exact Fourier support (the resulting orthogonal components of a function, indexed by exact Fourier support, are called \emph{sectors}; they are not prime pieces; a \emph{spectator} is a factor left unchanged in such a tensor product). Inputs: \cref{sec:positivity} and the reference hypotheses (R1)--(R5) (\cref{subsec:lifts:reference}), verified in Part~V. Outputs: the definition \cref{def:record:functional} and the moment and decay estimates cited in Parts~III and~V. A first reading should follow the definition and the statements of the moment and decay results; the tensor-product linear algebra can be used as reference. (R4) uses \emph{mixing} (damping of nonconstant functions at large primes, \cref{def:mixing} below) and (R5) uses the forcing terminology of \cref{subsec:intro:glossary}. \subsection{Definition of the lift \texorpdfstring{$F_A$}{F\_A} and the functional \texorpdfstring{$Y(\Lsc,A)$}{Y(L,A)}}\label{subsec:lifts:functional} The slot array is $V=(\Z/6\Z)^2\times\{0,1\}$ of \cref{def:slot-array}, $d=|V|=72$, with the family $\mathfrak F$ of its cuts: the chamber cuts $\vartheta_{c,a}$ of the two chamber coordinates and the reserved cut $\iota$. The family contains a sorting sequence (\cref{def:sorting}, \cref{lem:slot-array}(iii)). The multilinear averages $\Lambda_\kappa((g_v)_v)$ and $\Lambda_\kappa(g)$ of a finite signed measure $\kappa$ on $X^V$ are those of \cref{sec:positivity}. \begin{definition}[The functional]\label{def:record:functional} Let $\beta=1/20$, let $\Kint\ge2$ be a fixed integer, and let $Q_3=19951586$, $\Pfour=2^{512}$ and $\Pfive=2^{65536}$. Put \[ \mathcal P_1=\{p<\Pfour:\ p\equiv1\ (\mathrm{mod}\ 4)\},\qquad \mathcal P_3=\{Q_3\le p<\Pfour:\ p\equiv3\ (\mathrm{mod}\ 4)\}, \] fix integers $m_p\ge1$ for $p\in\mathcal P_1$, and put $e_p=2m_p$ for $p\in\mathcal P_1$ and $e_p=1$ for every other prime. For a finite set $\mathcal S$ of primes let $X_{\mathcal S}=\prod_{p\in\mathcal S}\Z/p^{e_p}\Z$, with its uniform probability measure, and call $D_{\mathcal S}=|X_{\mathcal S}|=\prod_{p\in\mathcal S}p^{e_p}$ its \emph{full order}. \begin{enumerate}[label=(\alph*)] \item \emph{Scales.} For an integer $\Lsc\ge1$ put $N=\Kint\Lsc$, $Q=N^\beta$, $\mathcal T_N=\{p\ \text{prime}:\ \Pfour\le p\le N^\beta\}$, $\mathcal P_N=\mathcal P_1\cup\mathcal P_3\cup\mathcal T_N$ and $G_N=X_{\mathcal P_N}$. \item \emph{Characters.} A character of $X_{\mathcal S}$ is $z\mapsto e(z\cdot\xi)$ with $\xi=\sum_{p\in\mathcal S}a_p/p^{e_p}\in\Q/\Z$, $a_p\in\Z/p^{e_p}\Z$, and $z\cdot\xi=\sum_pa_pz_p/p^{e_p}$; we identify it with $\xi$. Its \emph{exact support} is $\{p:a_p\ne0\}$, and its \emph{conductor} $q(\xi)$ is the reduced denominator of $\xi$, that is, $q(\xi)=\prod_pp^{e_p-\min(v_p(a_p),e_p)}$, the product over $p\in\mathcal S$, with $a_p$ represented by an integer between $0$ and $p^{e_p}-1$ and $v_p(0)$ taken as $+\infty$. For $n\in\Z$ the number $e(n\xi)$ is well defined. The Fourier coefficient of $G\colon X_{\mathcal S}\to\C$ is $\widehat G(\xi)=\E_zG(z)e(-z\cdot\xi)$. \item \emph{Lift.} For a nonempty interval $I$ of integers and $f\colon I\to\C$ put \[ \widehat f_I(\xi)=\frac1{|I|}\sum_{n\in I}f(n)e(-n\xi)\quad(\xi\in\Q/\Z), \qquad \mathcal L_{I,N}f(z)=\sum_{\xi\in\Xi_N}\widehat f_I(\xi)\,e(z\cdot\xi)\quad(z\in G_N), \] where $\Xi_N$, the set of \emph{retained characters}, consists of the characters $\xi$ of $G_N$ with $q(\xi)\le Q$. It is defined by the \emph{total} conductor and depends neither on $I$ nor on $f$. It contains every character supported on the prefix coordinates ($p\in\mathcal P_1$) of conductor $p^j\le Q$, $1\le j\le e_p$, and it is closed under negation, so the lift of a real function is real. \item \emph{Atoms and reference laws.} The set $\mathcal A_N$ of \emph{atoms} at scale $N$ consists of the clique atoms $\{p\}$, $p\in\mathcal P_1$; the blocks of a fixed partition of $\mathcal P_3$ into finite sets (the middle blocks of \cref{def:record:exact-blocks} and the upper blocks of \cref{def:record:upper-bands}); and the tail atoms $\{p\}$, $p\in\mathcal T_N$. For an atom $\Blk$ we write $X_\Blk$ for $X_{\mathcal S}$ with $\mathcal S$ the set of primes of $\Blk$, and $\mu_\Blk$ for its reference law, a probability measure on $X_\Blk^V$ (constructed in Part~V; Parts~II and~III use only \cref{hyp:record:reference}). For a set $\mathcal S$ of atoms put $\mu_{\mathcal S}=\bigotimes_{\Blk\in\mathcal S}\mu_\Blk$ and $Z_{\mathcal S}(g)=\Lambda_{\mu_{\mathcal S}}(g)$ for $g\colon X_{\mathcal S}\to\R$; and $\mu_N=\mu_{\mathcal A_N}$, $Z_N=Z_{\mathcal A_N}$. \item \emph{Functional.} For $A\subseteq[N]$ let $F_A=\mathcal L_{[N],N}\one_A$ and $\Yf(\Lsc,A)=Z_N(F_A)$, and let $\Ym(\Lsc)$ be the maximum of $\Yf(\Lsc,A)$ over the square-difference-free sets $A\subseteq[N]$. \item \emph{Inputs.} For $b\in\Z/\Kint\Z$, identified with $\{1,\dots,\Kint\}$ through the least positive residues, let $I_b=((b-1)\Lsc,b\Lsc]\cap\Z$, and put $\mathcal I_\Lsc=\{[N],I_1,\dots,I_\Kint\}$. The intervals $I_b$ have length $\Lsc$ and partition $[N]$; every element of $I_b$ is smaller than every element of $I_{b+1}$ for $1\le b<\Kint$, and the shift $b\mapsto b+1$ wraps $I_\Kint$ to $I_1$. The \emph{small modulus} is $\Mzero=2^{2m_{\rm ext}+1}\prod_{3\le pQ$ then carries no nonconstant retained character. Two fixed integers control them, \[ Q_{\rm cl}=\prod_{p\in\mathcal P_1}p^{e_p},\qquad Q_{\rm pre}=Q_{\rm cl}\prod_{\substack{Q_3\le p<\Pfive\\ p\notin\mathcal P_1}}p , \] the full order of the clique prefix and a common multiple of the full orders of all atoms below $\Pfive$. The data $\Kint$ and $(m_p)_{p\in\mathcal P_1}$ are fixed, and constants may depend on them and on $\Mzero$, $Q_{\rm cl}$, $Q_{\rm pre}$ (\cref{rem:fixed-parameters}). The baseline uses $\Kint=\PushK$, and the main theorem uses $\Kint=\FourRoutesK$; both use $m_p=\mcl=8192$ at every $p\in\mathcal P_1$ (\cref{def:record:parameters}). \paragraph{Support components (``pieces'') of a lift.} Let $\mathcal P$ be a finite set of primes with $e_p=1$ for $p\in\mathcal P$, so that $X_{\mathcal P}=\prod_{p\in\mathcal P}\Fp$, and put $q_U=\prod_{p\in U}p$ for $U\subseteq\mathcal P$; a character of $X_{\mathcal P}$ with exact support $U$ has conductor $q_U$. For $f\colon I\to\C$ and $U\subseteq\mathcal P$, the \emph{piece of exact support $U$} of the lift of $f$ on $X_{\mathcal P}$ is $f_U(z)=\sum_\xi\widehat f_I(\xi)e(z\cdot\xi)$, the sum over the characters $\xi$ of $X_{\mathcal P}$ of exact support $U$. Each $f_U$ depends only on $z_U$ and has mean zero in every coordinate of $U$; if $f$ is real, so is $f_U$. The mean of a lift is its coefficient at $\xi=0$, $\E_z\mathcal L_{I,N}f(z)=\widehat f_I(0)=\E_If$, since $q(0)=1\le Q$. A lift of a nonnegative function can take negative values: all positivity in this paper comes from the reflection positivity of the laws, not from the inputs. \subsection{Assumptions (R1)--(R5) on the per-atom laws (proved in Part~V)}\label{subsec:lifts:reference} The analytic stage uses the following properties of the reference laws and of the factors of the comparison law, and nothing else about the local laws. \begin{hypothesis}[Reference atom laws]\label{hyp:record:reference} For every interval scale $\Lsc\ge1$, with $N=\Kint\Lsc$: \begin{enumerate}[label=(R\arabic*)] \item\label{it:record:R1} every $\mu_\Blk$ is a probability measure on $X_\Blk^V$, and the law of an atom does not depend on $N$; \item\label{it:record:R2} every $\mu_\Blk$ is reflection positive (\cref{def:rp}) at every cut of the family $\mathfrak F$, that is, at the chamber cuts of both chamber coordinates and at the reserved cut $\iota$; in particular at the seven cuts of the sorting sequence of \cref{lem:slot-array}; \item\label{it:record:R3} every $\mu_\Blk$ is square-affine invariant (\cref{def:map:invariance}): it is invariant under the simultaneous maps $z_{v,p}\mapsto r_pz_{v,p}+c_p$, where $r_p$ is a square unit and $c_p$ an element of $\Z/p^{e_p}\Z$, chosen independently for $p\in\Blk$; and every signed measure $\rho_\Blk$ on $X_\Blk^V$ that occurs in Parts~III and~V at $\Blk$ as a component, a replacement, a one-layer folded copy, or a difference of such measures, has a variation $|\rho_\Blk|$ whose one-slot marginals are all $|\rho_\Blk|(1)\Unif(X_\Blk)$. Both hold for every measure that is invariant under these maps, since the variation of an invariant measure is invariant; in particular every one-slot marginal of $\mu_\Blk$ is $\Unif(X_\Blk)$; \item\label{it:record:R4} for every tail prime $p\ge\Pfive$, with $\gamma=255/1024$: the law $\mu_p$ and its accepted part $\bar\nu_p=\nu_p/\nu_p(1)$, where $\nu_p$ is the factor at the one-prime atom $\{p\}$ of the comparison law $\nu$ of \cref{def:record:comparison-law} (at a tail prime the comparison law is nonnegative, \cref{lem:tail-prices}), are $(\gamma,v)$-mixing (\cref{def:mixing}) for every slot $v$; and for each query $(u,v)$ of the query family $\mathcal E_k$ of \cref{def:cp0}(c) (in Part~V, $\mathcal E_6$) the $(u,v)$-marginal of $\bar\nu_p$ is $\Unif(\Om)$ and $\bar\nu_p$ is $(\gamma,(u,v))$-mixing: its conditional operator from the pair $(u,v)$ to the other $70$ slots fixes constants, maps mean-zero functions to mean-zero functions and has norm at most $p^{-\gamma}$ on them; \item\label{it:record:R5} under every accepted part, that is every normalized component $\bar\nu_{\Blk,i}=\nu_{\Blk,i}/\nu_{\Blk,i}(1)$ of positive mass of the comparison law (\cref{def:record:comparison-law}) (components of mass zero are omitted), almost surely each query pair is a strict-square pair at every prime of $\Blk$ with $e_p=1$, and at a clique prime $p\in\mathcal P_1$ its difference is nonzero, of even valuation $2j0$ (an auxiliary exponent, not the exponent of the main theorem) there is $C_{r,\epsilon}$, depending only on $r$, $\epsilon$ and $Q_{\rm cl}$, with $\|G\|_{2r}^{2r}\le C_{r,\epsilon}Q^\epsilon M^{2r-2}\E_I|f|^2$. In particular, for $f=D_0\one_{n\equiv s\,(D_0)}\one_A$ on $I$ with $D_0\mid\Mzero$, the right-hand side is at most $C_{r,\epsilon}Q^\epsilon\Mzero^{2r}\alpha_I$, where $\alpha_I=|A\cap I|/|I|$. \end{enumerate} No division by $\E_I|f|^2$, $M$ or a density occurs; if $\E_I|f|^2=0$ then $G=0$. \end{lemma} The lift itself is such a piece: a character of $G_N$ is $\chi+\xi$ with $\chi$ a character of $X_{\mathcal P_1}$ and $\xi$ one of $X_{\mathcal P_3\cup\mathcal T_N}$, $q(\chi+\xi)=q(\chi)q(\xi)$ and $\widehat f_I(\chi+\xi)=\widehat{(f_\chi)}_I(\xi)$; so $\mathcal L_{I,N}f$ is the whole-support piece with $\mathcal S'=\mathcal P_1$, $\mathcal P=\mathcal P_3\cup\mathcal T_N$ and $\mathcal F_\chi=\{U:q(\chi)q_U\le Q\}$. \begin{proof} \emph{Step 1: the Gram bound.} The Fourier coefficient of $G$ at $\chi+\xi''$ is $0$ or $\widehat f_I(\chi+\xi'')$, and the characters with a nonzero coefficient are distinct elements of $\Q/\Z$ with reduced denominators at most $Q$; so Parseval and \cref{lem:lift:conditional-squares}(a) prove (a), as $1+Q^4/(2|I|)\le21/20$. Applied to $f_\chi$, whose modulus is that of $f$, with the cutoff $Q/q(\chi)$, the same argument gives for each $\chi$ \begin{equation}\label{eq:record:Echi} E_\chi:=\sum_{U\in\mathcal F_\chi}\|(f_\chi)_U\|_2^2\le\tfrac{21}{20}\E_I|f|^2 . \end{equation} \emph{Step 2: one prefix character.} Fix $\chi$ and write $h_U=(f_\chi)_U$, $S^2=\sum_{U\in\mathcal F_\chi}|h_U|^2$ and $T_j=\E S^{2j}$, so $T_1=E_\chi$. By \eqref{eq:cond-square} for $f_\chi$, with $\|f_\chi\|_\infty\le M$ and $|I|\ge10Q^6$, the hypothesis of \cref{lem:sqfun-rec} holds with $c=4M^2$; the case $j_0=1$ gives $T_r\le(2M)^{2r-2}2^{k(r^2+3r-4)/2}E_\chi$, because $(4M^24^k)^{r-1}2^{kr(r-1)/2}=(2M)^{2r-2}2^{k(r-1)(r+4)/2}$. The $h_U$ depend only on $z_U$ and have mean zero in each coordinate of $U$, so \cref{lem:lift:decoupling} gives \[ \Big\|\sum_Uh_U\Big\|_{2r}\le(k+1)(2eK_{2r})^k\,T_r^{1/(2r)} \le(k+1)(2eK_{2r})^k(2M)^{1-1/r}2^{k(r^2+3r-4)/(4r)}E_\chi^{1/(2r)} . \] \emph{Step 3: the prefix.} $|e(z'\cdot\chi)|=1$, and there are at most $D_{\mathcal S'}$ characters $\chi$. Minkowski over $\chi$, Step~2 and \eqref{eq:record:Echi} prove (b). \emph{Step 4: asymptotics.} A product of $k$ distinct primes is at least $(k+1)!$, so $(k+1)!\le Q$ and $k=O(\log Q/\log\log Q)$. Hence every factor of (b) that is exponential in $k$ is $Q^{o(1)}$ for fixed $r$, and $D_{\mathcal S'}\le Q_{\rm cl}$. Raising (b) to the power $2r$ gives the first part of (c). For $f=D_0\one_{n\equiv s}\one_A$ we have $M=D_0\le\Mzero$ and $\E_I|f|^2=D_0^2\#\{n\in A\cap I:n\equiv s\}/|I|\le\Mzero^2\alpha_I$. \end{proof} In \cref{sec:scale-comparison} the lemma is applied to the inputs on $G_N$, whose specializations at fixed labels on an arbitrary set of atoms are integrated over the labels by Fubini, $\E_{z_{\mathcal W}}\|G(z_{\mathcal W},\cdot)\|_s^s=\|G\|_s^s$ for every set $\mathcal W$ of coordinates and every $s\ge1$ (the fibres of a finite uniform product have equal mass); and to the lifts of rescaled sets on the complement of the selected atoms (\cref{lem:record:fibre-scale}(e)). A fixed label, without averaging, satisfies the explicit bound of the next corollary. \begin{corollary}[Conditional moments]\label{lem:record:conditional-moments} In the setting of \cref{lem:record:lift-moments}, let $\mathcal W\subseteq\mathcal P$, let $z_{\mathcal W}\in X_{\mathcal W}$, and fix arbitrary values on any subset of the coordinates of $X_{\mathcal S'}$; the bound below holds for every such choice. Then for every integer $r\ge1$, with $A_r=2eK_{2r}2^{(r+3)/4}$, \[ \|G(z_{\mathcal W},\cdot)\|_{2r}\le D_{\mathcal S'}\,2M\,3^{|\mathcal W|}(k+1)A_r^k, \] the norm being taken over the remaining coordinates with their uniform law. If $Q\le N^\beta$ and $q_{\mathcal W}\le N^{C_0}$ for a fixed $C_0$, the right-hand side is at most $C_{r,\epsilon}MN^\epsilon$ for every $\epsilon>0$, uniformly in the labels. \end{corollary} \begin{proof} Fixing prefix coordinates multiplies the term of $\chi$ by a unimodular constant or leaves it a function of the free prefix coordinates, so by Minkowski over $\chi$ it suffices to treat one $\chi$, with $h_U=(f_\chi)_U$. Group the supports by $U_0=U\cap\mathcal W$. For fixed $U_0$ the functions $h'_{U'}(y)=h_{U_0\cup U'}(z_{U_0},y)$, $U'\subseteq\mathcal P\setminus\mathcal W$, depend only on $y_{U'}$ and have mean zero in each coordinate of $U'$; for $W'\subseteq\mathcal P\setminus\mathcal W$ their conditional square sum over $U'\supseteq W'$ given $y_{W'}$ is part of the sum in \eqref{eq:cond-square} with pinned set $U_0\cup W'$, hence at most $4M^24^{|U_0|}4^{|W'|}$. \Cref{lem:sqfun-rec} with $c=4M^24^{|U_0|}$ and $j_0=0$, and \cref{lem:lift:decoupling}, give $\|\sum_{U'}h'_{U'}\|_{2r}\le2M2^{|U_0|}(k+1)A_r^k$. Summing over $U_0\subseteq\mathcal W$, with $\sum_{U_0}2^{|U_0|}=3^{|\mathcal W|}$, proves the bound. A product of $|\mathcal W|$ distinct primes is at least $(|\mathcal W|+1)!$, so $3^{|\mathcal W|}$ and the factors exponential in $k$ are $N^{o(1)}$. \end{proof} \begin{remark}[Averages and suprema over fibres]\label{rem:lift:fibres} The estimates of \cref{sec:scale-comparison} use only averaged moments. Averaging the fibre norms over $z_{\mathcal W}$ returns the full norm exactly. For a general function a single fixed fibre can be larger by the factor $q_{\mathcal W}^{1/s}$, the reciprocal of the $s$-th root of the fibre probability $q_{\mathcal W}^{-1}$: $\|G(z_{\mathcal W},\cdot)\|_s\le q_{\mathcal W}^{1/s}\|G\|_s$; for a lift a fixed label costs only $3^{|\mathcal W|}=N^{o(1)}$. This does not bound a pinned lift by a pinned density, and a pinned lift need not vanish on an empty fibre (\cref{rem:record:fibres}). \end{remark} \subsection{Tensor products preserve exact Fourier support}\label{subsec:lifts:sectors} A tensor product of operators that fix the constants on both sides preserves the orthogonal decomposition of a product space by exact nonconstant support, so its norm, the norm of a difference of two such products, and their symmetric and skew parts can be computed support by support. \paragraph{Setting.} Let $\mathcal K$ be a finite set. For $j\in\{0\}\cup\mathcal K$ let $(\Omega_j,\pi_j)$ and $(\Omega'_j,\pi'_j)$ be finite probability spaces, $L^2(\pi_j)$ the (real or complex) functions on the support of $\pi_j$, and $L^2_0(\pi_j)=\{f:\int f\,d\pi_j=0\}$; put $\Omega=\prod_j\Omega_j$, $\pi=\bigotimes_j\pi_j$ and $\pi'=\bigotimes_j\pi'_j$. The index $0$ is a \emph{spectator}, possibly a one-point space. For $S\subseteq\mathcal K$ the \emph{sector} of exact support $S$ is \[ H_S(\pi)=L^2(\pi_0)\otimes\bigotimes_{j\in S}L^2_0(\pi_j)\otimes \bigotimes_{j\in\mathcal K\setminus S}\C\one , \] and $X_S$ is the component of $X\in L^2(\pi)$ in $H_S(\pi)$, taken coordinatewise for maps into a finite-dimensional space. The sectors are mutually orthogonal and sum to $L^2(\pi)$, and for $W\subseteq\mathcal K$ the conditional expectation $\E_\pi[X\mid\omega_0,\omega_W]$ is the orthogonal projection onto $\bigoplus_{S\subseteq W}H_S(\pi)$, that is, it equals $\sum_{S\subseteq W}X_S$. A linear operator $T_j\colon L^2(\pi_j)\to L^2(\pi'_j)$ is \emph{sector-preserving} if $T_j\one=\one$ and $T_j^*\one=\one$. Then $T_j$ maps $L^2_0(\pi_j)$ into $L^2_0(\pi'_j)$, as $\ip{\one}{T_jf}=\ip{T_j^*\one}f=\ip{\one}f$; we write $T_j^\circ$ for this restriction and $\delta_j=\|T_j^\circ\|$ (this local $\delta_j$ is a norm, not one of the depth tails $\delta_{p,j}$). The Markov operator $T_jf(x')=\E[f(x)\mid x']$ of a coupling of $\pi'_j$ and $\pi_j$ (a probability measure on $\Omega'_j\times\Omega_j$ with these marginals) is sector-preserving, with $\delta_j\le1$, its maximal correlation; so is a doubly stochastic matrix on a finite set with the uniform law. The spectator operator $T_0\colon L^2(\pi_0)\to L^2(\pi'_0)$ is any linear operator. \begin{lemma}[Sector lemma]\label{lem:sector} In this setting let $T_j$ $(j\in\mathcal K)$ be sector-preserving and $T=T_0\otimes\bigotimes_{j\in\mathcal K}T_j$; put $\delta_S=\prod_{j\in S}\delta_j$. \begin{enumerate}[label=(\alph*)] \item\emph{Sectors.} $T$ maps $H_S(\pi)$ into $H_S(\pi')$ and equals $T_0\otimes\bigotimes_{j\in S}T_j^\circ\otimes\bigotimes_{j\notin S}1$ there, of norm $\|T_0\|\,\delta_S$; the same holds for $T^*$. Consequently, if $R$ is a linear combination of such tensor products and their adjoints, all acting between the same two spaces, then $R$ maps every sector into the corresponding sector and $\|R\|=\max_S\|R|_{H_S(\pi)}\|$; when $\pi'=\pi$ this applies to the symmetric and skew parts $\frac12(R\pm R^*)$, and an $n\times n$ operator matrix whose entries are such combinations maps every $H_S(\pi)\otimes\C^n$ into itself; it is positive semidefinite if and only if each of these restrictions is. \item\emph{Differences.} Let $T'_j$ $(j\in\mathcal K)$ be sector-preserving as well, with $\delta'_j=\|T'^\circ_j\|$, $\delta'_S=\prod_{j\in S}\delta'_j$, $\|T'^\circ_j-T^\circ_j\|\le d_j$ and $\max(\delta_j,\delta'_j)\le\kappa_j$, and $T'=T_0\otimes\bigotimes_jT'_j$. Then $T'-T$ vanishes on $H_\emptyset(\pi)$ and, on $H_S(\pi)$, \[ \|(T'-T)|_{H_S}\|\le\|T_0\|\min\Big(\sum_{j\in S}d_j\!\!\prod_{k\in S\setminus\{j\}}\!\!\kappa_k,\ \delta'_S+\delta_S\Big). \] Let moreover $\pi'=\pi$ and $T_0=I$. On $H_{\{j\}}$ the difference and its symmetric and skew parts are those of $T'^\circ_j-T^\circ_j$. If every $T_j$ is self-adjoint, the skew part of $T'-T$ on $H_S$ is that of $T'|_{H_S}$, of norm at most $\delta'_S$. If $d_j\le d$ and $\kappa_j\le\kappa\le1/2$ for all $j$, the first bound is at most $|S|d\kappa^{|S|-1}\le2d\kappa\le d$ for $|S|\ge2$; so if also $\|\mathrm{Sym}(T'_j-T_j)\|\le d_{\rm s}$ and $\|\mathrm{Skew}(T'_j-T_j)\|\le d_{\rm a}$ for all $j$, then \[ \|\mathrm{Sym}(T'-T)\|\le\max(d_{\rm s},2d\kappa),\qquad \|\mathrm{Skew}(T'-T)\|\le\max(d_{\rm a},2d\kappa),\qquad\|T'-T\|\le d . \] More generally, with $\pi'=\pi$ and $T_0=I$, the norms of $T'-T$ and of its symmetric and skew parts are the maxima over $S\ne\emptyset$ of the norms of their restrictions to $H_S$; on $H_{\{j\}}$ these restrictions are the corresponding parts of $T'^\circ_j-T^\circ_j$, and on $H_S$ with $|S|\ge2$ their norms are at most $\delta_S+\delta'_S$, which is at most $\delta_j\delta_k+\delta'_j\delta'_k$ for any $j\ne k$ in $S$ when all $\delta_i,\delta'_i\le1$. Hence, in that case, \[ \|\mathrm{Sym}(T'-T)\|\le\max\Bigl(\max_j\|\mathrm{Sym}(T'^\circ_j-T^\circ_j)\|,\ \max_{j\ne k}(\delta_j\delta_k+\delta'_j\delta'_k)\Bigr), \] the second maximum being $0$ if $|\mathcal K|=1$, and the same holds for $\mathrm{Skew}(T'-T)$ and for $T'-T$. \item\emph{Markov tensor maximum.} Let the spectator be trivial, $\mathcal K\ne\emptyset$, and $\delta_j\le1$ for all $j$ (for instance, Markov operators of couplings with exact marginals). Then $\|T-\Jproj\|=\max_j\delta_j$, where $\Jproj f=(\int f\,d\pi)\one$. If moreover $\pi'=\pi$ and each $T_j$ is self-adjoint with spectrum in $[-c_j,1]$, $0\le c_j\le1$, then $T\succeq-(\max_jc_j)I$. \item\emph{Random inclusion.} Let $\Jc\subseteq\mathcal K$ be a random set containing each $j$ independently with probability $\delta_j\in[0,1]$, where here the $\delta_j$ are any numbers (in the applications, bounds for the norms of (a)), and $\delta_S=\prod_{j\in S}\delta_j$. Let $E$ be a finite-dimensional space with a positive semidefinite Hermitian form $M$, and $\|Y\|_M^2=\int M(Y(\omega),Y(\omega))\,d\pi(\omega)$ for $Y\colon\Omega\to E$. Then components of different supports are orthogonal for this form, and for every $X\colon\Omega\to E$ \[ \E_\Jc\big\|\E_\pi[X\mid\omega_0,\omega_\Jc]\big\|_M^2=\sum_{S\subseteq\mathcal K}\delta_S\|X_S\|_M^2 . \] \item\emph{Exact-support decay.} For every $X\in L^2(\pi)$, $\|TX\|^2=\sum_S\|TX_S\|^2\le\|T_0\|^2\sum_S\delta_S^2\|X_S\|^2$. \item\emph{Product densities.} If the spectator is trivial and $\varphi_j\in L^2(\pi_j)$ with $\int\varphi_j\,d\pi_j=1$ $(j\in\mathcal K)$, then $\|\bigotimes_j\varphi_j-\one\|^2=\prod_j(1+\|\varphi_j-\one\|^2)-1$. \item\emph{Tensor spectrum} (no sector hypothesis). If $A_1,\dots,A_r$ are self-adjoint operators on finite-dimensional Hilbert spaces with spectra in $[-c_i,1+b_i]$, where $b_i\ge0$ and $0\le c_i\le1+b_i$, then the spectrum of $\bigotimes_iA_i$ lies in \[ \Big[-\max_i\Big(c_i\prod_{k\ne i}(1+b_k)\Big),\ \prod_i(1+b_i)\Big]; \] in particular $\bigotimes_iA_i\succeq-(\max_ic_i)\prod_i(1+b_i)I\succeq-(\max_ic_i)e^{\sum_ib_i}I$. \item\emph{Two supports.} Let $\pi'=\pi$, $T_0=I$, let $T_j$ and $T'_j$ be as in \textup{(b)} with every $T_j$ self-adjoint, and write $T'_j=T_j+S_j+A_j$ with $S_j=\mathrm{Sym}(T'_j-T_j)$ and $A_j=\mathrm{Skew}(T'_j-T_j)$, so that $T_j+S_j=\mathrm{Sym}\,T'_j$ and $A_j=\mathrm{Skew}\,T'_j$. Then $S_j$ and $A_j$ vanish on the constants and map $L^2_0(\pi_j)$ into itself, and on $H_{\{j,k\}}$, $j\ne k$, with the identity on the spectator and on the constants of the other coordinates, \begin{align*} \mathrm{Sym}(T'-T)&=T^\circ_j\otimes S^\circ_k+S^\circ_j\otimes T^\circ_k +S^\circ_j\otimes S^\circ_k+A^\circ_j\otimes A^\circ_k,\\ \mathrm{Skew}(T'-T)&=(T_j+S_j)^\circ\otimes A^\circ_k +A^\circ_j\otimes(T_k+S_k)^\circ; \end{align*} in particular the skew part of $T'-T$ on $H_{\{j,k\}}$ has norm at most $\|(T_j+S_j)^\circ\|\,\|A^\circ_k\|+\|A^\circ_j\|\,\|(T_k+S_k)^\circ\|$. \end{enumerate} \end{lemma} \begin{proof} \emph{The setting.} For $S\ne S'$ pick $j$ in the symmetric difference; on pure tensors the factors at $j$ are $\one$ and a function of mean zero, so $H_S\perp H_{S'}$. Expanding $L^2(\pi_j)=\C\one\oplus L^2_0(\pi_j)$ for $j\in\mathcal K$ shows that the sectors sum to $L^2(\pi)$ and that the functions of $(\omega_0,\omega_W)$ form $\bigoplus_{S\subseteq W}H_S$. (a) On a pure tensor $f_0\otimes\bigotimes_{j\in S}f_j\otimes\bigotimes_{j\notin S}\one$ with $f_j\in L^2_0(\pi_j)$, $T$ acts as $T_0f_0\otimes\bigotimes_{j\in S}T_j^\circ f_j\otimes\bigotimes_{j\notin S}\one\in H_S(\pi')$, and such tensors span $H_S(\pi)$; tensoring with $\C\one$ is isometric, and the norm of a tensor product of operators is the product of the norms. The adjoint $T^*=T_0^*\otimes\bigotimes_jT_j^*$ has the same form, each $T_j^*$ being sector-preserving with $(T_j^*)^\circ=(T_j^\circ)^*$. A combination $R$ is the orthogonal sum of its restrictions to the sectors, which are orthogonal on both sides; so is an operator matrix with such entries, on the spaces $H_S(\pi)\otimes\C^n$, and its quadratic form is the sum of theirs. (b) By (a), $T'-T$ is $T_0\otimes(\bigotimes_{j\in S}T'^\circ_j-\bigotimes_{j\in S}T^\circ_j)\otimes1$ on $H_S$, and $0$ on $H_\emptyset$, where both act as $T_0\otimes1$. Telescoping over an ordering $j_1,\dots,j_s$ of $S$, \[ \bigotimes_iT'^\circ_{j_i}-\bigotimes_iT^\circ_{j_i}=\sum_{i=1}^s T'^\circ_{j_1}\otimes\dots\otimes T'^\circ_{j_{i-1}}\otimes (T'^\circ_{j_i}-T^\circ_{j_i})\otimes T^\circ_{j_{i+1}}\otimes\dots\otimes T^\circ_{j_s}, \] of norm at most $\sum_id_{j_i}\prod_{k\ne j_i}\kappa_k$; the triangle inequality gives the second bound. With $T_0=I$ and $\pi'=\pi$, $T'-T$ and its adjoint preserve every $H_S$, so its symmetric and skew parts restrict to those of the restrictions; on $H_{\{j\}}$ the restriction is $T'^\circ_j-T^\circ_j$. If every $T_j$ is self-adjoint, so is $T|_{H_S}$, and the skew part of $(T'-T)|_{H_S}$ is that of $\bigotimes_{j\in S}T'^\circ_j$, of norm at most $\delta'_S$. For $s=|S|\ge2$, $sd\kappa^{s-1}=\kappa d\,s\kappa^{s-2}\le\kappa d\,s2^{2-s}\le 2d\kappa\le d$, and the three displayed bounds are the maxima over the sectors. For the final assertion of (b), (a) applies to the combinations $T'-T$, $\mathrm{Sym}(T'-T)$ and $\mathrm{Skew}(T'-T)$, whose restrictions to $H_S$ are $(T'-T)|_{H_S}$ and its two parts. On $H_S$ with $|S|\ge2$ the second bound of the display gives $\delta_S+\delta'_S$, and the symmetric and skew parts of an operator have norm at most its own; for $j\ne k$ in $S$ every factor of $\delta_S$ and of $\delta'_S$ other than those at $j$ and $k$ is at most one. (c) $\Jproj=\bigotimes_j\Jproj_j$, with $\Jproj_jf=(\int f\,d\pi_j)\one$, is a tensor product of sector-preserving operators with $\Jproj_j^\circ=0$; so it agrees with $T$ on $H_\emptyset$ and vanishes on the other sectors, and $T-\Jproj$ vanishes on $H_\emptyset$ and has norm $\delta_S\le\min_{j\in S}\delta_j$ on $H_S$, $S\ne\emptyset$, with equality at singletons; by (a) its norm is $\max_j\delta_j$. If each $T_j$ is self-adjoint with spectrum in $[-c_j,1]$, then on $H_S$ the operator $\bigotimes_{j\in S}T_j^\circ$ has eigenvalues $\prod_{j\in S}\lambda_j$, $\lambda_j\in[-c_j,1]$; a negative product has a negative factor $\lambda_i\ge-c_i$ and other factors of modulus at most one, so it is at least $-\max_jc_j$. On $H_\emptyset$ the operator is the identity. (d) For $X_S\in H_S\otimes E$, $X_{S'}\in H_{S'}\otimes E$ and $S\ne S'$, $\int M(X_S,X_{S'})\,d\pi=\sum_{a,b}M_{ab}\int\overline{X_{S,a}}X_{S',b}\,d\pi=0$ in a basis of $E$. Hence $\|\E[X\mid\omega_0,\omega_W]\|_M^2=\sum_{S\subseteq W}\|X_S\|_M^2$ for fixed $W$; averaging over $\Jc$ gives $\sum_S\Pr(S\subseteq\Jc)\|X_S\|_M^2$, and $\Pr(S\subseteq\Jc)=\delta_S$. (e) The images $TX_S$ lie in the orthogonal sectors $H_S(\pi')$, and $\|TX_S\|\le\|T_0\|\delta_S\|X_S\|$ by (a). (f) With $\varphi_j=\one+c_j$, $c_j\in L^2_0(\pi_j)$, $\bigotimes_j\varphi_j-\one=\sum_{S\ne\emptyset}\bigotimes_{j\in S}c_j\otimes \bigotimes_{j\notin S}\one$, the term of $S$ lying in $H_S$; by orthogonality the squared norm is $\sum_{S\ne\emptyset}\prod_{j\in S}\|c_j\|^2= \prod_j(1+\|c_j\|^2)-1$. (g) $\bigotimes_iA_i$ is self-adjoint with an orthonormal eigenbasis of product vectors and eigenvalues $\prod_i\lambda_i$, $\lambda_i\in[-c_i,1+b_i]$, so $|\lambda_i|\le1+b_i$. A product is at most $\prod_i(1+b_i)$, and a negative one has a negative factor $\lambda_i\ge-c_i$, so it is at least $-c_i\prod_{k\ne i}(1+b_k)$. Finally $1+b\le e^b$. (h) As $T_j$ and $T'_j$ are sector-preserving, $T'_j-T_j$ and its adjoint vanish on the constants, hence so do $S_j$, $A_j$ and their adjoints; and $\ip\one{S_jf}=\ip{S_j^*\one}f=0$, likewise for $A_j$, so both map $L^2_0(\pi_j)$ into itself. Thus $T'^\circ_j=T^\circ_j+S^\circ_j+A^\circ_j$ on $L^2_0(\pi_j)$, with $T^\circ_j$, $S^\circ_j$ self-adjoint and $A^\circ_j$ skew. By (a), $T'-T$ acts on $H_{\{j,k\}}$ as $T'^\circ_j\otimes T'^\circ_k-T^\circ_j\otimes T^\circ_k$, with the identity on the other factors. Put $U_j=(T_j+S_j)^\circ$ and $U_k=(T_k+S_k)^\circ$, both self-adjoint. The adjoint of $(U_j+A^\circ_j)\otimes(U_k+A^\circ_k)$ is $(U_j-A^\circ_j)\otimes(U_k-A^\circ_k)$, so its symmetric part is $U_j\otimes U_k+A^\circ_j\otimes A^\circ_k$ and its skew part is $U_j\otimes A^\circ_k+A^\circ_j\otimes U_k$. The operator $T^\circ_j\otimes T^\circ_k$ is self-adjoint; subtracting it and expanding $U_j\otimes U_k-T^\circ_j\otimes T^\circ_k$ gives the two identities. The norm bound follows from the triangle inequality and $\|X\otimes Y\|=\|X\|\,\|Y\|$. \end{proof} \begin{remark}[How the sector lemma is used]\label{rem:sector-uses} Part (c) is why the comparison records of Part~V keep their actual marginals: Markov operators of couplings with exact marginals, taken in those marginals, have centred norm equal to the \emph{maximum} of the centred norms of their factors under tensor products, not the sum or product of those norms. The maximal correlation of a product of couplings is the largest factor correlation. For self-adjoint Markov operators the product is bounded below by the minimum of zero and the smallest eigenvalues of its factors; if at least one factor has a negative eigenvalue, the smallest product eigenvalue equals the smallest factor eigenvalue. Operators normalized in a reference space are not Markov; when their factor spectra lie in $[-c_i,1+b_i]$, part (g) bounds every product eigenvalue above by $\prod_i(1+b_i)$ and below by $-\max_i c_i\prod_{k\ne i}(1+b_k)$ (\cref{lem:spec:tensorcomp}). Part (b) prices a block difference: on a support of at least two primes the difference of two products is of second order, and when the old operator is self-adjoint only the new one contributes to the skew part. Parts (a), (d) and (e) are the whole content of the index estimates (\cref{cor:index-support-frame}(i), \cref{lem:record:common-mean}) and of conductor decay; part (f) says that for a product density $\bigotimes_j(\one+c_j)$ the squared $L^2$ distance from $\one$ is $\prod_j(1+\|c_j\|^2)-1$. The closing clause of (b) prices a block whose prime differences have separate symmetric and skew coefficients (the upper comparisons of \cref{sec:upper-comparison}; for the signed fold records of \cref{sec:middle-records}, which are combinations of products, \cref{rem:signed-mixture-sectors} gives the same decomposition), and (h) is the two-prime step of the matching records, whose reference factor is self-adjoint (\cref{lem:oct24:matching-star}). \end{remark} \begin{remark}[Signed mixtures of products]\label{rem:signed-mixture-sectors} Let the spectator be trivial, let $T_{i,j}$ ($i$ in a finite index set, $j\in\mathcal K$) be sector-preserving, and put $K=\sum_ic_i\bigotimes_{j\in\mathcal K}T_{i,j}$ with real $c_i$, $\sum_ic_i=1$. By (a), $K$ maps every sector into the corresponding sector: it is the identity on $H_\emptyset$, it acts on $H_{\{j\}}$ as the combination $\sum_ic_iT^\circ_{i,j}$ at the single coordinate $j$, and on $H_S$ its norm is at most $\sum_i|c_i|\prod_{j\in S}\|T^\circ_{i,j}\|$. The difference of two such combinations decomposes in the same way: it vanishes on $H_\emptyset$, it is the difference of the two coordinate combinations on $H_{\{j\}}$, and on $H_S$ its norm is at most the sum of the two bounds; when $\pi'=\pi$, its symmetric and skew parts restrict to the sectors in the same way, with the same bound on $H_S$, and all these norms are maxima over the sectors. If the $T_{i,j}$ are the operators of couplings $\pi_{i,j}$ of $\pi'_j$ and $\pi_j$, then $K$ is the operator of the signed measure $\sum_ic_i\bigotimes_j\pi_{i,j}$, which has the marginals $\pi'$ and $\pi$ and total variation at most $\sum_i|c_i|$, whatever $|\mathcal K|$. A combination taken at every coordinate, $\bigotimes_j(\sum_ic_iT_{i,j})$, has the same marginals, but its total variation is the product of those of the coordinate combinations, for which only the bound $(\sum_i|c_i|)^{|\mathcal K|}$ is available. The fold records of the middle range are combinations of the first kind, of three products with $\sum_i|c_i|=1+\tlaw$ (\cref{def:record:mixture}). \end{remark} \subsection{Fourier terms of large conductor are damped at the mixing primes \texorpdfstring{$p\ge\Pfive$}{p >= P\_5}}\label{subsec:lifts:decay} A Fourier term supported on many prime coordinates is small after conditioning on the other slots, provided each such prime supplies a mixing factor. The orthogonality of distinct Fourier supports lets these factors multiply without counting the supports. Reflection positivity is not an assumption in this step. \begin{definition}[Conditional mixing]\label{def:mixing} Let $X$ be a finite set, $\rho$ a probability measure on $X^V$, and $Z\subseteq V$ a nonempty block of slots, with $\rho_Z$ the $\rho$-law of $z_Z$ and $\lambda$ the $\rho$-law of $z_{V\setminus Z}$. The \emph{conditional operator} from $Z$ to the other slots is $T^{\rho,Z}f(y)=\E_\rho[f(z_Z)\mid z_{V\setminus Z}=y]$, from $L^2(\rho_Z)$ to $L^2(\lambda)$; it fixes the constants, maps $\rho_Z$-mean-zero functions to $\lambda$-mean-zero functions and is a contraction. For a prime $p$ and $\gamma>0$, a probability measure $\rho$ on $\Fp^V$ is \emph{$(\gamma,Z)$-mixing} if $\|T^{\rho,Z}f\|_{L^2(\lambda)}\le p^{-\gamma} \|f\|_{L^2(\rho_Z)}$ for every $f$ with $\int f\,d\rho_Z=0$. For $Z=\{v\}$ we say \emph{$(\gamma,v)$-mixing} (when $\rho$ has uniform one-slot marginals, $\rho_{\{v\}}=\Unif(\Fp)$), and for a query pair $Z=\{u,v\}$, ordered as $(u,v)$, \emph{$(\gamma,(u,v))$-mixing}. \end{definition} \begin{lemma}[Mixtures]\label{lem:mixture} Let $Z$ and $Z'$ be finite sets and $\kappa=\sum_{i=1}^n\varpi_i\kappa_i$ with $\varpi_i>0$, $\sum_i\varpi_i=1$, where the $\kappa_i$ are probability measures on $Z\times Z'$ with the same $Z$-marginal $m$. Let $\kappa'$ and $\kappa'_i$ be the $Z'$-marginals, and $T^\kappa f(z')=\E_\kappa[f(z)\mid z']$, $T^{\kappa_i}$ likewise, for $f\in L^2(m)$. Then $T^\kappa f=\sum_ih_iT^{\kappa_i}f$ $\kappa'$-almost everywhere, with $h_i=\varpi_i\,d\kappa'_i/d\kappa'$ and $\sum_ih_i=1$, and \[ \|T^\kappa f\|^2_{L^2(\kappa')}\le\sum_i\varpi_i\|T^{\kappa_i}f\|^2_{L^2(\kappa'_i)} . \] Each $T^{\kappa_i}$, and $T^\kappa$, fixes the constants, is a contraction and maps $m$-mean-zero functions to mean-zero functions. Consequently, if $\|T^{\kappa_i}f\|\le c_i\|f\|$ for every $m$-mean-zero $f$, then $\|T^\kappa f\|^2\le\sum_i\varpi_ic_i^2\|f\|^2$: a mixture of $(\gamma,Z)$-mixing laws with a common $Z$-marginal is $(\gamma,Z)$-mixing, and a component of weight $\varpi$ costs at most $\varpi^{1/2}$ in the norm. \end{lemma} \begin{proof} For $z'$ with $\kappa'(z')>0$, $T^\kappa f(z')=\sum_zf(z)\kappa(z,z')/\kappa'(z')=\sum_i(\varpi_i\kappa'_i(z')/ \kappa'(z'))\,T^{\kappa_i}f(z')$, the terms with $\kappa'_i(z')=0$ being absent. By convexity $|T^\kappa f|^2\le\sum_ih_i|T^{\kappa_i}f|^2$ pointwise, and $\int h_i|T^{\kappa_i}f|^2\,d\kappa'=\varpi_i\int|T^{\kappa_i}f|^2\,d\kappa'_i$. Conditional Jensen gives $\|T^{\kappa_i}f\|^2_{L^2(\kappa'_i)}\le\int|f|^2\,dm$, and $\int T^{\kappa_i}f\,d\kappa'_i=\int f\,dm$. \end{proof} The atoms below $\Pfive$, forming the finite low part of the functional, have no quantitative mixing bound in (R4); in the lemma below they contribute only the factor $C'^{\gamma}$. The conditional operator of the low part has norm at most one, and, in the notation of the lemma, a frequency of total conductor above $H$ has conductor above $H/C'$ at the tail primes $p\ge\Pfive$. \begin{lemma}[Conductor decay with a finite prefix] \label{lem:record:prefix-conductor} Let $X'$ be a finite product of cyclic groups of prime-power order, and let $C'$ be a positive integer divisible by the reduced denominator of every character of $X'$. Let $\mathcal T$ be a finite set of primes not dividing $C'$. Let $\rho'$ be a probability measure on $X'^V$ with uniform one-slot marginals. Fix a slot $v\in V$ and $\gamma>0$, and for $p\in\mathcal T$ let $\rho_p$ be a probability measure on $\Fp^V$ with uniform one-slot marginals that is $(\gamma,v)$-mixing at this same slot $v$ (\cref{def:mixing}). Put $\rho=\rho'\otimes\bigotimes_{p\in\mathcal T}\rho_p$. Let $g_w\colon X'\times X_{\mathcal T}\to\C$ $(w\in V)$ and $H\ge1$, and suppose that $\widehat{g_v}(\xi)=0$ whenever $q(\xi)\le H$. Then \[ \Big|\int\prod_{w\in V}g_w(z_w)\,d\rho(z)\Big| \le\Big(\frac{C'}{H}\Big)^{\gamma}\|g_v\|_2\prod_{w\ne v}\|g_w\|_{2(d-1)}, \] with norms for the uniform probability measure. If instead $\rho'=m\bar\rho'$ with $m\ge0$ and $\bar\rho'$ as above, the right-hand side is multiplied by $m$. \end{lemma} \begin{proof} \emph{The conditional operator.} Let $\lambda'$, $\lambda_p$ be the laws of $z'_{V\setminus\{v\}}$ under $\rho'$ and of $z_{p,V\setminus\{v\}}$ under $\rho_p$, and $T'$, $T_p$ the conditional operators of $\rho'$, $\rho_p$ from slot $v$ (\cref{def:mixing}). By conditional Jensen and the uniform marginal of $z'_v$, \begin{equation}\label{eq:pre:contraction} \|T'f\|_{L^2(\lambda')}^2=\E_{\rho'}\big|\E_{\rho'}[f(z'_v)\mid z'_{V\setminus\{v\}}]\big|^2 \le\E_{\rho'}|f(z'_v)|^2=\|f\|_{L^2(X')}^2 , \end{equation} so $\|T'\|\le1$; no mixing of $\rho'$ is used. Each $T_p$ fixes the constants and $\int T_pf\,d\lambda_p=\E_{x\in\Fp}f(x)$, as $z_{p,v}$ is uniform; so $T_p$ is sector-preserving, with $\|T_p^\circ\|\le p^{-\gamma}$ by mixing. The factors of $\rho$ are independent, so the conditional law of $z_v$ given $z_{V\setminus\{v\}}$ is the product of theirs, and the conditional operator of $\rho$ from slot $v$ is $T=T'\otimes\bigotimes_{p\in\mathcal T}T_p$, from the uniform space $X'\times X_{\mathcal T}$ to $L^2(\lambda)$, $\lambda=\lambda'\otimes\bigotimes_p\lambda_p$. \emph{The support condition.} Apply \cref{lem:sector} with the spectator $X'$, $T_0=T'$, and the coordinates $p\in\mathcal T$. A character of $X'\times X_{\mathcal T}$ is $\xi'+\xi_{\mathcal T}$, with $\xi'$ a character of $X'$ and $\xi_{\mathcal T}$ of exact tail support $U\subseteq\mathcal T$; it lies in $H_U$, and since $q(\xi')$ divides $C'$ and is coprime to $q(\xi_{\mathcal T})=q_U$, its conductor is $q(\xi')q_U\le C'q_U$. The component $g_{v,U}$ of $g_v$ in $H_U$ collects the Fourier terms of $g_v$ of tail support $U$; if it is nonzero, then $HH/C'$. By \cref{lem:sector}(e), \[ \|Tg_v\|^2_{L^2(\lambda)}\le\sum_{U:\,q_U>H/C'}q_U^{-2\gamma}\|g_{v,U}\|_2^2 \le\Big(\frac{C'}H\Big)^{2\gamma}\|g_v\|_2^2 . \] \emph{Conclusion.} Conditioning on $z_{V\setminus\{v\}}$, then applying Cauchy--Schwarz in $L^2(\lambda)$ and H\"older with $d-1$ factors, \[ \Big|\int\prod_wg_w(z_w)\,d\rho\Big|=\Big|\int(Tg_v)(y)\prod_{w\ne v}g_w(y_w)\,d\lambda(y)\Big| \le\|Tg_v\|_{L^2(\lambda)}\prod_{w\ne v}\Big(\E_\lambda|g_w(y_w)|^{2(d-1)}\Big)^{\frac1{2(d-1)}} , \] and the $\lambda$-law of $y_w$ is the $\rho$-law of $z_w$, uniform on $X'\times X_{\mathcal T}$. The factor $m$ follows by multilinearity. \end{proof} With $X'$ trivial and $C'=1$ this is the same estimate with no low part. The factor $C'^{\gamma}$ from the low part does not decay with $H$, and all decay comes from the tail primes; the lemma is useful only because $C'$ is bounded independently of the scale. \Cref{sec:scale-comparison} applies it with $X'$ the product of the groups of the atoms below $\Pfive$ that are present, $C'=Q_{\rm pre}$, and $\mathcal T$ the tail primes $p\ge\Pfive$; \ref{it:record:R3} and \ref{it:record:R4} supply its hypotheses, and no mixing is used below $\Pfive$. The cancellation needs the same decay with a pair of slots as the source, and a truncation of the pair supports. \begin{lemma}[Decay by exact pair support]\label{lem:tr:pairsupport} Let $\mathcal T$ be a finite set of primes, $(u,v)$ an ordered pair of distinct slots and $\gamma>0$. For $p\in\mathcal T$ let $\rho_p$ be a probability measure on $\Fp^V$ whose $(u,v)$-marginal is $\Unif(\Om)$ and which is $(\gamma,(u,v))$-mixing, and put $\rho=\bigotimes_p\rho_p$. For $U\subseteq\mathcal T$ let $E_U$ be the conditional expectation, under $\bigotimes_p\Unif(\Om)$, onto the pair coordinates at the primes of $U$, and $q_U=\prod_{p\in U}p$. Then for $T_0\ge1$, every pair function $\varphi$ on $\prod_p\Om$ and every function $W$ of the labels of the other slots, \[ \Big|\int\varphi(z_u,z_v)W(z_{V\setminus\{u,v\}})\,d\rho(z)\Big|^2 \le\|W\|_2^2\Big[T_0^{-2\gamma}\|\varphi\|_2^2 +\sum_{q_U\le T_0}q_U^{-2\gamma}\|E_U\varphi\|_2^2\Big], \] with $\|\varphi\|_2$ and $\|E_U\varphi\|_2$ in $L^2(\bigotimes_p\Unif(\Om))$ and $\|W\|_2$ in $L^2$ of the $\rho$-law $\lambda$ of the other slots. \end{lemma} \begin{proof} The factors of $\rho$ are independent, so the conditional operator of $\rho$ from the pair $(u,v)$ to the other slots is $T=\bigotimes_pT_p$, with $T_p$ that of $\rho_p$; each $T_p$ fixes the constants and integrates against $\lambda_p$ as against $\Unif(\Om)$, so it is sector-preserving, with $\|T_p^\circ\|\le p^{-\gamma}$. Conditioning on the other slots and Cauchy--Schwarz give $|\int\varphi W\,d\rho|\le\|T\varphi\|_{L^2(\lambda)}\|W\|_2$, and $\|T\varphi\|^2\le\sum_Uq_U^{-2\gamma}\|\varphi_U\|_2^2$ by \cref{lem:sector}(e), with a trivial spectator. The supports with $q_U>T_0$ contribute at most $T_0^{-2\gamma}\|\varphi\|^2$. For the others, $E_U$ is the orthogonal projection onto $\bigoplus_{S\subseteq U}H_S$, so $\varphi_U$ is the $U$-component of $E_U\varphi$ and $\|\varphi_U\|_2\le\|E_U\varphi\|_2$. \end{proof} \paragraph{Consequences and what to read next.} The slot array, its cuts and its six queries (\cref{def:slot-array,lem:slot-array}), reflection positivity (\cref{def:rp}), sorting sequences (\cref{def:sorting}) and the multilinear averages of \cref{sec:positivity}, in the definitions only; the large sieve in Gram form and Khintchine's inequality, both proved here. The reference laws, the comparison law and admissibility (\cref{hyp:record:reference,def:record:comparison-law,def:admissible}) are interfaces whose instances are proved in Part~V. \space % End sections/06_lifts_sectors % Begin sections/07_kernel_statement \section{Cancellation from square-difference-freeness: statement of the kernel estimate}\label{sec:kernel} \paragraph{What this section proves and how to read it.} Square-difference-freeness of $A$ produces cancellation in exactly one place of the analytic stage: a bound for a truncated Fourier pairing of two functions that live on single residue classes of a modulus $D$, on ordered intervals, with no difference a positive square. This section states that bound; elsewhere, in the rescaling of \cref{sec:scale-comparison}, only the fact that the property passes to progressions with square step is used. The bound is applied in the accepted-pair cancellation (\cref{lem:record:density-can}), and through it in the wrap of the signed index form (\cref{lem:record:wrap-expansion}). The proof, a quadratic circle-method argument, is in \cref{app:kernel20}. The statement carries symbolic exponents because the cutoff of the functional and the range of the kernel have to match: the cancellation applies the kernel at the cutoff $H=N^{1/40}$ with moduli up to $N^{1/20}$, and a kernel bound proved for a smaller cutoff does not apply to it. The proof is the same for every admissible choice of exponents, so it is given once. \begin{definition}[Kernel notation]\label{def:kernel-notation} For $\xi\in\Q/\Z$ let $q(\xi)$ be its reduced denominator, and let \[ g(\xi)=\frac1{\varphi(q(\xi))}\sum_{m\in(\Z/q(\xi)\Z)^\times}e\big(\xi m^2\big), \qquad g(0)=1, \] be the \emph{unit quadratic average} at $\xi$; thus $|g(\xi)|\le1$, and for squarefree odd $q(\xi)$ this is the product formula of \cref{lem:square-shift}(d). For $H\ge1$ and any positive integer $D$ put \[ \Xi_{H,D}=\{\xi\in\Q/\Z:\ q(\xi)\le H,\ q(\xi)\ \text{squarefree},\ (q(\xi),D)=1\}. \] When $D=8d$ with $d$ odd, strict square classes modulo $D$ are those of \cref{def:strict-square-class}; by the paragraph after that definition they are exactly the squares of units modulo $D$, so a strict square class is the square of a unit modulo every odd prime power dividing $D$. For an integer $N\ge1$ and a finitely supported $F\colon\Z\to\C$ write $\widehat F(\xi)=N^{-1}\sum_nF(n)e(-n\xi)$ and $\|F\|_{\ell^2}=(\sum_n|F(n)|^2)^{1/2}$. \end{definition} Three exponents enter the proof: the modulus satisfies $D\lesssim N^\kappa$, the cutoff is $H\asymp N^{\beta/2}$, and the major arcs of the circle method are the neighbourhoods (of the radius fixed in \cref{app:kernel20}) of the fractions with denominator at most $N^\eta$; the saving is $H^{-1/3}\asymp N^{-\beta/6}$. \begin{definition}[Kernel exponents]\label{def:kernel-conditions} A triple $(\beta,\kappa,\eta)$ of positive numbers is \emph{admissible for the kernel} if the following seven strict inequalities hold: \begin{align*} &\text{(E1)}\quad \kappa+\tfrac\beta2-\tfrac\eta2<-\tfrac\beta6, & &\text{(E2)}\quad \kappa+\beta-\eta<-\tfrac\beta6, & &\text{(E3)}\quad \eta+2\kappa+\tfrac{3\beta}2-1<-\tfrac\beta6,\\ &\text{(E4)}\quad 2\eta+2\kappa+\beta-\tfrac12<-\tfrac\beta6, & &\text{(K0)}\quad 3\eta<1, & &\text{(K1)}\quad \kappa+\tfrac\beta2<\eta,\\ &\text{(K2)}\quad 2\eta+\kappa+\tfrac\beta2<1 . \end{align*} \end{definition} Here (K0) makes the major arcs disjoint, (K1) puts every centre of the model kernel (\cref{lem:record:K20-centres}) on a major arc, and (K2) separates distinct centres; (E1)--(E4) say that the four error terms of the circle method (the actual kernel on the minor arcs, the model kernel on the minor arcs, and the model and the actual kernel on the major arcs) are smaller than the saving $N^{-\beta/6}$. \begin{proposition}[The actual-square kernel]\label{prop:record:kernel20} Let $(\beta,\kappa,\eta)$ be admissible for the kernel, and fix $C_D,C_H\ge1$. There are $C$ and $N_0$, depending only on $\beta$, $\kappa$, $\eta$, $C_D$ and $C_H$, with the following property. Let $N\ge N_0$, let $D=8d\le C_DN^\kappa$ with $d$ odd (not necessarily squarefree), and let $C_H^{-1}N^{\beta/2}\le H\le C_HN^{\beta/2}$. Let $F,J\colon\Z\to\C$ be supported in $[1,N]$, in residue classes $a$ and $b$ modulo $D$. Suppose that $xC_0\Lsc^{-a}\alpha^\theta$, a remainder $C\Lsc^{-\sigma}\alpha$ is at most $(C/C_0)\Lsc^{a-\sigma}\alpha^{1-\theta}Y$, uniformly in $\alpha$, and the induction closes at the density exponent $\theta=1$ under the single condition $a<\sigma$. An absolute remainder $C\Lsc^{-\sigma}$ would be small compared with $Y$ only if $\alpha$ were not too small, which forces a sparseness condition and $\theta<1$ (\cref{rem:record:theta-ladder}). Second, the averaging is done in a fixed order. A sharp operator bound is applied at fixed shared labels, with a constant that does not depend on them; the Cauchy--Schwarz inequality is then integrated over the law of the shared labels; and only then is the comparison applied, to the two resulting unconditional energies (\cref{lem:record:folded-energy}). No comparison is pointwise in the selected labels, and no conditional distribution of the non-shared labels of one half, given the shared labels, is assumed to be uniform. The induction hypothesis is used only through the rescaling of \cref{lem:record:fibre-scale}. Fixing the labels at a set of atoms fixes a residue class; splitting the class into progressions with a square step returns the same problem at a shorter scale, because a square-difference-free set meets a progression of square step in a rescaled square-difference-free set. \subsection{Numerical exponents and the inequalities they must satisfy}\label{subsec:scale:stage} The exponents of the analytic estimates are fixed once. \begin{definition}[Analytic stage]\label{def:record:analytic-stage} $\beta=1/20$ is the exponent of the functional; $\eta=17/100$ is the major-arc exponent of \cref{app:kernel20}; $\gamma=255/1024$ is the one-slot and pair mixing exponent at the tail primes $p\ge\Pfive$; selected sets of field primes have product at most $N^\tau$, $\tau=1/201$; $T_0=N^{t_{\rm an}}$, $t_{\rm an}=1/60$, is the truncation of pair supports in the cancellation; $H=N^{\beta/2}=N^{1/40}$ is the outside cutoff of the comparison and of the kernel; $\sigma=1/825$ is the error exponent; $\delta=10^{-10}$ is the moment loss per slot and $\ell_0=10^{-8}$ the moment loss of the large-product estimate. A \emph{constant} depends only on these parameters, on $\Kint$, $\Mzero$, $Q_{\rm pre}$, the reference laws and the moment constants of \cref{lem:record:lift-moments}; it never depends on $\Lsc$, $A$, the selected atoms, their labels, the intervals or the residues. \end{definition} \paragraph{The stage inequalities.} \Cref{cert:record:analytic-stage} (\cref{app:certificates}) checks in exact rational arithmetic that these parameters satisfy the following strict inequalities: \begin{enumerate}[label=(S\arabic*)] \item $\gamma\beta/2-\tau-72\delta-\sigma>0$; \item $\gamma t_{\rm an}-72\delta-\sigma>0$; \item $\beta/6-t_{\rm an}(1/2-\gamma)-72\delta-\sigma>0$; \item $\tau/4-\ell_0-\sigma>0$; \item $1-2\tau-6\beta>0$, $\beta/2-\tau>0$, $\beta/2-t_{\rm an}>0$ and $\beta(1-2\tau)-\beta/2>0$; \item the seven kernel slacks of \cref{lem:record:arcs}, computed in \cref{cor:kernel20}, are positive; \item the tail coefficients and the tail gates of \cref{lem:record:tail-mixing} hold; only the gate at $\Pfive$ is used. \end{enumerate} Here (S1) is used in the comparison, where only the weaker $\gamma\beta/2-72\delta>\sigma$ is needed for an individual averaged estimate (\cref{lem:record:density-dc}); its full slack also absorbs the sum of raw comparison errors in \cref{prop:density:production}. Conditions (S2) and (S3) are used in the accepted-pair cancellation (\cref{lem:record:density-can}), where they are the two saving exponents $\gamma t_{\rm an}=17/4096$ and $1/120-t_{\rm an}(1/2-\gamma)=17/4096$ less the moment loss; (S4) in the large-product estimate (\cref{lem:record:density-lp}); the four inequalities of (S5), in this order, give the moment hypothesis at the target scale, complete selected fibres ($HD_E\le Q$ when $q_E\le N^\tau$), complete pair fibres and the kernel modulus ($HN^{t_{\rm an}}Q_{\rm pre}\le Q$), and the target cutoff ($n^\beta\ge H$), through \cref{lem:scale-conditions}; (S6) is the admissibility of the kernel triple of \cref{cor:kernel20}, used in \cref{app:kernel20}, and (S7) is used in \cref{lem:record:tail-mixing}. None of (S1)--(S7) involves $\Kint$ or the clique prefix. Apart from the slot prices $\xi_v$ and the density factors $\kappa_v$ of \cref{def:record:structured-energy}, in which $\Kint$, divisors of $\Mzero$ and the clique powers $p^{e_p}$ appear explicitly, the fixed integers $\Kint$, $\Mzero$, $Q_{\rm cl}$ and $Q_{\rm pre}$ enter the estimates of this section only through constants, through the term $u_\Lsc\to0$ and through the starting scale of \cref{lem:scale-conditions}; this is possible because every inequality is strict. \subsection{Residue-class restriction and square-step rescaling}\label{subsec:scale:fibres} For a set $E$ of atoms of $\mathcal A_N$ we write $X_E$ for the product of their groups, $D_E=|X_E|$ for its full order, $q_E$ for the product of the primes of the atoms of $E$ with $e_p=1$, and $E_{\rm cl}=E\cap\mathcal P_1$ for its clique primes. Thus $D_E=q_E\prod_{p\in E_{\rm cl}}p^{e_p}\le q_EQ_{\rm cl}$. For a divisor $D_0$ of $\Mzero$ put $D=D_0D_E$. The two factors are coprime: the primes of $\Mzero$ are $2$ and the primes $p\equiv3\pmod4$ below $Q_3$, none of which is a prime of an atom. The \emph{square step} of $E$ and $D_0$ is the least perfect square divisible by $D$ \eqref{eq:sq}, \begin{equation}\label{eq:square-step} R=\sq(D)=\sq(D_0)\,q_E^2\prod_{p\in E_{\rm cl}}p^{e_p}; \end{equation} the second form holds because $\sq$ is multiplicative on coprime factors, $q_E$ is squarefree and every $e_p$ is even. The primes of $R$ are those of $D$, so $R$ is coprime to every prime of an atom outside $E$. \begin{lemma}[Exact fibres and the square-step comparison input] \label{lem:record:fibre-scale} Let $\Lsc\ge2$, $N=\Kint\Lsc$, let $A\subseteq[N]$ be square-difference-free and let $E\subseteq\mathcal A_N$, with $\mathcal S=\mathcal A_N\setminus E$. Let $I\in\mathcal I_\Lsc$, $D_0\mid\Mzero$, $s\in\Z/D_0\Z$, $z\in X_E$ and $g=g^{I,D_0,s}$. Put $D=D_0D_E$, let $\mathfrak a\bmod D$ be the class with $\mathfrak a\equiv s\pmod{D_0}$ and $\mathfrak a\equiv z_p\pmod{p^{e_p}}$ for the primes $p$ of $E$, and let \[ \alpha_{\rm f}=\frac D{|I|}\,\#\{x\in A\cap I:\ x\equiv\mathfrak a\ (\mathrm{mod}\ D)\} \] be the density of $A$ in the fibre of $z$. \begin{enumerate}[label=(\alph*)] \item \emph{(Exact fibre.)} For every $f:I\to\C$ and every character $\xi$ of $X_{\mathcal S}$ with $q(\xi)D_E\le Q$, the coefficient at $\xi$ of the specialization $(\mathcal L_{I,N}f)(z,\cdot)$ is $(D_E/|I|)\sum_{x\in I,\,x\equiv z\,(D_E)}f(x)e(-x\xi)$, where $x\equiv z\ (D_E)$ means $x\equiv z_p\pmod{p^{e_p}}$ for each prime $p$ of $E$. In particular \[ \widehat{g(z,\cdot)}(\xi)=\frac D{|I|}\sum_{\substack{x\in A\cap I\\ x\equiv\mathfrak a\,(D)}}e(-x\xi). \] \item \emph{(Square step.)} Let $R=\sq(D)$ be the square step of $E$ and $D_0$, $\ell=\lceil|I|/(\Kint R)\rceil$, $n=\Kint\ell$ and $\lambda=Rn/|I|$. Write $I=c_I+[|I|]$, $A_I=(A\cap I)-c_I\subseteq[|I|]$ and $J_{\mathfrak a}=\{j\in[R]:j\equiv\mathfrak a-c_I\pmod D\}$ (so $|J_{\mathfrak a}|=R/D$), and for $j\in J_{\mathfrak a}$ put $c_j=j-R$, \[ A'_j=\{n'\in[n]:\ Rn'+c_j\in A_I\},\qquad T_j(y)=R^{-1}(y-c_I-c_j)\quad(y\in X_{\mathcal S}), \] $h_j=\mathcal L^{\mathcal S}_{[n],n^\beta}\one_{A'_j}$, the lift of $\one_{A'_j}$ on $X_{\mathcal S}$ with cutoff $n^\beta$, and \[ \widetilde g=\frac{\lambda D}{R}\sum_{j\in J_{\mathfrak a}}h_j\circ T_j , \] the \emph{square-step model} of $g(z,\cdot)$. Each $A'_j$ is square-difference-free, each $T_j$ is a map of the form in \ref{it:record:R3}, and \[ \frac DR\sum_{j\in J_{\mathfrak a}}\alpha_j=\frac{\alpha_{\rm f}}\lambda,\qquad \alpha_j=\frac{|A'_j|}n . \] If $H\le n^\beta$ and $HD_E\le Q$, then $\widetilde g$ and $g(z,\cdot)$ have the same Fourier coefficient at every character $\xi$ of $X_{\mathcal S}$ with $q(\xi)\le H$. \item \emph{(Restoration.)} $Z_{\mathcal S}(h_j)\le\Yf(\ell,A'_j)$ for every $j\in J_{\mathfrak a}$. \item \emph{(Scales.)} $1\le\lambda<1+\Kint R/|I|$ and $\ell\ge\Lsc/\xi_I$ with $\xi_I=(N/|I|)R$. Moreover $\ell<\Lsc$, unless $E=\emptyset$, $D_0=1$ and $I=[N]$. \item \emph{(Moments.)} If $n\ge10n^{6\beta}$, then for every integer $r\ge1$ and every $\epsilon>0$, $\|\widetilde g\|_{2r}^{2r}\le C_{r,\epsilon}N^\epsilon\lambda^{2r-1}\alpha_{\rm f}$, with the constant $C_{r,\epsilon}$ of \cref{lem:record:lift-moments}(c). \end{enumerate} \end{lemma} \begin{proof} (a) Every prime of $D_0$ divides $\Mzero$ and none divides $D_E$, so the class $\mathfrak a$ exists and is unique. Write a character of $G_N$ as $\xi+\zeta$ with $\xi$ a character of $X_{\mathcal S}$ and $\zeta$ one of $X_E$; their conductors are coprime, so $q(\xi+\zeta)=q(\xi)q(\zeta)$, and $q(\zeta)$ divides $D_E$. If $q(\xi)D_E\le Q$, every character $\zeta$ of $X_E$ occurs together with $\xi$ in the lift, so the coefficient of $e(y\cdot\xi)$ in $(\mathcal L_{I,N}f)(z,\cdot)$ is \[ \frac1{|I|}\sum_{x\in I}f(x)e(-x\xi)\sum_{\zeta}e((z-x)\cdot\zeta) =\frac{D_E}{|I|}\sum_{\substack{x\in I\\ x\equiv z\,(D_E)}}f(x)e(-x\xi), \] by orthogonality of the characters of each cyclic group $\Z/p^{e_p}\Z$. For $f=D_0\one_{x\equiv s\,(D_0)}\one_A$ the Chinese remainder theorem gives the second formula, and it holds also when the fibre is empty. Completeness of the selected group is necessary here: for the cyclic group $\Z/9\Z$ with cutoff $3$, $I=[1,9]$, $A=\{9\}$ and label $3$, the retained characters have numerators $0,3,6$ and the specialized lift equals $1/3$, although the fibre $\{x\equiv3\ (9)\}\cap A$ is empty. (b) Since $D$ divides $R$, exactly $R/D$ residues $j\in[R]$ satisfy $j\equiv\mathfrak a-c_I\pmod D$. The map $(n',j)\mapsto Rn'+c_j=R(n'-1)+j$ is a bijection $[n]\times[R]\to[Rn]$, and $[|I|]\subseteq[Rn]$ because $Rn\ge|I|$; restricted to $j\in J_{\mathfrak a}$ it is a bijection onto the integers of $[Rn]$ in the class $\mathfrak a-c_I\bmod D$. The integers of $(|I|,Rn]$ do not lie in $A_I$, so the padding contributes nothing, and $\sum_{j\in J_{\mathfrak a}}|A'_j|=\#\{x\in A\cap I:x\equiv\mathfrak a\ (D)\}$. Therefore $(D/R)\sum_j\alpha_j=D\,\#\{x\in A\cap I:x\equiv\mathfrak a\ (D)\}/(Rn) =\alpha_{\rm f}|I|/(Rn)=\alpha_{\rm f}/\lambda$. If $n'_11$, then $R\ge4$, because $R$ is a perfect square, and $\ell\le\lceil N/(4\Kint)\rceil=\lceil\Lsc/4\rceil<\Lsc$. If $D=1$, then $E=\emptyset$, $D_0=1$ and $R=1$; for $I=I_b$, $\ell=\lceil\Lsc/\Kint\rceil<\Lsc$, since $\Kint\ge2$ and $\Lsc\ge2$. (e) $T_j$ preserves the uniform measure, so by Minkowski $\|\widetilde g\|_{2r}\le\lambda\frac DR\sum_j\|h_j\|_{2r}$. Each $h_j$ is a whole-support piece of the lift of $\one_{A'_j}$ on $X_{\mathcal S}$ with cutoff $n^\beta$, and $|[n]|\ge10(n^\beta)^6$, so $\|h_j\|_{2r}^{2r}\le C_{r,\epsilon}N^\epsilon\alpha_j$ by \cref{lem:record:lift-moments}(c) and $n\le N$. Concavity of $x\mapsto x^{1/(2r)}$ and (b) give $\|\widetilde g\|_{2r}\le\lambda(C_{r,\epsilon}N^\epsilon\alpha_{\rm f}/\lambda)^{1/(2r)}$. \end{proof} The hypotheses of (b) and (e) hold for every selection used below, from a fixed starting scale on. We collect once all the conditions on the scale that the comparison and the cancellation need. \begin{lemma}[Scale conditions]\label{lem:scale-conditions} There is $\Lsc_*\ge2$, depending only on the analytic stage, $\Kint$, $\Mzero$, $Q_{\rm cl}$ and $Q_{\rm pre}$, such that for every $\Lsc\ge\Lsc_*$, with $N=\Kint\Lsc$, $Q=N^\beta$, $H=N^{\beta/2}$ and $T_0=N^{t_{\rm an}}$: \begin{enumerate}[label=(\roman*)] \item $\Lsc\ge10N^{6\beta}$; \item $HQ_{\rm cl}N^\tau\le Q$; \item $n_0:=N^{1-2\tau}/(\Kint\Mzero^2Q_{\rm cl})$ satisfies $n_0^\beta\ge H$ and $n_0\ge10N^{6\beta}$; \item $\Kint^2\Mzero^2Q_{\rm cl}N^{2\tau-1}\le1$; \item $N^\beta\ge\Pfive$, so that every prime of $[\Pfour,\Pfive)$ is a coordinate of $G_N$; \item $HQ_{\rm pre}T_0\le Q$ and $\Mzero Q_{\rm pre}T_0\le\min(N^{1/20},\Lsc)$; \item $N$ is at least the thresholds $N_0$ and $N_0'$ of \cref{prop:record:kernel20}(i)--(iii) at the triple of \cref{cor:kernel20}, $(\beta,\kappa,\eta)=(1/20,1/20,17/100)$, with $C_D=C_H=1$, $\mathcal P_0=\mathcal P_1$ and $m_p=e_p/2$. \end{enumerate} Consequently, let $E\subseteq\mathcal A_N$ with $q_E\le N^\tau$, $D_0\mid\Mzero$ and $I\in\mathcal I_\Lsc$, and let $R$, $n$ and $\lambda$ be as in \cref{lem:record:fibre-scale}(b). Then $R\le\Mzero^2Q_{\rm cl}N^{2\tau}$, $HD_E\le Q$, $n_0\le n\le N$, $n^\beta\ge H$ and $n\ge10n^{6\beta}$; and $1\le\lambda\le2$ and $\lambda^{72}\le1+u_\Lsc$, where \[ u_\Lsc=\big(1+\Kint^2\Mzero^2Q_{\rm cl}N^{2\tau-1}\big)^{72}-1 \] tends to zero as $\Lsc\to\infty$. In particular the hypotheses of \cref{lem:record:fibre-scale}(b) and (e) hold. \end{lemma} \begin{proof} Each of (i)--(iv) and (vi) compares two powers of $N$, up to fixed constants, with a positive gap in the exponents: $1-6\beta>0$ for (i), $\beta/2-\tau>0$ for (ii), $\beta(1-2\tau)-\beta/2>0$ and $1-2\tau-6\beta>0$ for (iii), $1-2\tau>0$ for (iv), and $\beta/2-t_{\rm an}>0$, hence also $\beta-t_{\rm an}>0$ and $1-t_{\rm an}>0$, for (vi); all of them follow from (S5). Conditions (v) and (vii) are fixed thresholds. So all seven hold for large $\Lsc$. For the consequences, $\sq(D_0)\le D_0^2\le\Mzero^2$ and $\prod_{p\in E_{\rm cl}}p^{e_p}\le Q_{\rm cl}$ give $R\le\Mzero^2Q_{\rm cl}N^{2\tau}$, and $D_E\le q_EQ_{\rm cl}$ with (ii) gives $HD_E\le Q$. Next $n=\Kint\lceil|I|/(\Kint R)\rceil\le\Kint\lceil N/\Kint\rceil=N$, and $n\ge|I|/R\ge(N/\Kint)/(\Mzero^2Q_{\rm cl}N^{2\tau})=n_0$ because $|I|\ge\Lsc=N/\Kint$; by (iii), $n^\beta\ge n_0^\beta\ge H$ and $n\ge n_0\ge10N^{6\beta}\ge10n^{6\beta}$. Finally \cref{lem:record:fibre-scale}(d) gives $1\le\lambda<1+\Kint R/|I|\le1+\Kint^2\Mzero^2Q_{\rm cl}N^{2\tau-1}$, which is at most $2$ by (iv), and raising to the power $72$ gives $\lambda^{72}\le1+u_\Lsc$. \end{proof} Conditions (i)--(iv) are used in the comparison (\cref{lem:record:density-dc,prop:record:density-structured}), (i) and (v)--(vii) in the cancellation (\cref{lem:record:density-can}), and (i) in the large-product estimate (\cref{lem:record:density-lp}). \subsection{Pinned averages at a least counterexample} \label{subsec:scale:structured} All energy estimates are made at a least counterexample to the bound that the induction proves. \begin{definition}[Least normalized counterexample] \label{def:record:counterexample} Let $a>0$, $0<\theta\le1$ and $C_0\ge1$. A pair $(\Lsc,A)$, with $A\subseteq[\Kint\Lsc]$ square-difference-free, is a \emph{least normalized counterexample} for $(a,\theta,C_0)$ if $\Yf(\Lsc,A)>C_0\Lsc^{-a}\alpha^\theta$, and $\Yf(\ell,A')\le C_0\ell^{-a}\alpha_{A'}^\theta$ for every $\ell<\Lsc$ and every square-difference-free $A'\subseteq[\Kint\ell]$, where $\alpha_{A'}=|A'|/(\Kint\ell)$ and $0^\theta=0$. Then $\alpha>0$, since $F_\emptyset=0$. \end{definition} \begin{definition}[Structured energies and prices] \label{def:record:structured-energy} Let $a>0$ and $0<\theta\le1$ be the exponents of the induction. Let $\Lsc\ge1$, $N=\Kint\Lsc$, let $A\subseteq[N]$ be square-difference-free and $\alpha=|A|/N>0$. A \emph{structured energy} at $(\Lsc,A)$ is given by the following data. \begin{enumerate}[label=(\alph*)] \item A set $E\subseteq\mathcal A_N$ of \emph{selected} atoms with $q_E\le N^\tau$; put $\mathcal S=\mathcal A_N\setminus E$. \item A finite signed measure $\rho$ on $X_E^V$ whose variation $|\rho|$ has every one-slot marginal equal to $\|\rho\|\Unif(X_E)$, where $\|\rho\|=|\rho|(X_E^V)$. \item For each $v\in V$ a divisor $D_{0,v}$ of $\Mzero$ and a length $M_v\in\{\Lsc,N\}$, and a probability law $\mathbf P$ on index vectors $\omega=(I_v,s_v)_{v\in V}$ with $I_v\in\mathcal I_\Lsc$, $|I_v|=M_v$ and $s_v\in\Z/D_{0,v}\Z$. \end{enumerate} The energy is \[ \mathfrak E=\E_{\omega\sim\mathbf P}\int\Lambda_{\mu_{\mathcal S}} \big((g_v^\omega(z_v,\cdot))_{v\in V}\big)\,d\rho(z),\qquad g_v^\omega=g^{I_v,D_{0,v},s_v}. \] A slot is \emph{unchanged} if $E=\emptyset$, $D_{0,v}=1$ and $M_v=N$ (then $g_v^\omega=F_A$), and \emph{changed} otherwise. With $R_E=q_E^2\prod_{p\in E_{\rm cl}}p^{e_p}$, the slot prices are \[ \xi_v=\frac N{M_v}\,\sq(D_{0,v})R_E,\qquad \bar\alpha_v=\E_{\mathbf P}\,\frac{D_{0,v}}{M_v}\#\{x\in A\cap I_v: x\equiv s_v\ (D_{0,v})\}. \] The \emph{main price} is $\Pi_{\rm main}=\prod_v\xi_v^{a/72}\prod_{v\ \rm changed}(\bar\alpha_v/\alpha)^{\theta/72}$. If $\kappa_v\ge1$ are numbers with $\bar\alpha_v\le\kappa_v\alpha$ for every changed slot, the \emph{coarse price} is $\Pi=\prod_v\xi_v^{a/72}\prod_{v\ \rm changed}\kappa_v^{\theta/72}$; thus $\Pi\ge\max(1,\Pi_{\rm main})$. \end{definition} One may take $\kappa_v=1$ if $(I_v,s_v)$ is uniform on $\{I_1,\dots,I_\Kint\}\times\Z/D_{0,v}\Z$, or if $M_v=N$ and $s_v$ is uniform; $\kappa_v=\Kint$ if $s_v$ is uniform given a fixed interval $I_v$, since then $\bar\alpha_v=\alpha_{I_v}\le\Kint\alpha$; and always $\kappa_v=\Mzero\Kint$. Since $\sq(D_{0,v})R_E=\sq(D_{0,v}D_E)$, the price $\xi_v$ is $\xi_{I_v}$ of \cref{lem:record:fibre-scale}(d): for $M_v=N$ it is the square step of $E$ and $D_{0,v}$, and for $M_v=\Lsc$ it is $\Kint$ times it. If a clique prime $p$ belongs to $E$, its contribution to $\prod_v\xi_v^{a/72}$ over the $72$ slots is $p^{e_pa}$; a prefix atom not in $E$ contributes no factor. \begin{lemma}[Averaged comparison with a density factor] \label{lem:record:density-dc} There is a constant $C_{\rm dc}$ with the following property. Let $\Lsc\ge\Lsc_*$ (\cref{lem:scale-conditions}) and consider a structured energy at $(\Lsc,A)$. Put $H=N^{1/40}$. For every $\omega$, $z\in X_E^V$ and changed slot $v$, let $\widetilde g_v^\omega(z_v,\cdot)$ be the square-step model of \cref{lem:record:fibre-scale}(b) for $(E,I_v,D_{0,v},s_v,z_v)$; for an unchanged slot put $\widetilde g_v^\omega=F_A$. Let $\widetilde{\mathfrak E}$ be the energy with $\widetilde g_v^\omega$ in place of $g_v^\omega$. Then \begin{multline*} \E_{\mathbf P}\int\big|\Lambda_{\mu_{\mathcal S}}((g_v^\omega(z_v,\cdot))_v) -\Lambda_{\mu_{\mathcal S}}((\widetilde g_v^\omega(z_v,\cdot))_v)\big|\,d|\rho|(z)\\ \le C_{\rm dc}\|\rho\|N^{-\gamma\beta/2+72\delta}\alpha \le C_{\rm dc}\|\rho\|\Lsc^{-\sigma}\alpha ; \end{multline*} in particular $|\mathfrak E-\widetilde{\mathfrak E}|\le C_{\rm dc}\|\rho\|\Lsc^{-\sigma}\alpha$. \end{lemma} \begin{proof} \emph{Step 0: the scale.} By \cref{lem:scale-conditions}, applied to $E$ and each $D_{0,v}$, $I_v$, the hypotheses $H\le n^\beta$, $HD_E\le Q$ and $n\ge10n^{6\beta}$ of \cref{lem:record:fibre-scale}(b),(e) hold at every changed slot, and $1\le\lambda_v\le2$. \emph{Step 1: telescoping.} Fix $\omega$ and $z$, and let $v_1,\dots,v_k$ be the changed slots. Then $\Lambda((g_v)_v)-\Lambda((\widetilde g_v)_v)=\sum_{i=1}^k\Lambda(Y^{(i)})$, where $Y^{(i)}$ carries $\widetilde g_{v_j}$ at $v_j$ for $ji$, and $F_A$ at the unchanged slots (all specialized at $z$). By \cref{lem:record:fibre-scale}(b), the input at $v_i$ has no character of conductor at most $H$. The law $\mu_{\mathcal S}$ is the product of the laws of the atoms of $\mathcal S$ below $\Pfive$, a probability measure with uniform one-slot marginals by \ref{it:record:R3}, and of the tail laws $\mu_p$, $p\ge\Pfive$, which satisfy the mixing hypothesis \ref{it:record:R4} at every slot (in the notation of \cref{def:mixing}). Every character of the first factor has conductor dividing $Q_{\rm pre}$. By \cref{lem:record:prefix-conductor} with $C'=Q_{\rm pre}$, \[ |\Lambda(Y^{(i)})|\le\Big(\frac{Q_{\rm pre}}H\Big)^{\gamma} \big\|(g_{v_i}-\widetilde g_{v_i})(z_{v_i},\cdot)\big\|_2 \prod_{w\ne v_i}\|Y^{(i)}_w(z_w,\cdot)\|_{142}. \] \emph{Step 2: averaging.} Integrate over $\omega\sim\mathbf P$ and $z\sim|\rho|/\|\rho\|$ and apply H\"older's inequality with the exponents $2$ and $142$ ($71$ times), so that $1/2+71/142=1$: \[ \E\Big[\|X\|_2\prod_{w}\|Y_w\|_{142}\Big]\le(\E\|X\|_2^2)^{1/2} \prod_w(\E\|Y_w\|_{142}^{142})^{1/142}. \] Under $|\rho|/\|\rho\|$ each $z_w$ is uniform on $X_E$ and independent of $\omega$. Hence, by Fubini and \cref{lem:record:lift-moments}(c) (the lift on $G_N$ is a whole-support piece of the kind treated there, with $\mathcal S'=\mathcal P_1$, and $|I_w|\ge\Lsc\ge10N^{6\beta}$), for $2r\in\{2,142\}$ and every $\epsilon>0$, \[ \E\|g_w^\omega(z_w,\cdot)\|_{2r}^{2r}=\E_\omega\|g_w^\omega\|_{L^{2r}(G_N)}^{2r} \le C_{r,\epsilon}N^\epsilon\Mzero^{2r}\,\E_\omega\alpha_{I_w} \le C_{r,\epsilon}N^\epsilon\Mzero^{2r}\Kint\alpha , \] because $\alpha_I\le\Kint\alpha$ for $|I|\ge N/\Kint$; the same holds for $F_A$. By \cref{lem:record:fibre-scale}(e), with $\lambda_w\le2$, $\E\|\widetilde g_w(z_w,\cdot)\|_{2r}^{2r}\le C_{r,\epsilon}N^\epsilon2^{2r-1} \E\alpha_{{\rm f},w}$, where $\alpha_{{\rm f},w}$ is the fibre density of $z_w$, and $\E_z\alpha_{{\rm f},w}=D_{0,w}\#\{x\in A\cap I_w:x\equiv s_w\}/|I_w| \le\Mzero\Kint\alpha$, because the class $\mathfrak a(z_w)$ is uniform among the $D_E$ classes modulo $D$ compatible with $s_w$. Finally $\|X\|_2^2\le2\|g\|_2^2+2\|\widetilde g\|_2^2$. Thus every factor is at most $(C_\epsilon N^\epsilon\alpha)^{1/(2r)}$, and each of the at most $72$ terms is bounded by $Q_{\rm pre}^\gamma H^{-\gamma}C_\epsilon N^{\epsilon}\alpha$, the density exponents adding to $1/2+71/142=1$. Take $\epsilon=72\delta$. Finally $N^{-\gamma\beta/2+72\delta}\le N^{-\sigma}\le\Lsc^{-\sigma}$ by (S1). \end{proof} \begin{proposition}[Density-structured energy estimate] \label{prop:record:density-structured} Let $0<\theta\le1$, $a>0$ and $C_0\ge1$, and let $(\Lsc,A)$ be a least normalized counterexample for $(a,\theta,C_0)$ (\cref{def:record:counterexample}), with $\Lsc\ge\Lsc_*$ and $Y=\Yf(\Lsc,A)$. Then every structured energy at $(\Lsc,A)$ satisfies \[ |\mathfrak E|\le\|\rho\|\big[(1+u_\Lsc)\,\Pi_{\rm main}\,Y +C_{\rm dc}\Lsc^{-\sigma}\alpha\big] \le\|\rho\|\Big(1+u_\Lsc+\frac{C_{\rm dc}}{C_0}\Lsc^{a-\sigma} \alpha^{1-\theta}\Big)\Pi\,Y, \] with $u_\Lsc\to0$ as in \cref{lem:scale-conditions}. \end{proposition} \begin{proof} By \cref{lem:record:density-dc} it suffices to bound $\widetilde{\mathfrak E}$ by $\|\rho\|(1+u_\Lsc)\Pi_{\rm main}Y$. Fix $\omega$ and $z$. By the signed H\"older inequality of \cref{lem:record:holder}(a) for $\mu_{\mathcal S}$, $|\Lambda_{\mu_{\mathcal S}}((\widetilde g_v)_v)|\le \prod_vZ_{\mathcal S}(\widetilde g_v(z_v,\cdot))^{1/72}$. At an unchanged slot $E=\emptyset$, $\mathcal S=\mathcal A_N$ and $Z_{\mathcal S}(F_A)=Y$. At a changed slot $v$, with the data $D,R,J_{\mathfrak a},h_j,A'_j,\lambda_v,\ell_v$ of \cref{lem:record:fibre-scale}(b) for that slot, the triangle inequality for the seminorm $Z_{\mathcal S}^{1/72}$ and its invariance under the maps $T_j$ (\cref{lem:record:holder}(a),(c)), then \cref{lem:record:fibre-scale}(c), give \[ Z_{\mathcal S}(\widetilde g_v)^{1/72}\le\lambda_v\frac DR\sum_{j\in J_{\mathfrak a}} Z_{\mathcal S}(h_j)^{1/72}\le\lambda_v\frac DR\sum_{j\in J_{\mathfrak a}} \Yf(\ell_v,A'_j)^{1/72}. \] Here $\ell_v<\Lsc$ by \cref{lem:record:fibre-scale}(d), so the hypothesis on smaller scales gives $\Yf(\ell_v,A'_j)\le C_0\ell_v^{-a}\alpha_j^\theta$, also when $A'_j=\emptyset$. Concavity of $x\mapsto x^{\theta/72}$ and \cref{lem:record:fibre-scale}(b) give $\frac DR\sum_j\alpha_j^{\theta/72}\le(\alpha_{{\rm f},v}/\lambda_v)^{\theta/72}$, where $\alpha_{{\rm f},v}$ is the fibre density of $z_v$, hence \[ Z_{\mathcal S}(\widetilde g_v)\le\lambda_v^{72-\theta}C_0\ell_v^{-a}\alpha_{{\rm f},v}^\theta \le(1+u_\Lsc)C_0\Lsc^{-a}\xi_v^a\alpha_{{\rm f},v}^\theta , \] using $\ell_v\ge\Lsc/\xi_v$ and $\lambda_v^{72}\le1+u_\Lsc$ (\cref{lem:record:fibre-scale}(d), \cref{lem:scale-conditions}). The price $\xi_v$ does not depend on $\omega$ or $z$. Every factor is nonnegative, so H\"older's inequality with $72$ equal exponents on the probability space of $(\omega,z)$, with law $\mathbf P\otimes|\rho|/\|\rho\|$, gives \[ |\widetilde{\mathfrak E}|\le\|\rho\|\prod_v\big(\E\,Z_{\mathcal S} (\widetilde g_v(z_v,\cdot))\big)^{1/72}. \] At a changed slot, Jensen's inequality ($\theta\le1$) and $\E\alpha_{{\rm f},v}=\bar\alpha_v$ (as in Step~2 of \cref{lem:record:density-dc}) give $\E Z_{\mathcal S}(\widetilde g_v)\le (1+u_\Lsc)C_0\Lsc^{-a}\alpha^\theta\xi_v^a(\bar\alpha_v/\alpha)^\theta\le (1+u_\Lsc)Y\xi_v^a(\bar\alpha_v/\alpha)^\theta$, since $C_0\Lsc^{-a}\alpha^\thetaH},\qquad \Psi_{\le H}=\sum_{q(\xi)\le H}\widehat{g_1}(-\xi)\widehat{g_2}(\xi)g(\xi), \] the sums running over the characters of $X_{\mathcal S'}$, with $g(\xi)$ the unit quadratic average (\cref{def:kernel-notation}). Since every prime of $\mathcal S'$ exceeds $64$, $|g(\xi)|\le q(\xi)^{-1/3}H$, and Cauchy--Schwarz and Parseval give $|\Psi_{>H}|\le H^{-1/3}\|g_1\|_2\|g_2\|_2$. For the low part put $D=\Mzero D_{\rm pre}q_U$. By \cref{lem:scale-conditions}(vi), $HD_{\rm pre}q_U\le Q$, so \cref{lem:record:fibre-scale}(a), with the conditioned atoms in the role of $E$, gives for $q(\xi)\le H$ \[ \widehat{g_1}(\xi)=\frac D\Lsc\sum_{\substack{n\in A\cap I_b\\ n\equiv\mathfrak a_1\,(D)}}e(-n\xi), \qquad \widehat{g_2}(\xi)=\frac D\Lsc\sum_{\substack{n\in A\cap I_{b+1}\\ n\equiv\mathfrak a_2\,(D)}}e(-n\xi), \] where $\mathfrak a_1\equiv s$, $\mathfrak a_2\equiv s+r\pmod\Mzero$, $\mathfrak a_1\equiv x_u$, $\mathfrak a_2\equiv x_v$ on $X_{\rm pre}$ and $\mathfrak a_1\equiv y_u$, $\mathfrak a_2\equiv y_v$ on $X_U$. Every prime below $\Pfive$ and every prime of $U$ divides $D$; hence the characters of $X_{\mathcal S'}$ with $q(\xi)\le H$ are exactly the elements of $\Xi_{H,D}$ (\cref{def:kernel-notation}), since a squarefree $q\le H\le N^\beta$ coprime to $D$ has all its primes in $\mathcal S'$. The difference $\mathfrak a_2-\mathfrak a_1$ is $r$ modulo $\Mzero$, a nonzero square at the primes of $U$ and at the primes below $\Pfive$ with $e_p=1$, and at the clique primes nonzero of even valuation below $e_p$ with square unit part, by (b). With $F_i=\one_A\one_{I_{b+i-1}}\one_{n\equiv\mathfrak a_i\,(D)}$ on $[N]$ and $\widehat F_i$ normalized by $N$, we have $\widehat{g_1}(-\xi)=(DN/\Lsc)\widehat F_1(-\xi)$ and $\widehat{g_2}(\xi)=(DN/\Lsc)\widehat F_2(\xi)$. The supports are ordered, since $I_b$ lies below $I_{b+1}$, and no difference is a positive square. So \cref{prop:record:kernel20}(iii) applies in the form of \cref{cor:kernel20}, with $D\le N^{1/20}$ (\cref{lem:scale-conditions}(vi)), $H=N^{1/40}$ and $N$ above the thresholds of the proposition (\cref{lem:scale-conditions}(vii)): \begin{align*} |\Psi_{\le H}|&=\frac{DN^2}{\Lsc^2}\Big|D\sum_{\xi\in\Xi_{H,D}}g(\xi) \widehat F_1(-\xi)\widehat F_2(\xi)\Big|\\ &\le\frac{DN^2}{\Lsc^2}\,\frac{C N^{-1/120}\|F_1\|_{\ell^2}\|F_2\|_{\ell^2}}N =C\Kint N^{-1/120}\sqrt{\alpha_{{\rm f},1}\alpha_{{\rm f},2}}, \end{align*} where $\alpha_{{\rm f},i}=(D/\Lsc)\|F_i\|_{\ell^2}^2=(D/\Lsc)\#\{n\in A\cap I_{b+i-1}:n\equiv\mathfrak a_i\ (D)\}$ are the two fibre densities. The fibre modulus $D$ cancels. Since $D\le\Lsc$ (\cref{lem:scale-conditions}(vi)), $\alpha_{{\rm f},i}\le(D/\Lsc)(\Lsc/D+1)\le2$. Now average over $x\sim\varrho_{\rm pre}$ and $y\sim\bigotimes_{p\in U}\Unif(\Om)$. The labels $(x_u,y_u)$ are uniform on $X_{\rm pre}\times X_U$, so the class $\mathfrak a_1$ is uniform among the $D_{\rm pre}q_U$ classes modulo $D$ above $s$, and $\E\alpha_{{\rm f},1}=\Mzero\#\{n\in A\cap I_b:n\equiv s\ (\Mzero)\}/\Lsc \le\Mzero\Kint\alpha$. Hence $\E(\alpha_{{\rm f},1}\alpha_{{\rm f},2})\le2\E\alpha_{{\rm f},1}\le2\Mzero\Kint\alpha$; no independence of the two classes is used. For the high part, Cauchy--Schwarz and Jensen's inequality ($\|g_1\|_2^4\le\E|g_1|^4$ over $X_{\mathcal S'}$) give $\E(\|g_1\|_2^2\|g_2\|_2^2)\le\|G_u\|_4^2\|G_v\|_4^2\le C_\epsilon N^\epsilon\alpha$, because $(x_u,y_u)$ together with the uniform outside label is uniform on $G_N$. Since $\|E_U\varphi_x\|_2^2=\E_y|E_U\varphi_x(y)|^2$ and $|\Psi|^2\le2|\Psi_{\le H}|^2+2|\Psi_{>H}|^2$, \[ \int\|E_U\varphi_x\|_2^2\,d\varrho_{\rm pre}(x)\le4C^2\Kint^3\Mzero N^{-1/60}\alpha +2H^{-2/3}C_\epsilon N^\epsilon\alpha\le C'_\epsilon N^{-1/60+\epsilon}\alpha , \] uniformly in $U$. \emph{Step 4: summation.} Distinct sets $U$ have distinct products, and $0<\gamma<1/2$, so $\sum_{q_U\le T_0}q_U^{-2\gamma}\le1+T_0^{1-2\gamma}/(1-2\gamma)$. Inserting Steps~2 and~3 into Step~1, \[ \Big|\int\prod_wG_w\,d\varrho\Big|\le C_\epsilon N^\epsilon\alpha \big(N^{-\gamma t_{\rm an}}+N^{-1/120+t_{\rm an}(1/2-\gamma)}\big). \] Take $\epsilon=72\delta$; both exponents are below $-\sigma$ by (S2) and (S3), which proves the lemma. \end{proof} At a nonunit clique or external-index difference the kernel is applied in the root-class form of \cref{prop:record:kernel20}(iii), which keeps every pinned prime in the modulus. Its constants satisfy the same uniform bounds. For the odd prefix with a unit external index, \cref{prop:record:kernel20}(ii), where an even-valuation square is divided out of the modulus, may be used in place of (iii). The fourth moment enters with the exponent exactly $1/2$, and no strict inequality between moment exponents is needed. \begin{lemma}[Large products with a density factor] \label{lem:record:density-lp} Let $(\eta_\Blk)$ be nonnegative numbers indexed by the atoms of all scales, with $\Pi_{\rm H}=\prod_\Blk(1+\eta_\Blk q_\Blk^{1/4})<\infty$, where $q_\Blk$ is the product of the primes of $\Blk$ with $e_p=1$. For $\epsilon>0$ there is $C_\epsilon$ with the following property. Let $\Lsc\ge1$ with $\Lsc\ge10N^{6\beta}$, $c\ge1$, and for every set $E\subseteq\mathcal A_N$ with $q_E>N^\tau$ let $\kappa'_E$ be a finite nonnegative measure on $G_N^V$ with $\kappa'_E(1)\le c\prod_{\Blk\in E}\eta_\Blk$ whose one-slot marginals are multiples of the uniform law, and let $(G^E_v)_v$ be inputs $g^{I,D_0,s}$ of \cref{def:record:functional}, possibly averaged over indices by a probability law. Then \[ \sum_{E:\,q_E>N^\tau}\Big|\int\prod_vG^E_v(z_v)\,d\kappa'_E(z)\Big| \le c\,C_\epsilon\Pi_{\rm H}N^{-\tau/4+\epsilon}\alpha . \] The same bound holds if the term of $E$ is replaced by $a_E(I_E^+I_E^-)^{1/2}$ with $0\le a_E\le c\prod_{\Blk\in E}\eta_\Blk$ and $I_E^\pm$ energies of such inputs under probability measures with uniform one-slot marginals. With $\epsilon=\ell_0$ the right-hand side is at most $c\,C\,\Pi_{\rm H}\Lsc^{-\sigma}\alpha$, by (S4). \end{lemma} \begin{proof} For fixed $E$ and indices, H\"older's inequality with $72$ factors in $L^{72}(\kappa'_E)$ and the uniform marginals give $|\int\prod_vG_v\,d\kappa'_E|\le\kappa'_E(1)\prod_v\|G_v\|_{L^{72}(G_N)}$; after averaging over the indices, H\"older over their law gives the same product of averaged norms. By \cref{lem:record:lift-moments}(c) with moments of order $72$, each norm is at most $(C_\epsilon N^\epsilon\Mzero^{72}\Kint\alpha)^{1/72}$, so the product is $C_\epsilon N^\epsilon\alpha$: the density exponents are $72/72=1$. The same bound holds for $I_E^\pm$, hence for $(I_E^+I_E^-)^{1/2}$. Finally, by Rankin's trick, \[ \sum_{E:\,q_E>N^\tau}\prod_{\Blk\in E}\eta_\Blk\le N^{-\tau/4}\sum_E \prod_{\Blk\in E}\eta_\Blk q_\Blk^{1/4}\le N^{-\tau/4}\Pi_{\rm H}. \] \end{proof} In the comparison proof the coefficient $\eta_\Blk$ of an atom is taken to be the sum of the prices at $\Blk$ listed in (CP8)(c), after the operator-to-energy reduction (\cref{lem:record:rec}(ii), \cref{def:cp8}); a spectral price entering the sum is the price produced by this reduction, not the total variation of the original signed law. The product $\Pi_{\rm H}$ is then finite by the summability (c) of \cref{def:cp8}: the atoms below $\Pfour$ are finitely many, each with a finite factor in $\Pi_{\rm H}$, and at a tail prime $p$ the prices of the selected laws are $s_p$, $a_p$ and the matching prices $T_{{\rm L},p}=T_{{\rm R},p}$, which add up to at most three times $s_p+a_p\le C_{\rm tail}p^{-3/2+2a}$, so that their sum weighted by $p^{1/4}$ converges (\cref{lem:tail-prices}(iii), (iv)). \subsection{From \texorpdfstring{$\Theta<1$}{Theta<1} to \texorpdfstring{$s(N)\le CN^{1-a/71}$}{s(N) <= C N\textasciicircum (1-a/71)} (baseline induction)}\label{subsec:scale:induction} It remains to convert a closing inequality at a least counterexample into a bound for every $A$. The theorem does this by induction on the scale: if a least counterexample would satisfy $Y\le\Theta Y$ with $\Theta(0)<1$ and only the two allowed kinds of remainder, then no counterexample exists and $Y\le C\Lsc^{-a}\alpha^\theta$ holds in general. \begin{theorem}[Linear-density induction]\label{thm:record:lineardensity} Let $00$ and a function $\Theta:[0,z_0]\to[0,\infty)$, continuous at $0$ with $\Theta(0)<1$, such that the following recurrence hypothesis holds. \begin{enumerate}[label=(Rec)] \item Let $C_0\ge1$, let $(\Lsc,A)$ be a least normalized counterexample for $(a,\theta,C_0)$ with $\Lsc\ge\Lsc_1$, and let $z\in[0,z_0]$. If every structured energy that the recurrence bounds at $(\Lsc,A)$ satisfies $|\mathfrak E|\le(1+z)\|\rho\|\,\Pi\,\Yf(\Lsc,A)$ with its coarse price $\Pi$, and the sum of the absolute values of its cancellation and large-product remainders is at most $z\,\Yf(\Lsc,A)$, then $\Yf(\Lsc,A)\le\Theta(z)\,\Yf(\Lsc,A)$. \end{enumerate} Suppose further that these remainders consist of a number, bounded independently of $\Lsc$ and $A$, of integrals of the form bounded in \cref{lem:record:density-can}, integrated against probability laws of the indices and multiplied by coefficients bounded independently of $\Lsc$ and $A$, together with finitely many sums of the form bounded in \cref{lem:record:density-lp}, whose number and whose constants $c$ and $\Pi_{\rm H}$ are independent of $\Lsc$ and $A$. Then there is $C$ with \[ \Yf(\Lsc,A)\le C\,\Lsc^{-a}\alpha^\theta \] for every $\Lsc\ge1$ and every square-difference-free $A\subseteq[\Kint\Lsc]$. Consequently $\alpha^{72-\theta}\le C\Lsc^{-a}$, and $s(N)\le C'N^{1-a/(72-\theta)}$ for every $N\ge1$. At $\theta=1$ the conversion is $\eps=a/71$. \end{theorem} \begin{proof} Let $C_{\rm R}$ be a constant with: the remainders at any least normalized counterexample $(\Lsc,A)$ with $\Lsc\ge\Lsc_*$ have total absolute value at most $C_{\rm R}\Lsc^{-\sigma}\alpha$. It exists by \cref{lem:record:density-can,lem:record:density-lp} and the hypothesis on their number and coefficients, and it does not depend on $C_0$, because the remainders do not involve the induction. \emph{Choice of constants.} By continuity choose $z_1\in(0,z_0]$ with $\Theta(z)\le(1+\Theta(0))/2<1$ for $0\le z\le z_1$. Choose $\Lsc_0\ge\max(\Lsc_1,\Lsc_*)$ such that $u_\Lsc\le z_1/2$ and $(C_{\rm dc}+C_{\rm R})\Lsc^{a-\sigma}\le z_1/2$ for $\Lsc\ge\Lsc_0$; this is possible because $a<\sigma$. For the finitely many $\Lsc<\Lsc_0$, every retained coefficient of $F_A$ has modulus at most $\alpha$, so $|F_A|\le n_\Lsc\alpha$, with $n_\Lsc$ the number of retained characters of $G_N$, and $\Yf(\Lsc,A)\le(n_\Lsc\alpha)^{72}\le n_\Lsc^{72}\alpha$. Put $C_{\rm base}=\max_{\Lsc<\Lsc_0}n_\Lsc^{72}$ and $C_0=\max(1,C_{\rm base}\Lsc_0^a)$. Then $\Yf(\Lsc,A)\le C_{\rm base}\alpha\le C_0\Lsc^{-a}\alpha^\theta$ for $\Lsc<\Lsc_0$, since $\alpha\le\alpha^\theta$. \emph{The least counterexample.} Suppose the bound $\Yf(\Lsc,A)\le C_0\Lsc^{-a}\alpha^\theta$ fails for some pair, and let $\Lsc$ be the least scale at which it fails, for some $A$. Then $(\Lsc,A)$ is a least normalized counterexample, $\Lsc\ge\Lsc_0$, $\alpha>0$ and $Y=\Yf(\Lsc,A)>0$. By \cref{prop:record:density-structured}, every structured energy satisfies $|\mathfrak E|\le(1+u_\Lsc+C_{\rm dc}\Lsc^{a-\sigma}\alpha^{1-\theta}/C_0) \|\rho\|\Pi Y\le(1+z_1)\|\rho\|\Pi Y$, because $\alpha\le1$ and $C_0\ge1$. The remainders are at most $C_{\rm R}\Lsc^{-\sigma}\alpha=(C_{\rm R}/C_0)\Lsc^{a-\sigma}\alpha^{1-\theta} \cdot C_0\Lsc^{-a}\alpha^\theta0$, and $|A|=\alpha N\le C_0^{1/(72-\theta)}\Kint^{a/(72-\theta)}N^{1-a/(72-\theta)}$. For an arbitrary $N\ge\Kint$ put $N'=\Kint\lceil N/\Kint\rceil<2N$; a square-difference-free subset of $[N]$ is one of $[N']$, which gives $s(N)\le C'N^{1-a/(72-\theta)}$. For $N<\Kint$, $s(N)\le N\le\Kint$. \end{proof} The hypothesis (Rec) is supplied by the comparison theorem: in the proof of \cref{thm:comparison}, \cref{lem:record:rec} shows that (Rec) holds for the density exponent $\theta$ of the frame data, with $\Theta(z)$ the closing number of \cref{thm:comparison} evaluated with every energy bound inflated by the factor $1+z$ and every remainder bounded by $zY$; it also proves the continuity at $z=0$ and that the remainders have the forms of \cref{lem:record:density-can,lem:record:density-lp}. In the baseline theorem $\theta=1$, and $\Theta(0)$ is the certified closing value. The induction uses only the moments of orders $2$, $4$, $72$, $140$ and $142$, and no limit in an interpolation parameter. \begin{remark}[Fixed parameters]\label{rem:fixed-parameters} Every statement and proof of \cref{sec:scale-comparison} holds for an arbitrary fixed integer $\Kint\ge2$, with the least square step \eqref{eq:square-step}, and for arbitrary fixed even exponents $e_p=2m_p$ at the clique primes, and so do the statements of Part~II that it uses: the functional is defined for these data (\cref{def:record:functional}); the index averages hold for every $\Kint\ge2$ (\cref{lem:twointerval}); the moment constants depend on the prefix only through $Q_{\rm cl}$ (\cref{lem:record:lift-moments}(c)); conductor decay allows any finite prefix (\cref{lem:record:prefix-conductor}), and the pair-support decay involves only the tail primes (\cref{lem:tr:pairsupport}); and the kernel allows any $m_p$, with constants depending on $\prod_{p\in\mathcal P_1}p^{e_p}$ (\cref{prop:record:kernel20}(iii), \cref{lem:kernel-depth-classes}). Constants and the starting scale depend on these fixed data, and nothing is asserted uniformly as $\Kint$ or the prefix grow with $N$. Each interval pair $I_b,I_{b+1}$ with $1\le b<\Kint$ is ordered, which, with their common length $\Lsc$, is all that the cancellation uses of the intervals, and the child scales are strictly smaller by \cref{lem:record:fibre-scale}(d). The baseline theorem uses $\Kint=\PushK$, $e_p=2\mcl$ with $\mcl=8192$ at the class-one primes below $\Pfour$, $\theta=1$ and the price exponent $a=\PushA$, which satisfies the gate $a<\sigma$ of \cref{thm:record:lineardensity}, with $\sigma-a=65195254/201416015625$, and gives $\eps=a/71=\PushExponent$. The gates of the analytic transfer that involve $a$ (the analytic, density, fixed-index and fixed-prefix gates, \cref{cert:record:analytic-stage}(S0)) hold on the whole range $0C_0\Lsc^{-a}\alpha^\theta$ through the sparse-set bound $Y\le C_\epsilon\Lsc^\epsilon\alpha^s$ (every $\epsilon>0$), $s=(10^6-36)/(10^6-1)$, which follows from H\"older, Parseval and a moment of order $2\cdot10^6$ by interpolation. This needs the sparse gate $as/(s-\theta)<\sigma$, which allows exactly $\theta0$ there. Energies whose selected atoms have a union $E$ with $q_E\le N^\tau$ are structured energies, bounded by their coarse prices (\cref{prop:record:density-structured}), with sharp bounds applied in the order of \cref{lem:record:folded-energy}. Every expansion over selected atoms also has terms with $q_E>N^\tau$; their sum is bounded by \cref{lem:record:density-lp}, with the post-reduction prices of the selected laws as the coefficients $\eta_{\Blk}$, and is $O(\Lsc^{-\sigma}\alpha)=o(1)Y$. Throughout, $o(1)$ denotes a quantity that tends to zero as $\Lsc\to\infty$, uniformly in $A$. Every $o(1)$ of this part is produced by structured energies and by the two kinds of analytic remainders, the large selections just described and the cancellations of \cref{lem:record:density-can}; this is the robustness of \cref{def:robust}, which is what the hypothesis (Rec) of \cref{thm:record:lineardensity} asks for (\cref{lem:record:rec}). At a least counterexample, fixing the labels at an atom $\Blk$ fixes residue classes, and splitting a class into progressions whose step is a square divisible by $q_{\Blk}$ returns the problem at a shorter scale (\cref{lem:record:fibre-scale}); by the induction hypothesis this costs the factor $(q_{\Blk}^2)^{a/d}$ at each of the $d$ slots. This is the origin of the prices. \begin{definition}[Prices]\label{def:price} Let $\Blk$ be an atom and $q_{\Blk}=\prod_{p\in\Blk}p$ its block modulus. Its \emph{selection factor} is $q_{\Blk}^{2a}$; for a prefix atom $\{p\}$ with $e_p$ even we read $q_{\Blk}^{2a}$ as $p^{e_pa}$, the factor of selecting the full group $\Z/p^{e_p}\Z$ (\cref{def:record:structured-energy}). \begin{enumerate}[label=(\alph*)] \item The \emph{price} of a finite signed measure $\zeta$ on $X_{\Blk}^V$ is $\|\zeta\|_{\rm var}\,q_{\Blk}^{2a}$: selecting $\Blk$ changes every slot. \item Let $c\in\mathfrak F$ be a cut, $\kappa$ a nonnegative measure on $X_{\Blk}^V$ of mass $w$ and $\zeta$ a signed measure on $X_{\Blk}^V$. Then $\zeta$ has \emph{sharp bound $d_\zeta$ relative to $\kappa$ at $c$} if, for a probability law $\pi$ on a finite set of shared labels, $\kappa=w\int\kappa_s\,\pi(ds)$ and $\zeta=w\int K_s\,\pi(ds)$ with probability measures $\kappa_s$ and signed measures $K_s$ that satisfy \eqref{eq:record:sharp} at $c$ relative to the half marginals of $\kappa_s$, with the constant $d_\zeta$, for every $s$. The \emph{sharp price} of $\zeta$ is $w\,d_\zeta\,q_{\Blk}^{2a}$. More generally an \emph{operator price} is a weight, times an operator norm relative to actual half marginals, times $q_{\Blk}^{2a}$. \item An \emph{upper price} is any number at least the price. A \emph{total} is a sum of prices over the atoms of $\mathcal A$. In an expansion over selected atoms each selected atom is charged its price once per expanded term. \end{enumerate} \end{definition} The unpriced part of a price (a mass, a weight, a weighted norm) does not depend on the exponent, and an atom's laws do not depend on the scale; so a total over $\mathcal A$ bounds the corresponding sum over $\mathcal A_N$ at every scale. \begin{lemma}[Repricing]\label{lem:record:repricing} Let $00$, and with $|I_\Blk|=1$, $c_{\Blk,1}=1$ at all but finitely many atoms of $\mathcal A$, such that: \begin{enumerate}[label=(\alph*)] \item\emph{Acceptance.} Every query of $\mathcal E_k$ is accepted by every component: $\nu_{\Blk,i}(1)>0$ and, $\nu_{\Blk,i}$-almost surely, for every $e$, the difference $z_{v_e}-z_{u_e}$ is a nonzero square at every prime of $\Blk$ with $e_p=1$, and at a prefix prime it is nonzero, of even valuation $2j0$, $\Lsc_1$ and a function $c(\cdot)$ on $[0,z_0]$, continuous at $0$ with $c(0)=c$, such that $\Xi\le c(z)Y$ at every $z$-inflated least normalized counterexample with $\Lsc\ge\Lsc_1$ and $z\le z_0$. \end{enumerate} Robust lower bounds $\Xi\ge(c-o(1))Y$ are defined in the same way. A family of bounds is robust \emph{uniformly} if one argument, one $z_0$ and $\Lsc_1$, and one modulus of continuity at $0$ serve for all of them; in particular the remainders of the whole family together satisfy (a). \end{definition} A robust bound holds with $o(1)$ in the ordinary sense. By \cref{prop:record:density-structured}, every least normalized counterexample with $\Lsc$ large is $z$-inflated with $z=u_\Lsc+(C_{\rm dc}+C_{\rm R})\Lsc^{a-\sigma}$, which tends to zero uniformly in $A$ because $a<\sigma$ and $C_0\ge1$; here $C_{\rm R}$ bounds the remainders allowed by (a), through \cref{lem:record:density-can,lem:record:density-lp}, as in the proof of \cref{thm:record:lineardensity}. \begin{definition}[(CP8) Admissibility, robustness, summability]\label{def:cp8} \leavevmode \begin{enumerate}[label=(\alph*)] \item\emph{Admissibility.} Every law named in (CP2)--(CP6) (the positive records of (CP2)(a), the records $\kappa_{\Blk,i},\kappa'_{\Blk,i}$, the records of $\Nbr_{0,\Blk}-\mu_{\Blk}$, the laws $D^\epsilon_{\Blk,t}$ and the records of $M_{s,\Blk}-\Nbr_{\Blk}$) is admissible, and so is every selected law that the reductions of this part produce from them; every reduction of this part satisfies (O3) and (O4) of \cref{def:admissible}. \item\emph{Robustness.} The bounds of (CP5) and (CP7) are robust (\cref{def:robust}), those of (CP5) uniformly in the class. \item\emph{Summability.} With $q_{\Blk}$ here denoting the product of the primes of $\Blk$ with $e_p=1$ only (so the weight $q_{\Blk}^{1/4}$ is $1$ at a prefix atom, whose prices in \cref{def:price} nevertheless carry the factor $p^{e_pa}$), $v_\Blk=\sum_iv_{\Blk,i}$ and $d_\Blk=\sum_id_{\Blk,i}$ as in (CP2), $s_{\Blk},a_{\Blk}$ as in (CP4) and the auxiliary prices of (CP5), \[ \sum_{\Blk\in\mathcal A}q_{\Blk}^{1/4}\Bigl(p_{\Blk}+v_{\Blk}+d_{\Blk} +u_{\Blk}+s_{\Blk}+a_{\Blk}+T_{{\rm L},\Blk}+T_{{\rm R},\Blk} +\sum_{j\in J_\Blk}y_{\Blk,j}\Bigr)<\infty . \] \end{enumerate} \end{definition} Part (c) makes the totals $P$, $V$, $D$ (and the tag totals), $U_0$, $S$, $A$, $T$ and the totals of the auxiliary prices finite and independent of the scale, and it makes the product $\Pi_{\rm H}$ of \cref{lem:record:density-lp} finite for the coefficients that the expansions produce: these are post-reduction prices of the selected laws, and only the tail atoms form an infinite family. A bound is shown to be robust by the criterion of \cref{lem:record:rec}(i): it is built from structured-energy bounds by sums, products and monotone operations, or it is an exact relation minus such bounds, and every strict inequality it needs holds strictly at $z=0$. \subsection{Theorem~C: if \texorpdfstring{$\Theta<1$}{Theta<1} then \texorpdfstring{$s(N)\le C'N^{1-a/(72-\theta)}$}{s(N) <= C' N\textasciicircum (1-a/(72-theta))}}\label{subsec:cp:theorem} \paragraph{How to read the statement.} Theorem~C is conditional: it assumes laws satisfying (CP0)--(CP8) and concludes the power saving from the single numerical inequality $\Theta<1$. The symbols in $\Theta$ are: $d=72$ slots and $k$ queries ($k=6$ in Part~V); $L_0$ the total price of $\mu\to\lambda$ (CP2); $B$ the energy factor of the law dominating $\lambda$ (CP3); $S,A$ the total symmetric and skew prices of $\nu-\lambda$ (CP4), with $\hat S,\hat A$ any finite upper bounds for them; $\mathcal E$ any number at least $\Psi(\hat\pi,\hat y)$, where $\Psi$ is a \emph{complete polynomial}---a power series with nonnegative coefficients dominating every simultaneous-change bound, defined in \cref{rem:cp:monotone} below and constructed in \cref{lem:record:record-expansion} (without (CP5) families, $\Psi(\hat\pi)=B(e^{\hat S}\cosh\hat A-1)$; the simpler display $\mathcal E=B(e^S\cosh A-1)-D$ in \cref{subsec:intro:inequality} is the Part~V evaluation with savings $D$ subtracted); $T$ the total price of the dominators for $\nu$ (CP6), entering through $e^T$; $R_I$ the conductor factor of one index (\cref{def:hyb:coupled}); $m$ the mean-energy lower bound (CP7), whose trivial admissible value is $1-L_0$ (\cref{lem:record:domination}); and $J,W$ as displayed. Hatted quantities are certified upper bounds: by monotonicity (\cref{rem:cp:monotone}) the theorem may be applied with upper bounds for prices and a lower bound for $m$. Note $0<\theta\le1$ in (CP0): the improved exponent $\vartheta=\FourRoutesDensity>1$ of \cref{thm:main} is not obtained by substituting $\vartheta$ for $\theta$ here, but by the separate induction of \crefrange{sec:density:moments-prefix}{sec:four-routes-closing}. In (CP4) the letter $\omega$ denotes a \emph{selection} (a choice of changed records), not the random index $\omega$ of \cref{def:hyb:coupled}; the context (prices versus intervals) distinguishes them. \begin{theorem}[Theorem~C. If $\Theta<1$ then $s(N)\le C'N^{1-a/(72-\theta)}$]\label{thm:comparison} Let comparison data satisfy (CP0)--(CP8) at every scale. Let $\hat\pi\ge\pi$ be upper prices for the records of (CP4), with totals $\hat S\ge S$ and $\hat A\ge A$ finite; let $\hat y\ge y$ be upper auxiliary prices of (CP5), of finite total $\sum_{\Blk,j}\hat y_{\Blk,j}$; let $\Psi$ be a complete polynomial of \cref{lem:record:record-expansion}(ii) for the classes and class bounds of (CP5) (for instance in the completed form (iv) or the replaced form (v) of that lemma) that converges at $(\hat\pi,\hat y)$, and let $\mathcal E\ge\Psi(\hat\pi,\hat y)$. Put \begin{gather*} J=Be^T\Bigl(\frac{R_I}2\Bigr)^k,\qquad W=Be^{S+A}\Bigl[\Bigl(1+\frac{R_I}{2\Kint^{1-2\theta/d}}\Bigr)^k-1\Bigr],\\ \Theta=\bigl(1-2^{-k}\bigr)\bigl(L_0+\mathcal E\bigr)+J+W+\frac{1-m}{2^k}. \end{gather*} If $\Theta<1$, there is a constant $C$, depending only on the comparison data, such that $\Yf(\Lsc,A)\le C\Lsc^{-a}\alpha^\theta$ for every $\Lsc\ge1$ and every square-difference-free set $A\subseteq[\Kint\Lsc]$, $\alpha=|A|/(\Kint\Lsc)$. Consequently \[ s(N)\le C'N^{1-a/(d-\theta)}\qquad\text{for every }N\ge1 . \] \end{theorem} The proof is in \cref{sec:comparison-proof}. Without classes, the complete polynomial of \cref{lem:record:record-expansion}(ii) is $\Psi=B(e^{S(x)}\cosh A(x)-1)$ and $\Psi(\hat\pi)=B(e^{\hat S}\cosh\hat A-1)$; a class replaces $B$ times its monomials by its class bounds. \begin{remark}[Monotonicity]\label{rem:cp:monotone} $\Theta$ is nondecreasing in $L_0$, $\mathcal E$, $B$, $S$, $A$, $T$ and $R_I$, and nonincreasing in $m$: $1-2^{-k}>0$, $J$ is nondecreasing in $B$, $T$ and $R_I$, and $W$ in $B$, $S+A$ and $R_I$, all of these being nonnegative. A complete polynomial is any power series with nonnegative coefficients that dominates, coefficient by coefficient, the series $\sum_\omega b_\omega$ of \cref{lem:record:record-expansion}(ii), in which a selection in no class contributes $B$ on its monomial, a selection of a class with a class cost that cost on its monomial, and a selection of a class with class bounds its class bound. So every power series with nonnegative coefficients dominating these, for instance one built from certified upper bounds for $B$, for the class costs and for the coefficients of the class bounds, gives an admissible $\mathcal E$ when it is evaluated at upper prices and upper auxiliary prices. Hence the theorem holds with certified upper bounds for $L_0$, $B$, $S$, $A$, $T$, $R_I$, the prices, the auxiliary prices, the class costs and the coefficients of the class bounds, and a certified lower bound for $m$, in place of the quantities themselves; this is how the closing of Part~V evaluates $\Theta$. \end{remark} \begin{remark}[Reading the closing number]\label{rem:cp:reading} The sum $L_0+\mathcal E$ bounds $|Y_\nu-Y_\mu|/Y$ up to $o(1)$, and since the empty term of the signed-index expansion is $Y_\nu$ itself, the bound $L_0+\mathcal E$ enters $\Theta$ with the coefficient $(2^k-1)/2^k$ (see the opening of \cref{sec:comparison-lemmas}). In $J$ each query contributes $R_I/2$; $W$ bounds the terms in which every query to which the coupled transition, rather than the average, is applied in that term wraps; and $m>1$ lowers $\Theta$ through $(1-m)/2^k$. In the baseline application $k=6$, $d=72$, $\theta=1$, so $1-2^{-k}=63/64$ and $\Kint^{1-2\theta/d}=\Kint^{35/36}$ with $\Kint=\PushK$, giving $\eps=a/71$ and $\Theta<\PushTheta$ (\cref{sec:closing}). These are baseline values, quoted here only as an illustration; Theorem~C itself uses no Part~V number. \end{remark} \paragraph{Consequences and what to read next.} From Part~II: the slot array and its cuts (\cref{lem:slot-array}, \cref{def:sorting}), the cut calculus (\cref{def:cc:order}, \cref{eq:cc:bilinear}, \cref{rem:cut-symmetries}, \cref{lem:commoncut}, \cref{lem:record:block-gram}), the functional and its inputs (\cref{def:record:functional}, \cref{lem:twointerval}), the reference hypotheses (\cref{hyp:record:reference}), the square shift (\cref{lem:square-shift}), the sector lemma (\cref{lem:sector}), and the analytic notions of \cref{def:record:analytic-stage,def:record:counterexample,def:record:structured-energy,def:admissible}, \cref{eq:record:sharp}, \cref{lem:record:density-can,lem:record:density-lp}. \space % End sections/09_comparison_theorem % Begin sections/10_comparison_lemmas \makeatletter \providecommand{\setprimedlabel}[1]{\protected@edef\@currentlabel{#1}} \makeatother \section{Five estimates at a least counterexample} \label{sec:comparison-lemmas} \paragraph{What this section proves and how to read it.} The comparison theorem (\cref{thm:comparison}) reduces the baseline theorem to the inequality $\Theta<1$ between finitely many prices. Its proof, in the next section, composes five inequalities proved here at a least normalized counterexample: the first comparison $Y_\lambda\ge(1-L_0-o(1))Y$ (\cref{lem:record:first-stage}); the reserved cost $|Y_\nu-Y_\lambda|\le(\mathcal E+o(1))Y$, with $\mathcal E$ a complete polynomial in the prices and the auxiliary prices (\cref{lem:record:record-expansion}); the wrap $|J_\nu-2^kY_\nu|\le(2^kW+o(1))Y$ (\cref{lem:record:wrap-expansion}); the index-support inequality $J_\nu\le Y_\nu+\frac12[(V_{\rm L}-e_{\rm L})+(V_{\rm R}-e_{\rm R})]$ (\cref{lem:record:common-mean,cor:index-support-frame}); and the envelope bound $V_{\rm L},V_{\rm R}\le(2^kJ+o(1))Y$ (\cref{lem:envelope-energy}). They rest on one calculus of energies under the reserved Gram bracket (\cref{lem:sharp-first,lem:bracket-energy,lem:energy-toolkit}), which Part~V uses as well: for the variance credits and envelope class bounds of (CP5), together with the variance form of \cref{lem:record:variance-interface} (\cref{lem:var-gain,prop:background-variance,lem:class-credit,thm:envelopes,cor:envelope-costs}), for the mean credit (CP7) (\cref{prop:record:mean-credit}), and in the closing, which evaluates the complete polynomial (\cref{cert:closing}). Every statement uses only the frame data and the hypotheses of \cref{thm:comparison} that it lists, and Part~II; none refers to a particular local law. \paragraph{How the inequalities fit together.} The reference $\mu$ is reflection positive at every cut and defines $Y=Y_\mu$. The first-stage law $\lambda$ is a law that dominates $\mu$ in the cut order at one cut of the family, plus record differences grouped in tags, each sharp at the cut of its tag, so it loses only $L_0$. The comparison law $\nu$ accepts every query and is a finite signed combination of nonnegative accepting laws, but it is not reflection positive; the reserved Gram bracket controls it record by record. The signed index form $J_\nu$ of \eqref{eq:record:expansion} carries the constant coefficient $2^k$ on $Y_\nu$, and every other term of its expansion couples a nonempty set of queries and cancels by the actual-square kernel unless all its intervals wrap. On the other side, $J_\nu$ is bounded by the random-inclusion energies of the matching envelopes. Decompose by the exact support of the index functions: the component of $J_\nu$ with empty support is $Y_\nu$ itself, and that of each energy is the mean energy of the envelope, which dominates $Y_\lambda$. Keeping these two components exactly, rather than bounding $J_\nu$ by the full envelope energies without subtracting their mean energies, saves one of the $2^k$ copies of the reserved comparison cost: in $\Theta$ the coefficient of $\mathcal E$ is $1-2^{-k}$, while the matching term and the wrap keep coefficient one (\cref{lem:record:domination}). The index step bounds each half-function only under its own envelope and uses no symmetry of $\nu$ and no odd-skew cancellation; skewness enters only through the exact identity of the empty component. \paragraph{Conventions.} Notation, energies $Y_\kappa$, the least normalized counterexample and $o(1)$ are those of the previous section: atoms are written $\Blk$, $B=e^{U_0}+R_{\rm err}$, $\Nbr_\Blk=\Nbr_{0,\Blk}=\lambda_\Blk=\mu_\Blk$ off the first-stage atoms, $d=|V|=72$, $(\Lsc,A)$ is a least normalized counterexample with $\Lsc$ larger than the thresholds of the lemmas used in this section (every $o(1)$ is as $\Lsc\to\infty$) and $Y=Y_\mu>0$. A positive measure on the labels $X_X^V$ of a finite set $X$ of atoms is \emph{admissible} in the sense of \cref{def:admissible}: its one-slot marginals are multiples of the uniform law, it does not depend on the indices, and every sharp bound applied to it is uniform in the shared labels (on one atom, its normalization is a positive record). Prices are those of \cref{def:price}, and $C_X=\prod_{\Blk\in X}q_\Blk^{2a}$ is the price of selecting every atom of $X$. \paragraph{Remainders.} Every bound below is robust in the sense of \cref{def:robust}: its $o(1)$ is a finite sum, with coefficients bounded independently of $\Lsc$ and $A$, of \emph{energy errors} (the relative error of \cref{prop:record:density-structured}, multiplying a structured-energy bound once), \emph{cancellation remainders} (integrals of the form bounded in \cref{lem:record:density-can}) and \emph{large-product remainders} (the terms of an expansion whose union $E$ of selected atoms has $q_E>N^\tau$, bounded together by \cref{lem:record:density-lp} with the post-reduction prices of the selected laws as coefficients). Each statement lists which kinds occur; this is what \cref{lem:record:rec}(ii) uses. \paragraph{Fixed selections and summed remainders.} An individual asymptotic bound below with a selected set $X$ is a bound for fixed $X$; its large-product remainder need not be uniform as $X$ varies. In a sum over selections we first expand the outside laws and split by the \emph{full} union $E$ of selected atoms. On $q_E\le N^\tau$ the structured-energy error is uniform in $E$ and its labels. All terms with $q_E>N^\tau$ are instead summed by \cref{lem:record:density-lp}, with their post-reduction coefficients. Thus no summed argument below uses a pointwise $o(1)$ for an arbitrary large selected set. For fixed $X$, the same procedure also proves the individual asymptotic statements: if $Z$ is the further selected set, then \[ \sum_{Z:\,q_Xq_Z>N^\tau}\prod_{\Blk\in Z}\eta_\Blk \le N^{-\tau/4}q_X^{1/4} \prod_\Blk(1+\eta_\Blk q_\Blk^{1/4}). \] The factor $q_X^{1/4}$ is fixed in that assertion. When $X$ varies in a priced expansion it is included in the full union before Rankin's inequality is applied, and (CP8)(c) bounds the resulting product. \subsection{Bounding a bilinear form by energies of random restrictions} The small primes enter the comparison only through the external index. The next lemma is the inequality behind every index estimate: the one-cut coupling inequality, the bound of the signed index form by random-inclusion energies, and the common mean are its cases. \begin{lemma}[Index-support lemma] \label{lem:record:common-mean} Let $\mathcal X_+$ be a finite set, and $M_{\rm L}$, $M_{\rm R}$, $\Gamma$ real matrices indexed by $\mathcal X_+\times\mathcal X_+$, with $M_{\rm L},M_{\rm R}$ symmetric and \begin{equation}\label{eq:record:joint-gram} \begin{pmatrix}M_{\rm L}&\Gamma\\ \Gamma^{\mathsf T}&M_{\rm R}\end{pmatrix} \succeq0 . \end{equation} Let $\Omega=\prod_{j\in\mathcal K}\Omega_j$ be a finite product of finite sets with the uniform probability measure. On coordinate $j$, let $E_{j,0}\le\cdots\le E_{j,h_j}=I$ be a chain of conditional-expectation projections, with $h_j\ge1$ and $E_{j,0}$ the projection onto constants. Put $\Pi_{j,0}=E_{j,0}$, $\Pi_{j,l}=E_{j,l}-E_{j,l-1}$ for $l\ge1$, and \[ H_{\boldsymbol l}=\bigotimes_{j\in\mathcal K}\operatorname{ran}\Pi_{j,l_j}, \qquad 0\le l_j\le h_j. \] Choose tails $1=\delta_{j,0}\ge\delta_{j,1}\ge\cdots\ge\delta_{j,h_j}\ge0$ and put $\delta_{\boldsymbol l}=\prod_j\delta_{j,l_j}$. Let $\mathcal T$ on $L^2(\Omega)$ preserve every $H_{\boldsymbol l}$, act as the identity on $H_{\boldsymbol0}$, and have norm at most $\delta_{\boldsymbol l}$ on $H_{\boldsymbol l}$. It acts componentwise on vector-valued maps. Independently of $\omega$, reveal independent depths $J_j\in\{0,\ldots,h_j\}$ with $\Pr(J_j\ge l)=\delta_{j,l}$, write $\Jc=(J_j)_j$, and set $Z^\Jc=(\bigotimes_jE_{j,J_j})Z$. For $X,Y\colon\Omega\to\R^{\mathcal X_+}$ put \begin{gather*} \mathsf J=\E_\omega\ip{X(\omega)}{\Gamma(\mathcal TY)(\omega)},\qquad e_{\rm L}=\ip{\E X}{M_{\rm L}\,\E X},\qquad e_{\rm R}=\ip{\E Y}{M_{\rm R}\,\E Y},\\ V_{\rm L}=\E_\Jc\E_\omega\ip{X^\Jc(\omega)}{M_{\rm L}X^\Jc(\omega)},\qquad V_{\rm R}=\E_\Jc\E_\omega\ip{Y^\Jc(\omega)}{M_{\rm R}Y^\Jc(\omega)} . \end{gather*} Then $V_{\rm L}\ge e_{\rm L}\ge0$, $V_{\rm R}\ge e_{\rm R}\ge0$, and \begin{enumerate}[label=(\alph*)] \item \begin{equation}\label{eq:record:common-mean} \bigl|\mathsf J-\ip{\E X}{\Gamma\,\E Y}\bigr| \le\tfrac12\bigl[(V_{\rm L}-e_{\rm L})+(V_{\rm R}-e_{\rm R})\bigr]; \end{equation} \item $|\mathsf J|\le V_{\rm L}^{1/2}V_{\rm R}^{1/2}$. \end{enumerate} The whole-coordinate case is $h_j=1$: identify $\Jc$ with the set of coordinates whose depth is one. Then $Z^\Jc=\E[Z\mid\omega_\Jc]$, each coordinate is included independently with probability $\delta_j=\delta_{j,1}$, and the sector indexed by $S=\{j:l_j=1\}$ is $H_S=\bigotimes_{j\in S}L^2_0(\Omega_j)\otimes\bigotimes_{j\notin S}\R\one$, with weight $\delta_S=\prod_{j\in S}\delta_j$. \end{lemma} \begin{proof} \emph{Factorization.} The diagonal blocks of \eqref{eq:record:joint-gram} are positive semidefinite, and $\Gamma=M_{\rm L}^{1/2}CM_{\rm R}^{1/2}$ with $\|C\|\le1$ (\cref{lem:record:block-gram}). Put $\|Z\|_M^2=\E_\omega\ip{Z(\omega)}{MZ(\omega)}$ for symmetric $M\succeq0$. Matrices acting on $\R^{\mathcal X_+}$ commute with $\mathcal T$ and with (conditional) expectations over $\omega$. \emph{Decomposition.} Nested orthogonal projections satisfy $E_{j,l}E_{j,l'}=E_{j,\min(l,l')}$. Their differences $\Pi_{j,l}$ are therefore mutually orthogonal projections summing to $I$. Tensorizing gives $L^2(\Omega)=\bigoplus_{\boldsymbol l}H_{\boldsymbol l}$, so componentwise $Z=\sum_{\boldsymbol l}Z_{\boldsymbol l}$ and $Z_{\boldsymbol0}=\E Z$. These components are orthogonal for every form $\E_\omega\ip{\cdot}{M\,\cdot}$ with $M\succeq0$, and \[ Z^\Jc=\sum_{\boldsymbol l:\,l_j\le J_j\ \text{for every }j}Z_{\boldsymbol l}. \] This is the depth version of the exact-support decomposition of \cref{lem:sector}. \emph{The form and its energy envelope.} Since $\mathcal T$ preserves the sectors, only equal sectors pair in $\mathsf J$. On the sector $H_{\boldsymbol l}$ the factorization gives \[ \bigl|\E_\omega\ip{X_{\boldsymbol l}}{\Gamma\mathcal TY_{\boldsymbol l}}\bigr| =\bigl|\E_\omega\ip{M_{\rm L}^{1/2}X_{\boldsymbol l}} {(C\otimes\mathcal T)M_{\rm R}^{1/2}Y_{\boldsymbol l}}\bigr| \le\delta_{\boldsymbol l}\|X_{\boldsymbol l}\|_{M_{\rm L}} \|Y_{\boldsymbol l}\|_{M_{\rm R}}. \] The zero-sector term is $\ip{\E X}{\Gamma\,\E Y}$. The same coefficient $\delta_{\boldsymbol l}=\Pr(J_j\ge l_j\ \text{for every }j)$ is the probability that the random projection retains this sector. Orthogonality therefore gives the energy identity \[ V_{\rm L}=\sum_{\boldsymbol l}\delta_{\boldsymbol l} \|X_{\boldsymbol l}\|^2_{M_{\rm L}} =e_{\rm L}+\sum_{\boldsymbol l\ne\boldsymbol0}\delta_{\boldsymbol l} \|X_{\boldsymbol l}\|^2_{M_{\rm L}}, \] and likewise for $V_{\rm R}$. In the whole-coordinate case this is \cref{lem:sector}(d). \emph{Conclusion.} For (a), sum the bound for the form over $\boldsymbol l\ne\boldsymbol0$ and use $2xy\le x^2+y^2$. For (b), sum over all $\boldsymbol l$ and apply Cauchy--Schwarz with weights $\delta_{\boldsymbol l}$. The energy identity also gives $V_s\ge e_s\ge0$ for $s\in\{{\rm L},{\rm R}\}$. \end{proof} \begin{remark}[The inclusion and depth laws] In the whole-coordinate special case, the inclusion law makes the energy exactly the norm envelope of the index operator: $\Pr(S\subseteq\Jc)=\delta_S$ turns the bound $\delta_S$ on $H_S$ into the weight of $H_S$ in $V_{\rm L}$ and $V_{\rm R}$. The proof uses only $\Pr(S\subseteq\Jc)\ge\delta_S$, and among such laws the independent one minimizes every moment later paid for the inclusions: for $w_j\ge1$, $\E\prod_{j\in\Jc}w_j=\sum_S\Pr(S\subseteq\Jc)\prod_{j\in S}(w_j-1) \ge\prod_j(1+\delta_j(w_j-1))$. For the finite-depth law of (CP0)(d), independence instead gives $\Pr(J_j\ge k_j\ \text{for every }j)=\prod_j\delta_{j,k_j}$. These joint tails give the sector weights in the filtration form of the lemma and the conductor moment $R_I$ of \cref{lem:hyb:moment}. \end{remark} The instructive base case is the plain coupling inequality, in which one positive form plays all three roles. \begin{corollary}[One-cut coupling inequality]\label{lem:hyb:coupling} In the whole-coordinate case of \cref{lem:record:common-mean}, let $C\succeq0$ be symmetric, $\|F\|_C^2=\ip F{CF}$, and let $T_j$ be doubly stochastic matrices on $\Omega_j$ with $\|T_jf\|\le\delta_j\|f\|$ for $f$ of mean zero. Let $\omega$ be uniform, $\Pr(\omega'=\eta\mid\omega)=\prod_jT_j(\omega_j,\eta_j)$, and $\Jc$ independent of $(\omega,\omega')$. With $\mathsf I=\E\ip{X(\omega)}{CY(\omega')}$ and $\mathsf V=\frac12\E_\Jc\E_\omega[\|X^\Jc\|_C^2+\|Y^\Jc\|_C^2]$, \begin{equation}\label{eq:hyb:coupling} \tfrac12\|\E X+\E Y\|_C^2-\mathsf V\ \le\ \mathsf I\ \le\ \mathsf V-\tfrac12\|\E X-\E Y\|_C^2 ; \end{equation} in particular $|\mathsf I|\le\mathsf V$. No relation between $\E X$ and $\E Y$ is assumed. \end{corollary} \begin{proof} $\E[Y(\omega')\mid\omega]=(TY)(\omega)$ with $T=\bigotimes_jT_j$. Each $T_j$ fixes the constants (its rows sum to one) and maps $L^2_0(\Omega_j)$ into itself (its columns sum to one), so $T$ satisfies the hypotheses on $\mathcal T$ (\cref{lem:sector}(a)). Apply (a) with $M_{\rm L}=M_{\rm R}=\Gamma=C$, for which \eqref{eq:record:joint-gram} holds as $\bigl(\begin{smallmatrix}C&C\\C&C\end{smallmatrix}\bigr)= \bigl(\begin{smallmatrix}1&1\\1&1\end{smallmatrix}\bigr)\otimes C$: since $\mathsf V=\frac12(V_{\rm L}+V_{\rm R})$, it gives $|\mathsf I-\ip{\E X}{C\,\E Y}|\le\mathsf V-\frac12(\|\E X\|_C^2+\|\E Y\|_C^2)$, which is \eqref{eq:hyb:coupling}. \end{proof} \begin{corollary}[The signed index form and the common mean] \label{cor:index-support-frame} Assume (CP0)(c),(d) of \cref{thm:comparison}. Let $\nu=\bigotimes_\Blk\nu_\Blk$ be a product of finite signed measures on the $X_\Blk^V$ (for instance the comparison law of (CP4)), and let $M_{{\rm L},\Blk}$, $M_{{\rm R},\Blk}$ be nonnegative measures with $\bigl(\begin{smallmatrix}M_{{\rm L},\Blk}&\nu_\Blk\\ \nu_\Blk^*&M_{{\rm R},\Blk} \end{smallmatrix}\bigr)\succeq_\iota0$ for every atom, as in (CP6). Let $J_\nu$ be the signed index form of \eqref{eq:record:expansion}, $X_\omega$, $Y_\omega$, $\bar X$ the half-functions of \cref{def:hyb:coupled}, $e_s=Q_{\otimes M_s}(\bar X,\bar X)$ for $s\in\{{\rm L},{\rm R}\}$, and $V_{\rm L}=V_{\otimes M_{\rm L}}(X)$, $V_{\rm R}=V_{\otimes M_{\rm R}}(Y)$ the single-half random-inclusion energies of \cref{def:hyb:coupled}. Then: \begin{enumerate}[label=(\roman*)] \item $\mathcal T=\bigotimes_e(2P_e-T_e)$, and likewise $\mathcal T^*$, maps every exact-conductor sector $H_S$ of the index space into itself, with $S$ a vector of conductor depths, is the identity on $H_{\boldsymbol0}$ and has norm at most $\delta_S$ on $H_S$; \item $\E_\omega X_\omega=\E_\omega Y_\omega=\bar X$, and for every value of $\Jc$, $X^\Jc_\omega$ carries $g^{I_{b_e},D_{\Jc_e},s_e\bmod D_{\Jc_e}}$ at $u_e$ and $F_A$ at the other slots of $V_+$, likewise $Y^\Jc_\omega$ at the slots $\iota v_e$; \item $V_s\ge e_s\ge0$, \begin{equation}\label{eq:index-support-frame} |J_\nu-Y_\nu|\le\tfrac12\bigl[(V_{\rm L}-e_{\rm L})+(V_{\rm R}-e_{\rm R})\bigr], \end{equation} and $|J_\nu|\le V_{\rm L}^{1/2}V_{\rm R}^{1/2}$. \end{enumerate} \end{corollary} \begin{proof} (i) The coordinates are the interval and the full prime-power residues of \cref{def:hyb:coupled}. Convolution preserves each exact conductor space, as does its adjoint. The interval has the two-sector chain of constants and their orthogonal complement, with tail one. On a conductor vector $S$, put $S_e$ for its coordinates belonging to query $e$. If $S_e=\boldsymbol0$, then $P_e=T_e=I$ on this sector. Otherwise $P_e=0$ and $2P_e-T_e=-T_e$, whose norm is bounded by the product of the tails belonging to $S_e$. Tensoring over queries proves (i), for both $\mathcal T$ and its adjoint. For whole-coordinate Bernoulli inclusion the same argument is the ordinary support proof. (ii) For uniform $(b,s)$, $\E_{b,s}g^{I_b,\Mzero,s}=F_A$, and conditioning a uniform residue on its revealed depths $\Jc_e$ turns $g^{I,\Mzero,s}$ into $g^{I,D_{\Jc_e},s\bmod D_{\Jc_e}}$, with $D_{\Jc_e}$ the product of the revealed prime powers (\cref{lem:twointerval}). The queries have pairwise disjoint endpoints and independent indices, so $X_\omega$ and $Y_\omega$ are products of functions of the independent $\omega_e$ at distinct slots, with $F_A$ at the remaining slots; expectations and conditional expectations factorize over $e$, and the interval coordinates lie in $\Jc$ with probability one. (iii) Let $M_{\rm L}$, $M_{\rm R}$, $\Gamma$ be the cut matrices at $\iota$ of $\bigotimes_\Blk M_{{\rm L},\Blk}$, $\bigotimes_\Blk M_{{\rm R},\Blk}$ and $\nu$; by \eqref{eq:cc:kron} and the tensorization of brackets (\cref{lem:record:block-gram}) they satisfy \eqref{eq:record:joint-gram}. Then $\mathsf J=J_\nu$, $\ip{\bar X}{\Gamma\bar X}=Y_\nu$, and the depth envelope of (CP0)(d) is that of the filtration form of \cref{lem:record:common-mean}; apply that lemma with (i) and (ii). \end{proof} \begin{remark}[Where the gain comes from] With $M_{\rm L}=M_{\rm R}=\Gamma\succeq0$, \cref{lem:record:common-mean}(a) is the plain inequality $|\mathsf J-e|\le V-e$ for the common mean energy $e$ of one positive form, and gives nothing new: the empty components on the two sides coincide. The gain comes from envelopes whose mean energies $e_{\rm L},e_{\rm R}$ exceed the mean energy $Y_\nu$ of the law itself. Only single-half energies occur, $X$ under $M_{\rm L}$ and $Y$ under $M_{\rm R}$, which is the order in which \eqref{eq:record:joint-gram} holds; the bracket with the envelopes exchanged is neither proved nor needed. \end{remark} \subsection{The signed average over intervals: cancellation except when intervals wrap} Recall from \cref{def:hyb:coupled} that $P_e$ averages over the whole index of the query $e$ and that $T_e$ is the coupled transition to the next interval with a square residue increment. The signed index form uses the signed combination $2P_e-T_e$ in place of $T_e$. Expanding the product over the $k$ queries \eqref{eq:record:expansion} isolates the term $2^kY_\nu$, in which every query is fully averaged. Every other term applies the actual coupled transition $T_e$ to a nonempty set of queries; such a term pairs two points in ordered intervals forced into a square class, so it is negligible by the kernel estimate---unless an interval wraps ($b_e=\Kint$, \cref{subsec:cp:index}), where the two intervals are no longer ordered and cancellation fails. The lemma bounds the wrapping terms by the quantity $W$. The signed combination is controlled by the same $2\times2$ domination as the ordinary coupling (\cref{cor:index-support-frame}), through \cref{lem:envelope-energy} below, whose proof does not depend on this lemma. \begin{lemma}[Expansion and wrap]\label{lem:record:wrap-expansion} Assume (CP0)--(CP4) and (CP8) of \cref{thm:comparison}, and put \[ W=Be^{S+A}\Bigl[\Bigl(1+\frac{R_I}{2\Kint^{1-2\theta/d}}\Bigr)^k-1\Bigr]. \] Then $|J_\nu-2^kY_\nu|\le(2^kW+o(1))Y$. The $o(1)$ consists of at most $3^kn_\nu$ cancellation remainders, with coefficients at most $2^k\mathfrak v_\nu e^{P+S}$, and of the energy errors and large-product remainders of the wrapping terms. \end{lemma} \begin{proof} By \eqref{eq:record:expansion}, $J_\nu-2^kY_\nu=\sum_{\mathcal S\ne\varnothing}(-1)^{|\mathcal S|} 2^{k-|\mathcal S|}I_{\nu,\mathcal S}$, where $I_{\nu,\mathcal S}$ carries the ordinary coupling on the queries of $\mathcal S\subseteq\mathcal E_k$ and the full average on the others. Split $I_{\nu,\mathcal S}=\sum_{\mathcal W\subseteq\mathcal S}I_{\nu,\mathcal S,\mathcal W}$ by the set $\mathcal W=\{e\in\mathcal S:b_e=\Kint\}$ of wrapping active queries; there are $3^k$ pairs $\mathcal W\subseteq\mathcal S$. \emph{The mass of $\nu$.} On a first-stage atom $\lambda_\Blk(1)=1+(\rho_\Blk-\mu_\Blk)(1)\le1+p_\Blk$, as the record differences of (CP2) have mass zero. The cut matrix of $\zeta^{\rm a}_{\Blk,t}$ is skew, so $\zeta^{\rm a}_{\Blk,t}(1)=0$, and the bracket of $\zeta^{\rm s}_{\Blk,t}$ in (CP4) at the all-ones vector gives $|\zeta^{\rm s}_{\Blk,t}(1)|\le\tilde\pi^{\rm s}_{\Blk,t}$. As $q_\Blk^{2a}\ge1$, $0<\nu(1)\le\prod_\Blk(1+p_\Blk+s_\Blk)\le e^{P+S}$. Hence, every factor $|\nu|_\Blk/\nu_\Blk(1)$ of (CP4) being at least one, $\prod_{\Blk\in\mathcal A_N}|\nu|_\Blk\le\mathfrak v_\nu\,\nu(1)\le \mathfrak v_\nu e^{P+S}$. \emph{Nonwrapping terms.} If $\mathcal W\ne\mathcal S$, pick $e\in\mathcal S\setminus\mathcal W$. Then $b_e\le\Kint-1$, the inputs $g^{I_{b_e},\Mzero,s_e}$ at $u_e$ and $g^{I_{b_e+1},\Mzero,s_e+r_e}$ at $v_e$ lie on adjacent ordered intervals, and $r_e$ is a nonvanishing square class modulo $\Mzero$, by (CP0)(d) and \cref{lem:imp:padic-envelope}. Expand every $\nu_\Blk$ into its components: $\nu$ becomes a sum of at most $n_\nu$ product components $\bigotimes_\Blk c_{\Blk,i_\Blk}\nu_{\Blk,i_\Blk}$. By (CP4)(a) the normalized factors $\bar\nu_{\Blk,i_\Blk}$ of each product component accept every query, have uniform one-slot marginals and satisfy (R4) and (R5) of \cref{hyp:record:reference}; their product is a probability measure of the form required in \cref{lem:record:density-can}, and these are the hypotheses of that lemma for $(u_e,v_e)$; the other slots carry inputs of \cref{def:record:functional}(f). At fixed indices each product component contributes $\prod_\Blk c_{\Blk,i_\Blk}\nu_{\Blk,i_\Blk}(1)$ times an integral bounded in that lemma, uniformly in the indices, so the bound persists after integration against their conditional law. Summing the absolute values of the coefficients over the product components gives $\prod_{\Blk\in\mathcal A_N}|\nu|_\Blk$. So $I_{\nu,\mathcal S,\mathcal W}$, with its expansion coefficient, is a sum of at most $n_\nu$ cancellation remainders whose coefficients add up to at most $2^k\prod_\Blk|\nu|_\Blk\le2^k\mathfrak v_\nu e^{P+S}$. No other step of this proof uses the components: the wrapping terms below are bounded through the brackets of (CP3) and (CP4), which hold for the signed $\nu_\Blk$, and not through the variation of $\nu$. \emph{Wrapping terms.} Let $\mathcal W=\mathcal S$ and $j=|\mathcal S|$. All $j$ intervals wrap with probability $\Kint^{-j}$. Given this, the averages $P_e$ ($e\notin\mathcal S$) replace those inputs by $F_A$ on both sides, and the term is $\Kint^{-j}\E_s\ip{X'(s)}{\Gamma(T'Y')(s)}$: $X'(s)$ carries $g^{I_\Kint,\Mzero,s_e}$ at $u_e$ and $Y'(s)$ carries $g^{I_1,\Mzero,s_e}$ at $\iota(v_e)$ ($e\in\mathcal S$), both carry $F_A$ elsewhere, $s$ is uniform, $\Gamma=C_\iota(\nu)$, and $T'$ is the residue part of the coupling on $\mathcal S$, a tensor product of doubly stochastic kernels with the norms given by the conductor tails of (CP0)(d) on exact-conductor spaces. On every atom the brackets of (CP3) and (CP4) add up to \[ \begin{pmatrix}M_\Blk&\nu_\Blk\\ \nu_\Blk^*&M_\Blk\end{pmatrix} \succeq_\iota0,\qquad M_\Blk=\Nbr_\Blk+\sum_t\bigl(\tilde\pi^{\rm s}_{\Blk,t}D^{\rm s}_{\Blk,t} +\tilde\pi^{\rm a}_{\Blk,t}D^{\rm a}_{\Blk,t}\bigr), \] and these tensorize (\cref{lem:record:block-gram}). As in the proof of \cref{lem:hyb:coupling}, $T'$ satisfies the hypotheses of \cref{lem:record:common-mean}, and part (b) bounds the term by $\Kint^{-j}(V'_{\rm L}V'_{\rm R})^{1/2}$, with $V'_{\rm L},V'_{\rm R}$ the single-half random-inclusion energies of $X'$ and $Y'$ under $\bigotimes_\Blk M_\Blk$. Here $M_\Blk-\Nbr_\Blk$ is a nonnegative combination of the admissible positive reserved-diagonal laws $D^\epsilon_{\Blk,t}$, of total price $S+A$, so \cref{lem:envelope-energy}, with $T_Q=S+A$ and the fixed intervals $I_\Kint$, $I_1$ ($\kappa_e=\Kint$, \cref{rem:wrap-coarse}), gives $V'_{\rm L},V'_{\rm R}\le(Be^{S+A}(\Kint^{2\theta/d}R_I)^j+o(1))Y$. Hence $|I_{\nu,\mathcal S,\mathcal S}|\le(Be^{S+A}(R_I\Kint^{2\theta/d-1})^j+o(1))Y$. \emph{Summation.} Summing $2^{k-j}$ times this over the $\binom kj$ sets of size $j$, \[ \sum_{j=1}^k\binom kj2^{k-j}Be^{S+A}\bigl(R_I\Kint^{2\theta/d-1}\bigr)^j =Be^{S+A}\bigl[(2+R_I\Kint^{2\theta/d-1})^k-2^k\bigr]=2^kW .\qedhere \] \end{proof} \begin{remark}[The wrap uses the coarse interval factor] \label{rem:wrap-coarse} In the wrapping terms the intervals are fixed, so each changed index slot has the coarse factor $\kappa_v=\Kint$ of \cref{def:record:structured-energy} ($\alpha_I\le\Kint\alpha$), which \cref{prop:record:density-structured} charges as $\Kint^{\theta/d}$. An active query changes two slots of each single-half energy, so the wrap pays $\Kint^{2\theta/d}$ per active query; at $d=72$, $\theta=1$ the ratio per query is $R_I/\Kint^{35/36}$, as in \cref{thm:comparison}. The finer factor $(\bar\alpha_v/\alpha)^{\theta/d}$ of the main price is not used: it may not be multiplied into the additive error of \cref{prop:record:density-structured}. \end{remark} \subsection{Energies of the dominating law, and \texorpdfstring{$Y_\lambda\ge(1-L_0-o(1))Y$}{Y\_lambda >= (1-L\_0-o(1))Y}} Neither the comparison law nor the bracket measure need be reflection positive along a sorting sequence, as the structured-energy estimate requires of the outside law (for the bracket, (CP3) gives positivity at $\iota$ only). Their energies are bounded by expanding them into admissible positive laws, whose energies \cref{prop:record:density-structured} bounds by their prices, and into record differences grouped in tags; at the cut of a tag all its differences are applied sharply together (\cref{lem:record:folded-energy}(d$'$)), and the folded-energy lemma bounds them by the geometric mean of two folded energies. This is done once (\cref{lem:sharp-first}); its consequences are the first comparison, the factor $B$ under the bracket, and the order relations that Part~V uses throughout. \paragraph{Energies of selected laws.} Fix structured slot data: divisors $D_{0,v}$ of $\Mzero$, lengths $M_v\in\{\Lsc,N\}$ and a law $\mathbf P$ of index vectors $\omega=(I_v,s_v)_{v\in V}$ independent of the labels, as in \cref{def:record:structured-energy}(c), with inputs $g^\omega_v=g^{I_v,D_{0,v},s_v}$. For a finite set $X$ of atoms let $\Pi_X$ be the coarse price of these data with selected set $X$; for unchanged inputs ($F_A$ at every slot) $\Pi_X=C_X$. An \emph{outside law} is one of the products $\mu$, $\Nbrz$, $\Nbr$ (with $\Nbrz$ as in \cref{def:cp3}); write $O_{-X}=\bigotimes_{\Blk\notin X}O_\Blk$. For a finite signed measure $\kappa$ on $X_X^V$ put \[ \mathfrak E_O[\kappa]=\E_{\omega\sim\mathbf P}\int\Lambda_{O_{-X}} \bigl((g^\omega_v(z_v,\cdot))_{v\in V}\bigr)\,d\kappa(z),\qquad \mathfrak E=\mathfrak E_\mu, \] and, for unchanged inputs, $Y^O[\kappa]=Y_{\kappa\otimes O_{-X}}$, $Y[\kappa]=Y^\mu[\kappa]$. At any cut an energy is the value of the cut form of the measure at the half-function carrying $F_A$ at every slot of the plus half, whose reflection is the same half-function \eqref{eq:cc:bilinear}. Thus $Y[\bigotimes_{\Blk\in X}\mu_\Blk]=Y$, and for admissible positive $\kappa$ with $q_X\le N^\tau$, $\mathfrak E[\kappa]$ is a structured energy. \begin{lemma}[Tagged sharp-first expansion]\label{lem:sharp-first} Assume (CP1) of \cref{thm:comparison}. Let $F$ be a finite set of atoms and $\mathfrak T$ a finite set of tags with cuts $c_j\in\mathfrak F$, and for $\Blk\in F$ let $\rho_\Blk$ and $\delta_{\Blk,i}$ ($i$ in a finite set) be finite signed measures on $X_\Blk^V$ such that: \begin{enumerate}[label=(\alph*)] \item $\rho_\Blk-\mu_\Blk=\sum_hc_h\rho_h$ is a finite real combination of admissible positive measures, of \emph{variation price} $p_\Blk=\sum_h|c_h|\rho_h(1)q_\Blk^{2a}$; \item $\delta_{\Blk,i}=\kappa'_{\Blk,i}-\kappa_{\Blk,i}$ with admissible positive measures of equal mass $w_{\Blk,i}$; it carries a tag $j(\Blk,i)\in\mathfrak T$ and has a sharp bound $\tilde d_{\Blk,i}$ relative to $\kappa_{\Blk,i}$ at the cut $c_{j(\Blk,i)}$ of its tag, in the sense of \cref{def:price}(b): for a probability law $\pi$ of shared labels, $\kappa_{\Blk,i}=w_{\Blk,i}\int\kappa_s\,\pi(ds)$ and $\delta_{\Blk,i}=w_{\Blk,i}\int K_s\,\pi(ds)$, each $K_s$ satisfying \eqref{eq:record:sharp} at $c_{j(\Blk,i)}$ relative to the half marginals of $\kappa_s$ with the constant $\tilde d_{\Blk,i}$. \end{enumerate} Let $d_{\Blk,i}=\tilde d_{\Blk,i}w_{\Blk,i}q_\Blk^{2a}$ be the sharp price of $\delta_{\Blk,i}$ and $v_{\Blk,i}=2w_{\Blk,i}q_\Blk^{2a}$ the price of its two positive parts (as in (CP2)(b)), $P=\sum_\Blk p_\Blk$, and let $d_j$ and $v_j$ be the sums of the $d_{\Blk,i}$ and of the $v_{\Blk,i}$ over the differences of tag $j$. Assume that these prices satisfy the summability condition of (CP8)(c), as they do in the applications below; in particular $P$ and the $d_j$, $v_j$ are bounded independently of the scale. Let $X$ be a fixed finite set of atoms disjoint from $F$ and $\kappa$ an admissible positive measure on $X_X^V$. Then, for structured slot data and with the selected set $X\cup F$, \[ \Bigl|\mathfrak E\Bigl[\kappa\otimes\bigotimes_{\Blk\in F} \Bigl(\rho_\Blk+\sum_i\delta_{\Blk,i}\Bigr)\Bigr] -\mathfrak E\Bigl[\kappa\otimes\bigotimes_{\Blk\in F}\rho_\Blk\Bigr]\Bigr| \le\bigl(e^P\tagser(d,v)+o(1)\bigr)\|\kappa\|\,\Pi_XY , \] with $\tagser$ the series of (CP2). The $o(1)$ consists of energy errors and one large-product remainder. \end{lemma} \begin{proof} We expand the product over $F$ and bound each nonempty choice of differences at the cut of its tag; summing over count vectors gives the series $\tagser(d,v)$. A term of the difference chooses a nonempty set $S\subseteq F$ of atoms and one difference $\delta_{\Blk,i_\Blk}$ at each $\Blk\in S$, and carries $\rho_\Blk$ at the atoms of $F\setminus S$; at most one difference of an atom enters a term. Its \emph{count vector} is $\boldsymbol k\in\Z_{\ge0}^{\mathfrak T}\setminus\{0\}$, $k_j=|\{\Blk\in S:j(\Blk,i_\Blk)=j\}|$. The terms with count vector $\boldsymbol k$ form the \emph{category} of $\boldsymbol k$. Fix $\boldsymbol k$ and a tag $j$ with $k_j\ge1$; we bound the sum of the absolute values of the terms of the category, using the cut $c_j$. In a term of the category let $S_j\subseteq S$ be the $k_j$ atoms whose difference has tag $j$. Expand the difference at every atom of $S\setminus S_j$ into its two given positive parts (not into its Jordan parts, whose marginals need not be uniform), and every $\rho_\Blk$, $\Blk\in F\setminus S$, as $\mu_\Blk+\sum_hc_h\rho_h$. The term becomes a signed sum of energies $T'$ in which the atoms of $S_j$ carry their tag-$j$ differences, a set $X'\subseteq F\setminus S_j$ carries admissible positive measures, $X$ carries $\kappa$, and every other atom carries $\mu_\Blk$. In $T'$ apply \cref{lem:record:folded-energy} at $c_j$ with the selected set $E=X\cup X'\cup S_j$. The outside $\mu_\Blk$ are reflection positive at $c_j$ by (R2) at every cut of the family (CP1). Each $\delta_{\Blk,i_\Blk}$, $\Blk\in S_j$, is $w_{\Blk,i_\Blk}\int K_s\,\pi_\Blk(ds)$ with kernels that satisfy \eqref{eq:record:sharp} at the common cut $c_j$; by part (d$'$) of that lemma, under the product law of the shared labels, their tensor product over $S_j$ satisfies \eqref{eq:record:sharp} at $c_j$ relative to the product of the $\kappa_s$, with the constant $\prod_{\Blk\in S_j}\tilde d_{\Blk,i_\Blk}$. The normalized positive measures on $X\cup X'$ form a coupling $\pi''$ of its half marginals, so by part (d) the tensor product with $\pi''$ keeps this constant: positive couplings are contractions between their marginal spaces, and no positivity of these factors at $c_j$ is used. By parts (a), (c), $|T'|$ is at most $\prod_{\Blk\in S_j}\tilde d_{\Blk,i_\Blk}w_{\Blk,i_\Blk}$ times the masses of the positive factors times the geometric mean of two folded energies $\mathfrak E_\pm$; by (b) these are energies of admissible positive measures, since a fold only copies an existing slot, and by (e) their coarse prices multiply to $\Pi(T')^2$, $\Pi(T')=\Pi_X\prod_{\Blk\in X'\cup S_j}q_\Blk^{2a}$. If $q_E\le N^\tau$, \cref{prop:record:density-structured}, applied once to each folded energy with the union $E$ of the selected moduli, gives \[ |T'|\le(1+o(1))\prod_{\Blk\in S_j}d_{\Blk,i_\Blk}\prod_{\Blk\in X'} \bigl(\text{price of the positive factor at }\Blk\bigr)\,\|\kappa\|\,\Pi_XY : \] the geometric mean retains $\Pi(T')$, not $\Pi(T')^2$, no atom is charged twice, and $1+o(1)$ is not raised to the number of selected atoms. The terms with $q_E>N^\tau$ have the form $a_E(I^+_EI^-_E)^{1/2}$ of \cref{lem:record:density-lp}. Summing over the energies $T'$ of one term: at an atom of $S\setminus S_j$ the two positive parts have total price $v_{\Blk,i_\Blk}$, and at an atom of $F\setminus S$ the factor is $\mu_\Blk$ (weight one) or a positive record of $\rho_\Blk-\mu_\Blk$ (total weight $p_\Blk$). Summing then over the terms of the category, and dropping the requirement that the atoms be distinct, which only adds nonnegative terms, the category is at most \[ (1+o(1))\,\frac{d_j^{k_j}\prod_{j'\ne j}v_{j'}^{k_{j'}}} {\prod_{j'\in\mathfrak T}k_{j'}!}\,\prod_{\Blk\in F}(1+p_\Blk)\, \|\kappa\|\,\Pi_XY , \] because the sum, over the sets of $k_{j'}$ differences of tag $j'$ at distinct atoms, of the product of their prices is at most the $k_{j'}$-th power of the total price of the tag divided by $k_{j'}!$. This holds for every tag $j$ with $k_j\ge1$, and we use the tag that gives the smallest bound. The minimum is taken after the whole category has been bounded with each tag, not inside the sum over its terms, so it needs no relation between the ratios $d_{\Blk,i}/v_{\Blk,i}$ of the individual differences; the two bounds refer to the same terms, and their intermediate folded couplings need not coincide. The categories partition the terms. Summing over $\boldsymbol k\ne0$ and using $\prod_\Blk(1+p_\Blk)\le e^P$ gives the main term $e^P\tagser(d,v)\|\kappa\|\Pi_XY$, the tag totals over $F$ being at most the totals of the statement and $\tagser$ being nondecreasing. The terms with $q_E>N^\tau$ of all categories form one large-product remainder: such a term is determined by the role of each atom of $E\setminus X$ (a difference applied sharply, a positive part of a difference, or a positive record of $\rho_\Blk-\mu_\Blk$), so for each $E$ their coefficients add up to at most $\|\kappa\|\,\Pi_X$ times the product over $E\setminus X$ of $p_\Blk+v_\Blk+d_\Blk$, with $v_\Blk=\sum_iv_{\Blk,i}$, $d_\Blk=\sum_id_{\Blk,i}$. \end{proof} \begin{corollary}[Two tags]\label{cor:two-cut-series} Let $\mathfrak T=\{0,1\}$ and $d_0=d_1\le v_0=v_1$, and write $d$ and $v$ for the common values (here $d$ is a tag total, not the number of slots) and $\tagser(d,v)$ for the series of (CP2) at these totals. Then \[ \tagser(d,v)=\sum_{k_0+k_1>0}\frac{d^{\max(k_0,k_1)}v^{\min(k_0,k_1)}} {k_0!\,k_1!}. \] For every integer $n\ge1$ with $dN^\tau$ are retained in the aggregate large-product remainder described above. On a first-stage atom $\Blk\notin X$ write $\Nbr_\Blk=\Nbr_{0,\Blk}+\delta_{E,\Blk}$ and $\Nbr_{0,\Blk}=\mu_\Blk+(\Nbr_{0,\Blk}-\mu_\Blk)$, the second summand being an admissible positive measure of price $u_\Blk$ by (CP3) and (CP8). Expanding the latter, $\mathfrak E_{\Nbrz}[\kappa]$ is the sum over the sets $X'$ of first-stage atoms outside $X$ of the energies with selected measures $\kappa\otimes\bigotimes_{\Blk\in X'}(\Nbr_{0,\Blk}-\mu_\Blk)$, each at most $(1+o(1))\|\kappa\|\,\Pi_X\prod_{X'}u_\Blk\,Y$; the sum is at most $(1+o(1))\prod_\Blk(1+u_\Blk)\|\kappa\|\,\Pi_XY\le(1+o(1))e^{U_0}\|\kappa\|\,\Pi_XY$. The difference is \cref{lem:sharp-first} with $F$ the first-stage atoms outside $X$, $\rho_\Blk=\Nbr_{0,\Blk}$ (variation price $u_\Blk$) and the tagged record differences of (CP2)(b): it is at most $(e^{U_0}\tagser(d,v)+o(1))\|\kappa\|\,\Pi_XY=(R_{\rm err}+o(1))\|\kappa\|\, \Pi_XY$, the tag totals over the first-stage atoms outside $X$ being at most those of (CP2) and $\tagser$ being nondecreasing. For the last assertion, the two factors of a Cauchy--Schwarz step have coarse prices whose product is the square of the original price (\cref{lem:record:folded-energy}(e)). \end{proof} The next lemma collects the order, contraction and interpolation estimates for energies that Part~V applies repeatedly: its parts (E1)--(E3) are the basic comparisons, and (P1)--(P5), (P3$'$) are the product estimates used when a bound proved in a fixed chart is transported to actual marginals (restoration), when centred norms are interpolated, and when class bounds are formed, in the places named in Part~V. \begin{lemma}[Energy toolkit: order, contraction and interpolation estimates]\label{lem:energy-toolkit} Assume (CP1)--(CP3) and (CP8) of \cref{thm:comparison}. Let $X$ be a finite set of atoms and $\kappa,\kappa'$ finite signed measures on $X_X^V$. In (E2), (P1)--(P3) and (P3$'$), $\vartheta$ is a cut of the family and $O=\mu$, or $\vartheta=\iota$ and $O$ is any outside law. \begin{enumerate}[label=(E\arabic*)] \item\label{it:record:E1} If $\kappa$ is positive and admissible, then $|Y[\kappa]|\le(1+o(1))\|\kappa\|C_XY$, $|Y^{\Nbrz}[\kappa]|\le(e^{U_0}+o(1))\|\kappa\|C_XY$, $|Y^{\Nbr}[\kappa]|\le(B+o(1))\|\kappa\|C_XY$ and $|Y^{\Nbr}[\kappa]-Y^{\Nbrz}[\kappa]|\le(R_{\rm err}+o(1))\|\kappa\|C_XY$. \item\label{it:record:E2} If $\kappa\succeq_\vartheta\kappa'$, then $Y^O[\kappa]\ge Y^O[\kappa']$; more generally, at any cut $\vartheta$, $\kappa\succeq_\vartheta\kappa'$ implies $Y_{\kappa\otimes O'}\ge Y_{\kappa'\otimes O'}$ for every finite signed measure $O'$ on the labels of the atoms outside $X$ with $O'\succeq_\vartheta0$. If $\kappa\succeq_\iota0$, then $Y[\kappa]\le Y^{\Nbrz}[\kappa]$. \item\label{it:record:E3} A positive measure fixed samplewise by the reflection of $\vartheta$ (\emph{diagonal at $\vartheta$}) has a nonnegative diagonal cut matrix at $\vartheta$, so it is $\succeq_\vartheta0$. \end{enumerate} For a positive measure $m$ on the plus-half labels at $\vartheta$ let $\operatorname{Diag}_\vartheta(m)$ be its diagonal copy of \cref{lem:commoncut}(i) (the plus half has law $m$, the minus half is its reflection) and $J_\vartheta(m)=(m\otimes m)/m(1)$ the measure with independent halves of laws proportional to $m$. \begin{enumerate}[label=(P\arabic*)] \item\label{it:record:P1} \emph{Contraction.} If $\pi$ is a positive measure on $X_X^V$ with half marginals $m_\pm$ at $\vartheta$, then $|Y^O[\pi]|\le Y^O[\operatorname{Diag}_\vartheta(m_+)]^{1/2} Y^O[\operatorname{Diag}_\vartheta(m_-)]^{1/2}$, where $\operatorname{Diag}_\vartheta(m_-)$ is the diagonal measure whose minus half has law $m_-$. \item\label{it:record:P2} \emph{Density domination.} If $m\le Mm'$ for positive measures on the plus-half labels, then $Y^O[\operatorname{Diag}_\vartheta(m)]\le MY^O[\operatorname{Diag}_\vartheta(m')]$. \item\label{it:record:P3} \emph{Centred interpolation.} Let $\pi$ be a positive measure symmetric at $\vartheta$ with half marginal $m$ and Markov operator $T$ on $L^2(m)$. If $\|T-\Jproj\|\le\kappa_0\le1$, then $\pi\preceq_\vartheta(1-\kappa_0)J_\vartheta(m) +\kappa_0\operatorname{Diag}_\vartheta(m)$, hence $Y^O[\pi]\le(1-\kappa_0) Y^O[J_\vartheta(m)]+\kappa_0Y^O[\operatorname{Diag}_\vartheta(m)]$. The case $\kappa_0=1$ holds for every such $\pi$. \item[(P3$'$)]\setprimedlabel{(P3$'$)}\label{it:record:P3b} \emph{Product centred interpolation.} Let $\pi$ be as in (P3), on the labels of $X$, with half marginal $m$ and constant $\kappa_0\le1$, and let $\pi'$ be a positive measure on the labels of a finite set $Z$ of atoms disjoint from $X$, symmetric at $\vartheta$, with half marginal $m'$. Then \[ \pi\otimes\pi'\preceq_\vartheta(1-\kappa_0)\,J_\vartheta(m)\otimes \operatorname{Diag}_\vartheta(m')+\kappa_0\operatorname{Diag}_\vartheta(m\otimes m'), \] hence $Y^O[\pi\otimes\pi']\le(1-\kappa_0)Y^O[J_\vartheta(m)\otimes \operatorname{Diag}_\vartheta(m')]+\kappa_0Y^O[\operatorname{Diag}_\vartheta(m\otimes m')]$. No order is tensored with an indefinite factor: $\pi'$ enters only through its Markov operator, a self-adjoint contraction. \item\label{it:record:P4} \emph{Products.} If $\pi_\Blk$ $(\Blk\in X)$ are as in (P3) with half marginals $m_\Blk$ and constants $\kappa_\Blk$, then $\bigotimes_\Blk\pi_\Blk$ is as in (P3) with half marginal $\bigotimes_\Blk m_\Blk$ and constant $\max_\Blk\kappa_\Blk$. \item\label{it:record:P5} \emph{$\pm$ tensorization.} If $\zeta$ is a signed measure on $X_X^V$ with $\kappa\pm\zeta\succeq_\iota0$, then $|Y_{\zeta\otimes\lambda_{-X}}|\le Y^{\Nbr}[\kappa]$. If $\bigl(\begin{smallmatrix}\kappa&\zeta\\ \zeta^*&\kappa'\end{smallmatrix} \bigr)\succeq_\iota0$, then $|Y_{\zeta\otimes\lambda_{-X}}|\le Y^{\Nbr}[\kappa]^{1/2}Y^{\Nbr}[\kappa']^{1/2}$. If the cut matrix of $\zeta$ at $\iota$ is skew, then $Y_{\zeta\otimes\lambda_{-X}}=0$. \end{enumerate} \end{lemma} \begin{proof} \ref{it:record:E1} is \cref{lem:bracket-energy} for unchanged inputs. \ref{it:record:E2}: for $O'$ as stated, the cut matrix of $(\kappa-\kappa')\otimes O'$ at $\vartheta$ is $C_\vartheta(\kappa-\kappa')\otimes C_\vartheta(O')$ \eqref{eq:cc:kron}, a Kronecker product of symmetric positive semidefinite matrices; evaluate at the half-function carrying $F_A$ \eqref{eq:cc:bilinear}. The outside laws are such measures: $\mu_{-X}\succeq_\vartheta0$ at every cut of the family by (R2), as tensor products of reflection positive measures are reflection positive (\cref{def:rp}); $\Nbr_{-X}\succeq_\iota0$ because each $\Nbr_\Blk$ is a diagonal block of the bracket of (CP3); and $\Nbr_{0,-X}\succeq_\iota0$ because $\Nbr_{0,\Blk}=\mu_\Blk+(\Nbr_{0,\Blk}-\mu_\Blk)$, with $\mu_\Blk\succeq_\iota0$ and the second summand positive and reserved diagonal, hence $\succeq_\iota0$ by (E3). For the last claim, $0\preceq_\iota\mu_\Blk\preceq_\iota \Nbr_{0,\Blk}$, so $\mu_{-X}\preceq_\iota\Nbr_{0,-X}$ (\cref{lem:record:block-gram}(d)), and $C_\iota(\kappa)\otimes(C_\iota(\Nbr_{0,-X})-C_\iota(\mu_{-X}))\succeq0$. \ref{it:record:E3} is \cref{lem:commoncut}(i). \ref{it:record:P1} Let $D_\pm$ be the diagonal cut matrices of $\operatorname{Diag}_\vartheta(m_\pm)$, the minus half read on the plus half through the reflection. For real $f,g$ on the plus-half labels, $\ip f{D_+f}+2\ip f{C_\vartheta(\pi)g}+\ip g{D_-g}=\int(f(z_+)+g(\tilde z_-))^2 \,d\pi\ge0$, with $\tilde z_-$ the reflected minus half, so $\bigl(\begin{smallmatrix}D_+&C_\vartheta(\pi)\\ C_\vartheta(\pi)^{\mathsf T}&D_-\end{smallmatrix}\bigr)\succeq0$. Tensorize with $\bigl(\begin{smallmatrix}1&1\\1&1\end{smallmatrix}\bigr)\otimes C_\vartheta(O_{-X})$ and apply the block-Gram inequality (\cref{lem:record:block-gram}) at the half-function carrying $F_A$; for $O=\mu$ this is \cref{lem:record:folded-energy}(a) with $d=1$. \ref{it:record:P2}: $\operatorname{Diag}_\vartheta(Mm'-m)$ is positive and diagonal at $\vartheta$; apply (E3), (E2). \ref{it:record:P3} Relative to $m$ the cut matrices of $\pi$, $J_\vartheta(m)$ and $\operatorname{Diag}_\vartheta(m)$ are $D_mT$, $D_m\Jproj$ and $D_m$ ($D_m$ the diagonal matrix of $m$), so the cut order between measures of half marginal $m$ is the Loewner order of their operators on $L^2(m)$. $T$ is self-adjoint and fixes the constants, so $T-\Jproj=(I-\Jproj)(T-\Jproj)(I-\Jproj)\preceq\kappa_0(I-\Jproj)$, that is, $T\preceq(1-\kappa_0)\Jproj+\kappa_0I$; apply (E2). The Markov operator of a positive coupling is a contraction on $L^2(m)$ (Jensen), so $\|T-\Jproj\|\le1$ always. \ref{it:record:P3b} Relative to $m\otimes m'$ the cut matrices of $\pi\otimes\pi'$, $J_\vartheta(m)\otimes\operatorname{Diag}_\vartheta(m')$ and $\operatorname{Diag}_\vartheta(m\otimes m')$ are $D(T\otimes T')$, $D(\Jproj\otimes I)$ and $D$, with $D$ the diagonal matrix of $m\otimes m'$ and $T'$ the Markov operator of $\pi'$ on $L^2(m')$, which is self-adjoint, because $\pi'$ is symmetric, and a contraction. The operator $T\otimes T'$ maps $\operatorname{ran}\Jproj\otimes L^2(m')$ and its orthogonal complement $L^2_0(m)\otimes L^2(m')$ into themselves. On the first it is $I\otimes T'\preceq I$; on the second it is $(T-\Jproj)\otimes T'$, self-adjoint of norm at most $\kappa_0$, hence $\preceq\kappa_0I$. So $T\otimes T'\preceq\Jproj\otimes I+\kappa_0(I-\Jproj)\otimes I =(1-\kappa_0)\Jproj\otimes I+\kappa_0I$, which is the order claimed; apply (E2). \ref{it:record:P4}: the Markov operator of the product is $\bigotimes_\Blk T_\Blk$, self-adjoint, and $\|\bigotimes_\Blk T_\Blk-\Jproj\|=\max_\Blk\|T_\Blk-\Jproj\|$ (\cref{lem:sector}(c)). \ref{it:record:P5} By (CP3), $\Nbr_\Blk\pm\lambda_\Blk\succeq_\iota0$ for every atom (off the first-stage atoms these are $2\mu_\Blk$ and $0$). With $\kappa\pm\zeta\succeq_\iota0$, \cref{lem:record:block-gram}(d) gives $\kappa\otimes\Nbr_{-X}\pm\zeta\otimes\lambda_{-X}\succeq_\iota0$, and evaluation at the half-function carrying $F_A$ gives the first claim. For the bracket form tensorize the bracket of $\zeta$ with those of (CP3) (\cref{lem:record:block-gram}(b)) and apply part (a) of that lemma. If $C_\iota(\zeta)$ is skew, so is $C_\iota(\zeta)\otimes C_\iota(\lambda_{-X})$, whose form vanishes at two equal arguments (\cref{rem:cut-symmetries}(a)). \end{proof} \subsection{Expanding \texorpdfstring{$\nu-\lambda$}{nu-lambda} over changed blocks: the bound as a power series in prices} The difference $Y_\nu-Y_\lambda$ at the reserved cut is expanded by choosing, at any set of atoms, which records were changed; each such choice is a \emph{selection}. A selection in no special class is bounded by $B$ times the product of the prices of its changed records. Selections in a class of (CP5) may have a smaller proved bound. Summing over all selections gives a power series in the prices; any series with nonnegative coefficients that dominates it coefficient by coefficient (a \emph{complete polynomial}, \cref{subsec:intro:glossary}) may be used in the closing. This subsection makes the expansion precise. \paragraph{Selections.} Recall from (CP4)(b), (c) (\cref{def:record:comparison-law}) the decomposition $\nu_\Blk-\lambda_\Blk=\sum_{t\in\mathcal T_\Blk}(\zeta^{\rm s}_{\Blk,t}+ \zeta^{\rm a}_{\Blk,t})$ over the changed records $t$ of $\Blk$, the brackets of $\zeta^\epsilon_{\Blk,t}$ with the norm envelopes $\tilde\pi^\epsilon_{\Blk,t}D^\epsilon_{\Blk,t}$, the prices $\pi^\epsilon_{\Blk,t}$ with totals $S$ and $A$, and the selections $\omega$ (a set $X$ of atoms with a record $t_\Blk$ and a type $\epsilon_\Blk$ at each, an even number of them skew) with their measures $\zeta_\omega$, monomials $\pi_\omega$ and terms $I_\omega=Y_{\zeta_\omega\otimes\lambda_{-X}}$. In formal variables $x=(x^\epsilon_{\Blk,t})$ for the prices and $y=(y_{\Blk,j})$ for the auxiliary prices of (CP5) let $S(x)=\sum x^{\rm s}_{\Blk,t}$, $A(x)=\sum x^{\rm a}_{\Blk,t}$ and $e^{S(x)}\cosh A(x)-1=\sum_{\boldsymbol n}c_{\boldsymbol n}x^{\boldsymbol n}$, the sum over the nonconstant monomials of even skew degree. Every $c_{\boldsymbol n}$ is positive (it is $1/\boldsymbol n!$), and a squarefree monomial has coefficient one; so has, in particular, the monomial $x^{\boldsymbol n(\omega)}$ of a selection, for which $\pi^{\boldsymbol n(\omega)}=\pi_\omega$. A selection determines its atoms, records and types, hence its monomial; selections of different patterns of types, also those without skew types, are different monomials, and (CP5) may be proved for every pattern with an even number of skew types. For a selection of a class $\mathcal C$ of (CP5) with a class cost let $c_\omega=c_{\mathcal C}$, and $c_\omega=B$ for a selection in no class; for these put $b_\omega=c_\omega x^{\boldsymbol n(\omega)}$. For a selection of a class with class bounds put $b_\omega=\phi_\omega$, a polynomial in $y$. A monomial in $x$ is the monomial of at most one selection, and a monomial of a class bound determines its selection (CP5); so $\sum_\omega b_\omega$, the sum over all selections of atoms of $\mathcal A$, is a power series in $(x,y)$ with nonnegative coefficients, each of whose coefficients is a finite sum of coefficients of the $b_\omega$. \begin{lemma}[Record expansion and complete polynomial] \label{lem:record:record-expansion} Assume (CP0)--(CP4) and (CP8) of \cref{thm:comparison}. \begin{enumerate}[label=(\roman*)] \item $Y_\nu-Y_\lambda=\sum_\omega I_\omega$, and $|I_\omega|\le(B+o(1))\pi_\omega Y$ for every fixed selection $\omega$. \item \emph{Complete polynomials.} Assume (CP5). Let $\Psi(x,y)$ be a power series with nonnegative coefficients such that $\Psi-\sum_\omega b_\omega$ has nonnegative coefficients. Then $|Y_\nu-Y_\lambda|\le(\Psi(\hat\pi,\hat y)+o(1))Y$ for all upper prices $\hat\pi\ge\pi$ and upper auxiliary prices $\hat y\ge y$ at which $\Psi$ converges. Such a $\Psi$ is a \emph{complete polynomial}. Without classes, $\Psi=B(e^{S(x)}\cosh A(x)-1)$, and this reads $|Y_\nu-Y_\lambda|\le(B(e^S\cosh A-1)+o(1))Y$; with $B'\ge B$ (for instance a certified upper bound for $B$) every $B$ may be replaced by $B'$. For classes with class costs, $\Psi=\sum_{\boldsymbol n}(B'-\hat g_{\boldsymbol n})c_{\boldsymbol n}x^{\boldsymbol n}$ is complete whenever $0\le\hat g_{\boldsymbol n}\le B'$ for every $\boldsymbol n$ and $\hat g_{\boldsymbol n(\omega)}\le B'-c_\omega$ for every selection $\omega$ (the $\hat g_{\boldsymbol n}$ are arbitrary in $[0,B']$ on the other monomials, which have a repeated atom). \item $\Psi$ is nondecreasing in each price variable and in each auxiliary variable. In particular an upper bound for the total of a nonempty set of variables may be distributed over them in proportion to their actual values when their total is positive, and arbitrarily as nonnegative upper prices when their total is zero, giving a sum exactly equal to the given bound. \item \emph{Completion.} Assume (CP5) with class costs, and let $B'\ge B$. Let $\mathcal D(x)=\sum_{\boldsymbol n}d_{\boldsymbol n}x^{\boldsymbol n}$ be a power series with nonnegative coefficients, convergent at $\hat\pi$, with $d_{\boldsymbol n}\le B'-c_\omega$ on the monomial of every selection and $d_{\boldsymbol n}\le B'c_{\boldsymbol n}$ on every other monomial ($c_{\boldsymbol n}=0$ if $x^{\boldsymbol n}$ does not occur). Then, with $\hat S=S(\hat\pi)$, $\hat A=A(\hat\pi)$, \[ |Y_\nu-Y_\lambda|\le\bigl(B'(e^{\hat S}\cosh\hat A-1)-\mathcal D(\hat\pi) +o(1)\bigr)Y . \] That is, $\Psi=B'(e^{S(x)}\cosh A(x)-1)-\mathcal D(x)$ is a complete polynomial in the sense of (ii). \item \emph{Degree-class replacement.} Divide the skew records into kinds $1,\dots,r$: for every kind $l$ a set $\mathcal R_l$ of pairs $(\Blk,t)$, $t\in\mathcal T_\Blk$, the sets being disjoint. Let $A_l(x)=\sum_{(\Blk,t)\in\mathcal R_l}x^{\rm a}_{\Blk,t}$, and let every $(\Blk,t)\in\mathcal R_l$ carry auxiliary prices $y^{\rm arm}_{\Blk,t},y^{\rm lead}_{\Blk,t},y^{\rm rem}_{\Blk,t}\ge0$ (raw-arm, leading and remainder), attached to $(t,{\rm a})$, with totals $A^{\rm arm}_l$, $A^{\rm lead}_l$, $A^{\rm rem}_l$ over $\mathcal R_l$. For $\boldsymbol n\in\Z_{\ge0}^r$ with $|\boldsymbol n|\ge2$ even let $\mathcal C_{\boldsymbol n}$ be the class of the selections consisting of $n_l$ skew records of kind $l$ for every $l$ and of no other record, and suppose that $\mathcal C_{\boldsymbol n}$ satisfies (CP5) with \[ \phi_\omega=C_{\boldsymbol n}\prod_{\Blk\in X}y^{\rm arm}_{\Blk,t_\Blk} +B'\Bigl(\prod_{\Blk\in X}\bigl(y^{\rm lead}_{\Blk,t_\Blk} +y^{\rm rem}_{\Blk,t_\Blk}\bigr)-\prod_{\Blk\in X}y^{\rm lead}_{\Blk,t_\Blk}\Bigr) \] for a number $C_{\boldsymbol n}\ge0$, where $X=X(\omega)$. Let $\Psi_0$ be a complete polynomial for the other classes, the selections of $\mathcal C_{\boldsymbol n}$ being in no class, whose coefficients on the monomials of degree $n_l$ in the skew variables of kind $l$ for every $l$ and of degree zero in all other variables are those of $B'(e^{S(x)}\cosh A(x)-1)$. Then, with $\boldsymbol n!=\prod_ln_l!$, \[ \Psi=\Psi_0-\frac1{\boldsymbol n!}\Bigl[B'\prod_lA_l^{n_l} -C_{\boldsymbol n}\prod_l\bigl(A^{\rm arm}_l\bigr)^{n_l} -B'\Bigl(\prod_l\bigl(A^{\rm lead}_l+A^{\rm rem}_l\bigr)^{n_l} -\prod_l\bigl(A^{\rm lead}_l\bigr)^{n_l}\Bigr)\Bigr], \] read as a power series in the variables of the individual records, is a complete polynomial for all the classes. For a set of such degree vectors the replacements add. \emph{Credits:} if moreover the selections $\omega$ of $\mathcal C_{\boldsymbol n}$ satisfy (CP5) with the smaller class bounds $\phi_\omega-\gamma_\omega$, where the credits $\gamma_\omega$ are polynomials with nonnegative coefficients (for instance variance credits on the raw-arm monomials), then $\Psi-\Gamma$ is a complete polynomial for every power series $\Gamma$ with nonnegative coefficients whose coefficient is at most that of $\gamma_\omega$ on every monomial of a selection $\omega$ of $\mathcal C_{\boldsymbol n}$ and at most that of $\Psi-\sum_\omega b_\omega$ on every other monomial, as in (iv). \end{enumerate} The $o(1)$ consists of energy errors and large-product remainders. \end{lemma} In (ii) the bounds of (CP5) hold robustly and uniformly in the class ((CP8)(b)); this is where the bounded arity $n_{\max}$ enters, since the bounds of the classes then come from finitely many types of operator reductions. No argument uses a particular arity. In Part~V every selection of the variance, background and late-pool credits and of the envelope classes has at most six atoms, and so has every selection of the mean savings of (CP7) (\cref{prop:background-variance,lem:pool-coupons}). The replacement (v) applies to coarser kinds as well: if $C_{\boldsymbol n}$ depends only on the sums of the $n_l$ over groups of kinds, then by the multinomial expansion the replacements of the degree vectors with given group sums add up to the replacement for the merged kinds, whose totals are the sums of the totals. In Part~V the kinds are the fold records and the two matching records $E_0$, $E_1$: the general classes, with $n$ fold and $m$ matching records, are replaced with the merged kind of the matching records, and the matching pairs with $E_0$ and $E_1$ separate, the aligned pairs (two records of one kind) and the crossed pairs (one of each) each having the total $A_E^2/4$, the two matching records having equal totals (\cref{cor:envelope-costs,def:closing-quantities}). \begin{proof} (i) Expand $\nu=\bigotimes_\Blk(\lambda_\Blk+\sum_t(\zeta^{\rm s}_{\Blk,t}+\zeta^{\rm a}_{\Blk,t}))$. A term with an odd number of skew factors has a skew cut matrix at $\iota$, because $\lambda_\Blk$ is symmetric there by (CP3), and vanishes by \ref{it:record:P5}. The remaining terms are $Y_\lambda$ and the $I_\omega$. For a selection, the tensor product of the brackets of its factors and \ref{it:record:P5} give $|I_\omega|\le\prod_{\Blk\in X} \tilde\pi^{\epsilon_\Blk}_{\Blk,t_\Blk}\,Y^{\Nbr}[\bigotimes_{\Blk\in X} D^{\epsilon_\Blk}_{\Blk,t_\Blk}]\le(B+o(1))\pi_\omega Y$ by \ref{it:record:E1}, the laws $D^\epsilon_{\Blk,t}$ being admissible and normalized. (ii) Fully expand the bracket outside each selection as in the proof of \cref{lem:bracket-energy}. For selections in no class, apply the uniform structured-energy bound only to the resulting terms whose full union $E$ satisfies $q_E\le N^\tau$; the other terms, summed over the selections and the outside expansion together, are one large-product remainder. Their coefficients are bounded by products of the sums of the local prices in (CP8)(c), so \cref{lem:record:density-lp} makes their total $o(1)Y$. The small terms have one uniform relative energy error. Combine these bounds with the class sums of (CP5), which are uniform by (CP8)(b). Thus, after adding this aggregate remainder, $|Y_\nu-Y_\lambda|\le\sum_\omega|I_\omega|\le\sum_\omega\bigl(b_\omega(\pi,y) +o(1)\pi_\omega\bigr)Y+o(1)Y$, with $b_\omega(\pi,y)=c_\omega\pi_\omega$ off the classes with class bounds and $b_\omega(\pi,y)=\phi_\omega(y)$ on them, the bounds of (CP5) being uniform in the class ((CP8)(b)). The arguments $(\pi,y)$ and $(\hat\pi,\hat y)$ are nonnegative and $(\pi,y)\le(\hat\pi,\hat y)$, so $\sum_\omega b_\omega(\pi,y)\le\Psi(\pi,y)\le\Psi(\hat\pi,\hat y)$ by the dominance and by (iii). Also $\sum_\omega\pi_\omega\le e^S\cosh A-1$ is bounded, so the errors add up to $o(1)Y$. Without classes $\sum_\omega b_\omega=B\sum_\omega x^{\boldsymbol n(\omega)}$, which $B(e^{S(x)}\cosh A(x)-1)$ dominates, its coefficient being $B$ on every squarefree monomial and nonnegative on the others. For the last sentence of (ii): the coefficient of $\Psi$ on the monomial of a selection is $B'-\hat g_{\boldsymbol n(\omega)}\ge c_\omega$, since $c_{\boldsymbol n(\omega)}=1$, and on the other monomials it is nonnegative; distinct selections have distinct monomials, so this is the dominance. (iii) Every coefficient of $\Psi$ is nonnegative. If $0<\sum_G\pi\le\hat\Pi_G$, then $\hat\pi_g=\pi_g\hat\Pi_G/\sum_G\pi\ge\pi_g$ and $\sum_G\hat\pi_g=\hat\Pi_G$. If $G$ is nonempty and the actual total is zero, all its prices are zero; assign the upper total to any one variable and zero to the others. Empty groups need no allocation. (iv) On the monomial of a selection the coefficient of $B'(e^{S(x)}\cosh A(x)-1)-\mathcal D(x)$ is $B'-d_{\boldsymbol n}\ge c_\omega$, and on every other monomial it is $B'c_{\boldsymbol n}-d_{\boldsymbol n}\ge0$; this is the dominance of (ii), both series converging absolutely at $\hat\pi$. (v) By the multinomial expansion of $\cosh A(x)$, the monomials of $B'(e^{S(x)}\cosh A(x)-1)$ of degree $n_l$ in the skew variables of kind $l$ for every $l$ and of degree zero in all other variables sum to $B'\prod_lA_l(x)^{n_l}/\boldsymbol n!$: the coefficient of such a monomial $x^{\boldsymbol m}$ in $\prod_lA_l^{n_l}$ is $\boldsymbol n!/\boldsymbol m!$, and in $e^{S}\cosh A$ it is $1/\boldsymbol m!$. These monomials are the monomials of the selections of $\mathcal C_{\boldsymbol n}$ and of the tuples of that degree with a repeated atom. By the hypothesis on $\Psi_0$, subtracting $B'\prod_lA_l^{n_l}/\boldsymbol n!$ sets their coefficients to zero and leaves all other coefficients of $\Psi_0$, which dominate the $b_\omega$ of the selections outside $\mathcal C_{\boldsymbol n}$ (those of $\mathcal C_{\boldsymbol n}$, in no class for $\Psi_0$, contributed only to these monomials). The added polynomial $\bigl[C_{\boldsymbol n}\prod_l(A^{\rm arm}_l)^{n_l}+B'\bigl(\prod_l(A^{\rm lead}_l+A^{\rm rem}_l)^{n_l}-\prod_l(A^{\rm lead}_l)^{n_l}\bigr)\bigr]/\boldsymbol n!$ is a polynomial in the auxiliary variables with nonnegative coefficients, so $\Psi$ has nonnegative coefficients. It dominates $\sum_{\omega\in\mathcal C_{\boldsymbol n}}\phi_\omega$. A selection of $\mathcal C_{\boldsymbol n}$ is a set of distinct atoms with one record of kind $l$ at $n_l$ of them; it corresponds to exactly $\boldsymbol n!$ tuples $((\Blk_1,t_1),\dots,(\Blk_{|\boldsymbol n|},t_{|\boldsymbol n|}))$ whose first $n_1$ entries lie in $\mathcal R_1$, the next $n_2$ in $\mathcal R_2$, and so on, with distinct atoms. So $\sum_{\omega\in\mathcal C_{\boldsymbol n}}\phi_\omega$ is $1/\boldsymbol n!$ times the sum of $C_{\boldsymbol n}\prod_iy^{\rm arm}_{\Blk_i,t_i}+B'\bigl(\prod_i(y^{\rm lead}_{\Blk_i,t_i}+y^{\rm rem}_{\Blk_i,t_i})-\prod_iy^{\rm lead}_{\Blk_i,t_i}\bigr)$ over these tuples. The sum of the same expression over all tuples, the atoms not required to be distinct, is the added polynomial, by expanding the products of the totals; and every expression in the sum has nonnegative coefficients, the bracket being the sum of the products in which at least one remainder price occurs. So dropping the distinctness adds only nonnegative coefficients, and $\Psi$ dominates $\sum_\omega b_\omega$. Several degree vectors concern disjoint sets of monomials in $x$ and add disjoint nonnegative polynomials in $y$, so their replacements add. For the credits: on a monomial of a selection $\omega$ of $\mathcal C_{\boldsymbol n}$ the coefficient of $\Psi-\Gamma$ is at least that of $\phi_\omega-\gamma_\omega$, and on every other monomial at least that of $\sum_\omega b_\omega$; this is the dominance of (ii) for the credited class bounds, and it implies that $\Psi-\Gamma$ has nonnegative coefficients. \end{proof} \begin{remark}[Completion and subtraction]\label{rem:completion-subtraction} Parts (iv) and (v) are the only ways in which a discount is subtracted from the reserved cost, and they fix the order of operations of the closing (\cref{cert:closing}, which takes for $B'$ the certified upper end of $B$): every genuine selection first receives its nonnegative coefficient, the cost of its class after its credits ($B'-d_{\boldsymbol n}\ge c_\omega$ in (iv)) or its credited class bound (in (v)); the monomials with a repeated atom receive nonnegative coefficients ($[0,B'c_{\boldsymbol n}]$ in (iv)); only then is the series rewritten as an exponential minus homogeneous polynomials in the totals of the price variables and of the auxiliary variables and evaluated at the upper prices. The homogeneous terms are not lower bounds for a distinct-block discount, and no claim is made that a subtracted polynomial, considered alone, is a lower bound for the saving from distinct blocks. The finite gates of the closing which say that every coefficient stays nonnegative after the credits (every leading class cost $C_{n,m}\ge0$, every credited coefficient nonnegative, every restoration gain --- the factor in $[0,1)$ by which a restored variance credit (\cref{sec:variance}) multiplies a class coefficient --- in $[0,1)$) are exactly the conditions of (iv) and (v); that a class is replaced only when its saving is positive is a choice, not a condition of (v), which holds whatever the sign of the saving. Two rules govern the subtractions in this paper: an upper bound for a quantity is never used as a lower bound for it; and a discount is subtracted only inside an expression with nonnegative coefficients in the same chosen variables, as in (iv) and (v). In the replaced form (v) the remainder polynomial contains only the separately proved leading prices $y^{\rm lead}$ and the remainder prices $y^{\rm rem}$; neither a raw arm price nor the difference of a full price and a remainder price may replace a leading price there, since neither bounds the leading part of a record change. The same completion bounds other polynomials with nonnegative coefficients. If $0\le\kappa_b\le\kappa_H$ and $v_\Blk,w_\Blk\ge0$, then \[ \kappa_H\prod_\Blk(1+v_\Blk+w_\Blk)-(\kappa_H-\kappa_b)\prod_\Blk(1+v_\Blk) \] has coefficient $\kappa_b$ on the monomials in the $v_\Blk$ alone and $\kappa_H$ on all others, all squarefree, and it is nondecreasing in every $v_\Blk$ and every $w_\Blk$ separately: its derivative in $w_\Blk$ is $\kappa_H\prod_{\Blk'\ne\Blk}(1+v_{\Blk'}+w_{\Blk'})\ge0$, and its derivative in $v_\Blk$ is at least $\kappa_b\prod_{\Blk'\ne\Blk}(1+v_{\Blk'})\ge0$. Hence, for chosen upper prices $m_\Blk\ge v_\Blk$ and $n_\Blk\ge w_\Blk$ with $\sum_\Blk(m_\Blk+n_\Blk)\le U$, it is at most its value at $(m,n)$, which is at most $\kappa_He^U-(\kappa_H-\kappa_b)e^{\sum_\Blk m_\Blk}$: the expansion of the latter has the same coefficients $\kappa_b$, $\kappa_H$ on the squarefree monomials and nonnegative ones on all others. An upper price of the invariant tags may thus stand in the subtracted exponential, because the form is monotone in the tag variables; it is never used as a lower bound of a norm (\cref{lem:oct24:invariant-background,thm:envelopes}). \end{remark} \subsection{When a change preserves half-marginals its bound is a variance} When a comparison law replaces a record by a law with the same actual half marginals at $\iota$, the difference annihilates the constants on both sides, and its form against the bracket is a \emph{variance}: the energy of the record's selected diagonal minus that of the product of its actual half marginals. This is the interface between the variance credits of Part~V and the class bounds (CP5): a lower bound for the product energy lowers the coefficient of the class below $B$. \begin{lemma}[Variance form at the reserved cut] \label{lem:record:variance-interface} Assume (CP1)--(CP3) and (CP8) of \cref{thm:comparison}. Let $X$ be a nonempty finite set of atoms and, for $\Blk\in X$, let $m_\Blk$ be a probability measure on the plus-half labels $X_\Blk^{V_+}$ at $\iota$ with $\operatorname{Diag}_\iota(m_\Blk)$ and $J_\iota(m_\Blk)$ admissible, and $\Delta_\Blk$ a self-adjoint or skew-adjoint operator on $L^2(m_\Blk)$ with $\Delta_\Blk\one=\Delta_\Blk^*\one=0$ and $\|\Delta_\Blk\|\le\gamma_\Blk$, the number of skew-adjoint $\Delta_\Blk$ being even. Put $m_X=\bigotimes_\Blk m_\Blk$, $\operatorname{Diag}_X=\bigotimes_\Blk\operatorname{Diag}_\iota(m_\Blk)$, $J_X=\bigotimes_\Blk J_\iota(m_\Blk)$, and let $\zeta$ be the signed measure on $X_X^V$ whose cut operator at $\iota$ relative to $m_X$ is $\Delta_X=\bigotimes_\Blk\Delta_\Blk$. Then: \begin{enumerate}[label=(\roman*)] \item $Y^{\Nbr}[\operatorname{Diag}_X]\ge Y^{\Nbr}[J_X]$ and $|Y_{\zeta\otimes\lambda_{-X}}|\le\prod_\Blk\gamma_\Blk\, \bigl(Y^{\Nbr}[\operatorname{Diag}_X]-Y^{\Nbr}[J_X]\bigr)$; \item $Y^{\Nbr}[\operatorname{Diag}_X]\le(B+o(1))C_XY$ and $Y^{\Nbr}[J_X]\ge Y[J_X]-(R_{\rm err}+o(1))C_XY$; \item consequently, if $Y^{\Nbrz}[J_X]\ge(\ell-o(1))Y$ with $\ell\ge0$ and $C_X\le\bar C$, then \[ |Y_{\zeta\otimes\lambda_{-X}}|\le\prod_\Blk\gamma_\Blk\,C_X\bigl(B-g+o(1)\bigr)Y, \qquad g=\max\bigl(0,\ell/\bar C-R_{\rm err}\bigr). \] \end{enumerate} By \ref{it:record:E2}, as in the proof of (ii), $Y^{\Nbrz}[J_X]\ge Y[J_X]$, so the hypothesis of (iii) holds for every lower bound $\ell$ of $Y[J_X]$; positive background terms of the expansion of $\Nbrz$ may be added to such a bound (\cref{prop:background-variance}). Only $\Nbrz\succeq_\iota\mu$ and the priced difference $\Nbr-\Nbrz$ are used, not an order between $\Nbr$ and $\mu$. The $o(1)$ consists of energy errors and large-product remainders. \end{lemma} \begin{proof} (i) The number of skew-adjoint factors is even, so $\Delta_X$ is self-adjoint. As $\Delta_\Blk\one=\Delta_\Blk^*\one=0$, $\Delta_X$ and $\Delta_X^*$ annihilate every vector with a constant factor, in particular the constants of $L^2(m_X)$; so $\Delta_X=(I-\Jproj)\Delta_X(I-\Jproj)$ and, with $\gamma=\prod_\Blk\gamma_\Blk\ge\|\Delta_X\|$, $\gamma(I-\Jproj)\pm\Delta_X\succeq0$. Relative to $m_X$ the cut operators of $\operatorname{Diag}_X$ and $J_X$ are $I$ and $\Jproj$, so $\gamma(\operatorname{Diag}_X-J_X)\pm\zeta\succeq_\iota0$, and \ref{it:record:P5} gives the second assertion; the first is the case $\Delta_X=0$. (ii) $\operatorname{Diag}_X$ and $J_X$ are admissible probability measures, so \ref{it:record:E1} gives the first bound and $|Y^{\Nbr}[J_X]-Y^{\Nbrz}[J_X]|\le(R_{\rm err}+o(1))C_XY$; moreover $J_X\succeq_\iota0$, its cut operator being a projection, so $Y^{\Nbrz}[J_X]\ge Y[J_X]$ by \ref{it:record:E2}. (iii) By (i), the first bound of (ii), \ref{it:record:E1} for $\Nbr-\Nbrz$ at $J_X$ and the hypothesis, $Y^{\Nbr}[J_X]\ge Y^{\Nbrz}[J_X]-(R_{\rm err}+o(1))C_XY\ge(\ell-o(1))Y -(R_{\rm err}+o(1))C_XY$, and so $|Y_{\zeta\otimes\lambda_{-X}}|\le\gamma(BC_X+R_{\rm err}C_X-\ell+o(1))Y$. If $\ell/\bar C\le R_{\rm err}$, use instead $|Y_{\zeta\otimes\lambda_{-X}}|\le\gamma Y^{\Nbr}[\operatorname{Diag}_X]\le\gamma(B+o(1))C_XY$, valid as $Y^{\Nbr}[J_X]\ge0$ by \ref{it:record:E2}. Otherwise $\ell\ge C_X\ell/\bar C$, whence the claim, as $C_X\ge1$. \end{proof} \subsection{Energies of the dominators for \texorpdfstring{$\nu$}{nu} are at most \texorpdfstring{$Be^TR_I^kY$}{B e\textasciicircum T R\_I\textasciicircum k Y}} Two places need energies not of $\nu$ itself but of the laws $M_\Blk$ that dominate it in (CP6): the index-support inequality, which bounds the signed form $J_\nu$ by such energies with random inclusion of the index coordinates, and the wrapping terms, which need the same energies at a fixed interval. The lemma bounds both: writing $M_\Blk=\Nbr_\Blk+Q_\Blk$, the excess $Q_\Blk$ with total price $T_Q$ contributes a factor $e^{T_Q}$, and each coupled query contributes its conductor moment $R_I$. \begin{lemma}[Envelope energies]\label{lem:envelope-energy} Assume (CP0), (CP1), (CP2)(b), (CP3) and (CP8) of \cref{thm:comparison}. For every atom let $M_\Blk=\Nbr_\Blk+Q_\Blk$, with $Q_\Blk$ a nonnegative combination of admissible positive reserved-diagonal laws and $\sum_\Blk\|Q_\Blk\|q_\Blk^{2a}\le T_Q$, the prices $\|Q_\Blk\|q_\Blk^{2a}$ satisfying the summability condition of (CP8)(c) (as those of (CP4)(b) and (CP6) do). Let $\mathcal S\subseteq\mathcal E_k$, and for $e\in\mathcal S$ let $b_e$ be uniform on $\Z/\Kint\Z$ ($\kappa_e=1$) or fixed ($\kappa_e=\Kint$) and $s_e$ uniform on $\Z/\Mzero\Z$, all independent. Let $X$ carry $g^{I_{b_e},\Mzero,s_e}$ at the source $u_e$ of each $e\in\mathcal S$ and $F_A$ at every other slot of $V_+$, and let $V=\E_\Jc\E_\omega\ip{X^\Jc}{C_\iota(\bigotimes_\Blk M_\Blk)X^\Jc}$ be its single-half random-inclusion energy, where $\Jc$ reveals every uniform interval coordinate and independent prime-power depths with the tails $\delta_{p,j}$ of (CP0)(d) (for $\mathcal S=\mathcal E_k$ and uniform intervals, $V=V_{\otimes M}(X)$ of \cref{def:hyb:coupled}). Then \[ V\le\Bigl(Be^{T_Q}\prod_{e\in\mathcal S}\bigl(\kappa_e^{2\theta/d}R_I\bigr) +o(1)\Bigr)Y , \] and the same holds with the inputs at the reflected targets $\iota(v_e)$. The $o(1)$ consists of energy errors and large-product remainders. \end{lemma} With $\mathcal S=\mathcal E_k$, uniform intervals and $Q_\Blk=M_{s,\Blk}-\Nbr_\Blk$ of (CP6), this is $V_s\le(Be^TR_I^k+o(1))Y=(2^kJ+o(1))Y$ with $J=Be^T(R_I/2)^k$, as in \cref{thm:comparison}. \begin{proof} Fix $\Jc$ and the intervals. The revealed depths determine $s_e$ modulo $D_{\Jc_e}=\prod_p p^{J_{e,p}}$, a divisor of $\Mzero$. By \cref{lem:twointerval} and the disjointness of the endpoints, as in \cref{cor:index-support-frame}(ii), $X^\Jc$ carries $g^{I_{b_e},D_{\Jc_e},s_e\bmod D_{\Jc_e}}$ at $u_e$ ($e\in\mathcal S$); these support projections come before any fold, as (O3) requires. By \eqref{eq:cc:bilinear}, $\ip{X^\Jc}{C_\iota(\bigotimes_\Blk M_\Blk)X^\Jc}$ is the energy of $\bigotimes_\Blk M_\Blk$ with the input of $u$ at $u$ and at $\iota u$ ($u\in V_+$): each $e\in\mathcal S$ has the two changed slots $u_e$, $\iota u_e$, each of coarse price $(\Kint\sq(D_{\Jc_e}))^{a/d}\kappa_e^{\theta/d}$ (\cref{def:record:structured-energy}, with the square step of \cref{lem:record:fibre-scale}). Expand the outside laws fully and split by the total selected union as above; the large unions contribute one aggregate $o(1)Y$. For the small unions, start with $\bigotimes_\Blk M_\Blk=\sum_Z\bigotimes_{\Blk\in Z}Q_\Blk\otimes\Nbr_{-Z}$ over the finite sets $Z$ of atoms. Each $\bigotimes_{\Blk\in Z}Q_\Blk$ is admissible and positive, so the small-union part of the proof of \cref{lem:bracket-energy} bounds its contribution by $(B+o(1))\prod_{\Blk\in Z}\|Q_\Blk\|\,\Pi_ZY$, where $\Pi_Z=C_Z\prod_{e\in\mathcal S}(\Kint\sq(D_{\Jc_e}))^{2a/d}\kappa_e^{2\theta/d}$. Since $\sum_Z\prod_{\Blk\in Z}\|Q_\Blk\|q_\Blk^{2a}=\prod_\Blk(1+\|Q_\Blk\|q_\Blk^{2a}) \le e^{T_Q}$, the energy at fixed $\Jc$ is at most $(B+o(1))e^{T_Q}\prod_{e\in\mathcal S}(\Kint\sq(D_{\Jc_e}))^{2a/d} \kappa_e^{2\theta/d}\,Y$. In \cref{lem:bracket-energy} the conductors stay fixed through every fold and geometric mean, and complementary folds keep two occurrences of each conductor (\cref{lem:record:folded-energy}(e), (O4)). Only now average over $\Jc$: the $\Jc_e$ are independent with the law of (CP0)(d), so $\E_\Jc\prod_{e\in\mathcal S}(\Kint\sq(D_{\Jc_e}))^{2a/d} =R_I^{|\mathcal S|}$, and the errors are uniform in $\Jc$. For the reflected targets use the slots $\iota(v_e)$ and $v_e$. \end{proof} \begin{remark}[The trivial mean credit and the bookkeeping of the closing] \label{lem:record:domination} Assume (CP1)--(CP3), (CP6) and (CP8). For every atom and $s\in\{{\rm L},{\rm R}\}$, $M_{s,\Blk}\pm\lambda_\Blk=(\Nbr_\Blk\pm\lambda_\Blk)+(M_{s,\Blk}-\Nbr_\Blk) \succeq_\iota0$: the first summand by (CP3) (off the first-stage atoms $\Nbr_\Blk\pm\lambda_\Blk$ is $2\mu_\Blk$ or $0$), the second by \ref{it:record:E3}. By \cref{lem:record:block-gram}(d), $\bigotimes_\Blk M_{s,\Blk}\pm\bigotimes_\Blk\lambda_\Blk\succeq_\iota0$, and at $\bar X$ this is $e_s\ge Y_\lambda\ge(1-L_0-o(1))Y$ (\cref{lem:record:first-stage}). Hence (CP7) holds with the trivial credit $m=1-L_0$, and then $\Theta=(1-2^{-k})(L_0+\mathcal E)+J+W+2^{-k}L_0=L_0+(1-2^{-k})\mathcal E+J+W$: the first-stage loss enters $2^k-1$ times through $Y_\nu$ and once through the mean credit, so it keeps coefficient one, as do the matching term and the wrap, and only the reserved cost drops to $1-2^{-k}$. No resource is counted twice: the class bounds and credits enter only through the reserved cost, a separate inequality between $Y_\nu$ and $Y_\lambda$ (\cref{lem:record:record-expansion}); the matching prices enter only through the bounds for $V_{\rm L}$, $V_{\rm R}$ (\cref{lem:envelope-energy}); and this credit uses no price at all, only positivity, and no order between $\Nbr$ and $\mu$. The construction uses the larger credit of \cref{prop:record:mean-credit} for (CP7); this remark is not one of its premises. \end{remark} \paragraph{Consequences and what to read next.} From Part~II: cut matrices, their order and the Kronecker rule (\cref{def:cc:order}, \eqref{eq:cc:bilinear}, \eqref{eq:cc:kron}, \cref{def:rp}, \cref{rem:cut-symmetries}), the common-cut order (\cref{lem:commoncut}), the block-Gram calculus (\cref{lem:record:block-gram}) and the sector lemma (\cref{lem:sector}); the functional, its inputs, the index averages and the reference hypotheses (\cref{def:record:functional}, \cref{lem:twointerval}, \cref{hyp:record:reference}); structured energies and their estimate, folded energies, admissibility, the square step, the cancellation and the large products (\cref{def:record:structured-energy,prop:record:density-structured,% lem:record:folded-energy,def:admissible,lem:record:fibre-scale,% lem:record:density-can,lem:record:density-lp}), at a least normalized counterexample (\cref{def:record:counterexample}). From Part~III: the frame data and hypotheses of \cref{thm:comparison}, the index law, the nonvanishing square classes and the signed index form (\cref{def:hyb:coupled}, \cref{lem:func:unitsq}, \eqref{eq:record:expansion}), the comparison law (\cref{def:record:comparison-law}) and the prices (\cref{def:price}). \space % End sections/10_comparison_lemmas % Begin sections/11_comparison_proof \providecommand{\PushA}{\frac{5422587}{6103515625}} \providecommand{\PushK}{890666} \providecommand{\PushTheta}{0.99999999997327} \section{From the five estimates to Theorem~C} \label{sec:comparison-proof} \paragraph{What this section proves and how to read it.} This section proves Theorem~C. The closing inequality (\cref{thm:record:criterion}) combines the wrapping bound $W$, the mean energies $e_{\rm L},e_{\rm R}$ and the envelope energies $V_{\rm L},V_{\rm R}$ of the previous section with the first comparison: at a least counterexample, $1\le\Theta+o(1)$. The robustness lemma (\cref{lem:record:rec}) shows that every $o(1)$ in this chain is produced by structured energies and by the two analytic remainders, so that the density-linear induction of \cref{thm:record:lineardensity} applies. The section ends with the proof of the one-query proposition (\cref{rem:cp:one-query}) and with \cref{tab:hypotheses}, which records where Part~V verifies each hypothesis. \subsection{At a least counterexample, \texorpdfstring{$1\le\Theta+o(1)$}{1 <= Theta+o(1)}}\label{subsec:cp:closing} This lemma is where the comparison closes: the five estimates of \cref{sec:comparison-lemmas} combine to show that a least counterexample forces $1\le\Theta+o(1)$. Hence $\Theta<1$ rules out a counterexample at large scale, which is the contradiction behind Theorem~C. \begin{lemma}[Closing inequality]\label{thm:record:criterion} Assume (CP0)--(CP4), (CP6) and (CP8). Let $\mathcal E$ and $m$ be numbers such that, at every least normalized counterexample, \begin{enumerate}[label=(\roman*)] \item $Y_\nu\ge Y_\lambda-(\mathcal E+o(1))Y$, and \item $\frac12(e_{\rm L}+e_{\rm R})\ge(m-o(1))Y$. \end{enumerate} Then, at every least normalized counterexample, \begin{equation}\label{eq:record:criterion} 1\le\Theta(\mathcal E,m)+o(1),\qquad \Theta(\mathcal E,m)=\bigl(1-2^{-k}\bigr)\bigl(L_0+\mathcal E\bigr)+J+W +\frac{1-m}{2^k}, \end{equation} with $J$ and $W$ as in \cref{thm:comparison}. Consequently, if $\Theta(\mathcal E,m)<1$, no least normalized counterexample exists with $\Lsc$ sufficiently large. \end{lemma} \begin{proof} By \cref{lem:record:wrap-expansion}, \begin{equation}\label{eq:cp:wrap-step} 2^kY_\nu\le J_\nu+(2^kW+o(1))Y . \end{equation} The index-support lemma, in the form of \cref{cor:index-support-frame}, applies to the signed index operator $\mathcal T=\bigotimes_e(2P_e-T_e)$, the joint bracket of the envelopes of (CP6) tensorized over the finitely many atoms of $\mathcal A_N$, and the half-functions $X_\omega$, $Y_\omega$, whose means are $\bar X$. Its mean term is $Y_\nu$, its mean energies are the $e_s$ of (CP7), and its random-inclusion energies are $V_{\rm L}=V_{\bigotimes M_{\rm L}}(X)$ and $V_{\rm R}=V_{\bigotimes M_{\rm R}}(Y)$ (\cref{def:hyb:coupled}(f)). By \eqref{eq:index-support-frame}, \begin{equation}\label{eq:cp:mean-step} J_\nu\le Y_\nu+\tfrac12\bigl[(V_{\rm L}-e_{\rm L})+(V_{\rm R}-e_{\rm R})\bigr]. \end{equation} By \cref{lem:envelope-energy}, applied with $Q_{\Blk}=M_{s,\Blk}-\Nbr_{\Blk}$ and $T_Q=T$ (CP6), $V_{\rm L},V_{\rm R}\le(Be^TR_I^k+o(1))Y=(2^kJ+o(1))Y$. With (ii), \eqref{eq:cp:wrap-step} and \eqref{eq:cp:mean-step} give \[ (2^k-1)\,Y_\nu\le\bigl(2^kJ-m+2^kW+o(1)\bigr)Y . \] By (i) and \cref{lem:record:first-stage}, $Y_\nu\ge(1-L_0-\mathcal E-o(1))Y$. Since $Y>0$ and $2^k-1>0$, $(2^k-1)(1-L_0-\mathcal E)\le2^kJ-m+2^kW+o(1)$, that is, $2^k\le(2^k-1)(L_0+\mathcal E)+2^kJ+2^kW+(1-m)+o(1)$; dividing by $2^k$ gives \eqref{eq:record:criterion}. The last assertion follows because $o(1)\to0$ as $\Lsc\to\infty$, uniformly over square-difference-free $A\subseteq[\Kint\Lsc]$. \end{proof} \begin{corollary}[Joint comparison and mean allocation]\label{cor:joint-closing} The comparison loss $Y_\lambda-Y_\nu$ and the mean energies $e_{\rm L},e_{\rm R}$ enter the preceding proof with opposite signs. It suffices to bound their combined contribution. The separate bounds (i) and (ii) in \cref{thm:record:criterion} may be replaced by a single robust bound. Suppose that, for some real constant $\mathcal H$, \[ (2^k-1)(Y_\lambda-Y_\nu)-\tfrac12(e_{\rm L}+e_{\rm R}) \le (2^k\mathcal H-1+o(1))Y. \] Then the resulting closing number is \[ \Theta=(1-2^{-k})L_0+J+W+\mathcal H. \] In particular, positive comparison energies and negative mean energies may first be combined on the same labelled diagonal. If their residual coefficients are nonnegative, their common energies may then be bounded by upper prices and completed to exponential series. \end{corollary} \begin{proof} Keep the mean energies in \eqref{eq:cp:mean-step} until after combining that inequality with \eqref{eq:cp:wrap-step}. This gives \[ (2^k-1)Y_\lambda\le (2^k(J+W)+o(1))Y +(2^k-1)(Y_\lambda-Y_\nu)-\tfrac12(e_{\rm L}+e_{\rm R}). \] Use the displayed joint bound and $Y_\lambda\ge(1-L_0-o(1))Y$, and divide by $2^k$. Nonnegative residual coefficients permit exactly the positive completion argument of \cref{lem:record:record-expansion}; applying an upper price to an isolated negative mean term would not permit it. The robustness proof of \cref{lem:record:rec} applies to the combined positive series, with the same two kinds of analytic remainder. \end{proof} \begin{remark}[The trivial value of the mean constant]\label{rem:cp:trivial-mean} By \cref{lem:record:domination}, hypothesis (ii) always holds with $m=1-L_0$, and then $\Theta(\mathcal E,1-L_0)=L_0+(1-2^{-k})\mathcal E+J+W$; that remark explains this bookkeeping. A larger $m$ lowers $\Theta$ by $(m-1+L_0)/2^k$; Part~V proves $m>1$ (\cref{prop:record:mean-credit}). \end{remark} \subsection{Every error term comes from the two allowed remainders}\label{subsec:cp:robust} The hypothesis (Rec) of \cref{thm:record:lineardensity} asks for the closing inequality with every analytic error made explicit: every structured-energy bound inflated by the factor $1+z$, every remainder bounded by $zY$, and a closing number $\Theta(z)$ continuous at $z=0$. The next lemma supplies it and records how each $o(1)$ above arises. \begin{lemma}[The recurrence hypothesis]\label{lem:record:rec} Assume (CP0)--(CP8). \begin{enumerate}[label=(\roman*)] \item\emph{Robust bounds.} Exact same-scale relations (identities and inequalities between quantities at the same scale, with no error term) hold unchanged at every $z$-inflated counterexample. A bound $\Xi\le(c+o(1))Y$ obtained by applying \cref{prop:record:density-structured}, directly or through \cref{lem:record:folded-energy}, \ref{it:record:E1} or \cref{lem:bracket-energy}, to finitely many families of structured energies, summing with nonnegative coefficients bounded by convergent products of prices, and adding remainders of the forms of \cref{def:robust}(a), is robust: at a $z$-inflated counterexample its constant $c$ becomes $(1+z)c+c'z$, where $c'$ is a bound, independent of $\Lsc$ and $A$, for the coefficients multiplying the remainder integrals and sums in its derivation. An exact relation minus robust upper bounds is a robust lower bound. Let a bound be derived from finitely many robust bounds, with functions $c_1(z),\dots,c_n(z)$, by an argument that is valid whenever finitely many strict inequalities between the $c_i(z)$ and fixed numbers hold, and let its constant be $F(c_1,\dots,c_n)$, with $F$ continuous at $(c_1(0),\dots,c_n(0))$. If the strict inequalities hold at $z=0$, the bound is robust, with $c(z)=F(c_1(z),\dots,c_n(z))$. \item\emph{The lemmas.} The bounds of \cref{lem:energy-toolkit} and of \cref{lem:sharp-first,lem:record:first-stage,lem:bracket-energy,lem:record:wrap-expansion,lem:record:common-mean,cor:index-support-frame,lem:record:record-expansion,lem:record:variance-interface,lem:envelope-energy} are exact or robust for fixed selected sets. For the summed families used here, the full-union split of \cref{sec:comparison-lemmas} gives uniform $z_0$, $\Lsc_1$ and aggregate remainder coefficients. Their remainders are of two kinds: \begin{enumerate}[label=(\alph*)] \item the nonwrapping terms of \cref{lem:record:wrap-expansion}: for each of the at most $3^kn_\nu$ triples of a product component of $\nu$, an index subset and a subset of wrapping queries that does not contain every query of the subset (a \emph{wrap pattern with a nonwrapping query}), an integral of the form bounded in \cref{lem:record:density-can}, against a probability law of the indices, the coefficients of the product components for one pair $(X_\omega,Y_\omega)$ of half-functions adding up to at most $2^k\mathfrak v_\nu e^{P+S}$; \item the terms of the selections whose union $E$ of atoms has $q_E>N^\tau$, in finitely many sums of the form bounded in \cref{lem:record:density-lp} whose coefficients $\eta_{\Blk}$ are the prices of the selected laws after the operator-to-energy reduction of \cref{lem:record:rec}(ii) (the \emph{post-reduction prices}); together they have the bound of one such sum, with $c$ the sum of their constants, and with $\Pi_{\rm H}=\prod_\Blk(1+\eta_\Blk q_\Blk^{1/4})$ as in \cref{lem:record:density-lp}; neither $c$ nor $\Pi_{\rm H}$ depends on $\Lsc$ or $A$. \end{enumerate} \item\emph{The recurrence.} Let $\mathcal E$ and $m$ be numbers for which (i) and (ii) of \cref{thm:record:criterion} hold robustly. Then there are $z_0>0$, $\Lsc_1$ and a function $\Theta\colon[0,z_0]\to[0,\infty)$, continuous at $0$ with $\Theta(0)=\max(\Theta(\mathcal E,m),0)$, such that the hypothesis (Rec) of \cref{thm:record:lineardensity} holds; its remainders are those of (ii) together with those of the robust arguments for (i) and (ii) of \cref{thm:record:criterion}, and they have the forms that theorem requires. \end{enumerate} \end{lemma} \begin{proof} (i) An exact relation holds at every scale with no error term, so it needs no inflation, and a bound of the form $\Xi\le cY$ that it gives has $c(z)=c$. In a bound of the second kind each structured energy is at most $1+z$ times its main bound at a $z$-inflated counterexample; the coefficients are nonnegative, so the sum of the main bounds is multiplied by at most $1+z$; and the remainders, at most $zY$ in total, enter with coefficients at most $c'$, which by \cref{def:robust}(a) is independent of $\Lsc$ and $A$. If $\Xi\ge\Xi_0-U$ with $\Xi_0$ exact and $U\le u(z)Y$, then $\Xi\ge\Xi_0-u(z)Y$. In the last case, by continuity there is $z_0>0$ such that the strict inequalities hold for $0\le z\le z_0$; the argument then applies at every $z$-inflated counterexample with $z\le z_0$, and $F(c_1(z),\dots,c_n(z))\to F(c_1(0),\dots,c_n(0))$ as $z\to0$. The number of remainders and their coefficients remain bounded, being those of finitely many arguments. (ii) We go through the proofs of these statements. The following are \emph{exact relations}: $Y[\bigotimes_{\Blk}\mu_{\Blk}]=Y$; the orders \ref{it:record:E2} and \ref{it:record:E3} and the relations \ref{it:record:P1}--\ref{it:record:P5} of \cref{lem:energy-toolkit}, among them the product centred interpolation \ref{it:record:P3b}; the cut-order and bracket manipulations (\cref{eq:cc:kron}, \cref{lem:record:block-gram}, part (i) of \cref{lem:record:variance-interface}); the vanishing of the terms with an odd number of skew factors in \cref{lem:record:record-expansion}; Step~1 of the first comparison, which is (CP2)(a); the identity \eqref{eq:record:expansion}; and the inequalities of \cref{lem:record:common-mean} and \cref{cor:index-support-frame}, which hold for arbitrary vectors and envelopes. The following are upper bounds of the second kind of (i): \ref{it:record:E1}; the tagged expansion \cref{lem:sharp-first}, which bounds each term of the tagged series, indexed by the numbers of summands of the two tags, by the product of the sharp norms of one tag times the geometric mean of two folded energies (\cref{lem:record:folded-energy}(a), (d$'$), (e)), the tag used for a category being chosen from the prices alone, so that the bound is again a sum of structured energies with nonnegative coefficients, and is used for Step~2 of \cref{lem:record:first-stage}; \cref{lem:bracket-energy}, the same expansion with the bracket outside, in which the geometric mean of two inflated factors of a Cauchy--Schwarz step is again inflated by $1+z$, so that $B$ becomes $(1+z)B$ and not $(1+z)^2B$; the small-union bound underlying $|I_\omega|\le(B+o(1))\pi_\omega Y$ of \cref{lem:record:record-expansion}(i); the energy bounds of \cref{lem:envelope-energy} and of the wrapping terms of \cref{lem:record:wrap-expansion}, in which the conductors are held fixed through every fold and averaged only at the end ((O3) of \cref{def:admissible}); and the upper bound in \cref{lem:record:variance-interface}(ii). Each of these is a sum of structured energies with nonnegative coefficients bounded by convergent price products such as $e^P\tagser(d,v)$, $e^{U_0}\tagser(d,v)$, $e^{S+A}$ and $e^T$. The following are lower bounds of the third kind: the first comparison $Y_\lambda\ge(1-L_0-o(1))Y$, which is Step~1 minus Step~2; the bound $Y^{\Nbr}[J_X]\ge Y[J_X]-(R_{\rm err}+o(1))C_XY$ of \cref{lem:record:variance-interface}(ii), which is \ref{it:record:E2} minus \ref{it:record:E1}; and the gain $\max(0,\ell/\bar C-R_{\rm err})$ of \cref{lem:record:variance-interface}(iii), a continuous function of robust bounds. Finally, \cref{lem:record:record-expansion}(ii), (iii) combine the bounds of (i) of that lemma with the class bounds of (CP5), which are robust uniformly in the class by (CP8)(b), through the complete polynomial $\Psi$. The series $\sum_\omega b_\omega$ that $\Psi$ dominates has as coefficients $B$, the scalars $c_{\mathcal C}$ and the coefficients of the class bounds; at a $z$-inflated counterexample these become functions of $z$ that converge to them uniformly over the classes, and we may replace each by its positive part, while the errors $o(1)\pi_\omega$ of (CP5) become $\epsilon(z)\pi_\omega$ with one function $\epsilon(z)\to0$. Adding to $\Psi$ the positive parts of the changes of the $b_\omega$, and $\epsilon(z)(e^{S(x)}\cosh A(x)-1)$, gives a series $\Psi_z$ with nonnegative coefficients that dominates the inflated bounds. The difference $\Psi_z(\hat\pi,\hat y)-\Psi(\hat\pi,\hat y)$ is at most the largest change of a coefficient times the sum of the values at $(\hat\pi,\hat y)$ of the monomials of the $b_\omega$, plus $\epsilon(z)(e^{\hat S}\cosh\hat A-1)$. That sum is finite: the monomials in the prices sum to at most $e^{\hat S}\cosh\hat A-1$, since distinct selections have distinct squarefree monomials, and those of the class bounds to at most $\prod_\Blk(1+\sum_j\hat y_{\Blk,j})$, since each of them contains one auxiliary price of each atom of its selection and determines the selection (CP5); this product is finite because $\hat y$ has a finite total. So $\Psi_z(\hat\pi,\hat y)$ tends to $\Psi(\hat\pi,\hat y)$ as $z\to0$. The remainders. By \cref{lem:record:wrap-expansion}, whose proof splits the term of an index subset $\mathcal S$ by the set of its wrapping queries (each query is of exactly one of three kinds: in $\mathcal S$ and wrapping, in $\mathcal S$ and nonwrapping, or outside $\mathcal S$), the nonwrapping terms are at most $3^kn_\nu$ integrals of the form bounded in \cref{lem:record:density-can}, one for each product component of $\nu$, against the conditional law of the indices, with coefficients adding up to at most $2^k\mathfrak v_\nu e^{P+S}$ for each pair; that proof also bounds the mass of $\nu$ by (CP2) and the brackets of (CP4). This is (a). The selections with $q_E>N^\tau$ occur in finitely many expansions, each of the form bounded in \cref{lem:record:density-lp} with post-reduction prices of the selected laws as the $\eta_{\Blk}$. Each law chosen at an atom in these expansions is one of the laws of (CP2)--(CP6) or a fold or normalization of one, so its price is at most the sum of the prices of the atom listed in (CP8)(c); the components of a signed comparison law are never selected laws, since they occur only in the cancellation of (a), so the variation factor $\mathfrak v_\nu$ does not enter here. Taking that sum as $\eta_{\Blk}$ for all the expansions, $\Pi_{\rm H}=\prod_{\Blk}(1+\eta_{\Blk}q_{\Blk}^{1/4})$ is finite by (CP8)(c); summing the finitely many sums gives the bound of one such sum. The number of terms and their coefficients do not depend on $\Lsc$ or $A$. This is (b). (iii) Let $(\Lsc,A)$ be a $z$-inflated least normalized counterexample, with $\Lsc$ and $z$ in the ranges of the finitely many robust bounds used. By (ii), the steps of the proof of \cref{thm:record:criterion} hold with each $o(1)$ replaced by the deviation of a function continuous at $0$: $2^kY_\nu\le J_\nu+2^kW(z)Y$; \eqref{eq:cp:mean-step} exactly; $V_{\rm L},V_{\rm R}\le2^kJ(z)Y$; and $Y_\lambda\ge(1-L_0(z))Y$, with $W(0)=W$, $J(0)=J$ and $L_0(0)=L_0$. By hypothesis, $Y_\nu\ge Y_\lambda-\mathcal E(z)Y$ and $\frac12(e_{\rm L}+e_{\rm R})\ge m(z)Y$, with $\mathcal E(0)=\mathcal E$ and $m(0)=m$. The algebra of that proof gives $Y\le\Theta(z)Y$ with \[ \Theta(z)=\bigl(1-2^{-k}\bigr)\bigl(L_0(z)+\mathcal E(z)\bigr)+J(z)+W(z) +\frac{1-m(z)}{2^k}, \] which is continuous at $0$ with $\Theta(0)=\Theta(\mathcal E,m)$; since $Y>0$, the inequality persists when $\Theta(z)$ is replaced by $\max(\Theta(z),0)$. This is (Rec), with $z_0$ the minimum and $\Lsc_1$ the maximum of the numbers $z_0,\Lsc_1$ of the robust bounds involved. Its remainders are those of (ii) and those of the robust arguments for (i) and (ii) of \cref{thm:record:criterion}; by \cref{def:robust}(a) they are finitely many integrals of the form of \cref{lem:record:density-can}, with coefficients bounded independently of $\Lsc$ and $A$, and finitely many sums of the form of \cref{lem:record:density-lp}, which together have the bound of one such sum with the sum of their constants $c$ and the largest of their products $\Pi_{\rm H}$. This is the second hypothesis of \cref{thm:record:lineardensity}. \end{proof} \begin{remark}[Robustness of the final chain]\label{rem:cp:robust-final} In Part~V every bound that enters (CP5) and (CP7) is of one of the kinds of \cref{lem:record:rec}(i). \begin{enumerate}[label=(\alph*)] \item\emph{Upper bounds of structured energies}, with nonnegative coefficients over certified prices: the direct prices of the middle records and their repricing (\cref{lem:middle-comparison-prices,lem:record:repricing}); the repriced first-stage totals and the tagged series, which give $U_0$, $B$, $R_{\rm err}$ and $L_0$ (\cref{cor:first-stage-repricing,cor:two-cut-series}); every leading class cost (with $n,m$ and $\kappa_H,\kappa_b,\Uinv,\delta_{\rm s}$ as in \cref{cor:envelope-costs}) \[ C_{n,m}=\kappa_He^{U_0}-(\kappa_H-\kappa_b)e^{t\Uinv}+M_{n,m}R_{\rm err} -M^{\rm inv}_{n,m}e^{t\Uinv}t\delta_{\rm s} \] whose terms are an outside energy, the invariant-background polynomial with nonnegative coefficients (\cref{lem:oct24:invariant-background,rem:completion-subtraction}), normalized couplings bounded by \ref{it:record:E1}, and an orbit coupon that lowers the coupling term by an exact orbit decomposition (\cref{lem:orbit-coupon}); the remainder polynomials $B\mathcal R_{n,m}$; $J$ and $W$; the upper prices $S_{\rm u}(a)$, $A_{\rm u}(a)$ (\cref{prop:record:upper}); and the complete polynomial after the repeated-block monomials are added with nonnegative coefficients (\cref{lem:record:record-expansion}(iv), (v)). \item\emph{Exact same-scale relations}: the orders \ref{it:record:E2}, \ref{it:record:E3} and \ref{it:record:P3b}; the operator comparison of the pair projections with their positive substitutes (\cref{lem:oct24:pure-pair-substitute}); the matrix-envelope orders and their mask form (\cref{lem:oct24:mask-schur}); the changes of variables of \cref{lem:reflection-averaging}; the orbit decomposition of \cref{lem:orbit-coupon}; the positive compressions of the aligned matching bridge (\cref{lem:record:paired-e-joint}(a), (c)); the all-degree polarization identity (\cref{lem:tr:polarization}); and the contraction and density steps of \cref{lem:record:companion-energy}. \item\emph{Exact relations minus upper bounds}: the restorations $l$ with the individual piece caps (\cref{lem:record:restoration,lem:piece-caps}; under inflation $l=\max(0,1-(C-1)h)$ becomes $\max(0,1-((1+z)C-1)h)$); the gains with positive backgrounds and the late-pool gains (\cref{prop:background-variance,lem:pool-coupons,lem:var-gain}), positive parts of continuous expressions; the selected-only aligned matching gain (\cref{lem:record:paired-e-joint,lem:class-credit}); the credited class bounds (\cref{lem:class-credit}); the variance credit $D_{\rm var}$ (\cref{cor:variance:final}); and the mean credit $m$ (\cref{prop:record:mean-credit}), which subtracts $R_{\rm err}e^{T_K+T_{QE}}$. \end{enumerate} The strict inequalities used are: every saving used in (a)--(c) has a stated positive lower bound; every restoration gain lies in $[0,1)$ with a positive denominator; the two-cut conditions $d<6$, $dv<36$ of \cref{cor:two-cut-series}; and the positive-mean branch; the closing and restoration scripts assert them with strict margins (\cref{tab:cert:finite}). Three further gates are nonnegativity conditions that need no margin. The orbit-coupon gate $M^{\rm inv}_{n,m}e^{t\Uinv}t\delta_{\rm s}\le M_{n,m}R_{\rm err}$ concerns the coefficient $M_{n,m}R_{\rm err}-M^{\rm inv}_{n,m}e^{t\Uinv}t\delta_{\rm s}$ of the coupling term, which is itself a bound of the kind (a) and so only grows under inflation. Every subtracted term $cg$ on a monomial in the auxiliary prices $y^{\rm arm}$ of a replaced class, a fixed envelope cap $c$ times a gain $g<1$, is below the coefficient $C_{n,m}$ of that monomial (\cref{lem:class-credit}); this gate is proved in the text, from $c\le\kappa_be^{t\Uinv}\le C_{n,m}$ (\cref{prop:closing-data}), not asserted by a script. Under inflation the coefficient, a bound of the kind (a), only grows, and the credit, its gain being of the kind (c), only shrinks. The restoration regime $0\le l\le C/2$ is kept by inflation, which lowers $l=\max\bigl(0,1-(C-1)h\bigr)$ and raises $C$. The side coefficients $k_s\ge0$, the side increments $\delta^+_{s,X}$ of \eqref{eq:signed-increment} and the bracket condition (\cref{prop:signed-sides,prop:record:matching,eq:protection}) are inequalities between fixed numbers that enter only exact bracket inequalities, so inflation does not affect them; the piece caps $1\le C_i\le e^{2aL}$ (\cref{lem:piece-caps}) and the domain $00$, $\Lsc_1$ and a function $\Theta(\cdot)$, continuous at $0$ with $\Theta(0)=\max(\Theta,0)<1$, for which (Rec) of \cref{thm:record:lineardensity} holds, with remainders of the forms that theorem requires. Its other hypotheses hold: $0{\raggedright\arraybackslash}p{2.75cm}>{\raggedright\arraybackslash}p{6.1cm}>{\raggedright\arraybackslash}p{5.95cm}@{}} \caption{Where the hypotheses of Theorem~C are verified.}\label{tab:hypotheses}\\ \toprule Hypothesis & What is shown & Proved in\\ \midrule \endfirsthead \toprule Hypothesis & What is shown & Proved in\\ \midrule \endhead \bottomrule \endfoot (CP0)(a) slots, cuts & $V$ sorted by seven folds; $\iota$ fixed-point free; the family $\mathfrak F$ & \cref{def:slot-array,lem:slot-array}\\ (CP0)(b) atoms, exponents, $a<\sigma$ & $a=\PushA<9/10000<\sigma=1/825$; inequalities (S1)--(S7); $\Kint=\PushK$; checked inequalities involving $a$ hold for $01$, then the same holds at every prime $p\ge P$, and there $\log(\max_xC(x)/\mathrm{main})\le r_p\,\mathfrak u(P)$ and $\log(\mathrm{main}/\min_xC(x))\le r_p\,\mathfrak l(P)$, where $r_p=p^{-1/2}$ and $\mathfrak u(P)$, $\mathfrak l(P)$ are evaluated at $r=P^{-1/2}$. \end{enumerate} \end{lemma} \begin{proof} Every edge not inside $A$ is counted exactly once in $\sum_it_i$, at its endpoint of largest index; this gives $\sum_it_i=|E|-|E(G[A])|$. \ref{it:seq:count} The elements of $\operatorname{Inj}_p(G)$ extending $x$ are obtained by choosing $y(v_1),y(v_2),\dots$ in turn. When $v_i$ is labelled, its $t_i$ labelled neighbours carry pairwise distinct labels (injectivity), and, since $G$ has at most one edge on each unordered pair, each of them imposes exactly one condition $\chi(y(v_i)-\beta)=s$, with $\beta$ its label. The new label must avoid the $|A|+i-1\le n-1$ labels used so far, which contain the roots. Conversely every sequence of choices satisfying these conditions gives an element of $\operatorname{Inj}_p(G)$ extending $x$: the edges inside $A$ are satisfied by $x$, every other edge at the step of its later endpoint. So the number of choices at step $i$ is the size of a set $\Phi$ of \cref{lem:extension} with $t_i$ roots and at most $n-1$ excluded labels, and it lies in $p2^{-t_i}[1-\epsilon^-_{t_i},1+\epsilon^+_{t_i}]$ whatever the earlier choices were. Multiplying over $i$ gives \ref{it:seq:count}. \ref{it:seq:marg} The marginal of $\lambda_p(G)$ at $x$ is $C(x)/\sum_{x'}C(x')$ and $\lambda_p(G[A])(x)=1/|\operatorname{Inj}_p(G[A])|$, so the density is $C(x)/\operatorname{mean}_{x'}C(x')$, which lies between $\min C/\max C$ and $\max C/\min C$, hence in the stated interval by \ref{it:seq:count}; it is positive everywhere on $\operatorname{Inj}_p(G[A])$. \ref{it:seq:rows} The probability is $C(x)/|\operatorname{Inj}_p(G[Z])|$. By \ref{it:seq:count}, $C(x)\in p^s2^{-|H|-|E(G[Z])|}[e^{-\mathrm{lo}},e^{\mathrm{up}}]$. By \ref{it:seq:count} for $G[Z]$ with no anchors and the same ordering, $|\operatorname{Inj}_p(G[Z])|\in p^s2^{-|E(G[Z])|}\prod_i[1-\epsilon^-_{t^0_i},1+\epsilon^+_{t^0_i}]$, where $t^0_i\le t_i$ is the number of earlier neighbours of $v_i$ in $Z$; since $\epsilon^\pm$ are nondecreasing in $t$, this interval lies in $p^s2^{-|E(G[Z])|}[e^{-\mathrm{lo}},e^{\mathrm{up}}]$. Divide. \ref{it:seq:coarse} The identity is the definition. If $e_\Delta(p,n)<1$ then $e_{t_i}(p,n)\le e_\Delta(p,n)<1$ by \ref{it:et:poly}, since $t_i\le\Delta$. \ref{it:seq:thresholds} By \ref{it:et:poly}, $\epsilon^\pm_t$ and $\epsilon^\pm_t/r$ are polynomials in $r$ with nonnegative coefficients. The functions $x\mapsto-\log(1-x)/x=\sum_{k\ge1}x^{k-1}/k$ and $x\mapsto\operatorname{artanh}(x)/x=\sum_{k\ge0}x^{2k}/(2k+1)$ are increasing on $(0,1)$, so $-\log(1-\epsilon^-)/r=\bigl(-\log(1-\epsilon^-)/\epsilon^-\bigr)(\epsilon^-/r)$ and $\log\frac{1+e}{1-e}/r=2\bigl(\operatorname{artanh}(e)/e\bigr)(e/r)$ are products of nonnegative nondecreasing functions of $r$ (this is an instance of \cref{lem:majorant}). Since $r_p\le P^{-1/2}$ for $p\ge P$, the hypothesis transfers from $P$ to $p$, and by \ref{it:seq:count} and $\log(1+x)\le x$, $\log(\max C/\mathrm{main})\le\sum_i\epsilon^+_{t_i}(p)=r_p\mathfrak u(p)\le r_p\mathfrak u(P)$; the other bound is the same argument. \end{proof} The next lemma collects the facts about one vertex, about subsets and about conditional laws of a graph law that the cut and spectral estimates use; its part \ref{it:vertex:tuple} is the density bound behind the extraction of \cref{lem:matching:extractionk}. \begin{lemma}[Vertices, subsets and conditional laws]\label{lem:graphs:vertex} Let $G=(W,E)$ be an oriented graph with $|W|\le n$, maximum degree $\Delta$ and $e_\Delta(p,n)<1$. Let $\lambda=\lambda_p(G)$, $d_w=\deg_G(w)$, and for $Y\subseteq W$ put \[ R_Y=\prod_{i\in Y}\frac{1+e_{d_i}(p,n)}{1-e_{d_i}(p,n)},\qquad d_i=\deg_G(i). \] \begin{enumerate}[label=\textup{(\alph*)}] \item\label{it:vertex:inv} $\lambda$ is invariant under the maps $z\mapsto(\alpha z_w+\beta)_{w\in W}$ with $\alpha\in\Qsq$, $\beta\in\Fp$, and its one-vertex marginals are uniform (\cref{lem:marginals}). \item\label{it:vertex:dens} Let $w\in W$. Conditionally on $z_{W\setminus\{w\}}$, the label $z_w$ is uniform on its admissible set $\Phi_w(z_{W\setminus\{w\}})$, which has at least $p2^{-d_w}(1-e_{d_w}(p,n))$ elements; so its conditional density with respect to the uniform probability on $\Fp$ is at most $2^{d_w}/(1-e_{d_w}(p,n))$. If $m$ is a probability measure on $\operatorname{Inj}_p(G)$ whose density with respect to $\lambda$ takes values in an interval $[c,Rc]$, $c>0$, then under $m$ the conditional probability of each value of $z_w$ given $z_{W\setminus\{w\}}$ is at most $R/|\Phi_w|$. \item\label{it:vertex:del} The marginal of $\lambda$ on $W\setminus\{w\}$ is supported on $\operatorname{Inj}_p(G-w)$, and its density with respect to $\lambda_p(G-w)$ takes values in $[R_{\{w\}}^{-1},R_{\{w\}}]$. \item\label{it:vertex:subset} Let $J\subseteq W$. The marginal $\lambda_J$ of $\lambda$ on $J$ is supported on $\operatorname{Inj}_p(G[J])$, and its density with respect to $\lambda_p(G[J])$ takes values in an interval $[c',R_{W\setminus J}c']$, $c'>0$ (in particular in $[R_{W\setminus J}^{-1},R_{W\setminus J}]$). For $m$ as in \ref{it:vertex:dens}, the density of the marginal $m_J$ with respect to $\lambda_p(G[J])$ takes values in an interval $[c'',R\,R_{W\setminus J}c'']$. \item\label{it:vertex:tuple} Let $W=V\sqcup C\sqcup U$ with $V\ne\emptyset$, let $x_C$ be a feasible labelling of $C$, order $V$, and let $t_i$ be the number of neighbours of the $i$-th vertex of $V$ in $C$ and among the earlier vertices of $V$, so that $t_V=\sum_it_i$ is the number of edges inside $V$ or between $V$ and $C$. The conditional law of $z_V$ given $z_C=x_C$ is supported on injective tuples, and its density with respect to the uniform probability on $\Fp^V$ is at most \[ \frac{2^{t_V}R_U}{\prod_i(1-e_{t_i}(p,n))}\ \le\ \frac{2^{t_V}R_U}{(1-e_\Delta(p,n))^{|V|}} . \] \end{enumerate} \end{lemma} \begin{proof} \ref{it:vertex:inv} is \cref{lem:marginals}, parts (1) and (2): the map $z\mapsto\alpha z+\beta$ is a bijection of $\operatorname{Inj}_p(G)$. \ref{it:vertex:dens} For fixed $z_{W\setminus\{w\}}=y'$ the elements of $\operatorname{Inj}_p(G)$ extending $y'$ correspond to the admissible values of $z_w$, all equally likely under $\lambda$. They form a set $\Phi$ of \cref{lem:extension} whose roots are the $d_w$ (distinct) labels of the neighbours of $w$ and whose excluded set consists of the other $|W|-1\le n$ labels, so \cref{lem:extension}\ref{it:ext:coarse} gives the lower bound. Under $m$ the conditional probability of $a\in\Phi_w$ is $(dm/d\lambda)(y',a)/\sum_{a'\in\Phi_w}(dm/d\lambda)(y',a')\le Rc/(|\Phi_w|c)$. \ref{it:vertex:subset} The marginal of $\lambda$ at $x\in\Fp^J$ is $C(x)/|\operatorname{Inj}_p(G)|$, $C(x)$ the number of completions. By \cref{lem:graphs:sequential}\ref{it:seq:count},\ref{it:seq:coarse} for the anchors $J$ and any ordering of $W\setminus J$, whose numbers $t_i$ of earlier neighbours satisfy $t_i\le d_i$, $C$ is positive exactly on $\operatorname{Inj}_p(G[J])$ and takes values in an interval whose endpoints have ratio at most $\prod(1+e_{t_i})/(1-e_{t_i})\le R_{W\setminus J}$ (by \ref{it:et:poly}). The density with respect to the uniform law on $\operatorname{Inj}_p(G[J])$ is proportional to $C$. For $m$, $m_J(x)$ is the sum of $m$ over the completions of $x$, which lies between $cC(x)/|\operatorname{Inj}_p(G)|$ and $RcC(x)/|\operatorname{Inj}_p(G)|$. \ref{it:vertex:del} is \ref{it:vertex:subset} with $J=W\setminus\{w\}$. \ref{it:vertex:tuple} The conditional probability of $x_V$ is $C(x_C,x_V)/\sum_{x'_V}C(x_C,x'_V)$, where $C(x_C,x_V)$ is the number of completions of $(x_C,x_V)$ on $U$. By \cref{lem:graphs:sequential}\ref{it:seq:count} with the anchors $C\cup V$, this count is positive exactly when $(x_C,x_V)\in\operatorname{Inj}_p(G[C\cup V])$, and it takes values in an interval with endpoint ratio at most $R_U$; so the admissible tuples are injective, and the conditional probability of each is at most $R_U$ divided by their number. Since $x_C$ is feasible, $x_C\in\operatorname{Inj}_p(G[C])$, and \cref{lem:graphs:sequential}\ref{it:seq:count} for $G[C\cup V]$ with the anchors $x_C$ and the given ordering of $V$ shows that there are at least $p^{|V|}2^{-t_V}\prod_i(1-e_{t_i}(p,n))$ admissible tuples. Multiplying by $p^{|V|}$ gives the bound, and the last inequality is \ref{it:et:poly} with $t_i\le\Delta$. \end{proof} For a block $\Blk$ all these statements hold at each prime of $\Blk$, and the corresponding statements for $\lambda_{\Blk}(G)$ follow because its marginals, conditional laws and densities are products over the primes of $\Blk$. \subsection{Comparing two graph laws: a ratio of four counts}\label{subsec:labellings:four-count} In Part~V (\cref{lem:front12:reference,lem:upper-reference-rp}) the conditional laws given a middle label (the rows of the middle and upper references) of two graph laws whose graphs differ only away from the conditioned and queried vertices are compared. Their density is then a ratio of four completion counts, whose main terms cancel. \begin{lemma}[Four-count comparison]\label{lem:four-count} Let $G$ and $G'$ be oriented graphs with vertex sets $W$ and $W'$, and let $M,S$ be disjoint subsets of $W\cap W'$ such that $G[M\cup S]=G'[M\cup S]$ (the same edges with the same orientations). Fix orderings and one-step error pairs for which \cref{lem:graphs:sequential} applies to $G$ with the anchors $M$ and with the anchors $M\cup S$, and to $G'$ with the same anchors, and write $\mathrm{up}_G(A),\mathrm{lo}_G(A)$, $\mathrm{up}_{G'}(A),\mathrm{lo}_{G'}(A)$ for the logarithmic count errors with the anchors $A$; write $C_G^A(x_A)$ for the number of elements of $\operatorname{Inj}_p(G)$ extending $x_A$, so that $C_G^\emptyset=|\operatorname{Inj}_p(G)|$. Let $\lambda=\lambda_p(G)$ and $\lambda'=\lambda_p(G')$. \begin{enumerate}[label=\textup{(\alph*)}] \item\label{it:four:formula} For every $x_M\in\operatorname{Inj}_p(G[M])$, the conditional laws of $z_S$ given $z_M=x_M$ under $\lambda$ and under $\lambda'$ are both supported on $\Sigma(x_M)=\{x_S:(x_M,x_S)\in\operatorname{Inj}_p(G[M\cup S])\}$, and the density of the first with respect to the second is \[ \varrho(x_M,x_S)=\frac{C_G^{M\cup S}(x_M,x_S)\,C_{G'}^M(x_M)} {C_G^M(x_M)\,C_{G'}^{M\cup S}(x_M,x_S)} . \] \item\label{it:four:errors} The main terms cancel, and \begin{align*} \log\varrho&\le\mathrm{up}_G(M\cup S)+\mathrm{lo}_G(M)+\mathrm{lo}_{G'}(M\cup S) +\mathrm{up}_{G'}(M),\\ -\log\varrho&\le\mathrm{lo}_G(M\cup S)+\mathrm{up}_G(M)+\mathrm{up}_{G'}(M\cup S) +\mathrm{lo}_{G'}(M). \end{align*} With $M=\emptyset$ this compares the marginals of $\lambda$ and $\lambda'$ on $S$. \item\label{it:four:block} For a block $\Blk$, the density of the conditional law of $z_S$ given $z_M$ under $\lambda_{\Blk}(G)$ with respect to that under $\lambda_{\Blk}(G')$ is the product over $p\in\Blk$ of the densities of \ref{it:four:formula}, and its logarithm lies in the sum over $p\in\Blk$ of the intervals of \ref{it:four:errors}. \end{enumerate} \end{lemma} \begin{proof} \ref{it:four:formula} Under $\lambda$ the law of $z_{M\cup S}$ is $C_G^{M\cup S}/|\operatorname{Inj}_p(G)|$ and that of $z_M$ is $C_G^M/|\operatorname{Inj}_p(G)|$, so the conditional law of $z_S$ given $z_M=x_M$ is $C_G^{M\cup S}(x_M,\cdot)/C_G^M(x_M)$. By \cref{lem:graphs:sequential}\ref{it:seq:count} it is positive exactly on $\Sigma(x_M)$. The same holds for $G'$, with the same set $\Sigma(x_M)$ because $G'[M\cup S]=G[M\cup S]$, and the ratio is $\varrho$. \ref{it:four:errors} For a graph $H$ with vertex set $W_H$ write $\mathrm{main}_H(A)=p^{|W_H|-|A|}2^{-(|E(H)|-|E(H[A])|)}$ for the main term of \cref{lem:graphs:sequential}. In the quotient of the four main terms of $\varrho$ the powers of $p$ cancel, and the powers of $2$ combine to $2^{|E(G[M\cup S])|-|E(G[M])|-|E(G'[M\cup S])|+|E(G'[M])|}=1$, since $G$ and $G'$ have the same induced graphs on $M\cup S$ and on $M$. By \cref{lem:graphs:sequential}\ref{it:seq:count} each count $C_H^A$ lies in $\mathrm{main}_H(A)\,[e^{-\mathrm{lo}_H(A)},e^{\mathrm{up}_H(A)}]$; inserting these four intervals gives the bounds. \ref{it:four:block} The labels at different primes are independent under both product laws, so the conditional laws and their density are products. \end{proof} In Part~V the lemma is applied to the field graphs $G_F$ and $G_E$ of a fold record and of a matching record on three objects (the fold and matching patterns of \cref{def:patterns}), whose induced graphs on any two adjacent objects coincide (\cref{lem:layer12-geometry}(d) in the middle range, \cref{lem:upper-geometry}(d) in the upper range): on two adjacent objects the fold relation and the matching relation both relate every pair of distinct object values and neither has a forward pair. With $M$ the middle object and $S$ one of the outer objects, part \ref{it:four:formula} writes the density of the conditional outer marginals of the rows as a ratio of completion counts, and part \ref{it:four:errors} bounds its logarithm: in the middle range the counts are exact (\cref{lem:record:class-three}(iii)), and in the upper range part \ref{it:four:errors} with the graded insertion counts gives the pointwise marginal ratio of the rows \ref{it:record:upper-F5}. With $M=\emptyset$ and $S$ the middle object, part \ref{it:four:errors} bounds the density of the middle marginals at first order. On a block whose primes are at least $b$ and whose logarithmic length $\sum\log p$ is at most $L$ (any such bound; $L=570$ in the construction), the errors, which are nondecreasing in $r$ by \cref{lem:graphs:sequential}\ref{it:seq:thresholds}, add over at most $L/\log b$ primes by part \ref{it:four:block}. \subsection{How uniform is one label, or a queried pair, given the others?}\label{subsec:labellings:trace} The mixing hypothesis (R4) of \cref{hyp:record:reference} needs, at large primes, that conditioning on all other slots leaves the maximal correlation of one slot, or of a queried pair of slots, with the rest small (\cref{def:mixing}). For a graph law this follows from the symmetry of $\lambda_p(G)$ alone: the operator $T^*T$ commutes with translations and with square dilations, so it is diagonal, or block diagonal, in the additive characters with equal traces along the dilation orbits, and its trace is an average of reciprocal counts. \begin{lemma}[Trace lemma for conditional mixing]\label{lem:trace-mixing} Let $G=(W,E)$ be an oriented graph with $n=|W|\ge3$ vertices and maximum degree $\Delta$, let $p$ be an odd prime with $\operatorname{Inj}_p(G)\ne\emptyset$, and let $\lambda=\lambda_p(G)$. \begin{enumerate}[label=\textup{(\alph*)}] \item\label{it:trace:slot} \emph{One slot.} Let $v\in W$, $d=\deg_G(v)$, and let $w<1$ with $w\ge e_d(p,n-1)$ (for instance $w=w_\Delta(p,n)$ if this is below one). The conditional operator $T=T^{\lambda,v}$ of \cref{def:mixing} satisfies, for every $f\colon\Fp\to\C$ with $\E f=0$, \[ \|Tf\|^2\le\frac2{p-1}\Bigl(\frac{2^d}{1-w}-1\Bigr)\|f\|^2 . \] \item\label{it:trace:pair} \emph{A pair, trace form.} Let $(u,v)\in E$ and $W'=W\setminus\{u,v\}$. The pair $(z_u,z_v)$ has law $\Unif(\Om)$. For a labelling $z'$ of $W'$ in the support of the marginal of $\lambda$, let $\Phi(z')\subseteq\Om$ be the set of pairs $(x,x')$ such that $z'$ together with $z_u=x$, $z_v=x'$ lies in $\operatorname{Inj}_p(G)$; for $y\in\Qsq$ let $c_y(z')$ be the number of $x$ with $(x,x+y)\in\Phi(z')$, and put $\varphi_y(z')=\frac{p-1}2\,c_y(z')/|\Phi(z')|-1$. The conditional operator $(T_{uv}f)(z')=\E_\lambda[f(z_u,z_v)\mid z_{W'}=z']$ satisfies, for every $f\in L^2(\Unif(\Om))$ with mean zero, \[ \|T_{uv}f\|^2\le\max\Bigl\{\E_\lambda\Bigl[\frac2{p-1}\sum_{y\in\Qsq}\varphi_y^2\Bigr],\ p\,\E_\lambda\Bigl[\frac1{|\Phi|}\Bigr]\Bigr\}\|f\|^2 . \] \item\label{it:trace:explicit} \emph{A pair, explicit form.} In \ref{it:trace:pair} let $d'_u=\deg_G(u)-1$, $d'_v=\deg_G(v)-1$, $t=d'_u+d'_v$, $s=\max(d'_u,d'_v)$, $n_\times=d'_ud'_v$, and let $e<1$ with $e\ge e_t(p,2n-4)$ and $e\ge e_{s+1}(p,n)$. Put \[ \eta=\frac{n_\times2^{t-s+1}}{p-1},\qquad \varphi_{\rm gen}=\frac{3e}{(1-e)^2}+(1+e)\eta,\qquad \varphi_{\rm exc}=\frac{2^{t-s}(1+e)}{(1-e)^2} . \] Then for every mean-zero $f\in L^2(\Unif(\Om))$, \[ \|T_{uv}f\|^2\le\max\Bigl\{\varphi_{\rm gen}^2+\frac{2n_\times}{p-1}\varphi_{\rm exc}^2,\ \frac{2^{t+1}}{(p-1)(1-e)^2}\Bigr\}\|f\|^2 . \] \item\label{it:trace:72} \emph{Seventy-two vertices of degree at most twenty.} If $n=72$ and $\Delta\le20$, then for every prime $p\ge2^{512}$, every vertex $v$ and every edge $(u,v)$, the squared norms in \ref{it:trace:slot} and \ref{it:trace:pair} on the mean-zero functions are at most $2^{22}/p$ and $2^{92}/p$ respectively. \end{enumerate} \end{lemma} \begin{proof} Let $\mathfrak G$ be the group of the maps $x\mapsto\alpha x+\beta$ ($\alpha\in\Qsq$, $\beta\in\Fp$), acting on labellings coordinatewise. It preserves $\operatorname{Inj}_p(G)$ (it multiplies every difference by a nonzero square), hence $\lambda$ and all its marginals (\cref{lem:marginals}); its translations act transitively on $\Fp$, and $\mathfrak G$ acts transitively on $\Om$ (\cref{lem:marginals}, part (3)), so the one-slot marginals are uniform and, the edge $(u,v)$ forcing $(z_u,z_v)\in\Om$, the pair has law $\Unif(\Om)$. \ref{it:trace:slot} For a labelling $z'$ of $W\setminus\{v\}$ in the support of the marginal $\lambda'$, let $\Phi_v(z')$ be the set of admissible labels of $v$; since $\lambda$ is uniform, $Tf(z')=|\Phi_v(z')|^{-1}\sum_{x\in\Phi_v(z')}f(x)$. The labels of the $d$ neighbours of $v$ are distinct and lie among the $n-1$ excluded labels, so \cref{lem:extension}\ref{it:ext:coarse} gives $|\Phi_v(z')|\ge p2^{-d}(1-e_d(p,n-1))\ge p2^{-d}(1-w)$. For $g\in\mathfrak G$, $\Phi_v(gz')=g\Phi_v(z')$, hence $T(f\circ g)=(Tf)\circ g$; the maps $f\mapsto f\circ g$ are unitary on $L^2(\Fp)$ and on $L^2(\lambda')$, so $S=T^*T$ commutes with them. Commuting with the translations, $S$ is diagonal in the characters $e_\xi(x)=e(\xi x/p)$, each of which spans the joint eigenspace of the translations for its own character: $Se_\xi=\kappa_\xi e_\xi$ with $\kappa_\xi=\|Te_\xi\|^2\ge0$. Since $e_\xi(\alpha x)=e_{\alpha\xi}(x)$, commuting with the dilations gives $\kappa_{\alpha\xi}=\kappa_\xi$ for $\alpha\in\Qsq$: $\kappa$ takes one value $\kappa_+$ on $\Qsq$ and one value $\kappa_-$ on the nonsquares, and $\kappa_0=\|T\one\|^2=1$. In the orthonormal basis $(\sqrt p\,\one_{\{x\}})_x$, \[ \tr S=\sum_xp\,\|T\one_{\{x\}}\|^2 =\sum_xp\,\E_{\lambda'}\Bigl[\frac{\one\{x\in\Phi_v\}}{|\Phi_v|^2}\Bigr] =p\,\E_{\lambda'}\Bigl[\frac1{|\Phi_v|}\Bigr]\le\frac{2^d}{1-w}, \] and $\tr S=1+\frac{p-1}2(\kappa_++\kappa_-)$. Hence $\max(\kappa_+,\kappa_-)\le\frac2{p-1}\bigl(\frac{2^d}{1-w}-1\bigr)$, and for $f=\sum_{\xi\ne0}\widehat f(\xi)e_\xi$, $\|Tf\|^2=\sum_{\xi\ne0}\kappa_\xi|\widehat f(\xi)|^2\le\max(\kappa_+,\kappa_-)\|f\|^2$. Finally $e_d(p,n-1)\le e_\Delta(p,n)\le w_\Delta(p,n)$ by \ref{it:et:compare}, \ref{it:et:poly}. \ref{it:trace:pair} Use the coordinates $(x,y)$, $x'=x+y$, which identify $\Om$ with $\Fp\times\Qsq$ and $\Unif(\Om)$ with the uniform law there; write $\E_y$ for the average over $y\in\Qsq$ and $\lambda''$ for the marginal of $z_{W'}$. Since $\lambda$ is uniform, $T_{uv}f(z')=|\Phi(z')|^{-1}\sum_{\omega\in\Phi(z')}f(\omega)$, and as in \ref{it:trace:slot}, $\Phi(gz')=g\Phi(z')$ for $g\in\mathfrak G$ (acting diagonally on $\Om$), so $S=T_{uv}^*T_{uv}$ commutes with the unitaries $f\mapsto f\circ g$. The translation $x\mapsto x+\beta$ acts by $(x,y)\mapsto(x+\beta,y)$ and the dilation by $\alpha\in\Qsq$ by $(x,y)\mapsto(\alpha x,\alpha y)$. For $k\in\Fp$ let $\mathcal H_k=\{e_k(x)\psi(y)\}$; these spaces are orthogonal, they are the joint eigenspaces of the translations (with distinct characters), and $L^2_0(\Unif(\Om))=(\mathcal H_0\ominus\C\one)\oplus\bigoplus_{k\ne0}\mathcal H_k$. So $S$ preserves each $\mathcal H_k$, and also $\mathcal H_0\ominus\C\one$ (it fixes $\one$ and is self-adjoint), and $\|T_{uv}|_{L^2_0}\|^2$ is the largest of the norms of the restrictions $S_k$ of $S$ to $\mathcal H_k$ ($k\ne0$) and to $\mathcal H_0\ominus\C\one$. \emph{Nonzero frequencies.} The dilation by $\alpha$ maps $\mathcal H_k$ onto $\mathcal H_{\alpha k}$ and commutes with $S$, so $\tr S_k$ takes one value $\sigma_+$ for $k\in\Qsq$ and one value $\sigma_-$ for the nonsquares. Since $S_k\succeq0$, $\|S_k\|\le\tr S_k$, and $\frac{p-1}2(\sigma_++\sigma_-)\le\tr S$. In the orthonormal basis $(|\Om|^{1/2}\one_{\{\omega\}})_\omega$, as in \ref{it:trace:slot}, $\tr S=|\Om|\,\E_{\lambda''}[1/|\Phi|]$. With $|\Om|=p(p-1)/2$ this gives $\|S_k\|\le\sigma_++\sigma_-\le p\,\E[1/|\Phi|]$. \emph{Frequency zero.} For $\psi\in\mathcal H_0$ with $\E_y\psi=0$, \[ T_{uv}\psi(z')=\sum_{y\in\Qsq}\frac{c_y(z')}{|\Phi(z')|}\psi(y) =\E_y\bigl[(1+\varphi_y(z'))\psi(y)\bigr]=\E_y\bigl[\varphi_y(z')\psi(y)\bigr], \] so by Cauchy--Schwarz $|T_{uv}\psi(z')|^2\le\E_y[\varphi_y(z')^2]\,\E_y|\psi|^2$, and $\|T_{uv}\psi\|^2\le\E_{\lambda''}\bigl[\frac2{p-1}\sum_y\varphi_y^2\bigr]\|\psi\|^2$. \ref{it:trace:explicit} Fix $z'$ in the support; let $\mathcal L=z'(W')$, a set of $n-2$ labels, and let $B_u$, $B_v$ be the sets of labels of the neighbours of $u$, respectively $v$, in $W'$; $|B_u|=d'_u$, $|B_v|=d'_v$. A pair $(x,x+y)$ lies in $\Phi(z')$ iff $x,x+y\notin\mathcal L$ and $x$ satisfies the $d'_u$ conditions $\chi(x-\beta)=s_\beta$ ($\beta\in B_u$) from the edges at $u$ and the $d'_v$ conditions $\chi(x-(\beta'-y))=s'_{\beta'}$ ($\beta'\in B_v$) from the edges at $v$; the edge $(u,v)$ is the condition $y\in\Qsq$. So $c_y$ is the size of a set $\Phi$ of \cref{lem:extension} with excluded set $\mathcal L\cup(\mathcal L-y)$, of size at most $2n-4$, which contains all the roots. Call $y$ \emph{generic} if $B_u\cap(B_v-y)=\emptyset$; at most $n_\times$ values of $y$ are not. \emph{Counts.} For generic $y$ there are $t$ distinct roots, and \cref{lem:extension}\ref{it:ext:coarse} gives $c_y\in p2^{-t}[1-e,1+e]$. For every $y$, keeping only the conditions of an endpoint with $s$ conditions, \cref{lem:extension}\ref{it:ext:upper} gives $c_y\le p2^{-s}(1+e^+_s)\le p2^{-s}(1+e)$, since $e^+_s\le e_s(p,n)\le e_{s+1}(p,n)\le e$. Labelling first the endpoint with $s$ conditions and then the other endpoint, which has $t-s+1\le s+1$ conditions (its own and the edge $(u,v)$), \cref{lem:graphs:sequential}\ref{it:seq:count} with the coarse pair gives $|\Phi(z')|\ge p^22^{-(t+1)}(1-e)^2$. \emph{Bounds.} Hence $p\,\E[1/|\Phi|]\le2^{t+1}/(p(1-e)^2)$, which is at most the second term. Recall $|\Qsq|=\frac{p-1}2$. For generic $y$, $|\Qsq|c_y/|\Phi|\le|\Qsq|p2^{-t}(1+e)/(p^22^{-(t+1)}(1-e)^2)\le(1+e)/(1-e)^2$, so $\varphi_y\le3e/(1-e)^2$; and $|\Phi|=\sum_yc_y\le|\Qsq|p2^{-t}(1+e)+n_\times p2^{-s}(1+e)=|\Qsq|p2^{-t}(1+e)(1+\eta)$, so $|\Qsq|c_y/|\Phi|\ge(1-e)/((1+e)(1+\eta))$ and \[ -\varphi_y\le\frac{2e+(1+e)\eta}{(1+e)(1+\eta)}\le2e+(1+e)\eta . \] Thus $|\varphi_y|\le\varphi_{\rm gen}$ for generic $y$. For the other $y$, $-1\le\varphi_y\le|\Qsq|p2^{-s}(1+e)/(p^22^{-(t+1)}(1-e)^2)\le\varphi_{\rm exc}$, and $\varphi_{\rm exc}\ge1$, so $|\varphi_y|\le\varphi_{\rm exc}$. Therefore $\frac2{p-1}\sum_y\varphi_y^2\le\varphi_{\rm gen}^2+\frac{2n_\times}{p-1}\varphi_{\rm exc}^2$, and \ref{it:trace:explicit} follows from \ref{it:trace:pair}. \ref{it:trace:72} In \ref{it:trace:slot} take $w=w_{20}(p,72)=2^{20}(10r+72r^2)$, which is at least $e_d(p,71)$ for $d\le20$ by \ref{it:et:compare}, \ref{it:et:poly}; the bound is nondecreasing in $d$, so $d=20$ is the worst case. In \ref{it:trace:explicit} take $e=e_{38}(p,140)=2^{38}((18+2^{-38})r+140r^2)$, which is at least $e_t(p,140)$ and $e_{s+1}(p,72)$ since $t\le38$ and $s+1\le20$; the right side of \ref{it:trace:explicit} is nondecreasing in $n_\times\le361$, $t-s\le19$ and $t+1\le39$, so the worst case is $d'_u=d'_v=19$, with $\eta=361\cdot2^{20}/(p-1)$ and $\varphi_{\rm exc}=2^{19}(1+e)/(1-e)^2$. Multiplied by $p$, the three resulting expressions are \[ \frac2{1-r^2}\Bigl(\frac{2^{20}}{1-w}-1\Bigr),\qquad \Bigl(\frac{\varphi_{\rm gen}}r\Bigr)^2+\frac{722\,\varphi_{\rm exc}^2}{1-r^2},\qquad \frac{2^{39}}{(1-r^2)(1-e)^2}, \] and $e/r$, $w/r$ and $\eta/r=361\cdot2^{20}r/(1-r^2)$ are nondecreasing in $r$; so all three are nondecreasing in $r$ (\cref{lem:majorant}), and it suffices to bound them at $p=2^{512}$, which \cref{cert:trace-mixing-72} does. \end{proof} \begin{certificate}[Mixing constants of the two-layer root at $p=2^{512}$] \label{cert:trace-mixing-72} At $p=2^{512}$, the quantities $e=e_{38}(p,140)$, $\eta=361\cdot2^{20}/(p-1)$, $\varphi_{\rm gen}=3e/(1-e)^2+(1+e)\eta$, $\varphi_{\rm exc}=2^{19}(1+e)/(1-e)^2$ and $w=2^{20}(10p^{-1/2}+72p^{-1})$ of the proof of \cref{lem:trace-mixing}\ref{it:trace:72} satisfy $e<\frac12$, $w<\frac12$ and the three inequalities below. They are evaluated in exact rational arithmetic by the function \texttt{leading\_trace} of \path{research/push_2026_10_17/structural/layer72_analytic.py}: \[ p\Bigl(\varphi_{\rm gen}^2+\frac{722}{p-1}\varphi_{\rm exc}^2\Bigr)<2^{92},\qquad \frac{p\,2^{39}}{(p-1)(1-e)^2}<2^{92},\qquad \frac{2p}{p-1}\Bigl(\frac{2^{20}}{1-w}-1\Bigr)<2^{22} . \] For orientation only (not part of the check), the three left sides are approximately $2^{87.51}$, $2^{39}$ and $2^{21}$. How the check is run and authenticated is recorded in its row of \cref{tab:cert:finite}. \end{certificate} \subsection{Primes \texorpdfstring{$p\equiv3\pmod4$}{p = 3 (mod 4)}: the Paley tournament, triples, and operators}\label{subsec:labellings:class-three} At a prime $p\equiv3\pmod4$, $-1$ is a nonsquare, so for $x\ne y$ exactly one of $y-x$ and $x-y$ is a square: the strict-square relation is a tournament, the Paley tournament, and the character kernel $\chi(t-s)$ is antisymmetric. This is why the middle and upper primes are taken with $p\equiv3\pmod4$: the laws of directed configurations there have exact counts and exact correlation identities, which the following lemma collects. (At $p\equiv1\pmod4$ the relation is symmetric and the tournament statements of the lemma fail; its part \ref{it:paley:corr} holds for every odd $p$, and the disjoint-triple operator at the end of the subsection uses no character sum and is treated at every prime $p\ge7$.) \begin{lemma}[Paley-triple calculus]\label{lem:paley-triple} Let $p\equiv3\pmod4$ be prime and write $a\to b$ if $\chi(b-a)=1$. Put $k=(p-3)/4$ and let $P$ be the Paley operator of \cref{lem:square-shift}, $(Ph)(s)=\E_t\chi(t-s)h(t)$ on $L^2(\Fp)$. \begin{enumerate}[label=\textup{(\alph*)}] \item\label{it:paley:counts} \emph{Tournament counts.} $\to$ is a tournament on $\Fp$ in which every label has $(p-1)/2$ out-neighbours and $(p-1)/2$ in-neighbours. Two distinct labels $a\ne a'$ have exactly $k$ common out-neighbours and exactly $k$ common in-neighbours, and $\#\{c:a\to c\to a'\}=k+1-\one[a\to a']$. \item\label{it:paley:corr} \emph{Character correlations.} $\E_t\chi(t-a)\chi(t-a')=\one[a=a']-q$ for all $a,a'\in\Fp$ (for every odd $p$; this is \eqref{eq:two-root}). \item\label{it:paley:op} \emph{The Paley operator.} $P^*=-P$, $P\one=0$, $P^*P=PP^*=q(I-\Jproj)$ and $\|P\|=r$ (\cref{lem:square-shift}(c)). Hence $P$ maps $H_0$ into itself, and on $H_0$ we have $P^2=-qI$, i.e.\ $pP^2=-I$, and $P/r$ is unitary with eigenvalues $\pm i$. \item\label{it:paley:triples} \emph{Directed triples.} Let $\nu_F$ be the uniform law on $H_F=\{(x_0,x_1,x_2):\ x_0,x_1,x_2\ \text{distinct},\ x_0\to x_2\}$, and $V_i\colon L^2(\Fp)\to L^2(\nu_F)$, $(V_ih)(x)=h(x_i)$. The coordinates of $\nu_F$ are uniform, each $V_i$ is an isometry, and $V_i^*$ is the conditional expectation onto $x_i$. On $H_0$, \[ V_0^*V_2=\frac{P-qI}{1-q},\qquad V_0^*V_1=V_1^*V_2=-\frac{I+V_0^*V_2}{p-2}=-\frac I{p-1}-\frac{pP}{(p-1)(p-2)}, \] and so $V_2^*V_0=-(P+qI)/(1-q)$ and $V_1^*V_0=V_2^*V_1=-\frac I{p-1}+\frac{pP}{(p-1)(p-2)}$. The norms on $H_0$ are exactly \[ \|V_0^*V_2\|=\varrho:=\frac{r\sqrt{1+q}}{1-q}=\frac{\sqrt{p+1}}{p-1},\qquad \|V_0^*V_1\|=\|V_1^*V_2\|=\varrho_1:=\frac{q}{1-q}\sqrt{1+\frac q{(1-2q)^2}}, \] and $\varrho_1\le\varrho':=q(1+\varrho)/(1-2q)$. For $p\ge7$, $\varrho'\le\varrho$, and the Gram operator $(V_i^*V_j)_{i,j}$ of $(V_0,V_1,V_2)$ on $H_0^3$ has norm at most $\Gamma:=1+\varrho+\varrho'$. \item\label{it:paley:features} \emph{Features.} Let $A_1=V_2P$, $A_2=V_1P$ and $(A_3h)(x)=-\E_s[\chi(s-x_2)\chi(s-x_1)h(s)]-q\,\E h$, operators $L^2(\Fp)\to L^2(\nu_F)$. Each $A_j$ annihilates the constants and maps into the $\nu_F$-mean-zero functions, and on $H_0$ \begin{gather*} A_1^*A_1=A_2^*A_2=qI,\qquad A_3^*A_3=\frac{1-2q-q^2}{p-1}I\preceq qI,\qquad A_1^*A_2=-\frac q{p-1}I+\frac P{(p-1)(p-2)},\\ A_1^*A_3=-\frac q{(p-1)(p-2)}I+\frac q{p-1}P,\qquad A_2^*A_3=\frac q{(p-1)(p-2)}I+\frac q{p-1}P,\\ V_1^*A_3=-\frac q{p-1}I+\frac P{(p-1)(p-2)},\qquad V_2^*A_3=-\frac q{p-1}I-\frac P{(p-1)(p-2)},\\ V_0^*A_1=-\frac{I+P}{p-1},\qquad V_0^*A_2=\frac I{(p-1)(p-2)}-\frac P{p-1},\qquad V_0^*A_3=\frac{2I}{p(p-1)(p-2)} . \end{gather*} Hence, for $\xi\in\R^3$ and $A_\xi=\xi_1A_1+\xi_2A_2+\xi_3A_3$, $V_0^*A_\xi=a_\xi I+b_\xi P$ on $H_0$ with \[ a_\xi=-\frac{\xi_1q}{1-q}+\frac{\xi_2q^2}{(1-q)(1-2q)}+\frac{2\xi_3q^3}{(1-q)(1-2q)}, \qquad b_\xi=-\frac{(\xi_1+\xi_2)q}{1-q}, \] and $\|(A_1,A_2,A_3)\|\le r\gamma$ on $H_0^3$, with $\gamma^2=1+q(1+2r)/(1-2q)$. \item\label{it:paley:perturb} \emph{Density perturbation.} Let $m=g\nu_F$ be a probability measure on $H_F$ with uniform coordinate marginals and $|g-1|\le e$. Then $|\ip FG_m-\ip FG_{\nu_F}|\le e\|F\|_{\nu_F}\|G\|_{\nu_F}$ and $(1-e)\|F\|^2_{\nu_F}\le\|F\|_m^2\le(1+e)\|F\|^2_{\nu_F}$ for all $F,G$. In particular, for $f,h\in H_0$ the correlations $\ip{V_if}{V_jh}$ under $m$ and under $\nu_F$ differ by at most $e\|f\|\|h\|$, the norms $\|V_if\|$ being equal under both laws; and for every operator $A\colon L^2(\Fp)\to L^2(\nu_F)$, the adjoints of $V_i$ in $L^2(m)$ and in $L^2(\nu_F)$ satisfy $\|V_{i,m}^*A-V_{i,\nu_F}^*A\|\le e\|A\|$. \end{enumerate} \end{lemma} \begin{proof} \ref{it:paley:corr} is \eqref{eq:two-root}. \ref{it:paley:counts} Since $\chi(-1)=-1$, $\chi(a-b)=-\chi(b-a)$, so exactly one of $a\to b$, $b\to a$ holds for $a\ne b$; out- and in-neighbours of $a$ are the $(p-1)/2$ labels $b$ with $\chi(b-a)=1$, respectively $-1$. For $a\ne a'$, \[ 4\#\{c:a\to c,\ a'\to c\}=\sum_{c\ne a,a'}(1+\chi(c-a))(1+\chi(c-a')) =(p-2)-\chi(a'-a)-\chi(a-a')-1=p-3, \] using $\sum_{c\ne a}\chi(c-a)=0$ and \eqref{eq:two-root}; the in-neighbours are the same computation with $1-\chi$, and give $p-3$ again. For the paths, $4\#\{c\}=\sum_{c\ne a,a'}(1+\chi(c-a))(1+\chi(a'-c))=(p-2)-2\chi(a'-a)+1$, because both linear sums equal $-\chi(a'-a)$ and $\sum_c\chi(c-a)\chi(a'-c)=-\sum_c\chi((c-a)(c-a'))=1$; this is $4k$ if $a\to a'$ and $4k+4$ otherwise. \ref{it:paley:op} The first assertions are \cref{lem:square-shift}(c), since $\chi(-1)=-1$. As $P^*\one=-P\one=0$, $P$ maps $H_0$ into itself; there $P^*P=PP^*=qI$, so $P/r$ is unitary, and $P^2=-P^*P=-qI$, so its eigenvalues are $\pm i$. \ref{it:paley:triples} The translations preserve $H_F$ and act transitively on each coordinate, so the coordinates are uniform, $V_i$ is an isometry, and $\ip{V_ih}F_{\nu_F}=\E_s\overline{h(s)}\,\E_{\nu_F}[F\mid x_i=s]$. Given $x_0=s$, the label $x_2$ is uniform on the set $s+\Qsq$ of the out-neighbours of $s$, and given $(x_0,x_2)$ the label $x_1$ is uniform on the other $p-2$ labels. So $V_0^*V_2$ is the square shift $T_p$ of \cref{lem:square-shift}, which is $(p\Jproj-I+pP)/(p-1)$ by part (c) there, that is $(pP-I)/(p-1)$ on $H_0$; and for $g\in H_0$, $\E[g(x_1)\mid x_0,x_2]=-(g(x_0)+g(x_2))/(p-2)$, which gives $V_0^*V_1$; conditioning on $x_2$ instead gives $V_2^*V_1=-(I+V_2^*V_0)/(p-2)$, whose adjoint is $V_1^*V_2$. The closed forms follow from $q/(1-q)=1/(p-1)$, and the adjoints from $P^*=-P$. By \ref{it:paley:op}, $P$ is normal on $H_0$ with eigenvalues $\pm ir$, so $V_0^*V_2$ has eigenvalues $(-q\pm ir)/(1-q)$, of modulus $\varrho$, and $V_0^*V_1$ has eigenvalues $-\frac1{p-1}\mp\frac{ipr}{(p-1)(p-2)}$, of modulus $\frac1{p-1}(1+\frac p{(p-2)^2})^{1/2}=\varrho_1$; and $\varrho_1=\|I+V_0^*V_2\|/(p-2)\le(1+\varrho)/(p-2)=\varrho'$. The inequality $\varrho'\le\varrho$ is $q\le\varrho(1-3q)$, i.e.\ $1\le(p-3)\sqrt{p+1}/(p-1)$, which holds for $p\ge7$. The Schur test applied to the symmetric matrix of the norms of the blocks of the Gram operator bounds its norm by the largest row sum, $1+\max(\varrho+\varrho_1,2\varrho_1)\le\Gamma$. \ref{it:paley:features} By \ref{it:paley:op}, $A_1\one=A_2\one=0$, and $A_3\one=-(\one[x_1=x_2]-q)-q=0$ by \ref{it:paley:corr}. The functions $A_1h$, $A_2h$ have mean $\E Ph=0$, and $\E_{\nu_F}[\chi(s-x_2)\chi(s-x_1)]$ does not depend on $s$ (translation invariance), hence equals its average over $s$, which is $-q$; so $\E_{\nu_F}A_3h=q\E h-q\E h=0$. Let $M_{1|2}=V_2^*V_1$, the conditional expectation of a function of $x_1$ given $x_2$. For distinct $a,b$ the number of $x_0$ with $(x_2,x_1)=(a,b)$ is $(p-2-\chi(a-b))/2$; summing $g(b)$ against these weights gives, on all of $L^2(\Fp)$, \[ M_{1|2}=\frac{p\Jproj-I}{p-1}+\frac{pP}{(p-1)(p-2)},\qquad M_{1|2}^*=V_1^*V_2=\frac{p\Jproj-I}{p-1}-\frac{pP}{(p-1)(p-2)} . \] On $H_0$, where $\Jproj=0$ and $P$ maps $H_0$ into itself, $A_1^*A_1=A_2^*A_2=P^*P=qI$ and $A_1^*A_2=P^*M_{1|2}P=-\frac{P^*P}{p-1}+\frac{pP^*P\,P}{(p-1)(p-2)} =-\frac q{p-1}I+\frac P{(p-1)(p-2)}$, since $pq=1$. For $A_3$ write $\Psi_h(a,b)=\E_s\chi(s-a)\chi(s-b)h(s)$, so $A_3h(x)=-\Psi_h(x_2,x_1)$ on $H_0$, and $\varphi_s(b)=\chi(s-b)$. By \ref{it:paley:corr}, $(P\varphi_s)(a)=q-\one[a=s]$, and $\Jproj\varphi_s=0$, so \[ \E[\chi(s-x_1)\mid x_2=a]=(M_{1|2}\varphi_s)(a) =-\frac{\chi(s-a)}{p-1}-\frac{p\one[a=s]-1}{(p-1)(p-2)} . \] Multiplying by $\chi(s-a)h(s)$ and averaging over $s$, with $\chi(s-a)^2=\one[s\ne a]$ and $\chi(s-a)\one[a=s]=0$, gives $\E[\Psi_h(a,x_1)\mid x_2=a]=\frac q{p-1}h(a)+\frac{Ph(a)}{(p-1)(p-2)}$ for $h\in H_0$, which is $-V_2^*A_3h(a)$. Conditioning on $x_1$ with $M_{1|2}^*$ gives $V_1^*A_3$ in the same way. Then $A_1^*A_3=P^*V_2^*A_3$ and $A_2^*A_3=P^*V_1^*A_3$, and $P^*=-P$, $P^2=-qI$ give the stated values. For $A_3^*A_3$: the law of $(x_2,x_1)$ is $(p-2-\chi(a-b))/(p(p-1)(p-2))$ on distinct pairs, $\Psi_h$ is symmetric and the antisymmetric part $\chi(a-b)$ integrates to zero against $\Psi_{h'}\Psi_h$; with $\E_{a,b}\Psi_{h'}\Psi_h=\E_{s,s'}h'(s)h(s')(\one[s=s']-q)^2 =q(1-2q)\ip{h'}h$ and $\Psi_h(a,a)=-qh(a)$, one gets $\frac p{p-1}\bigl[q(1-2q)-q^3\bigr]\ip{h'}h=\frac{1-2q-q^2}{p-1}\ip{h'}h$, which is at most $q\ip hh$ for $h'=h$. Next $V_0^*A_1=V_0^*V_2P=(P^2-qP)/(1-q)=-(I+P)/(p-1)$ and $V_0^*A_2=V_0^*V_1P=-\frac P{p-1}-\frac{pP^2}{(p-1)(p-2)}$. Finally, given $x_0=s$ and $x_2=a$, $\E[\chi(t-x_1)\mid x_0,x_2]=-(\chi(t-s)+\chi(t-a))/(p-2)$; so \begin{align*} \E\bigl[\chi(t-x_2)\chi(t-x_1)\bigm|x_0=s\bigr] &=-\frac{\chi(t-s)\E[\chi(t-x_2)\mid x_0=s]+\Pr(x_2\ne t\mid x_0=s)}{p-2}\\ &=-\frac{1-2\cdot\one[t\ne s]/(p-1)}{p-2}, \end{align*} by $\E[\chi(t-x_2)\mid x_0=s]=(1-\chi(t-s)-p\one[t=s])/(p-1)$ (the computation of $V_0^*V_2$ applied to $\varphi_t$) and $\Pr(x_2=t\mid x_0=s)=(\one[t\ne s]+\chi(t-s))/(p-1)$. Averaging against $h\in H_0$ gives $V_0^*A_3h=-\E[\Psi_h(x_2,x_1)\mid x_0]=\frac{2q}{(p-1)(p-2)}h$. The formula for $V_0^*A_\xi$ is linearity with $1/(p-1)=q/(1-q)$ and $1/((p-1)(p-2))=q^2/((1-q)(1-2q))$. For the norm, the Schur test applied to the matrix of the norms $\|A_i^*A_j\|$ (with $\|P\|=r$) bounds $\|(A_1,A_2,A_3)\|^2$ by its largest row sum. The first two rows sum to $q+\frac{q^2}{1-q}+\frac{rq^2}{(1-q)(1-2q)}+\frac{q^3}{(1-q)(1-2q)}+\frac{q^2r}{1-q} =q\bigl(1+\frac{q(1+2r)}{1-2q}\bigr)=q\gamma^2$, and the third row is smaller by $\frac{2q^2(1-2q+qr-q^2)}{(1-q)(1-2q)}>0$. \ref{it:paley:perturb} $|\ip FG_m-\ip FG_{\nu_F}|=|\E_{\nu_F}[(g-1)\overline FG]|\le e\,\E_{\nu_F}|F||G|$, and Cauchy--Schwarz gives the first claim; the second is the case $F=G$. The coordinate marginals of $m$ are uniform, so $\|V_if\|_m=\|f\|=\|V_if\|_{\nu_F}$ and the means of $V_if$, $f\in H_0$, vanish under both laws. For the adjoints, $\ip f{(V_{i,m}^*-V_{i,\nu_F}^*)Ah}=\ip{V_if}{Ah}_m-\ip{V_if}{Ah}_{\nu_F}$, which is at most $e\|f\|\|A\|\|h\|$ in modulus. \end{proof} In the middle range these identities enter three times: the counts of \ref{it:paley:counts} make the middle pair law exact (\cref{lem:record:class-three}) and give the actual pair laws of the fold records (\cref{lem:actual-features}); the Grams of \ref{it:paley:triples} give the channel norms of the reference fold record (\cref{lem:old-f-law}) and, with \ref{it:paley:perturb}, the block-extension estimates for the actual features (\cref{lem:oct24:feature-block}); and \ref{it:paley:features} is the Gram-matrix calculus behind the joint bound for the reference and the signed comparison fold records (\cref{lem:record:direct-gram}), with $A_3$ the second-order feature of the comparison record. The matching records of the middle range are uniform on pairs of disjoint injective triples, and at the reserved cut their Markov operator relative to the actual half law is the following operator (the identification is \cref{lem:record:gram}). Its negativity is exact and uses no character sum. \begin{lemma}[The disjoint-triple operator]\label{sec:frontier:empty-triple-negative} Let $p\ge7$, let $\mathcal T$ be the set of ordered triples of distinct elements of $\Fp$ with its uniform law, and let $T$ be the Markov operator on $L^2(\mathcal T)$ which, given a triple $x$, chooses a triple $y\in\mathcal T$ disjoint from $x$ uniformly: $Tf(x)=\frac1{(p-3)(p-4)(p-5)}\sum_{y\cap x=\emptyset}f(y)$. \begin{enumerate}[label=\textup{(\alph*)}] \item\label{it:triple:spec} $T$ is self-adjoint, annihilates the functions whose average over the orderings of each unordered triple vanishes, and on functions of the unordered triple it has the eigenvalues \begin{equation}\label{eq:triple:spectrum} \lambda_j=(-1)^j\binom{p-3-j}{3-j}\Big/\binom{p-3}3\qquad(j=0,1,2,3), \end{equation} that is $1$, $-\frac3{p-3}$, $\frac6{(p-3)(p-4)}$ and $-\frac6{(p-3)(p-4)(p-5)}$, the eigenvalue $1$ having the constants as its eigenspace. \item\label{it:triple:bound} Hence $-\frac3{p-3}I\preceq T\preceq I$, the lower constant is attained, and $\|T-\Jproj\|=\frac3{p-3}$. \item\label{it:triple:block} For a block $\Blk$ of primes with least prime $b\ge7$, the tensor product $T_{\Blk}=\bigotimes_{p\in\Blk}T$ on $L^2$ of the product of the uniform laws satisfies $-\frac3{b-3}I\preceq T_{\Blk}\preceq I$ and $\|T_{\Blk}-\Jproj\|\le\frac3{b-3}$. \end{enumerate} \end{lemma} \begin{proof} \ref{it:triple:spec} The kernel of $T$ with respect to the uniform law is symmetric, so $T$ is self-adjoint, and $T\one=\one$. For $f$ on $\mathcal T$ let $\bar f$ be its average over the six orderings of each triple. Then $Tf(x)=\binom{p-3}3^{-1}\sum_Y\bar f(Y)$, the sum over the unordered triples $Y$ disjoint from $\{x_0,x_1,x_2\}$; so $Tf=0$ if $\bar f=0$, and on the functions of the unordered triple $T$ acts as the operator $\bar T$ on functions of $3$-subsets of $\Fp$ given by the same formula. For $0\le j\le3$ let $\mathcal F_j$ be the space of functions on $j$-subsets, with the counting inner product. Put $(U_jf)(B)=\sum_{x\in B}f(B\setminus\{x\})$ for $f\in\mathcal F_j$ and $|B|=j+1$, and $D_{j+1}=U_j^*$, so $(D_{j+1}g)(A)=\sum_{y\notin A}g(A\cup\{y\})$. Counting the terms that add and remove the same element gives $D_{j+1}U_j-U_{j-1}D_j=(p-2j)I$ on $\mathcal F_j$ ($U_{-1}D_0=0$). For $j\le2

0$ be real and $r_0=p_0^{-1/2}$, with $e_\Delta(p_0,2n)$ denoting the polynomial in $r_0$ of \eqref{eq:graphs:et}. The data satisfy the \emph{threshold hypothesis at $p_0$} if \begin{enumerate}[label=\textup{(S1)},leftmargin=*] \item $e_\Delta(p_0,2n)<1$ and $p_0>4n^2$. \end{enumerate} \end{definition} Since $e_\Delta(\cdot,2n)$ is a polynomial in $r$ with nonnegative coefficients, (S1) at $p_0$ implies (S1) at every prime $p\ge p_0$; this is the simplest instance of the monotone-majorant principle (\cref{lem:majorant}) by which one exact check at a threshold covers all larger primes. The pinned correlations of the half graph $G^+$ are governed by the influence conditions \eqref{eq:spec:S2} of \cref{subsec:cuts:influence}, which are not part of the definition. \begin{lemma}[Elementary facts]\label{lem:spec:elementary} Under \textup{(S0)}: $\varsigma$ is well defined, $\varsigma_{kj}=-\varsigma_{jk}$ and $\varsigma_{kk}=0$; hence $(j,k)\in E_\times$ iff $(k,j)\in E_\times$, and $\#\{k:\varsigma_{jk}\ne0\}=r_j$. The map $(j,k)\mapsto$ (the edge of $G$ between $j$ and $\vartheta k$) is a bijection from $E_\times$ onto the set of cross edges. Every vertex $k\in U^+$ and its image $\vartheta k$ have degree $d_k$ in $G$, so $\Delta$ is the maximum degree of $G$. Finally $\vartheta$ maps $G^+$ isomorphically, with orientations, onto $G[U^-]$. \end{lemma} \begin{proof} $\varsigma_{jk}$ is well defined because $G$ contains at most one of the two opposite directed edges on each unordered pair. Applying $\vartheta$ (an orientation-preserving involution) gives $(k,\vartheta j)\in E$ iff $(\vartheta k,j)\in E$, so $\varsigma_{kj}=+1$ iff $\varsigma_{jk}=-1$, and likewise with the signs exchanged. An edge $(k,\vartheta k)$ would give the opposite edge $(\vartheta k,k)$; hence $\varsigma_{kk}=0$. Every cross edge joins some $j\in U^+$ to some $\vartheta k$, $k\in U^+$, in one orientation, which is the bijection. The degree of $k$ is $d^0_k$ plus the number of $k'$ with $\varsigma_{kk'}\ne0$, which is $r_k$ by antisymmetry; $\vartheta$ is an automorphism, so $\vartheta k$ has the same degree. The last claim is the automorphism property restricted to $U^+$. \end{proof} Fix a prime $p$. Put $\mathcal I^+=\operatorname{Inj}_p(G^+)$, $\mu=\mu_p=\lambda_p(G^+)$ (uniform on $\mathcal I^+$; the \emph{half law}) and $\lambda=\lambda_p(G)$ (throughout this section $\mu,\lambda$ are these local graph laws, not the reference and first-stage laws of Part~III). For $y\in\Fp^U$ write $x=y|_{U^+}$ ($x_k=y_k$) and $x'=(y\circ\vartheta)|_{U^+}$ ($x'_k=y_{\vartheta k}$). For $(j,k)\in E_\times$ the cross constraint of the edge between $j$ and $\vartheta k$ reads $\varsigma_{jk}(x'_k-x_j)\in\Qsq$. The identification of a labelling $y$ of the whole graph with the pair $(x,x')$ of labellings of $G^+$, and this form of the cross constraints, are what the whole spectral method rests on. \begin{lemma}[Cut kernel]\label{lem:spec:cutkernel} Let spectral data satisfy $e_\Delta(p,2n)<1$. \begin{enumerate}[label=\textup{(\alph*)}] \item $\operatorname{Inj}_p(G)$ and $\mathcal I^+$ are nonempty, and $y\mapsto(x,x')$ is a bijection of $\operatorname{Inj}_p(G)$ onto $\{(x,x')\in\mathcal I^+\times\mathcal I^+:K(x,x')=1\}$, where \begin{equation}\label{eq:spec:K} K(x,x')=\one\{x(U^+)\cap x'(U^+)=\emptyset\}\prod_{(j,k)\in E_\times} \Ap\big(\varsigma_{jk}(x'_k-x_j)\big). \end{equation} Moreover $K(x,x')=K(x',x)$. \item Under $\lambda$ the pair $(x,x')$ has law $\mu\otimes\mu\cdot K/Z$ with $Z=Z_p=\E_{\mu\otimes\mu}K>0$, and $x$, $x'$ have the same law $m_p$, the \emph{actual half marginal}. The \emph{normalized cut operator} $\Op$ (the operator $A_p$ of the roadmaps) on $L^2(\mu)$, $(\Op H)(x)=\E_{x'\sim\mu}[K(x,x')H(x')]/Z$, is self-adjoint, $\E_\lambda[F(x)H(x')]=\ip F{\Op H}_\mu$ for real $F,H$, and $\Op\one=\varrho:=dm_p/d\mu$. \item For $x\in\mathcal I^+$ let $N(x)=\#\{x'\in\mathcal I^+:K(x,x')=1\}$. Then $N_-\le N(x)\le N_+$ for every $x$, with $N_\pm=\prod_{i=1}^np2^{-t_i}\big(1\pm e_{t_i}(p,2n)\big)$ and $N_+/N_-=\Rcut(p)$. Hence $\Rcut(p)^{-1}\le\varrho\le\Rcut(p)$ on $\mathcal I^+$, and $2^{-m_\times}\Rcut(p)^{-1}\le Z\le2^{-m_\times}\Rcut(p)$. \item $\lambda$, $\mu$ and $m_p$ are invariant under the diagonal maps $z\mapsto(az_u+c)_u$ ($a\in\Qsq$, $c\in\Fp$), every one-vertex marginal of $\lambda$, $\mu$ and $m_p$ is uniform on $\Fp$, and $\lambda$ is invariant under $(x,x')\mapsto(x',x)$. \item Let $B$ be a finite set of odd primes with $e_\Delta(p,2n)<1$ for $p\in B$, $X=\prod_{p\in B}\Fp$, $\lambda_B(G)=\bigotimes_p\lambda_p(G)$, $\mu_B=\bigotimes_p\mu_p$ and $\mathsf A_B=\bigotimes_{p\in B}\Op$ on $L^2(\mu_B)=\bigotimes_pL^2(\mu_p)$. Then for all real $F,H:X^{U^+}\to\R$, $\E_{y\sim\lambda_B(G)}[F(x)H(x')]=\ip F{\mathsf A_BH}_{\mu_B}$. \item \emph{(Positive reweightings.)} Let $w\ge0$ be a function on $\operatorname{Inj}_p(G)$ with $\E_\lambda w>0$, write $w(x,x')$ for its value at the labelling with halves $(x,x')$ (and put $w(x,x')K(x,x')=0$ where $K(x,x')=0$), and let $\lambda^w=w\lambda/\E_\lambda w$. Under $\lambda^w$ the pair $(x,x')$ has law $\mu\otimes\mu\cdot wK/(Z\E_\lambda w)$. The operator $\Op^w$ on $L^2(\mu)$ with kernel $wK/(Z\E_\lambda w)$ relative to $\mu\otimes\mu$ satisfies $\E_{\lambda^w}[F(x)H(x')]=\ip F{\Op^wH}_\mu$ for real $F,H$, and $\Op^w\one=dm^w_p/d\mu$, where $m^w_p$ is the law of $x$ under $\lambda^w$; $\Op^w$ is self-adjoint if $w(x,x')=w(x',x)$. For a block $B$ as in (e) and $w_B=\prod_{p\in B}w_p$, the identity of (e) holds for $\lambda_B(G)^{w_B}=\bigotimes_p\lambda_p(G)^{w_p}$ with $\bigotimes_p\Op^{w_p}$ in place of $\mathsf A_B$. \end{enumerate} \end{lemma} \begin{proof} (a) $G$ has $2n$ vertices and maximum degree $\Delta$ (\cref{lem:spec:elementary}), so $\operatorname{Inj}_p(G)\ne\emptyset$ by \cref{lem:graphs:sequential}, and restriction gives $\mathcal I^+\ne\emptyset$. Since $\vartheta$ is a bijection, $y$ is determined by $(x,x')$. The constraints defining $\operatorname{Inj}_p(G)$ are: the edges inside $U^+$ and injectivity on $U^+$, which say $x\in\mathcal I^+$; the edges inside $U^-$ and injectivity on $U^-$, which say $x'\in\mathcal I^+$, because $\vartheta$ maps $G^+$ onto $G[U^-]$ with orientations; the cross edges, which are the factors of \eqref{eq:spec:K} by \cref{lem:spec:elementary}; and injectivity across the cut, the first factor. The map $y\mapsto y\circ\vartheta$ is a bijection of $\operatorname{Inj}_p(G)$ (an automorphism preserves injectivity and the constraints), and it maps $(x,x')$ to $(x',x)$; hence the image set is symmetric, and $K$, its indicator, is symmetric. (b) $\lambda$ is uniform, so the law of $(x,x')$ is the uniform law on $\{K=1\}$, which is $\mu\otimes\mu\cdot K/Z$ with $Z=|\operatorname{Inj}_p(G)|/|\mathcal I^+|^2>0$. The swap symmetry of (a) shows that $x$ and $x'$ have the same law. $\Op$ has a real symmetric kernel, so it is self-adjoint, and $\ip F{\Op H}_\mu$ equals $\E_{\mu\otimes\mu}[F(x)K(x,x')H(x')]/Z=\E_\lambda[F(x)H(x')]$. Finally $m_p(x)=N(x)/|\operatorname{Inj}_p(G)|$ and $\mu(x)=1/|\mathcal I^+|$, so $(\Op\one)(x)=N(x)/(Z|\mathcal I^+|)=m_p(x)/\mu(x)$. (c) By the automorphism $\vartheta$, $N(x)$ is the number of labellings of $U^+$ that extend the labelling $x\circ\vartheta$ of $U^-$ to an element of $\operatorname{Inj}_p(G)$. Label $U^+$ in the order $v_n,v_{n-1},\dots,v_1$. When $v_i$ is labelled, its labelled neighbours are its $t_i$ neighbours in $U\setminus\{v_1,\dots,v_i\}$, their labels are distinct, and fewer than $2n$ labels are in use. By \cref{lem:extension} (with the used labels as excluded set) the number of choices lies in $p2^{-t_i}[1-e_{t_i}(p,2n),1+e_{t_i}(p,2n)]$, whatever the earlier choices; here $e_{t_i}(p,2n)\le e_\Delta(p,2n)<1$. Multiplying gives $N_-\le N(x)\le N_+$, and $N_+/N_-=\Rcut(p)$ by \eqref{eq:spec:Rcut}. By (b), $\varrho=N|\mathcal I^+|/|\operatorname{Inj}_p(G)|=N/\E_\mu N$, so it lies in $[N_-/N_+,N_+/N_-]$. For $Z$, label $U^+$ alone in the same order: $v_i$ then has $t^0_i\le t_i$ labelled neighbours (those in $G^+$) and fewer than $n$ labels are in use, so $|\mathcal I^+|\in\prod_ip2^{-t^0_i}[1-e_{t^0_i}(p,n),1+e_{t^0_i}(p,n)]$ with $e_{t^0_i}(p,n)\le e_{t_i}(p,2n)$. Since $\sum_it_i=e(U^+)+m_\times$ (each edge inside $U^+$ is counted at its earlier-deleted endpoint, each cross edge at its end in $U^+$, and there are $m_\times$ cross edges by \cref{lem:spec:elementary}) and $\sum_it^0_i=e(U^+)$, comparing the two products factor by factor shows that the quotient $Z=|\operatorname{Inj}_p(G)|/|\mathcal I^+|^2=\E_\mu N/|\mathcal I^+|$ lies in $2^{-m_\times}[\Rcut^{-1},\Rcut]$. (d) $\lambda$ and $\mu$ are uniform laws on injective strict-square labellings, hence square-affine invariant, and $m_p$ is the image of $\lambda$ under the coordinate map $y\mapsto x$; so all three are invariant and have uniform one-vertex marginals by \cref{lem:marginals}(1),(2). The swap invariance is (a). (e) All laws and kernels are products over $p\in B$, and the identity follows from (b) for product functions and then for all $F,H$ by bilinearity, since product functions span $\bigotimes_pL^2(\mu_p)$. (f) Through the bijection of (a), $\lambda^w$ has the density $w/\E_\lambda w$ relative to $\lambda$, so by (b) the pair $(x,x')$ has the law $\mu\otimes\mu\cdot wK/(Z\E_\lambda w)$ under $\lambda^w$. Hence \[ \ip F{\Op^wH}_\mu=\frac{\E_{\mu\otimes\mu}[F(x)\,(wK)(x,x')\,H(x')]}{Z\E_\lambda w} =\E_{\lambda^w}[F(x)H(x')], \] and $(\Op^w\one)(x)$ is the density of the law of $x$ under $\lambda^w$ relative to $\mu$. The kernel is real, and it is symmetric when $w$ is, because $K$ is symmetric. For a block, $\E_{\lambda_B(G)}w_B=\prod_p\E_{\lambda_p(G)}w_p$, so $\lambda_B(G)^{w_B}$ is the product of the laws $\lambda_p(G)^{w_p}$, and the identity follows from the prime identity for product functions and bilinearity, as in (e). \end{proof} Thus the full labelling law is the product of two copies of the half law reweighted by the cross kernel; every cut-operator estimate starts from this identity, and parts (a)--(c) use the reflection only to identify the two halves. Part (f) is the form in which the positive roots of the late middle pieces are measured (\cref{sec:positive-roots}): the reference stays the half law $\mu$, and the reweighting enters only the kernel and the constant image $\Op^w\one$. The factor $2^{-m_\times}$ in (c) is the expected mass of the cross constraints; normalizing by the exact mass $Z$ instead is what makes the later estimates relative. The norm matters too: $\Op$ acts on $L^2$ of the half law $\mu$, not of the actual half marginal $m_p$, and by (c) the two norms differ by a factor in $[\Rcut^{-1/2},\Rcut^{1/2}]$. The comparison records of Part~V are measured in the actual marginals (\cref{subsec:cuts:actual,subsec:cuts:recentering}). We write $Q(F)=\ip F{\Op F}_\mu=\E_\lambda[F(x)F(x')]$ for real $F$, and $\mathcal B(F,H)=\E_\lambda[F(x)H(x')]$ for the symmetric bilinear form (symmetric by the swap invariance). For a set $S\subseteq U^+$ and a value $s$ with $\mu(x_S=s)>0$ (a \emph{feasible pinning}) the conditional law is $\mu(\cdot\mid x_S=s)$. \begin{lemma}[Transport along isomorphisms]\label{lem:cut-transport} Let $(G,\vartheta,U^+)$ and $(G',\vartheta',U'^+)$ satisfy \textup{(S0)}, and let $\phi\colon U\to U'$ be an isomorphism of oriented graphs with $\phi(U^+)=U'^+$ and $\phi\circ\vartheta=\vartheta'\circ\phi$. Then $y\mapsto y\circ\phi^{-1}$ is a bijection $\operatorname{Inj}_p(G)\to\operatorname{Inj}_p(G')$ which maps the halves $(x,x')$ of $y$ to the halves $(x\circ\phi^{-1},x'\circ\phi^{-1})$ of $y\circ\phi^{-1}$. Consequently $\Phi F(\xi)=F(\xi\circ\phi)$ defines a unitary operator $L^2(\mu_p)\to L^2(\mu'_p)$ with $\Phi\Op\Phi^*=\Op'$ and $\Phi\varrho=\varrho'$; $\Phi$ maps the functions of the labels of $A\subseteq U^+$ onto the functions of the labels of $\phi(A)$, so the compressions of $\Op$ and $\Op'$ to corresponding subspaces are unitarily equivalent; the same holds over a block of primes with $\bigotimes_p\Phi$; and if $\phi$ maps $\mathfrak o$ to a deletion order $\mathfrak o'$, the row ratios agree. In particular, if $\phi$ is an automorphism of $G$, the cut operators of $\lambda_p(G)$ at the cuts $(U^+,\vartheta)$ and $(\phi(U^+),\phi\vartheta\phi^{-1})$ are unitarily equivalent. \end{lemma} \begin{proof} $\phi$ maps edges to edges with orientations, and $(y\circ\phi^{-1})(\phi w)-(y\circ\phi^{-1})(\phi u)=y(w)-y(u)$, so $y\circ\phi^{-1}\in\operatorname{Inj}_p(G')$ iff $y\in\operatorname{Inj}_p(G)$. The new halves are $(y\circ\phi^{-1})|_{U'^+}=x\circ\phi^{-1}$ and $(y\circ\phi^{-1}\circ\vartheta')|_{U'^+}=(y\circ\vartheta\circ\phi^{-1})|_{U'^+} =x'\circ\phi^{-1}$, using $\phi^{-1}\circ\vartheta'=\vartheta\circ\phi^{-1}$. Since $\phi$ maps $G^+$ onto $G'^+$, the half law $\mu'_p$ is the image of $\mu_p$ under $x\mapsto x\circ\phi^{-1}$, so $\Phi$ is unitary, and \[ \ip{\Phi F}{\Op'\Phi H}_{\mu'_p}=\E_{\lambda_p(G')}\big[(\Phi F)(x\circ\phi^{-1}) (\Phi H)(x'\circ\phi^{-1})\big]=\E_{\lambda_p(G)}[F(x)H(x')]=\ip F{\Op H}_{\mu_p} \] by \cref{lem:spec:cutkernel}(b). The actual half marginals correspond in the same way, which gives $\Phi\varrho=\varrho'$. The statements on functions of a vertex set and on blocks are immediate, and the deletion degrees are preserved because $\phi$ preserves adjacency. \end{proof} \subsection{From mean-zero bounds to operator bounds}\label{subsec:cuts:blocks} Several facts turn a spectral bound for one normalized operator at one prime into the bounds the construction uses. An upper bound on the mean-zero compression, together with a small constant image, gives a positive envelope $1+O(1/p)$ (\cref{prop:matching:positive}); a lower bound on the compression gives the matching lower envelope; and for an operator commuting with translations the centred bound may be split between the translation-invariant functions and their complement. The envelopes at the primes of a block tensorize, the upper envelopes contributing the factor $\prod_p(1+c^+/p)\le\exp(c^+\sum_p1/p)$ (\cref{lem:spec:tensorcomp}). The operators $\Op$ act on the reference half law and are not Markov: their upper spectrum exceeds $1$ by about $c^+/p$, and that excess is the source of the inflation factor. Markov operators of couplings, taken in their actual marginals, pay only the maximum of their factors under tensor products (\cref{lem:sector}(c)); this is one reason why the comparison records of Part~V keep their actual marginals. Two more tools bound syntheses of many feature maps: weighted frames (finite families of feature maps with a positive weight vector, bounded through the largest eigenvalue of a symmetric majorant matrix; \cref{lem:weighted-frame}), and swapped rectangular kernels, whose nonzero eigenvalues are, up to sign, products of two singular values of the rectangle (\cref{lem:swapped-rectangle}). The projections $\Jproj$ and $P_0=I-\Jproj$ are those of \cref{subsec:notation:conventions}. The following identity is the common reason that eliminating one diagonal block loses at most the square of the coupling norm divided by the lower bound of that block. It will be used both for the constant direction of a normalized kernel and for smaller compressions in Part~V. \begin{lemma}[Block completion]\label{lem:block-completion} Let $T=\begin{psmallmatrix}A&B^*\\B&D\end{psmallmatrix}$ be self-adjoint on a finite-dimensional orthogonal sum $\mathcal H_1\oplus\mathcal H_2$, and put $b=\norm B$. \begin{enumerate}[label=\textup{(\alph*)}] \item If $A\succeq sI$ with $s>0$, then \[ \ip{(x,y)}{T(x,y)} =\norm{A^{1/2}x+A^{-1/2}B^*y}^2 +\ip y{(D-BA^{-1}B^*)y}. \] Consequently $T\succeq0$ if and only if $D-BA^{-1}B^*\succeq0$, and $D-BA^{-1}B^*\succeq D-(b^2/s)I$. \item If $A\succeq aI$, $D\succeq dI$ and $a>d$, then \[ T\succeq\left(d-\frac{b^2}{a-d}\right)I. \] Dually, if $A\preceq aI$, $D\preceq dI$ and $a>d$, then $T\preceq\left(a+\frac{b^2}{a-d}\right)I$. \end{enumerate} \end{lemma} \begin{proof} Expanding the square gives (a); choosing $x=-A^{-1}B^*y$ proves the necessity of its positivity criterion, and $A^{-1}\preceq s^{-1}I$ gives the residual bound. For (b), put $\lambda=d-b^2/(a-d)$. The first diagonal block of $T-\lambda I$ is at least $(a-d)I$, and the second is at least $b^2/(a-d)I$, so (a) gives $T-\lambda I\succeq0$. Apply this lower bound to $-T$ with the two summands interchanged to obtain the upper bound. \end{proof} \begin{proposition}[Positive envelope from the mean-zero compression]\label{prop:matching:positive} Let $(\Omega,\nu)$ be a finite probability space with full support and $A$ a self-adjoint operator on $L^2(\nu)$ with $\ip\one{A\one}=1$. \begin{enumerate}[label=\textup{(\alph*)}] \item If $\norm{P_0A\one}\le e$ and $P_0AP_0\preceq\beta P_0$ with $\beta<1$, then $A\preceq\big(1+\frac{e^2}{1-\beta}\big)I$. \item[\textup{(a$'$)}] \emph{(Lower envelope.)} If $\norm{P_0A\one}\le e$ and $P_0AP_0\succeq-gP_0$ with $g\ge0$, then $A\succeq-\big(g+\frac{e^2}{1+g}\big)I$. \item[\textup{(a$''$)}] \emph{(Translation sectors.)} Let a finite group act on $\Omega$ preserving $\nu$, let $A$ commute with the induced unitary operators $f\mapsto f\circ\gamma^{-1}$, and let $\mathcal I\ni\one$ be the space of invariant functions. Then $A$ preserves $\mathcal I$ and $\mathcal I^\perp$, and $u=P_0A\one\in\mathcal I$. If $\norm{A|_{\mathcal I^\perp}}\le C$, $\norm{P_0AP_0|_{\mathcal I}}\le H<1$ and $\norm u^2\le\vartheta_u$, then \[ -\max(C,H+\vartheta_u)\,I\preceq A\preceq\max\Big(C,\,1+\frac{\vartheta_u}{1-H}\Big)I . \] \item[\textup{(b)}] \emph{(Normalized kernels.)} Let $K\ge0$ be a symmetric kernel on $\Omega\times\Omega$ with operator $T_Kf(x)=\E_{y\sim\nu}K(x,y)f(y)$, and suppose that $\norm{T_K-k\Jproj}\le k\eps$ for some $k>0$ and $0\le\eps<1$. Put $z=\ip\one{T_K\one}/k$, $A=T_K/(kz)$ and $\hat\eps=\eps/(1-\eps)$. Then $|z-1|\le\eps$, $\ip\one{A\one}=1$, $\norm{P_0A\one}\le\hat\eps$, $\norm{P_0AP_0}\le\hat\eps$ and $A\succeq-\hat\eps I$; if $\hat\eps<1$, then $A\preceq(1+\hat\eps^2/(1-\hat\eps))I$. \item[\textup{(c)}] \emph{(All primes above a threshold.)} Suppose that for every prime $p\ge p_0$ an operator $A=A_p$ as above satisfies (a) with $e=e(r)$ and $\beta=gr$, where $e(r)/r$ is nondecreasing in $r=p^{-1/2}$ and $gr_0<1$, $r_0=p_0^{-1/2}$. Then $A_p\preceq(1+B^+/p)I$ for every prime $p\ge p_0$, with $B^+=p_0\,e(r_0)^2/(1-gr_0)$. \end{enumerate} \end{proposition} \begin{proof} (a), (a$'$) Relative to $\langle\one\rangle\oplus\one^\perp$, the operator has diagonal blocks $1$ and $P_0AP_0$, and coupling vector $P_0A\one$ of norm at most $e$. Apply the upper and lower bounds of \cref{lem:block-completion}(b), respectively, with diagonal bounds $(1,\beta)$ and $(1,-g)$. (a$''$) For a group element $\gamma$ the operator $U_\gamma f=f\circ\gamma^{-1}$ is unitary on $L^2(\nu)$ and fixes $\one$, so it commutes with $\Jproj$ and $P_0$. If $f\in\mathcal I$, then $U_\gamma Af=AU_\gamma f=Af$ for every $\gamma$; so $A$ preserves $\mathcal I$, and, being self-adjoint, also $\mathcal I^\perp$. Hence $A\one\in\mathcal I$, $u=P_0A\one$ lies in $\mathcal I_0=\mathcal I\cap\one^\perp$, and $D_{\mathcal I}=P_0AP_0|_{\mathcal I_0}$ is a self-adjoint operator on $\mathcal I_0$ with $\norm{D_{\mathcal I}}\le H$. As $L^2(\nu)=\mathcal I\oplus\mathcal I^\perp$ and $A$ preserves both summands, it suffices to bound $A$ on each; on $\mathcal I^\perp$, $-CI\preceq A\preceq CI$. On $\mathcal I$, parts (a) and (a$'$), with $e^2=\vartheta_u$ and $\beta=g=H$, give the upper bound $1+\vartheta_u/(1-H)$ and the lower bound $-H-\vartheta_u/(1+H)\ge-H-\vartheta_u$. Combining these with the bounds on $\mathcal I^\perp$ proves the claim. (b) Write $T_K=k\Jproj+D$ with $\norm D\le k\eps$. Then $kz=\ip\one{T_K\one}=k+\ip\one{D\one}$, so $|z-1|\le\eps$, and clearly $\ip\one{A\one}=1$. Since $P_0\Jproj=\Jproj P_0=0$, $P_0A\one=P_0D\one/(kz)$ and $P_0AP_0=P_0DP_0/(kz)$ have norms at most $\eps/z\le\hat\eps$. Next $A=\Jproj/z+D/(kz)\succeq D/(kz)\succeq-(\eps/z)I\succeq-\hat\eps I$. Finally $P_0AP_0\preceq\hat\eps P_0$, and (a) with $e=\beta=\hat\eps$ gives the upper bound. (c) For $p\ge p_0$, $r\le r_0$, and $e(r)^2/(1-gr)=r^2(e(r)/r)^2/(1-gr)\le r^2(e(r_0)/r_0)^2/(1-gr_0)=B^+/p$. Insert this in (a). \end{proof} Part (a) is the positive envelope of both spectral criteria: with $e=\eps_\varrho$ (the bound on $\norm{P_0\Op\one}$ of \ref{it:centre:inputs}) and $\beta=gr$ it gives $A\preceq(1+\eps_\varrho^2/(1-gr))I$ at one prime, which (c) turns into the threshold bound $1+B^+/p$ of \cref{thm:spectral-criterion}, and with $\beta=g_{\rm root}r$ it gives that of \cref{thm:record:direct-star}. It also covers an operator written as $A=\ip{w}{\cdot}\,w+R$ with $w$ real, $\ip\one w=1$, $\norm{w-\one}\le v$, and $R=P_0RP_0$ self-adjoint with $\norm R\le d$: then $\ip\one{A\one}=1$, $P_0A\one=w-\one$ and $P_0AP_0\preceq(d+v^2)P_0$, so $A\preceq\big(1+v^2/(1-d-v^2)\big)I$ when $d+v^2<1$. With (a), parts (a$'$) and (a$''$) give the two-sided caps $-gp^{-1/2}I\preceq T_p\preceq(1+c^+/p)I$ of the cuts whose centred blocks are bounded directly: (a$''$) gives the upper cap of the cut L20 of the uniform root (\cref{subsec:middle-l20}); (a) and (a$'$) give both caps of the chamber cut of a positive root on one of the seven middle intervals with least prime at least $2^{30}$ (\cref{prop:root-chamber}), and (a) the upper cap of its layer cut (\cref{prop:root-layer}); and (a$'$) gives the lower caps of the merge and constant compressions of the upper range (\cref{prop:observed-caps}). At the cut L20 the group of (a$''$) is the group of simultaneous translations of all labels: it preserves the half law (\cref{lem:spec:cutkernel}(d)) and commutes with the cut operator, because the kernel \eqref{eq:spec:K} depends only on differences of labels. \begin{lemma}[Tensor products of compressions]\label{lem:spec:tensorcomp} \leavevmode \begin{enumerate}[label=\textup{(\alph*)}] \item \emph{(Tensor spectrum, \cref{lem:sector}(g).)} If $C_1,\dots,C_k$ are self-adjoint operators on finite-dimensional Hilbert spaces with spectra in $[-g_i,1+b_i]$, where $b_i\ge0$ and $0\le g_i\le1+b_i$, then $\bigotimes_iC_i\succeq-\max_i\big(g_i\prod_{j\ne i}(1+b_j)\big)I \succeq-(\max_ig_i)\exp(\sum_ib_i)I$. \item Let $B$ be a finite set of odd primes, $b=\min B$, and for $p\in B$ let $T_p$ be a self-adjoint operator on a finite-dimensional Hilbert space with \[ -gp^{-1/2}I\preceq T_p\preceq(1+c^+/p)I,\qquad gp^{-1/2}<1, \] where $g,c^+\ge0$. Then \[ \bigotimes_{p\in B}T_p\succeq-\frac g{\sqrt b}\prod_{p\in B}\Big(1+\frac{c^+}p\Big)I \succeq-\frac g{\sqrt b}\exp\Big(c^+\sum_{p\in B}\frac1p\Big)I, \] and if $B=\{p\}$ the bound is $-gp^{-1/2}I$. In particular, let spectral data be given with $e_\Delta(p,2n)<1$ for $p\in B$, and for $p\in B$ let $\mathcal V_p\subseteq L^2(\mu_p)$ be a subspace with \[ -gp^{-1/2}\norm F^2\le\ip F{\Op F}_{\mu_p}\le(1+c^+/p)\norm F^2\qquad (F\in\mathcal V_p), \] with $g,c^+\ge0$ and $gp^{-1/2}<1$ as above. Then for every $F\in\bigotimes_{p\in B}\mathcal V_p$ \[ \ip F{\mathsf A_BF}_{\mu_B}\ge-\frac g{\sqrt b}\prod_{p\in B}\Big(1+\frac{c^+}p\Big) \norm F^2_{\mu_B}\ge-\frac g{\sqrt b}\exp\Big(c^+\sum_{p\in B}\frac1p\Big) \norm F^2_{\mu_B}, \] and if $B=\{p\}$ the bound is $-gp^{-1/2}\norm F^2$. For $A\subseteq U^+$ the functions of $x_A$ in $L^2(\mu_B)$ form the subspace $\bigotimes_p\mathcal V_{A,p}$, where $\mathcal V_{A,p}$ is the space of functions of $x_{A,p}$ in $L^2(\mu_p)$; so (b) applies to the compression to the functions of the labels of a vertex set. \item If $\log\prod_{p\in B}p\le L$, then $|B|\le L/\log b$ and $\sum_{p\in B}1/p\le L/(b\log b)$. \end{enumerate} The lower and the upper bound in (b) may come from different arguments. The upper bound for $\mathcal V_p=L^2(\mu_p)$, which bounds every compression, is supplied by \cref{prop:matching:positive}(c), with $c^+=B^+$. \end{lemma} \begin{proof} (a) is \cref{lem:sector}(g) with $c_i=g_i$. (b) Apply (a) to the operators $T_p$, with $g_p=gp^{-1/2}\le gb^{-1/2}$ and $b_p=c^+/p$; the condition $g_p\le1+b_p$ holds since $gp^{-1/2}<1$, and $g_p\prod_{p'\ne p}(1+b_{p'})\le gb^{-1/2}\prod_{p'\in B}(1+b_{p'})$. For a single prime the product over $p'\ne p$ is empty. For spectral data let $P_p$ be the orthogonal projection of $L^2(\mu_p)$ onto $\mathcal V_p$ and $C_p=P_p\Op P_p|_{\mathcal V_p}$, a self-adjoint operator on $\mathcal V_p$ whose spectrum lies in its numerical range, hence in $[-gp^{-1/2},1+c^+/p]$. On $\bigotimes_p\mathcal V_p\subseteq L^2(\mu_B)$, $(\bigotimes_pP_p)(\bigotimes_p\Op)(\bigotimes_pP_p)=\bigotimes_pC_p$, so $\ip F{\mathsf A_BF}=\ip F{(\bigotimes_pC_p)F}$ for $F\in\bigotimes_p\mathcal V_p$, and the first statement applies with $T_p=C_p$. The last statement holds because $\mu_B$ is a product and $x_A=(x_{A,p})_{p\in B}$, so the functions of $x_A$ are spanned by the products $\prod_pf_p(x_{A,p})$. (c) is \cref{lem:majorant}(c) with $X=b$, since $q_B=\prod_{p\in B}p\le e^L$. \end{proof} By (c), a block of logarithmic length at most $L$ whose least prime $b$ is at least $X$ has $\sum_{p\in B}1/p\le L/(b\log b)\le L/(X\log X)$. So if the caps of (b) hold with the same $g,c^+$ at every prime $p\ge X$, then \[ \bigotimes_{p\in B}T_p\succeq-g\exp\Big(\frac{c^+L}{X\log X}\Big)\,b^{-1/2}I : \] so the displayed lower bound, with the number $g\exp(c^+L/(X\log X))$ in place of $g$, holds for every such block. Part (b) uses only the two caps of each $T_p$, so it applies as well to the cut operators of positive reweightings (\cref{lem:spec:cutkernel}(f)) and to their compressions to subspaces. \paragraph{Weighted frames.} Many estimates of Part~V bound a sum of feature maps whose ranges are not orthogonal, through a matrix of bounds for their pairwise overlaps. The next lemma is the general form of that step; its part (c) reduces the largest eigenvalue of a symmetric majorant to a small matrix when the majorant has symmetries. \begin{lemma}[Weighted frames]\label{lem:weighted-frame} Let $V_i\colon\mathcal H_i\to\mathcal H$ ($i\in I$, $I$ finite) be operators between finite-dimensional Hilbert spaces, and let $G=(G_{ij})_{i,j\in I}$ be a symmetric matrix with nonnegative entries such that $\norm{V_i^*V_j}\le G_{ij}$ for all $i,j$ (for isometries one may take $G_{ii}=1$). \begin{enumerate}[label=\textup{(\alph*)}] \item For $d_i\ge0$ and $D=\operatorname{diag}(d_i)$, \[ \Big\|\sum_id_iV_iV_i^*\Big\|\le\lambda_{\max}(D^{1/2}GD^{1/2}) \le\max_i\sum_jG_{ij}d_j ; \] equivalently, the synthesis map $(z_i)_i\mapsto\sum_i\sqrt{d_i}V_iz_i$ from $\bigoplus_i\mathcal H_i$ to $\mathcal H$ has squared norm at most these numbers. In particular $\norm{\sum_iV_iV_i^*}\le\lambda_{\max}(G)$. \item For finitely many such families $(V^{(k)}_i)_{i\in I_k}$ with matrices $G^{(k)}$, the tensor products $\bigotimes_kV^{(k)}_{i_k}$, indexed by $\prod_kI_k$, satisfy the hypothesis with the Kronecker product $\bigotimes_kG^{(k)}$. \item \emph{(Perron gate.)} Let $G$ be any symmetric matrix with nonnegative entries indexed by $I$, preserved by a group of permutations of $I$ ($G_{\sigma i,\sigma j}=G_{ij}$) with orbits $O_1,\dots,O_m$, and put $\bar G_{ab}=(|O_a||O_b|)^{-1/2}\sum_{i\in O_a,\,j\in O_b}G_{ij}$. Then $\lambda_{\max}(G)=\lambda_{\max}(\bar G)$. Hence $\lambda_{\max}(G)\le\lambda$ as soon as $\lambda I-\bar G\succeq0$, which may be verified by eliminating positive diagonal entries (Schur complements). \end{enumerate} In applications of (a), any smaller bound for $\lambda_{\max}(G)$ may replace the row-sum bound. \end{lemma} \begin{proof} (a) The synthesis map $S(z_i)_i=\sum_i\sqrt{d_i}V_iz_i$ has the adjoint $S^*h=(\sqrt{d_i}V_i^*h)_i$, so $SS^*=\sum_id_iV_iV_i^*$ and $\norm{\sum_id_iV_iV_i^*}=\norm{S^*S}$. For $z=(z_i)_i$ put $w_i=\norm{z_i}$; then \[ \ip z{S^*Sz}=\sum_{i,j}\sqrt{d_id_j}\ip{z_i}{V_i^*V_jz_j} \le\sum_{i,j}\sqrt{d_id_j}\,G_{ij}w_iw_j=\ip w{D^{1/2}GD^{1/2}w}, \] which is at most $\lambda_{\max}(D^{1/2}GD^{1/2})\norm z^2$, since $\norm w=\norm z$, and $S^*S\succeq0$ has norm equal to the supremum of this form over unit vectors. Deleting the indices with $d_i=0$ removes a zero block of $D^{1/2}GD^{1/2}$ and does not increase the row sums; for $d_i>0$ the matrix $D^{1/2}GD^{1/2}=D^{1/2}(GD)D^{-1/2}$ is similar to $GD$, whose eigenvalues are at most its largest row sum $\max_i\sum_jG_{ij}d_j$ in modulus, because its entries are nonnegative. (b) For multi-indices $(i_k)$, $(j_k)$, $(\bigotimes_kV^{(k)}_{i_k})^*(\bigotimes_kV^{(k)}_{j_k})=\bigotimes_kV^{(k)*}_{i_k}V^{(k)}_{j_k}$, whose norm is the product of the norms of the factors, at most $\prod_kG^{(k)}_{i_kj_k}$, the entry of the Kronecker product; this matrix is symmetric with nonnegative entries. (c) Let $v$ be a real unit eigenvector of $G$ for $\lambda_1=\lambda_{\max}(G)$, and let $|v|$ be its entrywise modulus. Since the entries of $G$ are nonnegative, $\ip{|v|}{G|v|}\ge\ip v{Gv}=\lambda_1$, so $|v|$ maximizes the Rayleigh quotient and is an eigenvector for $\lambda_1$. The permutation matrices of the group commute with $G$, so the average $\bar v$ of the images of $|v|$ under the group is again an eigenvector for $\lambda_1$; it is nonzero, since it is nonnegative with the same positive entry sum as $|v|$, and it is invariant. The invariant vectors are those constant on every orbit, with the orthonormal basis $e_a=\one_{O_a}/|O_a|^{1/2}$; $G$ maps them to invariant vectors, and $\ip{e_a}{Ge_b}=\bar G_{ab}$. So $\bar G$ is the matrix of the restriction of $G$ to the invariant vectors, a compression of $G$, which gives $\lambda_{\max}(\bar G)\le\lambda_1$; and $\bar v$ is an eigenvector of that restriction for $\lambda_1$, which gives the reverse inequality. \end{proof} When $G$ has unit diagonal, $\lambda_{\max}(G)=1+\lambda_{\max}(G-I)$, and (c) may be applied to the off-diagonal part $G-I$. For example, for arbitrary nonnegative numbers $\varrho_{01},\varrho_{02}, \varrho_{03},\varrho_{34}$, five features with the off-diagonal bounds $G_{01}=G_{12}=\varrho_{01}$, $G_{02}=\varrho_{02}$, $G_{03}=G_{24}=\varrho_{03}$, $G_{34}=\varrho_{34}$ (and zero elsewhere), as the fold features of \cref{lem:oct24:feature-block}, admit the symmetry that exchanges $0\leftrightarrow2$ and $3\leftrightarrow4$; its orbits are $\{0,2\}$, $\{3,4\}$ and $\{1\}$, and the Perron block of the off-diagonal part is \[ \begin{pmatrix}\varrho_{02}&\varrho_{03}&\sqrt2\,\varrho_{01}\\ \varrho_{03}&\varrho_{34}&0\\ \sqrt2\,\varrho_{01}&0&0\end{pmatrix}. \] Eliminating its last two diagonal entries shows that the synthesis map of the five features has squared norm at most $1+\lambda$ for every $\lambda$ with \[ \lambda>\varrho_{34},\qquad \lambda-\varrho_{02}-\frac{\varrho_{03}^2}{\lambda-\varrho_{34}} -\frac{2\varrho_{01}^2}\lambda\ge0 . \] The lemma also gives the diagonal caps of the positive envelopes (\cref{thm:envelopes}) and the frames of the complete actual stars (\cref{subsec:spec:actual-stars}). \paragraph{Swapped rectangular kernels.} At a root cut whose half factors into two independent parts, the soft kernel is a product of one rectangular kernel with its own transpose, the second coordinates of the two halves being exchanged. Its spectrum is then read off from the singular values of the rectangle, and products with kernel factors depending on a common auxiliary label factor through the same exchange. \begin{lemma}[Swapped rectangular kernels]\label{lem:swapped-rectangle} Let $(X,\alpha)$ and $(Y,\beta)$ be finite probability spaces with full support, let $A\colon L^2(\beta)\to L^2(\alpha)$ have the real kernel $A(x;y)$, $(Ah)(x)=\E_{y\sim\beta}A(x;y)h(y)$, and let $T[A,A]$ be the operator on $L^2(\alpha\otimes\beta)$ whose kernel relative to $\alpha\otimes\beta$ is $A(x;y')A(x';y)$ at $((x,y),(x',y'))$. \begin{enumerate}[label=\textup{(\alph*)}] \item $T[A,A](f\otimes g)=Ag\otimes A^*f$, that is, $T[A,A]=(A\otimes A^*)\operatorname{Swap}$ with $\operatorname{Swap}(f\otimes g)=g\otimes f$. Let $(u_i)$ and $(v_j)$ be orthonormal bases of $L^2(\alpha)$ and $L^2(\beta)$, and $\sigma_i\ge0$, with $Av_i=\sigma_iu_i$ and $A^*u_i=\sigma_iv_i$ for $i\le k=\min(|X|,|Y|)$, and $Av_j=0$, $A^*u_i=0$ for $j>k$, $i>k$ (a singular value decomposition). Then $T[A,A](u_i\otimes v_j)=\sigma_i\sigma_j\,u_j\otimes v_i$ for $i,j\le k$, and $T[A,A](u_i\otimes v_j)=0$ otherwise. So $T[A,A]$ is self-adjoint, its eigenvalues are the $\sigma_i^2$, the numbers $\pm\sigma_i\sigma_j$ ($i0$; then $\mu_{S,s}=\mu(\cdot\mid y_S=s)$ is uniform on the set $\Omega_{S,s}$ of completions, $F=U\setminus S$ is the set of \emph{free} vertices, and $\Delta_F=\max_{i\in F}d_i$. A pinning $(S',s')$ \emph{extends} $(S,s)$ if $S'\supseteq S$ and $s'|_S=s$. \begin{enumerate}[label=\textup{(\roman*)}] \item \emph{Count errors.} Numbers $w,w^{\rm conn}\in[0,1)$ are \emph{count errors for $(G,F)$ at $p$} if for all distinct $a_1,\dots,a_t\in\Fp$, all signs $\epsilon_1,\dots,\epsilon_t$ and every $E'\supseteq\{a_1,\dots,a_t\}$, the number $N=\#\{x\in\Fp\setminus E':\epsilon_i(x-a_i)\in\Qsq\ (1\le i\le t)\}$ satisfies \begin{equation}\label{eq:mid:standing} \frac{2^tN}p\ge1-w\quad\text{if }t\le\Delta_F,\ |E'|\le n,\qquad \frac{2^tN}p\ge1-w^{\rm conn}\quad\text{if }t\le\Delta_F+1,\ |E'|\le2n . \end{equation} By \cref{lem:extension}(d) and \ref{it:et:compare}, the coarse errors $w=w_{\Delta_F}(p,n)$ and $w^{\rm conn}=w_{\Delta_F+1}(p,2n)$ of \eqref{eq:graphs:et} are count errors whenever they are below one; by \cref{lem:extension}(c) and \ref{it:et:poly}, so are the graded errors $w=e^-_{\Delta_F}(n)$ and $w^{\rm conn}=e^-_{\Delta_F+1}(2n)$ of \eqref{eq:graphs:graded}. The two numbers are separate choices: one may be coarse and the other graded. \item \emph{Influence entries.} With $H_w=(1+w)/(1-w)^2$, for distinct $i,j\in F$ \begin{equation}\label{eq:mid:epsij} \eps_{ij}=\begin{cases}H_w\,2^{(d_i+d_j-2)/2}(r+r^2),&ij\text{ an edge (either orientation)},\\ H_w\,2^{(d_i+d_j)/2}r^2,&\text{otherwise},\end{cases} \end{equation} and $\eps_{ii}=0$. The \emph{influence matrix} is $\mathcal E=(\eps_{ij})_{i,j\in F}$. \end{enumerate} \end{definition} Only the free vertices are indexed, but their degrees $d_i$ include the edges to pinned vertices; the degrees of pinned vertices do not enter. The matrix $\mathcal E$ is symmetric with nonnegative entries, so $\norm{\mathcal E}$ is at most its maximal row sum. For either choice of count errors in (i), the numbers $w$, $w^{\rm conn}$, $H_w$ and $\eps_{ij}/r$ are admissible functions of $r$ in the sense of \cref{lem:majorant} (polynomials with nonnegative coefficients, and $x\mapsto1/(1-x)$ of them). The proof below gives \eqref{eq:mid:epsij} with $1/(1-w)$ in place of $H_w$ (\cref{lem:mid:pinpair}); we state \eqref{eq:mid:epsij} with $H_w$, the constant the certificates evaluate (\cref{tab:cert:finite}). \begin{definition}[Influence conditions] An oriented graph with $n$ vertices and maximum degree $\Delta$ satisfies the \emph{influence conditions at $p_0$} if \begin{equation}\label{eq:spec:S2} w_\Delta(p_0,n)<\frac12,\qquad w_{\Delta+1}(p_0,2n)<1,\qquad e<\frac14, \end{equation} with $w_\Delta$ as in \eqref{eq:graphs:et}, where $e$ is the maximal row sum, at $r=p_0^{-1/2}$, of the influence matrix of the empty pinning ($F=U$) with $w=w_\Delta(p_0,n)$. \end{definition} The three quantities are admissible functions of $r$, so the conditions at $p_0$ hold at every prime $p\ge p_0$, and there they give the hypotheses of \cref{prop:middle-negative} for the empty pinning ($\operatorname{Inj}_p(G)\ne \emptyset$ by \cref{lem:graphs:sequential}, since $e_\Delta(p,n)\le w_\Delta(p,n)<1$). For spectral data, the certificates assert \eqref{eq:spec:S2} for the half graph $G^+$ at every threshold at which \cref{thm:spectral-criterion} is applied (\cref{tab:cert:finite}); no theorem of this paper assumes \eqref{eq:spec:S2}. \begin{lemma}[Fully pinned pairs]\label{lem:mid:pinpair} In the setting of \cref{def:mid:influence}, let $w$ satisfy the first inequality of \eqref{eq:mid:standing}. Let $i,j\in F$ be distinct and let $z$ be a feasible value of $y_{U\setminus\{i,j\}}$ that extends $s$. Then $\rho(y_i;y_j\mid y_{U\setminus\{i,j\}}=z)\le\eps_{ij}$. \end{lemma} \begin{proof} Let $S_i$ be the set of $x\in\Fp\setminus z(U\setminus\{i,j\})$ satisfying the constraints between $i$ and the pinned vertices, and similarly $S_j$. Let $t_i$ be the number of pinned neighbours of $i$: $t_i=d_i-1$ if $ij$ is an edge and $t_i=d_i$ otherwise; similarly $t_j$. Given the pinning, $(y_i,y_j)$ is uniform on $\{(x,x')\in S_i\times S_j:K(x,x')=1\}$, where $K(x,x')=\Ap(\pm(x'-x))$ (sign by the orientation) if $ij$ is an edge, and $K(x,x')=\one\{x\ne x'\}$ otherwise. Let $a(x)=\sum_{x'\in S_j}K(x,x')$ and $b(x')=\sum_{x\in S_i}K(x,x')$. If $ij$ is an edge, $a(x)$ counts the labels of $j$ outside the $n-1$ values $z(U\setminus\{i,j\})\cup\{x\}$ that satisfy $t_j+1=d_j\le\Delta_F$ constraints with distinct roots (the pinned neighbours of $j$ and $x\notin z(U\setminus\{i,j\})$), so $a(x)\ge p2^{-d_j}(1-w)=\frac12p2^{-t_j}(1-w)$ by \eqref{eq:mid:standing}; if not, $a(x)$ counts the labels outside the same $n-1$ values that satisfy the $t_j=d_j$ constraints of $j$, so $a(x)\ge p2^{-t_j}(1-w)$. The same holds for $b$ with $i$ in place of $j$. Put $k=\frac12$ for an edge and $k=1$ otherwise; then $\min a\cdot\min b\ge k^2p^22^{-t_i-t_j}(1-w)^2$. The conditional expectation operator from $L^2(y_j)$ to $L^2(y_i)$ is unitarily equivalent to the matrix $\widetilde K=D_a^{-1/2}KD_b^{-1/2}\colon\ell^2(S_j)\to \ell^2(S_i)$; its top singular value is $1$, with singular vectors $\sqrt b,\sqrt a$, and the maximal correlation is its second singular value $s_2(\widetilde K)$. Since $D_a^{-1/2}(k\Jall)D_b^{-1/2}$ has rank one ($\Jall$ the all-ones matrix), \[ s_2(\widetilde K)\le\big\|D_a^{-1/2}(K-k\Jall)D_b^{-1/2}\big\|\le \frac{\|K-k\Jall\|_{\ell^2(S_j)\to\ell^2(S_i)}}{\sqrt{\min a\cdot\min b}} . \] For an edge, $K-k\Jall$ is a submatrix of the $\Fp\times\Fp$ matrix $(\Ap(\pm(x'-x))-\frac12)$, whose norm is at most $\frac{\sqrt p+1}2$ by \cref{lem:square-shift}(a), for either orientation. For a non-edge, $K-\Jall$ is minus a partial identity, of norm at most $1$. Hence, for an edge, $\rho\le2^{(t_i+t_j)/2}\frac{\sqrt p+1}{p(1-w)}=2^{(d_i+d_j-2)/2}\frac{r+r^2}{1-w}$, and for a non-edge $\rho\le2^{(d_i+d_j)/2}\frac{r^2}{1-w}$. These are $\eps_{ij}/(H_w(1-w))\le\eps_{ij}$, since $H_w(1-w)=(1+w)/(1-w)\ge1$. \end{proof} \begin{lemma}[Connectivity of pinned state spaces]\label{lem:mid:connect} In the setting of \cref{def:mid:influence}, let $w^{\rm conn}$ satisfy the second inequality of \eqref{eq:mid:standing}. For every feasible pinning $(S',s')$ that extends $(S,s)$, any two elements of $\Omega_{S',s'}$ are joined by a sequence of elements of $\Omega_{S',s'}$ in which consecutive elements differ in exactly one free coordinate. \end{lemma} \begin{proof} Every free vertex of $(S',s')$ is free for $(S,s)$, so it has degree at most $\Delta_F$. By \eqref{eq:mid:standing}, for every $t\le\Delta_F+1$ and every set of at most $2n$ excluded values containing the roots, a vertex with $t$ root constraints at distinct roots has at least $p2^{-t}(1-w^{\rm conn})>0$ admissible labels. Let $x,y\in\Omega_{S',s'}$ and let $T=y(U\setminus S')$ be the set of target labels; $|T|\le n$. \emph{Phase 1.} For each free vertex in turn, change its label to a value outside $T$ and outside all labels currently in use that satisfies its constraints with all its (currently labelled) neighbours: at most $\Delta_F$ distinct roots and at most $2n$ exclusions, so this is possible. Each step stays in $\Omega_{S',s'}$. Afterwards no free vertex carries a target label. \emph{Phase 2.} Process the free vertices $i$ one by one. Call a free vertex \emph{placed} once it carries its target label. Invariant: placed vertices carry their targets; unplaced free vertices carry labels outside $T$. Before placing $i$, change each unplaced neighbour $j\ne i$ of $i$ to a value that satisfies all constraints of $j$ with its current neighbours (including the current label of $i$), satisfies the constraint of the edge between $j$ and $i$ for the prospective label $y_i$, and avoids $T$ and all labels in use. The prospective root $y_i$ differs from every current label: pinned and placed vertices carry target labels $\ne y_i$ (injectivity of $y$), and unplaced vertices carry labels outside $T$. So there are at most $\Delta_F+1$ distinct roots and at most $2n$ exclusions, and the move is possible; the invariant is kept. Now change $i$ to $y_i$: its constraints with pinned and placed neighbours hold because $y$ is feasible, those with unplaced neighbours hold by construction, and $y_i$ is not in use. Later moves only touch unplaced vertices and respect the constraints with all current labels. When all free vertices are placed we have reached $y$. \end{proof} \begin{lemma}[Coordinate subspaces]\label{lem:mid:subspaces} In the setting of \cref{lem:mid:connect}, fix a feasible pinning $(S',s')$ that extends $(S,s)$, with free set $F'$. In $L^2(\mu_{S',s'})$ let $V_i$ ($i\in F'$) be the subspace of functions of $y_{F'\setminus\{i\}}$, and put $V_A=\bigcap_{i\in A}V_i$ for $A\subseteq F'$ ($V_\emptyset=L^2(\mu_{S',s'})$). \begin{enumerate}[label=\textup{(\roman*)}] \item $V_A$ is the space of functions of $y_{F'\setminus A}$; in particular $V_{F'}$ is the space of constants. Moreover $V_A\cap V_{A'}=V_{A\cup A'}$. \item Let $\beta,\beta'\subseteq F'$ be disjoint and nonempty, and let $\bar\eps\ge0$ be such that $\rho(y_\beta;y_{\beta'}\mid y_{U\setminus(\beta\cup\beta')}=z)\le\bar\eps$ for every feasible value $z$ of $y_{U\setminus(\beta\cup\beta')}$ that extends $s'$. Then $\cos\angle(V_\beta,V_{\beta'})\le\bar\eps$. In particular, if $w$ satisfies the first inequality of \eqref{eq:mid:standing}, then $\cos\angle(V_i,V_j)\le\eps_{ij}$ for distinct $i,j\in F'$. \item For disjoint nonempty $\beta,\beta'\subseteq F'$, $\cos\angle(V_{F'\setminus\beta'},V_{F'\setminus\beta})=\rho(y_\beta;y_{\beta'}\mid y_{S'}=s')$. \end{enumerate} \end{lemma} \begin{proof} (i) Functions of $y_{F'\setminus A}$ lie in $V_A$. Conversely let $f\in V_A$, so $f$ is unchanged by any change of one coordinate in $A$ that stays in $\Omega_{S',s'}$. For a value $u$ of $y_{F'\setminus A}$, the completions with $y_{F'\setminus A}=u$ form $\Omega_{S'\cup(F'\setminus A),(s',u)}$, which is connected by single-coordinate moves in $A$ (\cref{lem:mid:connect}, applied to this pinning, which extends $(S,s)$). So $f$ is constant there. The last statement is the definition of $V_A$. (ii) By (i), $V_\beta\cap V_{\beta'}=V_{\beta\cup\beta'}$ consists of the functions of $u=y_{F'\setminus(\beta\cup\beta')}$. Let $f\in V_\beta\ominus V_{\beta\cup\beta'}$ and $g\in V_{\beta'}\ominus V_{\beta\cup\beta'}$: $f$ is a function of $(y_{\beta'},u)$ with $\E[f\mid u]=0$, and $g$ a function of $(y_\beta,u)$ with $\E[g\mid u]=0$. Conditionally on $u$ the law is $\mu(\cdot\mid y_{U\setminus(\beta\cup\beta')}=(s',u))$, a full pinning of $U\setminus(\beta\cup\beta')$ that extends $s'$, under which $f$ is a centred function of $y_{\beta'}$ and $g$ a centred function of $y_\beta$. So $|\E[fg\mid u]|\le\bar\eps\,\E[f^2\mid u]^{1/2}\E[g^2\mid u]^{1/2}$, and averaging over $u$ with Cauchy--Schwarz gives $|\ip fg|\le\bar\eps\norm f\norm g$ (\cref{cor:cond-decorrelation}). For single vertices, \cref{lem:mid:pinpair} supplies $\bar\eps=\eps_{ij}$. (iii) By (i), $V_{F'\setminus\beta'}$ and $V_{F'\setminus\beta}$ are the functions of $y_{\beta'}$ and of $y_\beta$, and their intersection is $V_{F'}$, the constants, since $\beta\cap\beta'=\emptyset$. So the Friedrichs cosine (\cref{def:prelim:angle}) is the supremum over centred functions, which is the maximal correlation (\cref{def:prelim:maxcorr}). \end{proof} \begin{lemma}[All partial pinnings: Kassabov--Schur elimination]\label{lem:mid:allpin} In the setting of \cref{lem:mid:subspaces}, let $\mathcal P$ be a partition of $F'$ into nonempty parts and $\bar E=(\bar E_{\beta\beta'})_{\beta,\beta'\in\mathcal P}$ a symmetric matrix with nonnegative entries, zero diagonal and $\norm{\bar E}<1$, such that $\cos\angle(V_\beta,V_{\beta'})\le\bar E_{\beta\beta'}$ for all distinct $\beta,\beta'\in\mathcal P$ (for instance, by \cref{lem:mid:subspaces}(ii), if every fully pinned correlation $\rho(y_\beta;y_{\beta'}\mid y_{U\setminus(\beta\cup\beta')}=z)$ is at most $\bar E_{\beta\beta'}$). Then for all distinct $\beta,\beta'\in\mathcal P$ \[ \rho(y_\beta;y_{\beta'}\mid y_{S'}=s')\le\big[(I-\bar E)^{-1}\big]_{\beta\beta'} . \] In particular, if $w$ satisfies the first inequality of \eqref{eq:mid:standing} and $\norm{\mathcal E}<1$, then for distinct $i,j\in F'$ \[ \rho(y_i;y_j\mid y_{S'}=s')\le\big[(I-\mathcal E_{F'F'})^{-1}\big]_{ij}\le \big[(I-\mathcal E)^{-1}\big]_{ij}. \] \end{lemma} \begin{proof} For $\mathcal Y\subseteq\mathcal P$ put $V[\mathcal Y]=V_{\cup\mathcal Y}$; by \cref{lem:mid:subspaces}(i) it is the space of functions of $y_{F'\setminus\cup\mathcal Y}$, and $V[\mathcal Y]\cap V[\mathcal Y']=V[\mathcal Y\cup\mathcal Y']$. Let $M=I-\bar E$, positive definite since $\norm{\bar E}<1$. For $\mathcal Y\subseteq\mathcal P$ and distinct $\beta,\beta'\in\mathcal P\setminus\mathcal Y$ put $c_{\mathcal Y}(\beta,\beta')=\cos\angle(V[\mathcal Y\cup\{\beta\}],V[\mathcal Y\cup\{\beta'\}])$. Let $M^{(\mathcal Y)}$ be the Schur complement of $M_{\mathcal Y\mathcal Y}$ in $M$, a positive definite matrix on $\mathcal P\setminus\mathcal Y$, let $N^{(\mathcal Y)}$ be its normalization $N^{(\mathcal Y)}_{\beta\beta'}=M^{(\mathcal Y)}_{\beta\beta'}/(M^{(\mathcal Y)}_{\beta\beta}M^{(\mathcal Y)}_{\beta'\beta'})^{1/2}$, and put $e_{\mathcal Y}(\beta,\beta')=-N^{(\mathcal Y)}_{\beta\beta'}$. \emph{Claim: $0\le e_{\mathcal Y}(\beta,\beta')<1$ and $c_{\mathcal Y}(\beta,\beta')\le e_{\mathcal Y}(\beta,\beta')$.} For $\mathcal Y=\emptyset$, $e_\emptyset(\beta,\beta')=\bar E_{\beta\beta'}$, and the claim is the hypothesis. Since $N^{(\mathcal Y)}$ is positive definite with unit diagonal, its off-diagonal entries have modulus $<1$. Let $\mathcal Y'=\mathcal Y\cup\{\gamma\}$. Eliminating $\gamma$ from $N^{(\mathcal Y)}$ (Schur complements are transitive, and conjugating by a positive diagonal matrix commutes with taking Schur complements and with normalizing) gives \[ e_{\mathcal Y'}(\beta,\beta')=\frac{e_{\mathcal Y}(\beta,\beta')+e_{\mathcal Y}(\beta,\gamma)e_{\mathcal Y}(\beta',\gamma)}{\sqrt{(1-e_{\mathcal Y}(\beta,\gamma)^2)(1-e_{\mathcal Y}(\beta',\gamma)^2)}}\ \ge0 . \] On the other hand, Kassabov's inequality (\cref{thm:kassabov}) with $V_1=V[\mathcal Y\cup\{\beta\}]$, $V_2=V[\mathcal Y\cup\{\beta'\}]$, $V_3=V[\mathcal Y\cup\{\gamma\}]$, for which $V_1\cap V_3=V[\mathcal Y'\cup\{\beta\}]$ and $V_2\cap V_3=V[\mathcal Y'\cup\{\beta'\}]$, gives \[ c_{\mathcal Y'}(\beta,\beta')\le\frac{c_{\mathcal Y}(\beta,\beta')+c_{\mathcal Y}(\beta,\gamma)c_{\mathcal Y}(\beta',\gamma)}{\sqrt{(1-c_{\mathcal Y}(\beta,\gamma)^2)(1-c_{\mathcal Y}(\beta',\gamma)^2)}} , \] the denominators being positive by induction. The right side is nondecreasing in each of its three arguments on $[0,1)$; by induction on $|\mathcal Y|$, $c_{\mathcal Y}\le e_{\mathcal Y}$ entrywise, which proves the claim. Thus the cosines of the coordinate subspaces are bounded by the recursion of Gaussian elimination in $I-\bar E$. Take $\mathcal Y=\mathcal P\setminus\{\beta,\beta'\}$. By \cref{lem:mid:subspaces}(iii), $c_{\mathcal Y}(\beta,\beta')=\rho(y_\beta;y_{\beta'}\mid y_{S'}=s')$. The Schur complement of $M_{\mathcal Y\mathcal Y}$ is the inverse of the $\{\beta,\beta'\}$ block of $\mathcal Q=M^{-1}$, so $e_{\mathcal Y}(\beta,\beta')=\mathcal Q_{\beta\beta'}/\sqrt{\mathcal Q_{\beta\beta}\mathcal Q_{\beta'\beta'}}$. The Neumann series $\mathcal Q=\sum_{k\ge0}\bar E^k$ has nonnegative entries and $\mathcal Q_{\beta\beta}\ge1$; hence $e_{\mathcal Y}(\beta,\beta')\le\mathcal Q_{\beta\beta'}$. For the second statement take the partition of $F'$ into singletons and $\bar E=\mathcal E_{F'F'}$, which is admissible by \cref{lem:mid:subspaces}(ii) and has $\norm{\mathcal E_{F'F'}}\le\norm{\mathcal E}<1$; finally $(\mathcal E_{F'F'}^k)_{ij}\le(\mathcal E^k)_{ij}$ entrywise. \end{proof} \begin{proposition}[Pinned influence theorem]\label{prop:middle-negative} Let $G$ be an oriented graph with $n$ vertices, $p$ an odd prime, $\mu=\lambda_p(G)$, $(S,s)$ a feasible pinning with free set $F$, $w$ and $w^{\rm conn}$ count errors for $(G,F)$ at $p$ \eqref{eq:mid:standing}, and $\mathcal E$ the influence matrix \eqref{eq:mid:epsij}, with $\norm{\mathcal E}\le e<1$. Let $(S',s')$ be a feasible pinning that extends $(S,s)$, with free set $F'$. \begin{enumerate}[label=\textup{(\alph*)}] \item For distinct $i,j\in F'$, \[ \rho(y_i;y_j\mid y_{S'}=s')\le\big[(I-\mathcal E_{F'F'})^{-1}\big]_{ij}\le \big[(I-\mathcal E)^{-1}\big]_{ij}\le\eps_{ij}+\frac{e^2}{1-e} . \] \item For disjoint nonempty $X,Y\subseteq F'$, \[ \rho(y_X;y_Y\mid y_{S'}=s')\le\min\Big\{1,\ \norm{\mathcal E_{XY}}+\frac{e^2}{1-e}\Big\},\qquad \mathcal E_{XY}=(\eps_{uv})_{u\in X,\,v\in Y}. \] \end{enumerate} \end{proposition} \begin{proof} (a) The first two inequalities are \cref{lem:mid:allpin}. Next $(I-\mathcal E)^{-1}=I+\mathcal E+\mathcal E^2(I-\mathcal E)^{-1}$, and the last matrix is symmetric with spectrum in $\{\lambda^2/(1-\lambda):|\lambda|\le e\}\subseteq[0,e^2/(1-e)]$; so its norm, and with it every entry and the norm of every submatrix, is at most $e^2/(1-e)$. For $i\ne j$ the identity contributes nothing. (b) Apply \cref{thm:peyre-finite} (first statement) in the probability space $(\Omega_{S',s'},\mu_{S',s'})$ to the families $(y_u)_{u\in X}$ and $(y_v)_{v\in Y}$, with $\eps'_{uv}=[(I-\mathcal E)^{-1}]_{uv}\ge0$. Its hypothesis asks for $\rho(y_u;y_v\mid y_{S''}=s'')\le\eps'_{uv}$ in this space, for $S''\subseteq(X\cup Y)\setminus\{u,v\}$ and every value $s''$ of positive probability; this is $\rho(y_u;y_v\mid y_{S'\cup S''}=(s',s''))$ under $\mu$, a feasible pinning that extends $(S,s)$, so (a) supplies it. The theorem gives $\rho\le\min\{1,\opnorm{([(I-\mathcal E)^{-1}]_{uv})_{u\in X,v\in Y}}\}$. Since $X\cap Y=\emptyset$, this matrix is $\mathcal E_{XY}$ plus a submatrix of $\mathcal E^2(I-\mathcal E)^{-1}$, so its norm is at most $\norm{\mathcal E_{XY}}+e^2/(1-e)$. \end{proof} The certificates evaluate the following form, which is weaker only through the harmless factor $\sqrt{|X||Y|}\ge1$ inserted in its proof, with the Schur test for the cross block. \begin{corollary}[Schur-test form]\label{cor:influence-schur} In the setting of \cref{prop:middle-negative}, without its assumption on $\norm{\mathcal E}$, put $c_{ij}=\eps_{ij}/r$, let $q_{\rm inf}\ge\max_{i\in F}\sum_{j\in F}c_{ij}$ with $rq_{\rm inf}<1$, and for disjoint nonempty $X,Y\subseteq F'$ let \[ c_\times^2=\Big(\max_{u\in X}\sum_{v\in Y}c_{uv}\Big)\Big(\max_{v\in Y}\sum_{u\in X}c_{uv}\Big). \] Then \[ \rho(y_X;y_Y\mid y_{S'}=s')\le r\Big(c_\times+\sqrt{|X||Y|}\,\frac{rq_{\rm inf}^2}{1-rq_{\rm inf}}\Big). \] \end{corollary} \begin{proof} $\mathcal E=r(c_{ij})$ is symmetric and nonnegative, so $\norm{\mathcal E}\le rq_{\rm inf}<1$, and \cref{prop:middle-negative} applies with $e=rq_{\rm inf}$, for which $e^2/(1-e)=r\cdot rq_{\rm inf}^2/(1-rq_{\rm inf})$. The Schur test gives $\norm{\mathcal E_{XY}}\le rc_\times$. So \cref{prop:middle-negative}(b) gives the bound without the factor $\sqrt{|X||Y|}$, which is at least one. \end{proof} \begin{remark}[Uses and the certified forms]\label{rem:influence-uses} (1) The conditional influence bound \ref{it:record:upper-F2} and the row correlations $\rho_F,\rho_E$ of the twelve-label reference (\cref{lem:front12:reference}) are the bound of \cref{cor:influence-schur} with the graded count errors $w=e^-_{\Delta_F}(n)$, $w^{\rm conn}=e^-_{\Delta_F+1}(2n)$, and with $\Delta_F$, $q_{\rm inf}$ taken over the free vertices: for the rows, $X$ and $Y$ are the labels of the two outer objects and the middle object is pinned; for the layer repairs, $X$ and $Y$ are the layer halves and nothing is pinned. The certificates assert $w<\frac12$, $w^{\rm conn}<1$, $rq_{\rm inf}<1$ and that the bound is below one; the bound without $\sqrt{|X||Y|}$ is not used. (2) The frame of the upper joint stars (\cref{lem:upper-stars}) uses \cref{prop:middle-negative}(a), and (b) for disjoint vertex sets, for the empty pinning of an induced half graph, with $w=w_\Delta(p,n)$ and $w^{\rm conn}=e^-_{\Delta+1}(2n)$. (3) \emph{Monotonicity.} For fixed $G$, pinning pattern and $X,Y$, the quantities $q_{\rm inf}$, $c_\times$ and $rq_{\rm inf}^2/(1-rq_{\rm inf})$ of \cref{cor:influence-schur} are admissible functions of $r$ (\cref{lem:majorant}); so hypotheses verified at $p_0$ hold at every prime $p\ge p_0$, and the bound at $p$ is at most $r_p$ times its value divided by $r$ at $p_0$. (4) For a reflection cut with halves $U^\pm$ and the empty pinning, \cref{prop:middle-negative}(b) bounds $\rho(y_{U^+};y_{U^-})$, the centred norm of the cut coupling in its actual half marginal. \end{remark} \subsection{Recentring: from reference means to actual marginal means}\label{subsec:cuts:recentering} A coupling given by a kernel on a product of reference laws is centred in the reference, but its correlation must be measured in its own marginals. The exact identity (a) below separates the two: the cross term of the actual centring is a product of two marginal defects. It is used with a normalized kernel (part (b): the exact-support row correlations and the spectral bound for the replaced records of the one-way repairs), with an additive repair (the exact marginal cancellation \cref{lem:record:additive-cancellation}), and for differences of normalized marginals (part (c)). \begin{lemma}[Recentering]\label{lem:recentering} Let $(X,\mu_X)$ and $(Y,\mu_Y)$ be finite probability spaces with full support, and let $P_0$ denote the projections onto the mean-zero functions. \begin{enumerate}[label=\textup{(\alph*)}] \item Let $\mathfrak b$ be a bilinear form on real functions on $X$ times real functions on $Y$ with $\mathfrak b(\one,\one)=1$, and define $\varrho_L,\varrho_R$ by $\mathfrak b(f,\one)=\ip f{\varrho_L}_{\mu_X}$ and $\mathfrak b(\one,h)=\ip{\varrho_R}h_{\mu_Y}$. If $\ip f{\varrho_L}_{\mu_X}=0$ and $\ip{\varrho_R}h_{\mu_Y}=0$, then \[ \mathfrak b(f,h)=\mathfrak b(P_0f,P_0h)-\ip{\varrho_L-\one}{P_0f}_{\mu_X} \ip{\varrho_R-\one}{P_0h}_{\mu_Y}. \] \item Let $K\ge0$ be a kernel on $X\times Y$ relative to $\mu_X\otimes\mu_Y$ (operator $(Kh)(x)=\E_{y\sim\mu_Y}K(x,y)h(y)$), $z=\ip\one{K\one}>0$, and $\pi=(K/z)\,\mu_X\otimes\mu_Y$, with marginals $\varrho_L\mu_X$ and $\varrho_R\mu_Y$, so that $\varrho_L-\one=P_0K\one/z$ and $\varrho_R-\one=P_0K^*\one/z$. Suppose $|z-1|\le\eps<1$, $\norm{P_0K\one}\le M_L$, $\norm{P_0K^*\one}\le M_R$, $\norm{P_0KP_0}\le c$, $\varrho_L\ge e^{-l_L}$ and $\varrho_R\ge e^{-l_R}$. Then for $f,h$ centred under the marginals of $\pi$, \[ \frac{\ip f{Kh}}z=\frac{\ip f{P_0KP_0h}}z-\ip{\varrho_L-\one}f\ip{\varrho_R-\one}h, \] and the maximal correlation of $\pi$ is at most \[ e^{(l_L+l_R)/2}\Big(\frac c{1-\eps}+\frac{M_LM_R}{(1-\eps)^2}\Big);\qquad \text{for }l_L=l_R=l,\ M_L=M_R=M:\quad e^l\Big(\frac c{1-\eps}+\frac{M^2}{(1-\eps)^2}\Big). \] \item For two kernels $K_1,K_2$ as in (b), with $z_k=\ip\one{K_k\one}$, $m_k=P_0K_k\one$ and left marginal densities $\varrho_k=K_k\one/z_k$, \[ \varrho_1-\varrho_2=\frac{m_1-m_2}{z_1}-\frac{(z_1-z_2)\,m_2}{z_1z_2}; \] hence if $|z_k-1|\le\eps_k<1$, $\norm{m_1-m_2}\le M_D$, $|z_1-z_2|\le\Delta_z$ and $\norm{m_2}\le M_2$, then $\norm{\varrho_1-\varrho_2}\le (M_D+\Delta_zM_2/(1-\eps_2))/(1-\eps_1)$. \end{enumerate} \end{lemma} \begin{proof} (a) Write $f=f_0+a$ and $h=h_0+b$ with $f_0=P_0f$, $h_0=P_0h$ and constants $a,b$. Since $\ip\one{\varrho_L}=\mathfrak b(\one,\one)=1$ and $f_0\perp\one$, $0=\ip f{\varrho_L}=\ip{f_0}{\varrho_L-\one}+a$, so $a=-\ip{f_0}{\varrho_L-\one}$ and $\mathfrak b(f_0,\one)=\ip{f_0}{\varrho_L}=-a$; likewise $b=-\ip{\varrho_R-\one}{h_0}$ and $\mathfrak b(\one,h_0)=-b$. Hence $\mathfrak b(f,h)=\mathfrak b(f_0,h_0)+b\,\mathfrak b(f_0,\one)+a\,\mathfrak b(\one,h_0)+ab=\mathfrak b(f_0,h_0)-ab$. (b) Apply (a) to $\mathfrak b(f,h)=\ip f{Kh}/z$: then $\mathfrak b(\one,\one)=1$, $\mathfrak b(f,\one)=\ip f{K\one}/z$, so $\varrho_L=K\one/z$ and $\varrho_L-\one=P_0K\one/z$ (because $\E_{\mu_X}K\one=z$), and $\mathfrak b(P_0f,P_0h)=\ip f{P_0KP_0h}/z$; moreover $\ip{\varrho_L-\one}{P_0f}= \ip{\varrho_L-\one}f$. The centring conditions of (a) are the centring of $f$, $h$ under the marginals of $\pi$. With $z\ge1-\eps$, $\norm{\varrho_L-\one}\le M_L/(1-\eps)$ and $\norm{\varrho_R-\one}\le M_R/(1-\eps)$, so $|\int f(x)h(y)\,d\pi|=|\mathfrak b(f,h)|\le\big(\frac c{1-\eps}+\frac{M_LM_R}{(1-\eps)^2}\big)\norm f_{\mu_X}\norm h_{\mu_Y}$. Finally $\norm f^2_{\mu_X}\le e^{l_L}\E_{\mu_X}[\varrho_Lf^2]$, the squared norm of $f$ under the left marginal of $\pi$, and likewise for $h$. (c) $\varrho_k=\one+m_k/z_k$ by (b), and $m_1/z_1-m_2/z_2=(m_1-m_2)/z_1+m_2(z_2-z_1)/(z_1z_2)$. \end{proof} \begin{remark}[Instances]\label{rem:recentering-uses} (1) The exact-support correlation bound of \cref{subsec:row-anova-correlation} is (b) verbatim, with $c$ the bound of the centred strict compression and $M$ the bound of the constant images. (2) A normalized cut operator $A$ is self-adjoint with $\ip\one{A\one}=1$, so it is (b) with $z=1$, $\eps=0$ and $M_L=M_R$; if $\norm{P_0AP_0}\le gr$ and $\norm{A\one-\one}^2\le B^+r^2$ (for instance with $B^+\ge p\eps_\varrho^2/(1-gr)$ when $\norm{P_0A\one}\le\eps_\varrho$), and the actual half marginal has density at least $e^{-l}$, its correlation relative to the actual marginal is at most $e^l(gr+B^+r^2)$. This is the spectral bound for the replaced records of the one-way repairs (\ref{it:record:upper-F7}). (3) For an additive repair $d\tilde\nu=(1+f(x)+g(y))\,d\nu$ of a coupling $\nu$ of $\nu_X,\nu_Y$, apply (a) with the references $\nu_X,\nu_Y$ and $\mathfrak b(h,k)=\int hk\,d\tilde\nu$: for $h,k$ centred under the marginals $(1+u)\nu_X$, $(1+v)\nu_Y$ of $\tilde\nu$, $\int hk\,d\tilde\nu=\int h_0k_0(1+f+g)\,d\nu-\ip u{h_0}\ip v{k_0}$, which is the identity behind \cref{lem:record:additive-cancellation}. (4) Part (c) is the normalizer comparison for the upper product rows (display (PR13) in \cref{subsec:advance:product-rows}). \end{remark} \subsection{Marginals of the law itself (actual marginals)}\label{subsec:cuts:actual} Bounds are often proved in a convenient reference probability measure, while prices require norms in the marginals of the law itself---its \emph{actual marginals}. The next lemma moves between the two when the actual marginals differ from the reference by a density factor between $1-\eta$ and $1+\eta$ (the reference is called $\nu$ inside the lemma; this is a local notation, not the comparison law of Part~III). Part~(a) bounds a correlation computed in the actual marginals by one computed in the reference; part~(b) says that the operator of a difference of two records with the same actual marginal $m$ is, after the unitary change of measure, the same operator computed relative to the reference, with norm increased by at most $1/(1-\eta)$. \begin{lemma}[Actual marginals]\label{lem:record:actual-correlation} Let $\nu$ be a probability measure on a finite set $X$ with full support, let $0\le\eta<1$, and let $\mathcal H$ be a space of real functions on $X$ that contains the constants. Write $\Pi f=f-\E_\nu f$. \begin{enumerate}[label=\textup{(\alph*)}] \item Let $K\ge0$ be the density, relative to $\nu\otimes\nu$, of a probability measure on $X\times X$ with marginals $m_L=(1+\delta_L)\nu$ and $m_R=(1+\delta_R)\nu$, where $|\delta_L|,|\delta_R|\le\eta$. Suppose that $|\ip{\Pi f}{K\Pi g}_\nu|\le\kappa\norm{\Pi f}_\nu\norm{\Pi g}_\nu$ for all $f,g\in\mathcal H$. Then for all $f,g\in\mathcal H$ with $\E_{m_L}f=\E_{m_R}g=0$, \[ \Big|\int f(x)g(y)K(x,y)\,d\nu(x)\,d\nu(y)\Big|\le\frac{\kappa+\eta^2}{1-\eta} \,\norm f_{L^2(m_L)}\norm g_{L^2(m_R)} . \] \item \emph{(Density transport.)} Let $m=\psi\nu$ be a probability measure with $\psi\ge1-\eta$, let $t$ be a real function on $X\times X$, let $T$ be the operator on $L^2(\nu)$ with kernel $t$ relative to $\nu\otimes\nu$, and let $T_m$ be the operator on $L^2(m)$ with $\ip f{T_mh}_m=\int f(x)t(x,y)h(y)\,d\nu(x)\,d\nu(y)$. Let $W\colon L^2(m)\to L^2(\nu)$, $Wf=\psi^{1/2}f$, and let $M_\psi$ be multiplication by $\psi$. Then $W$ is unitary and $T_m=W^*M_\psi^{-1/2}TM_\psi^{-1/2}W$; hence $\norm{T_m}\le\norm T/\min\psi\le\norm T/(1-\eta)$, the transposed kernel gives $T_m^*$, and the symmetric and skew parts of $T_m$ are those of $T$ transported in the same way, with the same bound. \end{enumerate} \end{lemma} \begin{proof} (a) Apply \cref{lem:recentering}(a) to $\mathfrak b(f,g)=\int f(x)g(y)K(x,y)\,d\nu(x)\,d\nu(y)$: \[ \mathfrak b(f,g)=\ip{\Pi f}{K\Pi g}_\nu -\ip{\delta_L}{\Pi f}_\nu\ip{\delta_R}{\Pi g}_\nu. \] Since $\mathcal H$ contains the constants, $\Pi f,\Pi g\in\mathcal H$. The first term is bounded by the hypothesis, and the second by $\eta^2\norm{\Pi f}_\nu\norm{\Pi g}_\nu$. Finally $\norm{\Pi f}_\nu\le\norm f_\nu\le(1-\eta)^{-1/2}\norm f_{m_L}$, and likewise for $g$. (b) $\ip{Wf}{Wh}_\nu=\E_\nu[\psi fh]=\ip fh_m$, and $W$ is onto since $\psi>0$. For $f,h\in L^2(m)$, $\ip f{T_mh}_m=\ip f{Th}_\nu=\ip{M_\psi^{-1/2}Wf}{TM_\psi^{-1/2}Wh}_\nu$, which is the identity, and $\norm{M_\psi^{-1/2}}^2=1/\min\psi$. The adjoint statement is the symmetry of the defining formula. \end{proof} Part (a) is the exactly normalized case of the recentering \cref{lem:recentering}(b) ($z=1$, $\eps=0$, $M_L,M_R\le\eta$, $e^{l}=1/(1-\eta)$), restricted to a space $\mathcal H$. It bounds the centred norm of a coupling in its actual marginals when only its centred norm in a nearby reference is known. \paragraph{Positive quadratic tilts.} A positive reweighting of a symmetric kernel by a square changes its marginal. The next lemma bounds the new mass, the centred part of the new marginal and its pointwise range in terms of a few operator norms of the pointwise products of the kernel with the scores, where $\eta_j$ are arbitrary real functions on $X\times X$. \begin{lemma}[Marginals of a positive quadratic tilt]\label{lem:tilt-marginals} Let $(X,\nu)$ be a finite probability space with full support and $K\ge0$ a symmetric kernel on $X\times X$ with $\E_{\nu\otimes\nu}K=1$, marginal density $m=K\one>0$, $\sup m/\inf m\le R$ and $\norm{m-\one}_\nu\le\delta_0$. Let $\eta_0,\eta_1,\eta_2$ be real functions on $X\times X$ that are permuted among themselves by $(x,x')\mapsto(x',x)$, let $\bar\eta=\frac13\sum_j\eta_j$, and let $V=\frac13\sum_j\eta_j^2$ or $V=\bar\eta^2$. Write $K_{\bar\eta}=K\circ\bar\eta$ and $K_V=K\circ V$ for the pointwise products, and use the same letters for their operators on $L^2(\nu)$. For constants $c_V,e,\ell,h,c,b\ge0$ suppose \[ \norm{K_V-c_VK}\le e,\quad\norm{P_0K_{\bar\eta}\one}_\nu\le\ell,\quad |\ip\one{K_{\bar\eta}\one}_\nu|\le h,\quad|K_{\bar\eta}\one|\le c\,K\one,\quad |\eta_j|\le b\ \text{on}\ \{K>0\}. \] For $\ulaw\ge0$ put $s=1+c_V\ulaw^2$, and assume $\ulaw c<1$ and $z=s-2\ulaw h-\ulaw^2e>0$. Then $T=(K+2\ulaw K_{\bar\eta}+\ulaw^2K_V)/Z$, with $Z$ the $\nu\otimes\nu$-mass of the numerator, is a symmetric nonnegative kernel of mass one, and \[ Z\ge z,\qquad\norm{T\one-\one}_\nu\le\frac{s\delta_0+2\ulaw\ell+\ulaw^2e}z, \qquad\frac{\sup T\one}{\inf T\one}\le R\,\frac{(1+\ulaw b)^2}{(1-\ulaw c)^2}. \] If $T_1,\dots,T_n$ are symmetric nonnegative kernels of mass one on finite probability spaces $(X_i,\nu_i)$ with $\norm{T_i\one-\one}\le\delta_i$ and $\sup T_i\one/\inf T_i\one\le R_i$, then $T=\bigotimes_iT_i$ has range ratio at most $\prod_iR_i$ and marginal chi-square $\norm{T\one-\one}^2\le\prod_i(1+\delta_i^2)-1$. \end{lemma} \begin{proof} Put $w=1+2\ulaw\bar\eta+\ulaw^2V$, so that the numerator is $K\circ w$. In both cases $V\ge\bar\eta^2$ (for the mean of the squares by the Cauchy--Schwarz inequality), so $w\ge(1+\ulaw\bar\eta)^2\ge0$; the kernel $T$ is nonnegative, and it is symmetric because $K$, $\bar\eta$ and $V$ are. \emph{Mass.} $Z=\ip\one{K\one}+2\ulaw\ip\one{K_{\bar\eta}\one} +\ulaw^2\ip\one{K_V\one}$, with $\ip\one{K\one}=1$, $\ip\one{K_{\bar\eta}\one}\ge-h$, and $\ip\one{K_V\one}\ge c_V-e$ because $\ip\one{(K_V-c_VK)\one}\ge-e$. So $Z\ge s-2\ulaw h-\ulaw^2e=z>0$. \emph{Centred marginal.} $T\one$ has mean one, so \[ T\one-\one=\frac1Z\,P_0\big(sK\one+2\ulaw K_{\bar\eta}\one +\ulaw^2(K_V-c_VK)\one\big), \] with $\norm{P_0K\one}=\norm{m-\one}\le\delta_0$, $\norm{P_0K_{\bar\eta}\one}\le\ell$ and $\norm{P_0(K_V-c_VK)\one}\le\norm{K_V-c_VK}\le e$, since $P_0$ is a contraction and $\norm\one=1$. \emph{Range.} $(T\one)(x)=m(x)\,\E_K[w\mid x]/Z$, where $\E_K[\cdot\mid x]$ is the average in $x'$ against the probability $K(x,x')\,d\nu(x')/m(x)$; thus $K_{\bar\eta}\one=m\,\E_K[\bar\eta\mid x]$ and $|\E_K[\bar\eta\mid x]|\le c$. By conditional Jensen, \[ \E_K[w\mid x]\ge\E_K[(1+\ulaw\bar\eta)^2\mid x] \ge\big(1+\ulaw\E_K[\bar\eta\mid x]\big)^2\ge(1-\ulaw c)^2, \] and on $\{K>0\}$, $w\le(1+\ulaw b)^2$ in both cases (for the mean of the squares, $w=\frac13\sum_j(1+\ulaw\eta_j)^2$). The common factor $1/Z$ cancels from the ratio. \emph{Products.} The marginal density of $\bigotimes_iT_i$ is $\bigotimes_iT_i\one$, so its range ratio is the product of the ratios, and, every $T_i\one$ having mean one, its chi-square is $\prod_i(1+\norm{T_i\one-\one}^2)-1$ (\cref{lem:sector}(f)). \end{proof} \Cref{prop:root-chamber} applies the lemma to the positive roots of the late middle pieces (\cref{def:positive-root}), with $\eta_j=\Hs j$ and $c_V=1$ for the mean of the individual squares, and the parameters of the selected laws. The square-of-the-mean option is a second instance of the same identity. In addition, \cref{lem:record:root-marginal}(iv) uses its product clause for the range ratio and the marginal chi-square of a block of such primes. \subsection{Restriction to an injectivity event}\label{subsec:cuts:restriction} Conditional row laws are first computed against a product of laws on the allowed label sets, in which the labels of one row are independent, and then restricted to the event that they are distinct. The next lemma transfers the three numbers that the spectral and correlation estimates need (the centred compression, the constant image and the total mass) through such a restriction. \begin{lemma}[Restriction to an injectivity event]\label{lem:restriction} Let $(X,\lambda_X)$ and $(Y,\lambda_Y)$ be finite probability spaces with full support, $I_X\subseteq X$ and $I_Y\subseteq Y$ nonempty events, $P_X=\lambda_X(I_X)$, $P_Y=\lambda_Y(I_Y)$, and $\mu_X=\lambda_X(\cdot\mid I_X)$, $\mu_Y=\lambda_Y(\cdot\mid I_Y)$. For a kernel $S$ on $X\times Y$ let $T_S\colon L^2(\lambda_Y)\to L^2(\lambda_X)$, $T_Sh(x)=\E_{y\sim\lambda_Y}S(x,y)h(y)$, and let $S_\mu\colon L^2(\mu_Y)\to L^2(\mu_X)$ be the operator with kernel $S|_{I_X\times I_Y}$ relative to $\mu_X\otimes\mu_Y$. Let $\iota_Xf=\one_{I_X}f/\sqrt{P_X}$ ($f$ extended by zero) and similarly $\iota_Y$ (these $\iota_X,\iota_Y$ are embeddings, not the reserved cut $\iota$). \begin{enumerate}[label=\textup{(\alph*)}] \item $\iota_X\colon L^2(\mu_X)\to L^2(\lambda_X)$ is an isometry that maps $\mu_X$-centred functions to $\lambda_X$-centred functions, $\iota_X^*g=\sqrt{P_X}\,g|_{I_X}$, and $\iota_X\one=\sqrt{P_X}\one+v_X$ with $v_X$ centred and $\norm{v_X}=\sqrt{1-P_X}$; likewise for $Y$. Moreover $S_\mu=\iota_X^*T_S\iota_Y/\sqrt{P_XP_Y}$. \item With $P_0$ the projections onto mean-zero functions, $\norm{S_\mu}\le\norm{T_S}/\sqrt{P_XP_Y}$ and $\norm{P_0S_\mu P_0}\le\norm{P_0T_SP_0}/\sqrt{P_XP_Y}$. Let $M'_X$ be the supremum of $|\ip{\iota_Xf}{T_S\one}|$ over $\mu_X$-centred $f$ of norm one; thus $M'_X\le\norm{P_0T_S\one}$. Then \[ \norm{P_0S_\mu\one}\le\frac{M'_X}{\sqrt{P_X}}+\norm{P_0T_SP_0} \sqrt{\frac{1-P_Y}{P_XP_Y}}, \] the same holds with $X,Y$ exchanged for $S_\mu^*$, and \[ \big|\ip\one{S_\mu\one}-\ip\one{T_S\one}\big|\le\norm{P_0T_S^*\one} \sqrt{\frac{1-P_Y}{P_Y}}+\norm{P_0T_S\one}\sqrt{\frac{1-P_X}{P_X}} +\norm{P_0T_SP_0}\sqrt{\frac{(1-P_X)(1-P_Y)}{P_XP_Y}} . \] \item In particular, if $P_X,P_Y\ge I_0>0$ and $C$ bounds $\norm{P_0T_S\one}$, $\norm{P_0T_S^*\one}$ and $\norm{P_0T_SP_0}$ (for instance $C\ge\norm{T_{S-a}}$ for some constant kernel $a$), then $\norm{P_0S_\mu P_0}\le\norm{P_0T_SP_0}/I_0$, $\norm{P_0S_\mu\one}\le M'_X/\sqrt{I_0}+C\sqrt{1-I_0}/I_0\le(M+C\sqrt{1-I_0})/I_0$ for every $M\ge M'_X$, and \[ \big|\ip\one{S_\mu\one}-a_0\big|\le\frac{Z+C\big(2\sqrt{1-I_0}+1-I_0\big)}{I_0} \qquad\text{whenever }\big|\ip\one{T_S\one}-a_0\big|\le Z . \] \item If $\lambda_X$ is a product of laws on $\Fp$ indexed by an $m$-element set, each with density at most $\kappa$ relative to the uniform law, and $I_X$ is the event that the $m$ coordinates are distinct, then $P_X\ge1-\binom m2\kappa/p$. \end{enumerate} \end{lemma} \begin{proof} (a) $\norm{\iota_Xf}^2_{\lambda_X}=\E_{\lambda_X}[\one_{I_X}f^2]/P_X=\E_{\mu_X}f^2$ and $\E_{\lambda_X}\iota_Xf=\sqrt{P_X}\E_{\mu_X}f$. For the adjoint, $\ip{\iota_Xf}g_{\lambda_X}=\E_{\lambda_X}[\one_{I_X}fg]/\sqrt{P_X}=\sqrt{P_X}\,\E_{\mu_X}[fg]$. Put $v_X=\one_{I_X}/\sqrt{P_X}-\sqrt{P_X}\one$; then $\E v_X=0$ and $\norm{v_X}^2=1-2P_X+P_X=1-P_X$. Finally $\ip f{S_\mu h}_{\mu_X}=\E_{\lambda_X\otimes\lambda_Y}[\one_{I_X}f\,S\,\one_{I_Y}h]/(P_XP_Y) =\ip{\iota_Xf}{T_S\iota_Yh}/\sqrt{P_XP_Y}$. (b) The first two bounds follow from (a), since $\iota_X,\iota_Y$ are isometries preserving centring and $\ip{\iota_Xf}{T_S\iota_Yh}=\ip{\iota_Xf}{P_0T_SP_0\iota_Yh}$ for centred $f,h$. For a centred unit $f$, \[ \ip f{S_\mu\one}=\frac{\ip{\iota_Xf}{T_S(\sqrt{P_Y}\one+v_Y)}}{\sqrt{P_XP_Y}} =\frac{\ip{\iota_Xf}{T_S\one}}{\sqrt{P_X}}+\frac{\ip{\iota_Xf}{P_0T_SP_0v_Y}}{\sqrt{P_XP_Y}}, \] and $|\ip{\iota_Xf}{T_S\one}|=|\ip{\iota_Xf}{P_0T_S\one}|\le\norm{P_0T_S\one}$. Expanding $\ip{\iota_X\one}{T_S\iota_Y\one}/\sqrt{P_XP_Y}$ in the same way gives $\ip\one{S_\mu\one}=\ip\one{T_S\one}+\ip{P_0T_S^*\one}{v_Y}/\sqrt{P_Y} +\ip{v_X}{P_0T_S\one}/\sqrt{P_X}+\ip{v_X}{P_0T_SP_0v_Y}/\sqrt{P_XP_Y}$. (c) Insert $P_X,P_Y\ge I_0$, $\sqrt{1-P}\le\sqrt{1-I_0}$ and $1/\sqrt{I_0}\le1/I_0$ in (b): the last display of (b) is at most $C(2\sqrt{1-I_0}/\sqrt{I_0}+(1-I_0)/I_0)\le C(2\sqrt{1-I_0}+1-I_0)/I_0$, and $|\ip\one{T_S\one}-a_0|\le Z\le Z/I_0$. The three compressions do not change when a constant kernel is added to $S$, since $T_a\one=a\one$ and $T_aP_0=0$. (d) Two independent coordinates with laws $\lambda_i,\lambda_j$ of density at most $\kappa$ coincide with probability $\sum_x\lambda_i(x)\lambda_j(x)\le\max_x\lambda_j(x)\le\kappa/p$. Take a union bound over the $\binom m2$ pairs. \end{proof} In the upper product rows the lemma is applied to the star part of a conditional kernel, with $a_0=0$ for its mean (the normalizer errors and the centred constant images of \cref{subsec:push:layer72product}), and to the difference of the $F$ and $E$ star parts, with $C$ the sum of their full-operator bounds (display (PR12) in \cref{subsec:advance:product-rows}); in the exact-support row correlations of \cref{subsec:row-anova-correlation}, part (b) gives the bound of the centred strict compression. \subsection{Kernels depending on few coordinates}\label{subsec:cuts:projection} Many kernels below depend on only a few of the labels. The next lemma says their operator norm can then be computed using those labels alone, up to explicit factors comparing the true marginals with the uniform ones. \begin{lemma}[Projected kernels]\label{lem:record:projection} Let $\nu$ be a probability measure on a finite product $\Omega=\prod_{i\in\Lambda}\Omega_i$; for $I\subseteq\Lambda$ let $\nu_I$ be the law of $x_I=(x_i)_{i\in I}$ under $\nu$, $\upsilon_I$ the uniform law on $\Omega_I=\prod_{i\in I}\Omega_i$, and $\varrho_I\ge\max d\nu_I/d\upsilon_I$. \begin{enumerate}[label=\textup{(\alph*)}] \item Let $I,J\subseteq\Lambda$ be nonempty and let $\kappa$ be a function of $(x_I,y_J)$ only. The norm of the operator with kernel $\kappa$ on $L^2(\nu)$ (relative to $\nu\otimes\nu$) equals the norm of the operator with kernel $\kappa$ from $L^2(\nu_J)$ to $L^2(\nu_I)$ (relative to $\nu_I\otimes\nu_J$), and is at most $(\varrho_I\varrho_J)^{1/2}$ times the norm of $\kappa$ from $L^2(\upsilon_J)$ to $L^2(\upsilon_I)$. In particular, if a probability $\lambda$ on $\Omega$ has density at most $H$ relative to the uniform law, every kernel has norm on $L^2(\lambda)$ at most $H$ times its norm for independent uniform labels. \item Let $\Omega=\Fp^{\{0,1,2\}}$. For the uniform law $\nu_F$ on ordered triples of distinct labels with $x_2-x_0\in\Qsq$ (the law $\lambda_p$ of the graph on $\{0,1,2\}$ with the single edge $0\to2$) one may take $\varrho_I=1$ for one label, $\varrho_{\{0,2\}}=2/(1-q)$, $\varrho_{\{0,1\}}=\varrho_{\{1,2\}}=1/(1-2q)$ and $\varrho_{\{0,1,2\}}=2/((1-q)(1-2q))$. For the uniform law $\nu_E$ on ordered triples of distinct labels one may take $\varrho_I=1$ for one label, $\varrho_I=1/(1-q)$ for two labels and $\varrho_{\{0,1,2\}}=1/((1-q)(1-2q))$. \end{enumerate} \end{lemma} \begin{proof} (a) The operator factors as $\iota_I\widetilde\kappa\,\iota_J^*$, where $\iota_I\colon L^2(\nu_I)\to L^2(\nu)$ is the isometric embedding of functions of $x_I$, $\iota_J^*$ is the conditional expectation onto functions of $x_J$, and $\widetilde\kappa$ is the operator with kernel $\kappa$ from $L^2(\nu_J)$ to $L^2(\nu_I)$; since $\iota_I$ is isometric and $\iota_J^*\iota_J$ is the identity, the norms agree. If $\psi_I$ is the density of $\nu_I$, then $\ip\varphi{\widetilde\kappa\phi}=\E_{\upsilon_I\otimes\upsilon_J}[\varphi\psi_I\, \kappa\,\phi\psi_J]$, and $\E_{\upsilon_I}[\varphi^2\psi_I^2]\le\varrho_I \norm\varphi_{\nu_I}^2$. The last statement is the case $I=J=\Lambda$. (b) Every coordinate of $\nu_F$ and of $\nu_E$ is uniform, by translation invariance. $\nu_F$ has $p(p-1)(p-2)/2$ equally likely triples, so its density is $2p^2/((p-1)(p-2))$. The pair $(x_0,x_2)$ is uniform on the $p(p-1)/2$ directed pairs, of density $2p/(p-1)$. Given distinct $x_0,x_1$ there are at most $(p-1)/2$ completions $x_2$, and given distinct $x_1,x_2$ at most $(p-1)/2$ completions $x_0$, which gives the density bound $p/(p-2)$. Under $\nu_E$ every pair is uniform on distinct pairs, of density $p/(p-1)$, and the triple has density $p^2/((p-1)(p-2))$. \end{proof} With (a), a kernel norm computed for independent uniform labels, for instance by the kernel bound of \cref{lem:matching:kernel}, transfers to every such law at the cost of the displayed density factors. \subsection{Conditional laws given the middle label, under a change of reference}\label{subsec:cuts:rows} The five-type completions (\cref{lem:five-type}) need, at each label of the middle object, a bound for the fold and matching row operators relative to one common reference law of the outer rows. The fold row law has its own marginals; the next lemma bounds the effect of the change of reference. \begin{lemma}[Row comparison]\label{lem:row-comparison} Let $\nu$ be a probability measure on a finite set $X$ with full support, $\pi$ a probability measure on $X\times X$ with marginals $\pi_L=r_L\nu$ and $\pi_R=r_R\nu$ and maximal correlation $\rho_\pi$, and $T$ the operator on $L^2(\nu)$ with kernel $d\pi/d(\nu\otimes\nu)$. Let $H_L\ge\max r_L$, $H_R\ge\max r_R$, $v_L\ge\norm{r_L-\one}_\nu$ and $v_R\ge\norm{r_R-\one}_\nu$. \begin{enumerate}[label=\textup{(\alph*)}] \item For real $f,h\in L^2(\nu)$ with $\nu$-means $a,b$ and centred parts $f_0,h_0$, \begin{align*} \ip f{(T-\Jproj)h}_\nu&=\operatorname{Cov}_\pi(f(x),h(y))+(\E_{\pi_L}f-a)\E_{\pi_R}h +a(\E_{\pi_R}h-b)\\ &=a\ip{r_R-\one}{h_0}+b\ip{r_L-\one}{f_0}+\ip{f_0}{Th_0}, \end{align*} so the two mean terms are at most $v_R|a|\norm{h_0}$ and $v_L|b|\norm{f_0}$, and the fluctuation term satisfies $|\ip{f_0}{Th_0}|\le(\sqrt{H_LH_R}\,\rho_\pi+v_Lv_R)\norm{f_0}\norm{h_0}$. Hence \[ \norm{T-\Jproj}\le\sqrt{H_LH_R}\,\rho_\pi+v_L\min\{\sqrt{H_R},1+v_R\}+v_R\le \sqrt{H_LH_R}\,\rho_\pi+v_L+v_R+v_Lv_R . \] \item If $H_0\ge1$ and $m\ge0$ satisfies $m\le H_0$ and $|m-1|\le H_0-1$ (for instance $m\in[1/H_0,H_0]$), then $\norm{mT-\Jproj}\le H_0(\sqrt{H_LH_R}\,\rho_\pi+v_L+v_R+v_Lv_R)+H_0-1$. \item Let $X=\prod_{p\in B}X_p$, $\nu=\bigotimes_p\nu_p$ and $\pi=\bigotimes_p\pi_p$. Then $r_L=\prod_pr_{L,p}$, $1+\norm{r_L-\one}^2=\prod_p(1+\norm{r_{L,p}-\one}^2)$, likewise for $r_R$, and $\rho_\pi=\max_p\rho_{\pi_p}$. A density $\rho$ with $\E_\nu\rho=1$ and values in $[l,u]$ has $\norm{\rho-\one}^2\le(u-1)(1-l)$. \end{enumerate} \end{lemma} \begin{proof} (a) $\ip f{Th}_\nu=\E_\pi[f(x)h(y)]$ and $\ip f{\Jproj h}_\nu=ab$, which gives the first expression. For the second, $\E_\pi[f(x)h(y)]=ab+a\E_{\pi_R}h_0+b\E_{\pi_L}f_0+\E_\pi[f_0(x)h_0(y)]$, with $\E_{\pi_R}h_0=\ip{r_R}{h_0}=\ip{r_R-\one}{h_0}$ and likewise for $f_0$. Next $\E_\pi[f_0(x)h_0(y)]=\operatorname{Cov}_\pi(f_0,h_0)+\E_{\pi_L}f_0\,\E_{\pi_R}h_0$; the covariance is at most $\rho_\pi\norm{f_0}_{\pi_L}\norm{h_0}_{\pi_R}\le \rho_\pi\sqrt{H_LH_R}\norm{f_0}_\nu\norm{h_0}_\nu$, and the product of the means at most $v_Lv_R\norm{f_0}\norm{h_0}$. For the norm bound (the kernel is real, so real $f,h$ suffice) use the first expression: the covariance term is bounded in the same way, with $f,h$ in place of $f_0,h_0$; $|\E_{\pi_L}f-a|=|\ip{r_L-\one}f|\le v_L\norm f$, $|\E_{\pi_R}h|\le\min\{\norm h_{\pi_R},\norm{r_R}\norm h\}\le \min\{\sqrt{H_R},1+v_R\}\norm h$ (as $\norm{r_R}^2=1+\norm{r_R-\one}^2$), $|a|\le\norm f$ and $|\E_{\pi_R}h-b|\le v_R\norm h$. (b) $\norm{mT-\Jproj}\le m\norm{T-\Jproj}+|m-1|\norm\Jproj$. (c) The marginal densities of a product are products, and the identity for $\norm{r_L-\one}^2$ is \cref{lem:sector}(f). Maximal correlations of product couplings are maxima over the factors by \cref{lem:sector}(c). Finally $(u-r)(r-l)\ge0$ gives $\E r^2\le(u+l)\E r-ul=u+l-ul$, so $\E(r-1)^2\le(u-1)(1-l)$. \end{proof} \begin{remark}[Instances]\label{rem:row-comparison-uses} In the applications $\nu$ is the common conditional reference of the outer rows at a fixed middle label, $\pi$ the conditional fold row law, $\rho_\pi\le\rho_F$ a bound for its maximal correlation (\cref{cor:influence-schur}, or in the upper rows its minimum with \eqref{eq:row-anova-actual}), and $m$ the density of the fold middle law relative to the common middle law at that label. (1) On a block of $n_B$ primes with per-prime marginal densities in $[R^{-1},R]$ and $m=1$, (c) gives $H_L,H_R\le R^{n_B}$ and $v^2\le\exp(n_B(R-1)^2)-1$, whence the row coefficient $fr=R^{n_B}\rho_F+2v+v^2$ of the twelve-label reference, with $R$ the density-ratio bound $R_j$ of \cref{lem:record:class-three}(iii) (\cref{lem:front12:reference}); a matching row has exact marginals, so $hr=\rho_E$. (2) With pointwise log-ratio bounds $|\log r_L|,|\log r_R|\le\ell_{\rm mar}$ and $|\log m|\le\ell_{\rm mid}$, (a) and (b) give $e^{\ell_{\rm mid}}(e^{\ell_{\rm mar}}\rho_F+e^{2\ell_{\rm mar}})-1$, the common-reference fold row bound of the two-layer rows. (3) With middle ratio $H$, pointwise marginal inflation $R_{\rm m}$ and chi-square defect $\upsilon$, (b) gives the full-norm coefficient $f=[H(R_{\rm m}\rho_F+2\upsilon+\upsilon^2)+H-1]/r$ of the rows at large primes (\cref{lem:tail-prices}), the alternative to their Schur coefficient (\ref{it:record:upper-F5}(b)). (4) With $|r_L-1|,|r_R-1|\le c_0$ pointwise, the first bound of (a) gives $\rho_\pi(1+c_0)+c_0\sqrt{1+c_0}+c_0$. (5) In the rows of the upper bands the fold and matching rows are bounded jointly on the actual matching chart (\cref{lem:joint-rows,cor:joint-row-split}) and enter the completions through \cref{lem:five-type}(f); part (b) is not used there. \end{remark} \paragraph{Consequences and what to read next.} The labellings, the count errors and the sequential counts (\cref{def:graphs:labeling}, \eqref{eq:graphs:et}, \eqref{eq:graphs:graded}, \cref{lem:extension}, \cref{lem:graphs:sequential}); maximal correlation, Friedrichs angles, Kassabov's angle inequality, Peyre's tensorization (first statement) and conditional decorrelation (\cref{def:prelim:maxcorr,def:prelim:angle,thm:kassabov,thm:peyre-finite,cor:cond-decorrelation}); the norm of the square-shift matrices (\cref{lem:square-shift}(a)); square-affine invariance and uniform marginals (\cref{lem:marginals}); the Markov tensor maximum, product densities and the tensor spectrum (\cref{lem:sector}(c),(f),(g)); and admissible majorants and block budgets (\cref{lem:majorant}). Three standard facts are used without statement: the Schur product theorem, conditional Jensen, and the Rayleigh quotient characterization of the largest eigenvalue. \space % End sections/13_cuts_correlations % Begin sections/14_spectral \section{Spectral criteria for cut operators}\label{sec:spectral} \paragraph{What this section proves and how to read it.} This section proves that a lower bound $A_p\succeq -gp^{-1/2}I$ for a cut operator (the normalized cut operator $\Op$ of \cref{lem:spec:cutkernel}), for all $p\ge p_0$, can be verified by one finite positive-semidefiniteness test at $p_0$. Two routes are given: Route~A via conditional laws of the opposite half, centring at the half-law mean; Route~B via explicit uniform averages over allowed label sets, needing no completed law. A third method computes star-shaped parts exactly in a fixed invariant half law. \emph{Centring at the half-law mean} means subtracting the mean under the half law itself, not under a uniform model; a \emph{matrix part} is a block of an operator matrix, never a prime block. Inputs: \cref{sec:cuts,sec:dl,sec:extraction}. Outputs: the spectral caps used for completions in Part~V. A first reading should follow the statements of the two criteria and \cref{subsec:spec:thresholds}; Fourier and coupling details are reference material. The list of Part~V cuts using each route is in \cref{sec:design-walk}; it is not needed to read the criteria. Both routes also bound the mean-zero compression and give $\Op\preceq(1+O(1/p))I$ ($\Op$ and $r=p^{-1/2}$ are as in the Conventions paragraph below), which is what allows tensorisation over a prime block. Cut codes such as L20 denote specific mirror symmetries of the twelve- or $72$-label graphs; each is expanded where it is first used in Part~V and need not be memorised here. \paragraph{The method.} The criteria split $L^2(\mu)$ into the constants, the \emph{degree-one space} $\mathcal V$ of sums of mean-zero functions of one label, and the rest. Fourier analysis diagonalizes $\Op$ on $\mathcal V$: on the mode $\xi$ it acts as $r\Azero(\xi)$ up to an error of operator norm $O(r^2)$, quantified in \cref{subsec:spec:degone}, where $\Azero(\xi)=\chi(\xi)\eps_G\Delta^E$ is the signed matrix of the cross edges (\cref{subsec:spec:fourier,subsec:spec:degone}). The coupling of $\mathcal V$ to the rest is controlled by a Gram matrix of the conditional densities of one opposite label; these densities lie within the factor $R'_k$ of uniform on the explicit allowed sets $\Phi_k(x)$ (\cref{def:coupling-data}) and are compared entrywise with an explicit model matrix (\cref{subsec:spec:coupling,subsec:spec:completion-variance}). On the rest the cross kernel is expanded in characters of sets of cross pairs (\cref{subsec:spec:perp}). Centring the test function at its mean under the half law makes the empty set and every star vanish exactly there (\cref{subsec:spec:centring}). What remains are the nonstar sets, which are of second order and are bounded by the extraction lemma and by bounding the terms with a repeated label separately (\cref{lem:matching:extractionk,lem:oct24-collision}). A Schur complement over the two remaining blocks gives the finite test (\cref{subsec:spec:routeA}). Route~B (\cref{subsec:spec:routeB}) works with explicit Markov stars instead of the conditional law of the opposite half, and therefore needs no information on the completed cut law. Every error term is an admissible function of $r=p^{-1/2}$, so one exact test at a threshold covers all larger primes (\cref{subsec:spec:thresholds}). Class one ($p\equiv1\pmod4$) needs the extra terms $\Hmat^{\rm cov}$ and $\eps_{\rm par}$, collected in \cref{subsec:advance:parity}. When the half law is one explicit invariant law, the star part can instead be computed exactly in that law (\cref{subsec:spec:actual-stars}); this is how the cut L20 of the uniform middle root, the cuts of the positive roots and the observed caps of the upper range are bounded. \paragraph{Conventions.} Throughout, $(G,\vartheta,U^+,\mathfrak o)$ are spectral data (\cref{def:spec:data}; here $\vartheta$ is the cut involution, not the density exponent $\vartheta$ of the closings), with the notation of \cref{subsec:cuts:data}: $n=|U^+|$, the cross signs $\varsigma_{jk}$, $N(k)$, $r_k=|N(k)|$, the internal degrees $d^0_k$, $d_k=d^0_k+r_k$, $\Delta=\max_kd_k$, $\Delta^+=\max_kd^0_k$, the cross pairs $E_\times$, $m_\times=|E_\times|$, the deletion degrees $t_i$ and $\Rcut$. Let $p$ be an odd prime with $e_\Delta(p,2n)<1$, $r=p^{-1/2}$ and $q=1/p$. Then $\mathcal I^+=\operatorname{Inj}_p(G^+)$, $\mu=\lambda_p(G^+)$ is the half law, $\lambda=\lambda_p(G)$, $m_p$ is the actual half marginal, $K$ is the cut kernel \eqref{eq:spec:K}, $Z=\E_{\mu\otimes\mu}K$, $\varrho=dm_p/d\mu=\Op\one$ and $Q(F)=\ip F{\Op F}_\mu$ (\cref{lem:spec:cutkernel}). Inner products are conjugate-linear in the first variable. $\Op$ has a real symmetric kernel, so its quadratic form is determined by real functions. $P_0=I-\Jproj$ is the projection onto the $\mu$-mean-zero functions, and $u\otimes v$ is the operator $f\mapsto\ip vf_\mu u$. The class of $p$ is $\mathfrak c\in\{1,3\}$, $p\equiv\mathfrak c\pmod4$, and $\one_{p\equiv1(4)}$ is the indicator of class one. Every error term below is an explicit expression in $p$; replacing $p$ by $r^{-2}$ makes it a function of $r$, and \emph{admissible} means admissible in the sense of \cref{def:majorant}, that is, nondecreasing in $r$. \subsection{Single-variable Fourier analysis}\label{subsec:spec:fourier} On $L^2(\Fp)$ we use the uniform probability, with inner product $\ip fg=\E_a\overline{f(a)}g(a)$. The characters $e_\xi(a)=\ee{\xi a/p}$ ($\xi\in\Fp$) form an orthonormal basis, $\hat g(\xi)=\ip{e_\xi}g$, and $L^2_0(\Fp)$ is the space of mean-zero functions. Let $\eps_G=G_\chi/\sqrt p$ (\cref{thm:gauss}\ref{it:gauss:quad}), let $C$ be the \emph{Gauss operator} $(Ch)(a)=\E_{b\in\Fp}\chi(b-a)h(b)$ (the Paley operator $P$ of \cref{lem:square-shift}, written $C$ here and in \cref{sec:extraction}), and for $\varsigma\in\{\pm1\}$ let $(C_\varsigma h)(a)=\E_b\chi(\varsigma(b-a))h(b)$. \begin{lemma}[The Gauss operator]\label{lem:spec:gauss} $Ce_\xi=c_\xi e_\xi$ with $c_0=0$ and $c_\xi=\chi(\xi)\eps_Gr$ for $\xi\ne0$. Moreover $\eps_G^2=\chi(-1)$, so $\eps_G\in\{\pm1\}$ if $p\equiv1\pmod4$ and $\eps_G\in\{\pm i\}$ if $p\equiv3\pmod4$; $|c_\xi|=r$ for $\xi\ne0$; $\norm C=r$; $C\one=C^*\one=0$; $\overline{c_\xi}=c_{-\xi}=\chi(-1)c_\xi$; and $C_\varsigma=\chi(\varsigma)C$. \end{lemma} \begin{proof} $(Ce_\xi)(a)=\E_b\chi(b-a)\ee{\xi b/p}=e_\xi(a)\,p^{-1}\sum_t\chi(t)\ee{\xi t/p}$, and by \cref{thm:gauss}\ref{it:gauss:quad} the last sum is $\chi(\xi)G_\chi$ for every $\xi\in\Fp$. So $c_\xi=\chi(\xi)G_\chi/p=\chi(\xi)\eps_Gr$. By the same part of \cref{thm:gauss}, $\eps_G^2=\chi(-1)$ and $|\eps_G|=1$, so $|c_\xi|=r$ for $\xi\ne0$; $\overline{G_\chi}=\chi(-1)G_\chi$ gives $\overline{c_\xi}=\chi(-1)c_\xi$, and $\chi(-\xi)=\chi(-1)\chi(\xi)$ gives $c_{-\xi}=\chi(-1)c_\xi$. Since $C$ is the Paley operator $P$, \cref{lem:square-shift}(c) gives $\norm C=r$ and $C\one=C^*\one=0$. Finally $\chi(\varsigma(b-a))=\chi(\varsigma)\chi(b-a)$. \end{proof} The group $\mathrm{Aff}_p=\{z\mapsto az+c:\ a\in\Qsq,\ c\in\Fp\}$ of square-affine maps acts diagonally on $\Fp^2$ and on $\Fp^W$ for every finite set $W$. Its orbits on $\Fp^2$ are the diagonal, $\Om=\{(a,b):b-a\in\Qsq\}$ and $\Om'=\{(a,b):b-a\notin\Qsq\cup\{0\}\}$. Indeed the diagonal is one orbit by translation; given $(a,b),(a',b')\in\Om$, the map $z\mapsto sz+c$ with $s=(b'-a')/(b-a)\in\Qsq$ and $c=a'-sa$ sends $(a,b)$ to $(a',b')$; and likewise on $\Om'$. An invariant kernel is therefore a combination of three indicator functions, and its eigenvalues are the formulas of \cref{lem:spec:affpair}(a) below, through the $c_\xi$ of \cref{lem:spec:gauss}. \begin{lemma}[$\mathrm{Aff}_p$-invariant kernels]\label{lem:spec:affpair} \leavevmode \begin{enumerate}[label=\textup{(\alph*)}] \item Let $\kappa\colon\Fp^2\to\C$ satisfy $\kappa(\gamma a,\gamma b)=\kappa(a,b)$ for $\gamma\in\mathrm{Aff}_p$. Then $\kappa=\alpha\one_{\rm diag}+\beta_+\one_{\Om}+\beta_-\one_{\Om'}$ for constants $\alpha,\beta_\pm$, and the operator $(\mathcal K_\kappa h)(a)=\E_b\kappa(a,b)h(b)$ satisfies $\mathcal K_\kappa e_\xi=\lambda_\xi e_\xi$ with \[ \lambda_0=\frac\alpha p+\frac{p-1}p\cdot\frac{\beta_++\beta_-}2,\qquad \lambda_\xi=\frac1p\Big(\alpha-\frac{\beta_++\beta_-}2\Big)+c_\xi\,\frac{\beta_+-\beta_-}2 \quad(\xi\ne0). \] \item \emph{(Pair laws.)} Let $(u,v)$ be an $\Fp^2$-valued random pair whose law is $\mathrm{Aff}_p$-invariant, $\pi^==\Pr(u=v)$ and $D=\E\chi(v-u)$. The law of $(u,v)$ is $\pi^=\,\Unif(\mathrm{diag})+\pi^+\Unif(\Om)+\pi^-\Unif(\Om')$ with $\pi^++\pi^-=1-\pi^=$ and $\pi^+-\pi^-=D$, and for all $g,h\in L^2_0(\Fp)$ \begin{equation}\label{eq:spec:affpair} \E\big[\overline{g(u)}h(v)\big]=\pi^=\ip gh-\frac{1-\pi^=}{p-1}\ip gh+\frac p{p-1}D\ip g{Ch}. \end{equation} \item \emph{(Covariant fields.)} Let $\nu$ be a probability measure on a finite set $\mathcal Y$ on which $\mathrm{Aff}_p$ acts preserving $\nu$, and let $\mathcal V_1,\dots,\mathcal V_s\colon\mathcal Y\times\Fp\to\C$ satisfy $\mathcal V_k(\gamma y,\gamma a)=\mathcal V_k(y,a)$ for $\gamma\in\mathrm{Aff}_p$. Put $\Gamma_{kl}=\E_\nu\E_a\overline{\mathcal V_k}\mathcal V_l$, $M_{kl}=\E_\nu\overline{\E_a\mathcal V_k}\,\E_a\mathcal V_l$ and $\mathcal P_{kl}=\E_\nu\ip{\mathcal V_k(y,\cdot)}{C\mathcal V_l(y,\cdot)}$. Then for every $\xi\ne0$ and $w\in\C^s$, with $\mathcal V_w=\sum_kw_k\mathcal V_k$, \[ \E_\nu\big|\E_a[\mathcal V_w(y,a)e_\xi(a)]\big|^2 =\frac{w^*\big(\Gamma-M+\chi(\xi)G_\chi\mathcal P\big)w}{p-1}. \] \item \emph{(Commutant and invariant functions, $p\equiv3\pmod4$.)} (i) Every real operator $T$ on $L^2(\Fp)$ that commutes with the operators $h\mapsto h\circ\gamma$, $\gamma\in\mathrm{Aff}_p$, is $\alpha_TI+\beta_T\Jproj+\gamma_TC$ with real $\alpha_T,\beta_T,\gamma_T$. On $L^2_0(\Fp)$ it is $\alpha_TI+\gamma_TC$, a normal operator of norm $(\alpha_T^2+q\gamma_T^2)^{1/2}$, with $\alpha_T=\tr(T)/(p-1)$ and $\gamma_T=\tr(C^*T)/(1-q)$ (traces on $L^2_0(\Fp)$), and it is self-adjoint if and only if $\gamma_T=0$. (ii) Hence, if $\mathrm{Aff}_p$ acts on $(\mathcal Y,\nu)$ as in (c) and $Y,Y'\colon L^2_0(\Fp)\to L^2(\nu)$ map real functions to real functions and intertwine the two actions, then $T=Y^*Y'$ is $\alpha_TI+\gamma_TC$ on $L^2_0(\Fp)$ as in (i), and $Y^*Y=\tr(Y^*Y)/(p-1)\cdot I$. (iii) If the law of a random $x=(x_w)_{w\in W}\in\Fp^W$ is invariant under the simultaneous translations $x\mapsto x+c\one$ and $f$ is a function on $\Fp^W$ with $f(x+c\one)=f(x)$ for all $c$ and $\E f(x)=0$, then $\E[f(x)\mid x_w]=0$ for every $w\in W$. \end{enumerate} \end{lemma} \begin{proof} (a) An invariant $\kappa$ is constant on the three orbits. By translation invariance $\kappa(a,a+d)=\tilde\kappa(d)$ depends only on $d$, so $(\mathcal K_\kappa e_\xi)(a)=e_\xi(a)\E_d\tilde\kappa(d)\ee{\xi d/p}$. For $\xi\ne0$, $\sum_{d\in\Qsq}\ee{\xi d/p}=\frac12\sum_{d\ne0}(1+\chi(d))\ee{\xi d/p}=\frac12(-1+\chi(\xi)G_\chi)$ by \cref{thm:gauss}\ref{it:gauss:quad}, and likewise with $-\chi$ for the non-squares; with $\chi(\xi)G_\chi/p=c_\xi$ this gives $\lambda_\xi$. For $\xi=0$ the sum is $\alpha+\frac{p-1}2(\beta_++\beta_-)$. (b) The law is invariant, so it is constant on the orbits; $\chi(v-u)$ is $0$, $+1$, $-1$ on the diagonal, on $\Om$ and on $\Om'$, which gives the decomposition. The function $\kappa(a,b)=p^2\Pr(u=a,v=b)$ is invariant, with $\alpha=p\pi^=$ and $\beta_\pm=2p\pi^\pm/(p-1)$, since $|\Om|=|\Om'|=p(p-1)/2$. For $g,h\in L^2_0$, $\E[\overline{g(u)}h(v)]=\ip g{\mathcal K_\kappa h}=\sum_{\xi\ne0}\lambda_\xi \overline{\hat g(\xi)}\hat h(\xi)$, and by (a) and \cref{lem:spec:gauss}, $\lambda_\xi=\pi^=-\frac{1-\pi^=}{p-1}+\frac p{p-1}Dc_\xi$. Since $\ip gh=\sum_\xi\overline{\hat g}\hat h$ and $\ip g{Ch}=\sum_\xi c_\xi\overline{\hat g}\hat h$, this is \eqref{eq:spec:affpair}. (c) Put $\kappa(a,b)=\E_\nu[\overline{\mathcal V_w(y,a)}\mathcal V_w(y,b)]$. By the invariance of $\nu$, $\kappa$ is $\mathrm{Aff}_p$-invariant, and the left side is $\E_{a,b}\kappa(a,b)\overline{e_\xi(a)}e_\xi(b)=\ip{e_\xi}{\mathcal K_\kappa e_\xi}=\lambda_\xi$. Now $w^*\Gamma w=\E_a\kappa(a,a)=\alpha$; $w^*Mw=\E_{a,b}\kappa(a,b)=\lambda_0$; and $w^*\mathcal Pw=\E_{a,b}\chi(b-a)\kappa(a,b)=\frac{p-1}{2p}(\beta_+-\beta_-)$. Eliminating $\beta_\pm$ in (a), $\lambda_\xi=(\alpha-\lambda_0+\chi(\xi)G_\chi w^*\mathcal Pw)/(p-1)$. (d) (i) $T=\mathcal K_\kappa$ with $\kappa(a,b)=p\,T(a,b)$, the matrix of $T$ scaled by $p$; $T$ commutes with the square-affine maps exactly when $\kappa$ is invariant, and $\kappa$ is real when $T$ is. By (a), $\kappa=\alpha\one_{\rm diag}+\beta_+\one_{\Om}+\beta_-\one_{\Om'}$ with real coefficients, and since $\one_{\Om}(a,b)=\frac12(1-\one_{a=b}+\chi(b-a))$ and $\one_{\Om'}(a,b)=\frac12(1-\one_{a=b}-\chi(b-a))$, \[ T=\Big(\alpha-\frac{\beta_++\beta_-}2\Big)\frac Ip+\frac{\beta_++\beta_-}2\Jproj +\frac{\beta_+-\beta_-}2\,C . \] On $L^2_0(\Fp)$, $\Jproj=0$, and $C$ has the eigenvalues $c_\xi=\chi(\xi)\eps_Gr\in\{\pm ir\}$, $\xi\ne0$, each value occurring $(p-1)/2$ times (\cref{lem:spec:gauss}). So $\alpha_TI+\gamma_TC$ is normal with the eigenvalues $\alpha_T\pm i\gamma_Tr$, of modulus $(\alpha_T^2+q\gamma_T^2)^{1/2}$; $\tr C=\sum_{\xi\ne0}c_\xi=0$ and $\tr(C^*C)=(p-1)q=1-q$ give the two traces; and $C^*=-C$ shows that $(\alpha_TI+\gamma_TC)^*=\alpha_TI-\gamma_TC$, which equals $\alpha_TI+\gamma_TC$ only if $\gamma_T=0$. (ii) For $\gamma\in\mathrm{Aff}_p$ let $U_\gamma$ and $\tilde U_\gamma$ be the two unitary actions, with $YU_\gamma=\tilde U_\gamma Y$ and $Y'U_\gamma=\tilde U_\gamma Y'$. Then $Y^*\tilde U_\gamma=U_\gamma Y^*$, so $Y^*Y'$ commutes with every $U_\gamma$ and is real; extended by zero on the constants (which the $U_\gamma$ fix) it is an operator as in (i). As $Y^*Y$ is self-adjoint, its coefficient $\gamma_T$ vanishes. (iii) Let $g(t)=\E[f(x)\mid x_w=t]$. The law of $x_w$ is translation invariant, hence uniform, and replacing $x$ by $x+c\one$ gives $g(t)=g(t-c)$ for all $c$; so $g$ is constant, equal to $\E f(x)=0$. \end{proof} By \cref{lem:spec:cutkernel}(d) the laws $\lambda$, $\mu$ and $m_p$ are invariant under $\mathrm{Aff}_p$ and have uniform one-vertex marginals, and so has every pair law obtained from them by taking two coordinates; part (b) applies to all of them. Put \begin{equation}\label{eq:spec:smallconst} \delta^\times_l=\frac{e_{d_l}(p,2n)+e_{d_l+1}(p,2n)}{1-e_{d_l}(p,2n)},\qquad \delta^\mu_l=\frac{e_{d^0_l}(p,n)+e_{d^0_l+1}(p,n)}{1-e_{d^0_l}(p,n)}\qquad(l\in U^+). \end{equation} \begin{lemma}[Small pair constants]\label{lem:spec:small} Assume $e_\Delta(p,2n)<1$. \begin{enumerate}[label=\textup{(\alph*)}] \item For $k,l\in U^+$ with $\varsigma_{kl}=0$ (including $k=l$), $|\E_\lambda\chi(x'_l-x_k)|\le\min(\delta^\times_k,\delta^\times_l)$. If $\varsigma_{kl}\ne0$, then $\E_\lambda\chi(x'_l-x_k)=\chi(\varsigma_{kl})$. In all cases $\E_\lambda\chi(x'_k-x_l)=\chi(-1)\E_\lambda\chi(x'_l-x_k)$. \item For distinct non-adjacent $k,l\in U^+$, $|\E_\mu\chi(x_l-x_k)|\le\min(\delta^\mu_k,\delta^\mu_l)$. If $(k,l)$ is an edge of $G^+$ the value is $1$; if $(l,k)$ is an edge it is $\chi(-1)$. \end{enumerate} \end{lemma} \begin{proof} (a) Let $\varsigma_{kl}=0$ and condition on all labels $y_w$, $w\ne\vartheta l$. By \cref{lem:graphs:vertex}\ref{it:vertex:dens} for $G$ ($2n$ vertices), the label $x'_l=y_{\vartheta l}$ is uniform on its admissible set $\mathcal A$: the values outside the other $2n-1$ labels that satisfy the $d_l$ constraints with the distinct labels of the neighbours of $\vartheta l$. By \cref{lem:extension}\ref{it:ext:coarse}, $|\mathcal A|\in p2^{-d_l}[1-e_{d_l},1+e_{d_l}]$, with $e_t=e_t(p,2n)$. The vertex $k$ is not a neighbour of $\vartheta l$ (this is $\varsigma_{kl}=0$; for $k=l$ it is $\varsigma_{ll}=0$), so $x_k$ is distinct from the roots of these constraints and lies in the excluded set. The subset $\mathcal A^+=\{a\in\mathcal A:a-x_k\in\Qsq\}$ is cut out by $d_l+1$ constraints with distinct roots, so $2|\mathcal A^+|\in p2^{-d_l}[1-e_{d_l+1},1+e_{d_l+1}]$. Since $x'_l\ne x_k$, the conditional expectation of $\chi(x'_l-x_k)$ is $(2|\mathcal A^+|-|\mathcal A|)/|\mathcal A|$, of modulus at most $(e_{d_l}+e_{d_l+1})/(1-e_{d_l})=\delta^\times_l$; average over the conditioning. The swap invariance of $\lambda$ gives $\E\chi(x'_l-x_k)=\E\chi(x_l-x'_k)=\chi(-1)\E\chi(x'_k-x_l)$, the last identity of (a); applying the first bound to the pair $(l,k)$ ($\varsigma_{lk}=-\varsigma_{kl}=0$) gives the bound $\delta^\times_k$. If $\varsigma_{kl}\ne0$, the cross constraint $\varsigma_{kl}(x'_l-x_k)\in\Qsq$ holds $\lambda$-almost surely, so $\chi(x'_l-x_k)=\chi(\varsigma_{kl})$. (b) The same argument for $G^+$ ($n$ vertices, maximum degree $\Delta^+$, $e_{\Delta^+}(p,n)\le e_\Delta(p,2n)<1$), with $d^0_l$ constraints and at most $n-1$ excluded labels. On an edge $(k,l)$, $x_l-x_k\in\Qsq$ almost surely. \end{proof} \subsection{Exact star factorisation in a fixed invariant half law}\label{subsec:spec:actual-stars} The criteria of the following subsections compare a cut kernel with product laws: route~A through the conditional laws of single labels of the opposite half and an explicit model matrix, route~B through explicit normalized stars on allowed sets. When the half law is one fixed law invariant under $\mathrm{Aff}_p$, the stars need no comparison. Every Gram $\mathcal F_\alpha^*\mathcal F_\beta$ of the features defined below is then a combination of $I$ and $C$ (\cref{lem:spec:affpair}(d)), with coefficients given by two traces, and the complete star part of a soft cross kernel (defined in \cref{cor:star-matrix} below) factors exactly through these features. This subsection records the Grams (\cref{lem:general-star}), the star matrix (\cref{cor:star-matrix}), the projections of unobserved features (\cref{lem:hidden-feature}) and the real form of the phase gates (the positive-semidefiniteness tests at the phases $\pm i$; \cref{rem:realified-gates}). Its uses are listed in the opening of this section; it uses neither criterion. \paragraph{Setting.} In this subsection no spectral data are fixed. Let $p\equiv3\pmod4$, $\mathcal H=L^2_0(\Fp)$ and $\Phat=C/r$, the normalized Paley operator of \cref{sec:notation}; by \cref{lem:spec:gauss}, $\Phat e_\xi=\pm ie_\xi$ for $\xi\ne0$, so $\Phat^*=-\Phat$ and $\Phat^2=-I$ on $\mathcal H$. Let $U$ be a finite set and $\mu$ a law on the injective tuples $x=(x_i)_{i\in U}\in\Fp^U$ that is invariant under the diagonal action of $\mathrm{Aff}_p$, for instance the uniform law on the injective strict-square labellings of an oriented graph (\cref{def:graphs:labeling}) or a marginal of such a law. As in the rest of the section, $P_0=I-\Jproj$ is the projection onto the $\mu$-mean-zero functions. For $R\subseteq U$, $z\in\Fp$ and $h\in\mathcal H$ put \begin{gather*} \psi_R(z,x)=\prod_{j\in R}\chi(z-x_j),\qquad w_R(x)=\E_z\psi_R(z,x),\\ (W_Rh)(x)=\E_z\psi_R(z,x)h(z),\qquad (V_ih)(x)=h(x_i), \end{gather*} with $z$ uniform on $\Fp$. The sets $S\subseteq U$ with $|S|\ge2$ are the \emph{supports}, $w_S$ is the \emph{star mean} of $S$, and the maps $V_i$ ($i\in U$) and $W_S/r$ are the \emph{actual features} of $\mu$, the singletons and the stars. We write $\mathcal F_\alpha$, $\alpha\in U\sqcup\mathcal S$, for the features of a set $\mathcal S$ of supports ($\mathcal F_i=V_i$, $\mathcal F_S=W_S/r$), and call $\mathcal F_\alpha^*\mathcal F_\beta$ their \emph{Gram}. \begin{lemma}[Complete actual star synthesis]\label{lem:general-star} In this setting the $V_i$ are isometries of $\mathcal H$ into $L^2_0(\mu)$, the $W_S$ map $\mathcal H$ into $L^2_0(\mu)$, and the ranges of all these maps are orthogonal to the functions of $x$ that are invariant under the simultaneous translations $x\mapsto x+c\one$. \begin{enumerate}[label=\textup{(\alph*)}] \item \emph{(Diagonal Grams.)} On $\mathcal H$, \begin{equation}\label{eq:star-diagonal} W_S^*W_S=\frac{q\big(1-|S|q-\E_\mu w_S^2\big)}{1-q}\,I\preceq qI . \end{equation} \item \emph{(Cross Grams.)} For supports $S,T$ put $\mathcal A_{ST}=\E_\mu\E_z\psi_S\psi_T$, $\mathcal C_{ST}=\E_\mu w_Sw_T$ and $\mathcal B_{ST}=\E_\mu\ip{\psi_S(\cdot,x)}{C\psi_T(\cdot,x)}$. Then, on $\mathcal H$, \begin{equation}\label{eq:star-cross} W_S^*W_T=\frac{q(\mathcal A_{ST}-\mathcal C_{ST})}{1-q}\,I+\frac{\mathcal B_{ST}}{1-q}\,C, \qquad \norm{W_S^*W_T}=\frac q{1-q}\Big((\mathcal A_{ST}-\mathcal C_{ST})^2 +\frac{\mathcal B_{ST}^2}q\Big)^{1/2}. \end{equation} \item \emph{(Pivot bound.)} Let $S\ne T$, $k=|S|$, $l=|T|$, $c=|S\cap T|$, $d=|S\triangle T|$, and $a_1=0$, $a_2=q$, $a_d=(d-1)r$ for $d\ge3$. Let $j\in S\triangle T$ be a \emph{pivot}: given the other coordinates, every value of $x_j$ has conditional probability at most $D_j/p$. Then \begin{equation}\label{eq:star-cross-bound} \frac{\norm{W_S^*W_T}}q\le \frac{\big([a_d+(c+(k-1)(l-1))q]^2+q(D_j-1)\big)^{1/2}}{1-q} . \end{equation} \item \emph{(Singleton entries.)} Let $k=|S|$. Then \begin{equation}\label{eq:singleton-star} \frac{(1-q)\norm{V_i^*W_S}}r\le \begin{cases} \big(r^2(1+(k-1)r)^2+k^2q\big)^{1/2}, & i\notin S,\\ q\sqrt{1+q}, & i\in S,\ k=2,\\ 2\sqrt2\,q, & i\in S,\ k=3,\\ \big((k-1)^2q^2+((k-2)r+q)^2\big)^{1/2}, & i\in S,\ k\ge4, \end{cases} \end{equation} and $\norm{V_i^*V_j}\le r\sqrt{1+q}/(1-q)$ for $i\ne j$. \item \emph{(Disjoint supports and overlapping pair supports.)} If $\rho_S$ bounds the maximal correlation (\cref{def:prelim:maxcorr}) of $x_S$ and $x_{U\setminus S}$, then $\norm{(W_S/r)^*(W_T/r)}\le\rho_S$ for every support $T$ disjoint from $S$. Let $S=\{a,b\}$ and $T=\{a,b'\}$ with $a,b,b'$ distinct, and let $\rho$ bound, for every value of $x_a$, the conditional maximal correlation of $x_b$ and $x_{U\setminus\{a,b\}}$ given $x_a$. Then \begin{equation}\label{eq:pair-overlap} \norm{(W_S/r)^*(W_T/r)}\le\frac{2\rho}{1-q}+\frac{q(q+r)^2}{(1-q)^2} . \end{equation} \item \emph{(Synthesis.)} Let $\mathcal S$ be a set of supports and $\mathcal F\colon\mathcal H^U\oplus\mathcal H^{\mathcal S}\to L^2_0(\mu)$, $\mathcal F\big((h_\alpha)_\alpha\big)=\sum_\alpha\mathcal F_\alpha h_\alpha$, the synthesis of its features. If a symmetric nonnegative matrix $N$ indexed by $U\sqcup\mathcal S$ satisfies $\norm{\mathcal F_\alpha^*\mathcal F_\beta}\le N_{\alpha\beta}$ for $\alpha\ne\beta$, then $\norm{\mathcal F}^2\le1+\lambda_{\max}(N)\le1+\max_\alpha\sum_\beta N_{\alpha\beta}$. \end{enumerate} \end{lemma} \begin{proof} \emph{Equivariance and traces.} The group $\mathrm{Aff}_p$ acts unitarily on $\mathcal H$ by $h\mapsto h\circ\gamma^{-1}$ and, since $\mu$ is invariant, on $L^2(\mu)$ by $F\mapsto F\circ\gamma^{-1}$ (diagonally). For $\gamma(z)=sz+c$ with $s\in\Qsq$, $\chi(\gamma z-\gamma y)=\chi(s)\chi(z-y)=\chi(z-y)$, so $\psi_S(\gamma z,\gamma x)=\psi_S(z,x)$, and $V_i$, $W_S$ intertwine the two actions and map real functions to real functions. Both are of the form $(Yh)(x)=\E_z\phi(z,x)h(z)$ with a real kernel $\phi$: $\phi=\psi_S$ for $W_S$, and $\phi(z,x)=p\one_{z=x_i}$ for $V_i$. By \cref{lem:spec:affpair}(d), the Gram $T=Y^*Y'$ of two such maps is, on $\mathcal H$, $\alpha_TI+\gamma_TC$ with $\alpha_T=\tr(T)/(p-1)$, $\gamma_T=\tr(C^*T)/(1-q)$ and $\norm T=(\alpha_T^2+q\gamma_T^2)^{1/2}$, and $\gamma_T=0$ if $Y=Y'$. If $(e_m)$ is an orthonormal basis of $\mathcal H$, then $(Ye_m)(x)=\ip{\phi(\cdot,x)}{e_m}$, and $\sum_m\overline{\ip f{e_m}}\ip g{e_m}=\ip g{f-\E_zf(z)}$; with $\ip{C^*\phi}{e_m}=\ip\phi{Ce_m}$ this gives, for kernels $\phi$, $\phi'$ of $Y$, $Y'$ and traces on $\mathcal H$, \begin{equation}\label{eq:star-traces} \tr(Y^*Y')=\E_\mu\big(\E_z\phi\phi'-\E_z\phi\,\E_z\phi'\big),\qquad \tr(C^*Y^*Y')=\E_\mu\ip{\phi(\cdot,x)}{C\phi'(\cdot,x)} . \end{equation} \emph{Ranges.} By translation invariance every one-vertex marginal of $\mu$ is uniform, so $V_i$ is an isometry and $\E_\mu V_ih=\E h=0$. Let $F\in L^2(\mu)$ satisfy $F(x+c\one)=F(x)$. By \cref{lem:spec:affpair}(d) applied to $F-\E_\mu F$, $\E_\mu[F\mid x_i]=\E_\mu F$, so $\ip F{V_ih}_\mu=\overline{\E_\mu F}\,\E h=0$. Next $\ip F{W_Sh}_\mu=\E_zh(z)\,\E_\mu[\overline{F(x)}\psi_S(z,x)]$, and the inner expectation does not depend on $z$, since $\psi_S(z+c,x+c\one)=\psi_S(z,x)$ and $\mu$ and $F$ are translation invariant; as $\E h=0$, $\ip F{W_Sh}_\mu=0$. For $F=\one$ this says that $W_Sh$ has $\mu$-mean zero. (a) In \eqref{eq:star-traces} take $\phi=\phi'=\psi_S$. As $x$ is injective, $\psi_S(z,x)^2=1$ except at the $|S|$ labels $x_j$, $j\in S$, so $\tr(W_S^*W_S)=1-|S|q-\E_\mu w_S^2$; divide by $p-1=(1-q)/q$. The bound by $qI$ holds already for $|S|\ge1$, since $\E_\mu w_S^2\ge0$. (b) Take $\phi=\psi_S$, $\phi'=\psi_T$ in \eqref{eq:star-traces}: the traces are $\mathcal A_{ST}-\mathcal C_{ST}$ and $\mathcal B_{ST}$. (c) Since $\chi(z-x_j)^2=1-\one_{z=x_j}$ and the labels are distinct, \[ \psi_S\psi_T=\psi_{S\triangle T}(z,x)-\sum_{j\in S\cap T}\one_{z=x_j}\,\psi_{S\triangle T}(x_j,x), \] so $|\E_z\psi_S\psi_T|\le|\E_z\psi_{S\triangle T}|+cq$. The average of a product of $d$ characters with distinct roots is $0$ for $d=1$, $-q$ for $d=2$ \eqref{eq:two-root}, and at most $(d-1)r$ in modulus for $d\ge3$ (\cref{thm:weil}); so $|\mathcal A_{ST}|\le a_d+cq$. The same facts give $|w_S|\le(k-1)r$ for every support ($w_S=-q$ if $k=2$), so $|\mathcal C_{ST}|\le(k-1)(l-1)q$. For $\mathcal B_{ST}$ let first $j\in S\setminus T$. Conditionally on $x_{U\setminus\{j\}}$ let $\nu_j$ be the law of $x_j$ and $\phi_j(z)=\E[\chi(z-x_j)\mid x_{U\setminus\{j\}}]=\sum_t\nu_j(t)\chi(z-t)$. As $\psi_T$ and $\psi_{S\setminus\{j\}}$ do not depend on $x_j$, $\mathcal B_{ST}=\E_\mu\ip{\phi_j\psi_{S\setminus\{j\}}}{C\psi_T}$. By \eqref{eq:two-root}, $\norm{\phi_j}^2=\sum_{t,t'}\nu_j(t)\nu_j(t')(\one_{t=t'}-q)=\sum_t\nu_j(t)^2-q\le q(D_j-1)$; with $|\psi_{S\setminus\{j\}}|\le1$, $\norm{C\psi_T}\le r$ (\cref{lem:spec:gauss}) and Cauchy--Schwarz, $|\mathcal B_{ST}|\le q(D_j-1)^{1/2}$. If $j\in T\setminus S$, write $\mathcal B_{ST}=\E_\mu\ip{C^*\psi_S}{\psi_T}$ and argue in the same way, as $\norm{C^*}=r$. Insert these bounds in the norm of (b). (d) In \eqref{eq:star-traces} take $\phi=p\one_{z=x_i}$ and $\phi'=\psi_S$: $\tr(V_i^*W_S)=\E_\mu(\psi_S(x_i,x)-w_S)$ and $\tr(C^*V_i^*W_S)=\E_\mu(C\psi_S(\cdot,x))(x_i)=\E_\mu\E_z\chi(z-x_i)\psi_S(z,x)=:\beta_i$. So $(1-q)\norm{V_i^*W_S}/r=\big(q(\E_\mu\psi_S(x_i,x)-\E_\mu w_S)^2+\beta_i^2\big)^{1/2}$. If $i\notin S$, $|\psi_S(x_i,x)|\le1$, $|w_S|\le(k-1)r$, and $\beta_i=\E_\mu w_{S\cup\{i\}}$ has modulus at most $kr$ by \cref{thm:weil}. If $i\in S$, $\psi_S(x_i,x)=0$, and $\chi(z-x_i)\psi_S(z,x)=(1-\one_{z=x_i})\psi_{S\setminus\{i\}}(z,x)$ gives $\beta_i=\E_\mu\big(w_{S\setminus\{i\}}-q\psi_{S\setminus\{i\}}(x_i,x)\big)$: for $k=2$, $w_S=-q$ and $w_{S\setminus\{i\}}=0$, so the trace is $q$ and $|\beta_i|\le q$; for $k=3$, $|w_S|\le2r$ and $w_{S\setminus\{i\}}=-q$, so $|\beta_i|\le2q$; for $k\ge4$, $|w_S|\le(k-1)r$ and $|\beta_i|\le(k-2)r+q$. These give the four cases. For $i\ne j$ take $\phi=p\one_{z=x_i}$, $\phi'=p\one_{z=x_j}$: the traces are $-1$ (injectivity) and $\E_\mu\chi(x_j-x_i)\in[-1,1]$, so $\norm{V_i^*V_j}\le(q^2+q)^{1/2}/(1-q)$. (e) For disjoint $S$, $T$ and $h,h'\in\mathcal H$, $W_Sh$ and $W_Th'$ are functions of $x_S$ and of $x_{U\setminus S}$ with $\mu$-mean zero, of norms at most $r\norm h$ and $r\norm{h'}$ by (a); so $|\ip{W_Sh}{W_Th'}_\mu|\le\rho_Sq\norm h\norm{h'}$, which is the first claim. Now let $S=\{a,b\}$, $T=\{a,b'\}$, and write $(W_Sh)(x)=F_{x_a}(x_b)$ and $(W_Th')(x)=G_{x_a}(x_{b'})$. Fix $x_a=\alpha$. The pair $(x_a,x_b)$ has an invariant law without diagonal mass, so by \cref{lem:spec:affpair}(b) the conditional law of $x_b$ has the density $(1-\one_{\beta=\alpha}+s_{ab}\chi(\beta-\alpha))/(1-q)\le2/(1-q)$ in $\beta$ relative to the uniform law, with $s_{ab}=\E\chi(x_b-x_a)\in[-1,1]$. As $F_\alpha(\beta)=\E_t\chi(t-\beta)\chi(t-\alpha)h(t)=\big(C(\chi(\cdot-\alpha)h)\big)(\beta)$, $\E[|F_\alpha(x_b)|^2\mid x_a=\alpha]\le2r^2\norm h^2/(1-q)$. Summing the density against $F_\alpha$ with \eqref{eq:two-root} and $\chi(-1)=-1$ gives the conditional mean \[ m_F(\alpha)=\E[F_\alpha(x_b)\mid x_a=\alpha] =\frac{q^2h(\alpha)+qs_{ab}(Ch)(\alpha)}{1-q}, \] of norm at most $q(q+r)\norm h/(1-q)$ in $\alpha$; likewise for $G$ and $h'$. Split $F_\alpha=m_F(\alpha)+F^\circ_\alpha$ and $G_\alpha=m_G(\alpha)+G^\circ_\alpha$ into conditional means and fluctuations. The fluctuations are functions of $x_b$ and of $x_{b'}$ with conditional mean zero given $x_a$, so their conditional inner product is at most $\rho\cdot2r^2\norm h\norm{h'}/(1-q)$ in modulus, and the means contribute at most $q^2(q+r)^2\norm h\norm{h'}/(1-q)^2$. Divide the sum by $r^2=q$. (f) The diagonal Grams satisfy $V_i^*V_i=I$ and $(W_S/r)^*(W_S/r)\preceq I$ by (a), so the matrix $I+N$ bounds the norms of all Grams. As $\norm{\mathcal F}^2=\norm{\sum_\alpha\mathcal F_\alpha\mathcal F_\alpha^*}$, \cref{lem:weighted-frame}(a) with unit weights gives the bound by $\lambda_{\max}(I+N)=1+\lambda_{\max}(N)$, and by the largest row sum of $I+N$. \end{proof} \Cref{lem:general-star} is an operator inequality for the whole synthesis: nested and overlapping supports are allowed, and no orthogonality of distinct supports is assumed; the only loss beyond the diagonal Grams is the term $\lambda_{\max}(N)$ in \textup{(f)}. For the uniform law on the injective strict-square labellings of a graph on $n$ vertices, the label $x_j$ is conditionally uniform on its admissible set (\cref{lem:graphs:vertex}\ref{it:vertex:dens}), so \cref{lem:extension}\ref{it:ext:coarse} gives the pivot density $D_j=2^t/(1-e_t(p,n))$, with $t$ the degree of $j$, whenever $e_t(p,n)<1$; the pivot minimizing the right side of \eqref{eq:star-cross-bound} is chosen for each pair of supports. The next statement is the reason for the frame: the star part of a soft cross kernel is a fixed matrix in these features. \begin{corollary}[Complete star matrix]\label{cor:star-matrix} In this setting let $D=(D_{ij})_{i,j\in U}$ be a real matrix with $|D_{ij}|\le1$, and let \[ K_D(x,y)=\prod_{i,j\in U}\big(1+D_{ij}\chi(y_j-x_i)\big) \] be the \emph{soft cross kernel} of $D$ between two copies $x$, $y$ of the half, and write $K_D$ also for the operator on $L^2(\mu)$ with kernel $K_D$ relative to $\mu\otimes\mu$. In the expansion of the product, the \emph{complete star part} is the sum of the terms of the single pairs $(i,j)$, of the \emph{left stars} $\prod_{j\in S}D_{ij}\chi(y_j-x_i)$ with centre $i$ and leaves $S$, and of the \emph{right stars} $\prod_{i\in S}D_{ij}\chi(y_j-x_i)$ with centre $j$ and leaves $S$ ($|S|\ge2$). Let $\mathcal F$ be the synthesis of \cref{lem:general-star}(f) for a set $\mathcal S$ that contains every set of leaves. Then the complete star part, compressed by $P_0$ on both sides, is \[ r\,\mathcal F M(\Phat)\mathcal F^*, \] where $M(\Phat)$ is the block operator matrix indexed by $U\sqcup\mathcal S$ with the singleton block $D\otimes\Phat$, the entries $(-1)^{|S|}\prod_{j\in S}D_{ij}$ (row $i$, column $S$) and $\prod_{i\in S}D_{ij}$ (row $S$, column $j$), each times $I_{\mathcal H}$, and zero block between supports. Let $M(i)$ be the complex matrix obtained by replacing $\Phat$ with the imaginary unit $i$. Then $\norm{r\mathcal FM(\Phat)\mathcal F^*}\le r\norm{\mathcal F}^2\norm{M(i)}$; the same holds for the symmetric and the skew part, with $\operatorname{Sym}M(i)$ and $\operatorname{Skew}M(i)$, and for the difference of two soft kernels in one synthesis, with the difference of their matrices. \end{corollary} \begin{proof} For $f\in L^2(\mu)$ let $g_j=V_j^*f$, so that $\E_\mu[f(y)\mid y_j=t]=\E_\mu f+g_j(t)$, the marginal of $y_j$ being uniform. \emph{Single pairs.} As $\E_t\chi(t-x_i)=0$, $\E_y\chi(y_j-x_i)f(y)=\E_t\chi(t-x_i)g_j(t)=(Cg_j)(x_i)$: the pair $(i,j)$ gives $D_{ij}V_iCV_j^*=rD_{ij}V_i\Phat V_j^*$. \emph{Right stars.} $\E_y\psi_S(y_j,x)f(y)=\E_t\psi_S(t,x)(\E_\mu f+g_j(t))=w_S(x)\E_\mu f+(W_Sg_j)(x)$: the right star gives $\prod_{i\in S}D_{ij}\,(W_SV_j^*+w_S\otimes\one)$. \emph{Left stars.} As $\chi(-1)=-1$, $\prod_{j\in S}\chi(y_j-x_i)=(-1)^{|S|}\psi_S(x_i,y)$. The function $z\mapsto\E_y\psi_S(z,y)f(y)$ has mean $\ip{w_S}f_\mu$ over $z$, and its projection onto $\mathcal H$ is $W_S^*f$; so the left star gives $(-1)^{|S|}\prod_{j\in S}D_{ij}\,(V_iW_S^*+\one\otimes w_S)$. \emph{Centring.} $P_0(\one\otimes w_S)=0$ and $(w_S\otimes\one)P_0=0$, while $V_i$ and $W_S$ map into $L^2_0(\mu)$ and $V_j^*$, $W_S^*$ vanish on the constants (\cref{lem:general-star}). So the compression is the sum of the terms $rD_{ij}V_i\Phat V_j^*$, $(-1)^{|S|}\prod_{j\in S}D_{ij}\,rV_i(W_S/r)^*$ and $\prod_{i\in S}D_{ij}\,r(W_S/r)V_j^*$, which is $r\mathcal FM(\Phat)\mathcal F^*$. \emph{Norms.} By \cref{lem:spec:gauss}, $\mathcal H=\mathcal H_+\oplus\mathcal H_-$ with $\Phat=\pm iI$ on $\mathcal H_\pm$. Write $M(\Phat)=M_0\otimes I+M_1\otimes\Phat$ with real matrices $M_0$, $M_1$. On $\C^{U\sqcup\mathcal S}\otimes\mathcal H_\pm$ it acts as $M(\pm i)\otimes I$, and $M(-i)=\overline{M(i)}$ has the norm of $M(i)$; so $\norm{M(\Phat)}=\norm{M(i)}$, and $\norm{r\mathcal FM(\Phat)\mathcal F^*}\le r\norm{\mathcal F}^2\norm{M(i)}$. Since $\Phat^*=-\Phat$, $M(\Phat)^*$ acts as $M(\pm i)^*\otimes I$ on the same spaces, and the symmetric and skew parts of $\mathcal FM(\Phat)\mathcal F^*$ are $\mathcal F\operatorname{Sym}M(\Phat)\mathcal F^*$ and $\mathcal F\operatorname{Skew}M(\Phat)\mathcal F^*$; the same argument applies to them. For two soft kernels on the same half law both star parts have this form with one synthesis, so their difference is $r\mathcal F\big(M_D(\Phat)-M_{D'}(\Phat)\big)\mathcal F^*$. \end{proof} If $D$ is antisymmetric, as is the matrix $\Delta^E$ of the factors of a cut kernel at $p\equiv3\pmod4$ (\cref{lem:spec:expansion}, \cref{subsec:spec:degone}), then $\prod_{k\in S}D_{kj}=(-1)^{|S|}\prod_{k\in S}D_{jk}$ for every singleton $j$ and support $S$: the block of the right stars is the transpose of the block of the left stars, and $M(i)=\begin{psmallmatrix}iD&A\\A^{\mathsf T}&0\end{psmallmatrix}$, with $A_{jS}=(-1)^{|S|}\prod_{k\in S}D_{jk}$, is Hermitian, of the form tested in \cref{rem:realified-gates}. The star means $w_S$ are not lost: they sit in the rank-one terms $\one\otimes w_S$ and $w_S\otimes\one$, which only the double centring removes. For $|S|\ge3$, $w_S$ is in general a nonconstant translation-invariant function with pointwise bound $|w_S|\le(|S|-1)r$, so it remains in the kernel through these rank-one terms; only the doubly centred matrix omits it. The raw scalar means, the nonstar terms and the coincidences of the kernel are not covered by the corollary and are bounded separately in each application. For two soft kernels on the same half law one synthesis over the union of their supports cancels every common star coefficient exactly. When a cut operator is compressed to the functions of a set $O$ of observed coordinates, as for the merge and constant marginals of the upper range (\cref{prop:observed-caps}), the star matrix splits into its principal part on the features measurable in $x_O$ and the rest. A feature that involves an unobserved coordinate is small after the compression: \begin{lemma}[Unobserved features]\label{lem:hidden-feature} In this setting let $O\subseteq U$, let $\Pi_O$ be the conditional expectation onto the functions of $x_O$, and let $j\in U\setminus O$ be such that, given the other coordinates, every value of $x_j$ has conditional probability at most $D_j/p$. Then \[ \norm{\Pi_OV_j}\le r\Big(\frac{D_j-1}{1-q}\Big)^{1/2},\qquad \norm{\Pi_O(W_S/r)}\le r\Big(\frac{D_j-1}{1-q}\Big)^{1/2}\quad(j\in S). \] No independence of the unobserved coordinates is used. \end{lemma} \begin{proof} Let $\Pi_j$ be the conditional expectation onto the functions of $x_{U\setminus\{j\}}$, and $\nu_j(\cdot\mid x)$ the conditional law of $x_j$ given them. As $O\subseteq U\setminus\{j\}$, $\Pi_O=\Pi_O\Pi_j$ and $\norm{\Pi_O}\le1$, so it suffices to bound $\Pi_jV_j$ and $\Pi_jW_S$. Conditional expectation commutes with the diagonal action of $\mathrm{Aff}_p$, since $\mu$ is invariant; so these maps intertwine the two actions, and their Grams are real self-adjoint operators on $\mathcal H$ commuting with $\mathrm{Aff}_p$, that is, scalars equal to their traces over $p-1=(1-q)/q$ (\cref{lem:spec:affpair}(d)). The map $\Pi_jV_j$ has the kernel $\phi=p\nu_j(z\mid x)$, and by \eqref{eq:star-traces} its Gram has the trace $\E_\mu\big(p\sum_z\nu_j(z\mid x)^2-1\big)\le D_j-1$. The map $\Pi_jW_S$ has the kernel $\phi=\phi_j\psi_{S\setminus\{j\}}$ with $\phi_j(z,x)=\E[\chi(z-x_j)\mid x_{U\setminus\{j\}}]=\sum_t\nu_j(t\mid x)\chi(z-t)$, as $\psi_{S\setminus\{j\}}$ does not depend on $x_j$. By \eqref{eq:star-traces} and $|\psi_{S\setminus\{j\}}|\le1$, its Gram has trace at most $\E_\mu\E_z\phi_j^2$, and as in the proof of \cref{lem:general-star}(c), $\E_z\phi_j^2=\sum_t\nu_j(t\mid x)^2-q\le q(D_j-1)$. Dividing by $p-1$ gives $\norm{\Pi_jV_j}^2\le q(D_j-1)/(1-q)$ and $\norm{\Pi_jW_S}^2\le q^2(D_j-1)/(1-q)$. \end{proof} The division by $\dim\mathcal H=p-1$ is where the invariance enters: a Hilbert--Schmidt bound alone would give only $\norm{\Pi_jW_S}\le r(D_j-1)^{1/2}$. A star with all its leaves observed is measurable in $x_O$ and is not changed by $\Pi_O$; for a star with an unobserved leaf the best unobserved pivot may be chosen. \begin{remark}[Real forms of the phase gates]\label{rem:realified-gates} On $\mathcal H$ the operator $\Phat$ has the eigenvalues $\pm i$, so a coefficient operator built from real matrices and $\Phat$ is the direct sum of its values at $i$ and at $-i$, which are complex conjugate matrices; one test at $\Phat=i$ covers both phases. A Hermitian matrix $X_0+iX_1$ ($X_0$ real symmetric, $X_1$ real antisymmetric) is positive semidefinite if and only if the real symmetric matrix $\begin{psmallmatrix}X_0&-X_1\\X_1&X_0\end{psmallmatrix}$ of twice the size is, since $(u+iv)^*(X_0+iX_1)(u+iv)$ is its quadratic form at $(u,v)$ for real $u,v$; the certificates test this real form by exact rational $LDL^{\mathsf T}$ elimination. A bound $\norm{M(i)}\le k$ for a Hermitian $M(i)=\begin{psmallmatrix}iD&A\\A^*&0\end{psmallmatrix}$, with $D$ real antisymmetric and $A$ real, is $kI\pm M(i)\succeq0$, that is, after eliminating the lower block $kI$, $k^2I-AA^*\pm ikD\succeq0$; a non-Hermitian $M$ uses its singular-value dilation $\begin{psmallmatrix}kI&M\\M^*&kI\end{psmallmatrix}\succeq0$ in the same way. The same real forms serve the matrix test \eqref{eq:spectral-test} at class three (\cref{rem:spectral-criterion:certificate}), the conditional star and joint row gates (\cref{prop:conditional-star,lem:joint-rows}) and the observed caps (\cref{prop:observed-caps}). \end{remark} \subsection{The degree-one part}\label{subsec:spec:degone} Let $\mathcal V_k=\{g(x_k):g\in L^2_0(\Fp)\}\subseteq L^2(\mu)$ and $\mathcal V=\sum_{k\in U^+}\mathcal V_k$, the \emph{degree-one space}, with the $\mu$-orthogonal projection $\Pi_{\mathcal V}$. Since the one-vertex marginals of $\mu$ and of $m_p$ are uniform, every $v\in\mathcal V$ has $\E_\mu v=\E_{m_p}v=0$. For $v=\sum_kg_k(x_k)$ with $g_k\in L^2_0(\Fp)$ put $\hat g(\xi)=(\hat g_k(\xi))_{k\in U^+}\in\C^{U^+}$ and $\norm g^2=\sum_k\norm{g_k}^2=\sum_{\xi\ne0}|\hat g(\xi)|^2$. Then $v=\sum_{\xi\ne0}v_\xi$ with the \emph{mode components} $v_\xi=\sum_k\hat g_k(\xi)e_\xi(x_k)$; if the $g_k$ are real, $\hat g(-\xi)=\overline{\hat g(\xi)}$. The translations $x\mapsto x+c\one$ ($c\in\Fp$) act unitarily on $L^2(\mu)$ and commute with $\Op$, with $\Pi_{\mathcal V}$ and with $\Jproj$ ($\mu$ and $K$ are translation invariant, and $\mathcal V$ is a translation-invariant subspace). Hence $L^2(\mu)$ is the orthogonal sum of the \emph{isotypic subspaces} $\mathcal W_\xi=\{F:F(x+c\one)=e_\xi(c)F(x)\ \text{for all}\ c\}$, $\xi\in\Fp$; each is preserved by $\Op$, $\Pi_{\mathcal V}$ and $P_0$, and $v_\xi\in\mathcal W_\xi$. Let $\Delta^E$ be the $U^+\times U^+$ matrix with $\Delta^E_{kl}=\chi(\varsigma_{kl})$ if $\varsigma_{kl}\ne0$ and $0$ otherwise. It depends on $p$ only through $\chi(-1)$: it is the $0/1$ matrix of the cross pairs (symmetric) if $p\equiv1\pmod4$, and the antisymmetric matrix $(\varsigma_{kl})$ if $p\equiv3\pmod4$. Let $\Lambda_D\ge\norm{\Delta^E}$ be a certified bound (the certificates use an exact rational one). Put \begin{gather} \Azero(\xi)=\chi(\xi)\eps_G\,\Delta^E,\qquad \eta_Q=\frac{\Lambda_D}{p-1}+\frac p{p-1}\max_k\sum_{l:\,\varsigma_{kl}=0}\min(\delta^\times_k,\delta^\times_l) +\frac n{(p-1)r},\label{eq:spec:Azero}\\ \eps_V=\frac{n-1}{p-1}+\frac p{p-1}\,r\,\max_k\Big(d^0_k+\sum_{l\ne k,\,l\not\sim k} \min(\delta^\mu_k,\delta^\mu_l)\Big).\label{eq:spec:epsV} \end{gather} $\Azero(\xi)$ is Hermitian: for $p\equiv1\pmod4$, $\eps_G$ is real and $\Delta^E$ real symmetric; for $p\equiv3\pmod4$, $\eps_G$ is imaginary and $\Delta^E$ real antisymmetric. Also $\Azero(\xi)^*\Azero(\xi)=(\Delta^E)^{\mathsf T}\Delta^E$. \begin{lemma}[The degree-one block]\label{lem:spec:degone} Assume $e_\Delta(p,2n)<1$. \begin{enumerate}[label=\textup{(\alph*)}] \item For $v=\sum_kg_k(x_k)$ and $v'=\sum_kh_k(x_k)$ in $\mathcal V$ (complex coefficients allowed), $\E_\lambda[\overline{v(x)}v'(x')]=\ip v{\Op v'}_\mu=\sum_{\xi\ne0}\hat g(\xi)^*\mathbf Q(\xi)\hat h(\xi)$, where $\mathbf Q(\xi)_{kl}=-\frac1{p-1}+\frac p{p-1}c_\xi\delta^\times_{kl}$ and $\delta^\times_{kl}=\E_\lambda\chi(x'_l-x_k)$. The matrix $\mathbf Q(\xi)$ is Hermitian and $\mathbf Q(-\xi)=\overline{\mathbf Q(\xi)}$. \item $\mathbf Q(\xi)/r=\Azero(\xi)+E_Q(\xi)$ with $E_Q(\xi)$ Hermitian, $\norm{E_Q(\xi)}\le\eta_Q$, and $\norm{\Azero(\xi)}=\norm{\Delta^E}$. \item For $\xi\ne0$ and $w\in\C^{U^+}$, $\norm{\sum_kw_ke_\xi(x_k)}^2_\mu=w^*\mathbf N(\xi)w$ with $\mathbf N(\xi)=I-\frac{\one\one^{\mathsf T}-I}{p-1}+\frac p{p-1}c_\xi\Delta^\mu$, where $\Delta^\mu_{kl}=\E_\mu\chi(x_l-x_k)$ ($k\ne l$) and $\Delta^\mu_{kk}=0$; and $\norm{\mathbf N(\xi)-I}\le\eps_V$. Different mode components are orthogonal in $L^2(\mu)$. Hence $(1-\eps_V)\norm g^2\le\norm v^2_\mu\le(1+\eps_V)\norm g^2$ for every $v\in\mathcal V$. \end{enumerate} \end{lemma} \begin{proof} (a) The identity $\E_\lambda[\overline{v(x)}v'(x')]=\ip v{\Op v'}_\mu$ is \cref{lem:spec:cutkernel}(b), extended to complex functions by linearity. The pair $(x_k,x'_l)$ has an $\mathrm{Aff}_p$-invariant law with $\pi^==0$ (injectivity across the cut) and $D=\delta^\times_{kl}$, so by \cref{lem:spec:affpair}(b) $\E_\lambda[\overline{g_k(x_k)}h_l(x'_l)]=-\frac1{p-1}\ip{g_k}{h_l}+\frac p{p-1}\delta^\times_{kl} \ip{g_k}{Ch_l}$. By Parseval and \cref{lem:spec:gauss}, $\ip{g_k}{h_l}=\sum_\xi\overline{\hat g_k(\xi)}\hat h_l(\xi)$ and $\ip{g_k}{Ch_l}=\sum_\xi c_\xi\overline{\hat g_k(\xi)}\hat h_l(\xi)$, and the term $\xi=0$ vanishes. Here $\delta^\times_{kl}$ is real and $\delta^\times_{lk}=\chi(-1)\delta^\times_{kl}$ (\cref{lem:spec:small}(a)); with $\overline{c_\xi}=\chi(-1)c_\xi$ this gives $\overline{\mathbf Q(\xi)_{lk}}=\mathbf Q(\xi)_{kl}$, and $\overline{c_\xi}=c_{-\xi}$ gives $\mathbf Q(-\xi)=\overline{\mathbf Q(\xi)}$. (b) Write $\delta^\times=\Delta^E+\Delta^{\rm sm}$, where $\Delta^{\rm sm}_{kl}=\delta^\times_{kl}$ if $\varsigma_{kl}=0$ and $0$ otherwise (\cref{lem:spec:small}(a)). With $c_\xi/r=\chi(\xi)\eps_G$ and $\frac p{p-1}=1+\frac1{p-1}$, \[ \mathbf Q(\xi)/r=\Azero(\xi)+\frac{\Azero(\xi)}{p-1}+\frac p{p-1}\chi(\xi)\eps_G\Delta^{\rm sm} -\frac{\one\one^{\mathsf T}}{(p-1)r}. \] $|\chi(\xi)\eps_G|=1$, so $\norm{\Azero(\xi)}=\norm{\Delta^E}\le\Lambda_D$. The matrix of moduli $|\Delta^{\rm sm}|$ is symmetric with entries at most $\min(\delta^\times_k,\delta^\times_l)$; by the Schur test its norm, and hence $\norm{\Delta^{\rm sm}}$, is at most the maximal row sum in \eqref{eq:spec:Azero}. $\norm{\one\one^{\mathsf T}}=n$. This gives $\norm{E_Q}\le\eta_Q$, and $E_Q$ is Hermitian as a difference of Hermitian matrices. (c) For $k\ne l$, \cref{lem:spec:affpair}(b) for $(x_k,x_l)$ under $\mu$ ($\pi^==0$, $D=\Delta^\mu_{kl}$) gives $\E_\mu[\overline{e_\xi(x_k)}e_\xi(x_l)]=-\frac1{p-1}+\frac p{p-1}c_\xi\Delta^\mu_{kl}$, and the diagonal terms are $1$; this is the formula for $\mathbf N(\xi)$. As in (a), $c_\xi\Delta^\mu$ is Hermitian. Its norm is at most $r$ times the maximal row sum of the symmetric matrix $|\Delta^\mu|$, whose entries are $1$ on the $d^0_k$ internal edges at $k$ and at most $\min(\delta^\mu_k,\delta^\mu_l)$ otherwise (\cref{lem:spec:small}(b)); and $\norm{\one\one^{\mathsf T}-I}=n-1$. So $\norm{\mathbf N(\xi)-I}\le\eps_V$. The mode components $v_\xi$ lie in the mutually orthogonal spaces $\mathcal W_\xi$, and $\norm g^2=\sum_\xi|\hat g(\xi)|^2$. \end{proof} \subsection{Coupling degree-one functions to the remainder}\label{subsec:spec:coupling} The spectral criteria split test functions into the degree-one space $\mathcal V$, handled by Fourier analysis in the preceding subsection, and its orthogonal complement. What remains is the leakage from $\mathcal V$ into the complement under the cut operator, namely $\norm{(I-\Pi_{\mathcal V})\Op F_V}$ for $F_V\in\mathcal V$; this subsection bounds it. Write $\Op=\varrho\cdot\mathcal P$, i.e.\ $(\Op H)(x)=\varrho(x)(\mathcal PH)(x)$, with $(\mathcal PH)(x)=\E_\lambda[H(x')\mid x]$. Then $\Op F_V$ is controlled by the conditional laws of the single opposite labels $x'_k$ given $x$. These are probability vectors on explicit allowed sets with almost constant densities, and the model matrix $\Hmat$ below is the Gram matrix that their densities would have if they were exactly the normalized indicators of the allowed sets. Since route~B (\cref{subsec:spec:routeB}) needs the same estimates for the uniform laws on the allowed sets, we state them for a family of such densities. For $x\in\mathcal I^+$ and $k\in U^+$ the \emph{allowed set} is \[ \Phi_k(x)=\{a\in\Fp\setminus x(U^+):\ \varsigma_{jk}(a-x_j)\in\Qsq\ \text{for all}\ j\in N(k)\}. \] It is a set as in \cref{lem:extension} with the $r_k$ distinct roots $x_j$, $j\in N(k)$, and the excluded set $x(U^+)$ of $n$ labels, so $|\Phi_k(x)|\in p2^{-r_k}[1-\hat e_k,1+\hat e_k]$ with $\hat e_k=e_{r_k}(p,n)$ (\cref{lem:extension}\ref{it:ext:coarse}). For $\gamma\in\mathrm{Aff}_p$, $\Phi_k(\gamma x)=\gamma\Phi_k(x)$. \begin{definition}[Coupling data]\label{def:coupling-data} \emph{Coupling data} at $p$ consist of a law $\nu$ on $\mathcal I^+$ and, for every $k\in U^+$ and $x\in\mathcal I^+$, a probability vector $P_k(\cdot\mid x)$ on $\Fp$ supported on $\Phi_k(x)$, such that: \begin{enumerate}[label=\textup{(\roman*)}] \item $\nu$ is $\mathrm{Aff}_p$-invariant, and its density with respect to $\mu$ takes values in an interval $[c,R_\nu c]$ with $c>0$ and $R_\nu\ge1$; \item $P_k(\gamma a\mid\gamma x)=P_k(a\mid x)$ for $\gamma\in\mathrm{Aff}_p$; \item $P_k(a\mid x)=(1+\delta_k(a;x))/|\Phi_k(x)|$ on $\Phi_k(x)$, with $1+\delta_k\in[1/R'_k,R'_k]$ for numbers $R'_k\ge1$; we put $\delta_k=0$ off $\Phi_k(x)$ and $\delta'_k=R'_k-1$, so $|\delta_k|\le\delta'_k$. \end{enumerate} Put $\Psi_k(x,a)=pP_k(a\mid x)-1$, a function with $\E_a\Psi_k(x,a)=0$ for $a$ uniform on $\Fp$, and \[ \widetilde\Hmat_{kl}=\E_\nu\ip{\Psi_k(x,\cdot)}{\Psi_l(x,\cdot)},\qquad \mathbf D_{kl}=\E_\nu\ip{\Psi_k(x,\cdot)}{C\Psi_l(x,\cdot)},\qquad \mathbf M(\xi)=\frac{\widetilde\Hmat}{p-1}+\frac p{p-1}c_\xi\mathbf D . \] For $F_V=\sum_kg_k(x_k)\in\mathcal V$ let $(\mathcal PF_V)(x)=\sum_k\sum_aP_k(a\mid x)g_k(a)$. \end{definition} The two instances used below are these. \begin{enumerate}[label=\textup{(\Alph*)}] \item \emph{The cut.} $\nu=m_p$, and $P_k(\cdot\mid x)$ is the conditional law of $x'_k$ given $x$ under $\lambda$; then $\mathcal PF_V(x)=\E_\lambda[F_V(x')\mid x]$. Here $R_\nu=\Rcut$: by \cref{lem:spec:cutkernel}(b),(c) and its proof, $\varrho=N/\E_\mu N$ with $N_-\le N\le N_+$ and $N_+/N_-=\Rcut$. Condition (ii) holds because $\lambda$ is $\mathrm{Aff}_p$-invariant. For (iii), let $\mathfrak o_k$ be the order of $U^+$ that starts with $k$ and then lists $U^+\setminus\{k\}$ in the reverse of the deletion order $\mathfrak o$; for $i\ne k$ let $t'_{k,i}$ be $r_i$ plus the number of $G^+$-neighbours of $i$ preceding $i$ in $\mathfrak o_k$, and \begin{equation}\label{eq:spec:Rprime} R'_k=\prod_{i\ne k}\frac{1+e_{t'_{k,i}}(p,2n)}{1-e_{t'_{k,i}}(p,2n)} . \end{equation} Let $N_k(a)$ be the number of $x'\in\mathcal I^+$ with $K(x,x')=1$ and $x'_k=a$, so that $P_k(a\mid x)=N_k(a)/\sum_bN_k(b)$. If $a\notin\Phi_k(x)$ then $N_k(a)=0$ (injectivity across the cut, or a cross constraint at $k$ fails). If $a\in\Phi_k(x)$, label the vertices $i\ne k$ of $x'$ in the order $\mathfrak o_k$: when $x'_i$ is chosen, its constraints are the $r_i$ cross constraints with the roots $x_j$, $j\in N(i)$, and the internal constraints with its already labelled $x'$-neighbours (including $k$), $t'_{k,i}\le d_i\le \Delta$ constraints in all; their roots are distinct, and the excluded set $x(U^+)\cup\{\text{labels already chosen}\}$ has fewer than $2n$ elements and contains them. By \cref{lem:extension}\ref{it:ext:coarse} the number of choices lies in $p2^{-t'_{k,i}}[1-e_{t'_{k,i}}(p,2n),1+e_{t'_{k,i}}(p,2n)]$, whatever the earlier choices. Hence $N_k(a)\in[L_k,U_k]$ on $\Phi_k(x)$, with $L_k>0$ and $U_k/L_k=R'_k$, and $1+\delta_k(a)=N_k(a)/\operatorname{avg}_{\Phi_k}N_k\in[1/R'_k,R'_k]$, where $\operatorname{avg}_{\Phi_k}N_k:= |\Phi_k(x)|^{-1}\sum_{a\in\Phi_k(x)}N_k(a)$. \item \emph{Explicit stars.} $\nu=\mu$, and $P_k(\cdot\mid x)$ is the uniform law on $\Phi_k(x)$: $R_\nu=1$ and $R'_k=1$, $\delta_k=0$. \end{enumerate} \begin{lemma}[Modes of coupling data]\label{lem:coupling-modes} For coupling data and $F_V=\sum_kg_k(x_k)\in\mathcal V$, $\norm{\mathcal PF_V}^2_\nu=\sum_{\xi\ne0}\hat g(\xi)^*\mathbf M(\xi)\hat g(\xi)$, and $\mathbf M(\xi)$ is Hermitian. In instance \textup{(A)}, $\norm{\Op F_V}^2_\mu\le(\sup\varrho)\,\norm{\mathcal PF_V}^2_{m_p}$. \end{lemma} \begin{proof} Since $\E_a[pP_k(a\mid x)]=1$ and $\E_ag_k=0$, $\sum_aP_k(a\mid x)g_k(a)=\E_a[\Psi_k(x,a)g_k(a)]$. Hence $\mathcal PF_V=\sum_{\xi\ne0}Y_\xi$ with $Y_\xi(x)=\E_a[\sum_k\hat g_k(\xi)\Psi_k(x,a)e_\xi(a)]$. By (ii) for the translations, $Y_\xi(x+c\one)=e_\xi(c)Y_\xi(x)$, and $\nu$ is translation invariant; so the $Y_\xi$ are orthogonal in $L^2(\nu)$. By \cref{lem:spec:affpair}(c) with $\mathcal Y=\mathcal I^+$ and the covariant fields $\Psi_k$, for which $M=0$, $\norm{Y_\xi}^2_\nu=\hat g^*(\widetilde\Hmat+\chi(\xi)G_\chi\mathbf D)\hat g/(p-1)=\hat g^*\mathbf M(\xi)\hat g$, because $\chi(\xi)G_\chi=pc_\xi$. $\mathbf M(\xi)$ is Hermitian, since the left side is real for every $\hat g$. In instance (A), $\Op H=\varrho\cdot\mathcal PH$ (\cref{lem:spec:cutkernel}(b)), so $\norm{\Op F_V}^2_\mu=\E_\mu[\varrho^2|\mathcal PF_V|^2]=\E_{m_p}[\varrho|\mathcal PF_V|^2]$. \end{proof} \paragraph{The model.} For $J\subseteq U^+$ let $\eps_J\in\R^{U^+}$ have the entries $(\eps_J)_k=\prod_{j\in J}\chi(\varsigma_{jk})$ if $J\subseteq N(k)$ and $0$ otherwise, and write $\eps_J\cdot w=\sum_k(\eps_J)_kw_k$. The \emph{star Gram model} is \begin{equation}\label{eq:spec:H} \Hmat=\sum_{\emptyset\ne J\subseteq U^+}\eps_J\eps_J^{\mathsf T},\qquad \Hmat_{kl}=\prod_{j\in N(k)\cap N(l)}\big(1+\chi(\varsigma_{jk}\varsigma_{jl})\big)-1 . \end{equation} Thus $\Hmat\succeq0$, $\Hmat_{kk}=2^{r_k}-1$, and $\norm\Hmat_{\rm row}=\max_k\sum_l|\Hmat_{kl}|\ge\norm\Hmat$. Distinct $k,l$ are \emph{inconsistent} if $\chi(\varsigma_{jk}\varsigma_{jl})=-1$ for some $j\in N(k)\cap N(l)$ (then $\Hmat_{kl}=-1$), and \emph{consistent} otherwise. \begin{definition}[The coupling model]\label{def:coupling-model} A set $J\subseteq U^+$ with $|J|\ge2$ is \emph{coverable} if $G^+[J]$ has no isolated vertex. Put \[ \Hmat^{\rm cov}=\sum_{\substack{|J|\ge2\\ J\ \text{coverable}}}\eps_J\eps_J^{\mathsf T},\qquad \Hmat^{\rm nc}=\sum_{\substack{|J|\ge2\\ J\ \text{not coverable}}}\eps_J\eps_J^{\mathsf T},\qquad \Hmat^+=\Hmat+\one_{p\equiv1(4)}\Hmat^{\rm cov}. \] These matrices, $\Delta^E$ and $\Hmat$ depend on $p$ only through its class $\mathfrak c$; we write $\Hmat_{(\mathfrak c)}$, $\Hmat^+_{(\mathfrak c)}$, $\Delta^E_{(\mathfrak c)}$ when the class matters, and put \[ \mathbf A_{1,\pm}=\pm\Delta^E_{(1)},\qquad \mathbf A_{3,\pm}=\pm i\,\Delta^E_{(3)}. \] By \cref{lem:spec:gauss}, for every $\xi\ne0$ the matrix $\Azero(\xi)$ is one of $\mathbf A_{\mathfrak c,+}$, $\mathbf A_{\mathfrak c,-}$, both values occur, and $\mathbf A_{\mathfrak c,\pm}^*\mathbf A_{\mathfrak c,\pm}=(\Delta^E_{(\mathfrak c)})^{\mathsf T}\Delta^E_{(\mathfrak c)}$. For a real symmetric matrix $X$, $\bar\lambda(X)$ denotes a fixed certified number with $\bar\lambda(X)\ge\lambda_{\max}(X)$; every formula below uses this fixed number (an exact $LDL^{\mathsf T}$ certificate of $\bar\lambda I-X\succeq0$, or the maximal absolute row sum). \end{definition} $\Hmat^{\rm cov}$ and $\Hmat^{\rm nc}$ are Gram sums, hence positive semidefinite. For $p\equiv1\pmod4$, $\chi(-1)=1$, so $(\eps_J)_k=[J\subseteq N(k)]$, $\Delta^E_{kl}=[\varsigma_{kl}\ne0]$, $\Hmat_{kl}=2^{|N(k)\cap N(l)|}-1$, and every pair is consistent. \paragraph{The Gram comparison.} Put $\beta_{kk}=2^{r_k}\hat e_k/(1-\hat e_k)$, and for consistent $k\ne l$, with $u_{kl}=|N(k)\cup N(l)|$ and $e_u=e_{u_{kl}}(p,n)$, \begin{equation}\label{eq:spec:beta} \beta_{kl}=2^{|N(k)\cap N(l)|}\max\Big(\frac{1+e_u}{(1-\hat e_k)(1-\hat e_l)}-1,\ 1-\frac{1-e_u}{(1+\hat e_k)(1+\hat e_l)}\Big); \end{equation} $\beta_{kl}=0$ for inconsistent $k\ne l$, and $\eps'_H=\max_k\sum_l\beta_{kl}$. For consistent $k\ne l$ put $\Upsilon_{kl}=2^{|N(k)\cap N(l)|}(1+e_u)/((1-\hat e_k)(1-\hat e_l))$, and $\Upsilon_{kl}=0$ otherwise (in particular for inconsistent $k\ne l$; the diagonal values $\Upsilon_{kk}$ are not used). For coupling data put \[ \eps_X=\max_k\Big[\frac{2^{r_k}\delta'^2_k}{1-\hat e_k}+\sum_{l\ne k}\Upsilon_{kl} \big(\delta'_k+\delta'_l+\delta'_k\delta'_l\big)\Big]. \] \begin{lemma}[Gram comparison]\label{lem:spec2:gram} Assume $e_\Delta(p,2n)<1$ and let coupling data be given. Let $\psi_k(x,\cdot)=(p/|\Phi_k(x)|)\one_{\Phi_k(x)}-1$ and $\Hmat^0_{kl}=\E_\nu\ip{\psi_k}{\psi_l}$. Then $\Hmat^0\preceq\Hmat+\eps'_HI$ and $\widetilde\Hmat\preceq\Hmat+\eps_HI$ with $\eps_H:=\eps'_H+\eps_X$. In instance \textup{(B)}, $\widetilde\Hmat=\Hmat^0$ and $\eps_X=0$. \end{lemma} \begin{proof} \emph{The model.} Fix $x$. Then $\ip{\psi_k}{\psi_l}=p|\Phi_k\cap\Phi_l|/(|\Phi_k||\Phi_l|)-1$. For $k=l$ this is $p/|\Phi_k|-1$, while $\Hmat_{kk}+1=2^{r_k}$ and $p/|\Phi_k|\in2^{r_k}[(1+\hat e_k)^{-1},(1-\hat e_k)^{-1}]$; so the two differ by at most $\beta_{kk}$. For inconsistent $k\ne l$ some $j\in N(k)\cap N(l)$ requires $a-x_j\in\varsigma_{jk}\Qsq$ and $a-x_j\in\varsigma_{jl}\Qsq$, which are disjoint sets; so $\Phi_k\cap\Phi_l=\emptyset$ and both entries are $-1$. For consistent $k\ne l$ the two constraints at a common $j$ coincide, so $\Phi_k\cap\Phi_l$ is cut out by $u_{kl}$ constraints with distinct roots and has $p2^{-u_{kl}}[1-e_u,1+e_u]$ elements; since $2^{r_k+r_l-u_{kl}}=2^{|N(k)\cap N(l)|}=\Hmat_{kl}+1$, the entries differ by at most $\beta_{kl}$. These bounds hold for every $x$; average over $\nu$ and apply Gershgorin to the real symmetric matrix $\Hmat^0-\Hmat$. \emph{The deviations.} By (iii), $pP_k=(1+\psi_k)(1+\delta_k)$, so $\Psi_k=\psi_k+(1+\psi_k)\delta_k$ and $\widetilde\Hmat=\Hmat^0+X+X^{\mathsf T}+Y$ with $X_{kl}=\E_\nu\ip{\psi_k}{(1+\psi_l)\delta_l}$ and $Y_{kl}=\E_\nu\ip{(1+\psi_k)\delta_k}{(1+\psi_l)\delta_l}$. Since $P_l$ is a probability on $\Phi_l$, $\sum_{a\in\Phi_l}\delta_l(a)=0$, and therefore \[ \ip{\psi_k}{(1+\psi_l)\delta_l}=\frac{p^2}{|\Phi_k||\Phi_l|}\E_a[\one_{\Phi_k\cap\Phi_l}\delta_l] -\frac p{|\Phi_l|}\E_a[\one_{\Phi_l}\delta_l] =\frac{p^2}{|\Phi_k||\Phi_l|}\E_a[\one_{\Phi_k\cap\Phi_l}\delta_l]. \] For $k=l$ this vanishes, so $X_{kk}=0$. For inconsistent $k\ne l$, $X_{kl}=Y_{kl}=0$. For consistent $k\ne l$, $p|\Phi_k\cap\Phi_l|/(|\Phi_k||\Phi_l|)\le\Upsilon_{kl}$, so $|X_{kl}|\le\Upsilon_{kl}\delta'_l$ and $|Y_{kl}|\le\Upsilon_{kl}\delta'_k\delta'_l$. Finally $Y_{kk}\le\E_\nu(p/|\Phi_k|)\delta'^2_k\le2^{r_k}\delta'^2_k/(1-\hat e_k)$. The matrix of these bounds for $|X_{kl}|+|X_{lk}|+|Y_{kl}|$ is symmetric, so by Gershgorin $X+X^{\mathsf T}+Y\preceq\eps_XI$. In instance (B), $\delta_k=0$. \end{proof} \paragraph{The Paley part.} For $k\in U^+$, $J\subseteq N(k)$, $a\in\Fp$ and $x\in\mathcal I^+$ put \[ \chi_{J,k}(a;x)=\prod_{j\in J}\chi(\varsigma_{jk}(a-x_j)),\qquad \varphi_k(a;x)=\prod_{j\in N(k)}\big(1+\chi(\varsigma_{jk}(a-x_j))\big) =\sum_{J\subseteq N(k)}\chi_{J,k}(a;x), \] $\varphi^\circ_k=\varphi_k-1$ and, for coupling data, $E_k=pP_k(\cdot\mid x)-\varphi_k$, so that $\Psi_k=\varphi^\circ_k+E_k$. For $J\subseteq U^+$ let $g_J(a;x)=\prod_{j\in J}\chi(a-x_j)$, so that $\chi_{J,k}=(\eps_J)_kg_J$, and \[ S_J(x_J)=\ip{g_J}{Cg_J}=\E_{a,b}\,g_J(a)\chi(b-a)g_J(b),\qquad t_J=\E_\nu S_J(x_J). \] Put \begin{gather*} \theta_j=\Big(\frac{R_\nu2^{d^0_j}}{1-e_{d^0_j}(p,n)}-1\Big)^{1/2},\qquad \theta_{\max}=\max_j\theta_j,\\ \rho_{\rm row}=\max_k(2^{r_k}-1)\sum_l(2^{r_l}-1),\qquad \eps_{\ne}=r\,\theta_{\max}\rho_{\rm row},\\ \Delta_k=\max\Big(\frac{R'_k}{1-\hat e_k}-1,\ 1-\frac1{(1+\hat e_k)R'_k}\Big),\qquad \hat E^2=\sum_k\Big(2^{r_k}(1+\hat e_k)\Delta_k^2+\frac{n4^{r_k}}p\Big), \end{gather*} and, for numbers $\Gamma_E\ge0$ and $\eps_H$ with $\widetilde\Hmat\preceq\Hmat+\eps_HI$, \begin{equation}\label{eq:spec:rem} \eps_{\rm rem}(\Gamma_E)=2\big(\Gamma_E(\bar\lambda(\Hmat)+\eps_H)\big)^{1/2}+\Gamma_E . \end{equation} The notation $\eps_{\rm rem}(\Gamma_E)$ suppresses the dependence on $\eps_H$. \begin{lemma}[The Paley part]\label{lem:spec2:paley} Assume $e_\Delta(p,2n)<1$ and let coupling data be given. \begin{enumerate}[label=\textup{(\alph*)}] \item For every $x\in\mathcal I^+$ and $w\in\C^{U^+}$, $\norm{\sum_kw_kE_k(\cdot;x)}\le\hat E|w|$. \item Let $\Gamma_E$ satisfy $\E_\nu\norm{\sum_kw_kE_k(\cdot;x)}^2\le\Gamma_E|w|^2$ for all $w$ (by (a), $\Gamma_E=\hat E^2$ is admissible), and $\eps_H$ as above. Then for $w\in\C^{U^+}$ \[ \Big|w^*\mathbf Dw-\sum_{|J|\ge2}t_J\,|\eps_J\cdot w|^2\Big|\le r\big(\eps_{\ne}+\eps_{\rm rem}(\Gamma_E)\big)|w|^2 . \] \item $S_J=0$ if $|J|=1$, $|S_J|\le r$ for every $J$, and $S_J=0$ (so $t_J=0$) for every $J$ if $p\equiv3\pmod4$. \end{enumerate} \end{lemma} \begin{proof} (a) Let $\lambda_k=p2^{-r_k}/|\Phi_k|\in[(1+\hat e_k)^{-1},(1-\hat e_k)^{-1}]$. For $a\notin x(U^+)$ every factor of $\varphi_k$ is $0$ or $2$, so $\varphi_k(a;x)=2^{r_k}\one_{\Phi_k}(a)$; for $a\in x(U^+)$, $0\le\varphi_k\le2^{r_k}$ and $P_k(a\mid x)=0$. On $\Phi_k$, $E_k=2^{r_k}(\lambda_k(1+\delta_k)-1)$ with $\lambda_k(1+\delta_k)\in[1/((1+\hat e_k)R'_k),R'_k/(1-\hat e_k)]$, so $|E_k|\le2^{r_k}\Delta_k$ there; $E_k=0$ off $\Phi_k\cup x(U^+)$, and $|E_k|\le2^{r_k}$ on the $n$ points of $x(U^+)$. Since $|\Phi_k|/p\le2^{-r_k}(1+\hat e_k)$, $\norm{E_k}^2\le2^{r_k}(1+\hat e_k)\Delta_k^2+n4^{r_k}/p$, and Cauchy--Schwarz gives $\norm{\sum_kw_kE_k}\le\hat E|w|$. (b) \emph{Splitting.} With $\Psi_w=\sum_kw_k\Psi_k$, $\varphi^\circ_w=\sum_kw_k\varphi^\circ_k$ and $E_w=\sum_kw_kE_k$, \[ w^*\mathbf Dw=\E_\nu\ip{\Psi_w}{C\Psi_w}=\E_\nu\ip{\varphi^\circ_w}{C\varphi^\circ_w} +\E_\nu\ip{\varphi^\circ_w}{CE_w}+\E_\nu\ip{E_w}{C\Psi_w}. \] As $\norm{\varphi^\circ_w}\le\norm{\Psi_w}+\norm{E_w}$ and $\norm C=r$, the last two terms are at most $r\E_\nu[\norm{E_w}(2\norm{\Psi_w}+\norm{E_w})]$, which by Cauchy--Schwarz in $x$ is at most $r\big(2\Gamma_E^{1/2}|w|(\E_\nu\norm{\Psi_w}^2)^{1/2}+\Gamma_E|w|^2\big)$; and $\E_\nu\norm{\Psi_w}^2=w^*\widetilde\Hmat w\le(\bar\lambda(\Hmat)+\eps_H)|w|^2$. This is $r\eps_{\rm rem}(\Gamma_E)|w|^2$. The main term is \[ \E_\nu\ip{\varphi^\circ_w}{C\varphi^\circ_w}=\sum_{k,l}\overline{w_k}w_l \sum_{\emptyset\ne J\subseteq N(k)}\ \sum_{\emptyset\ne J'\subseteq N(l)} \E_\nu\ip{\chi_{J,k}}{C\chi_{J',l}} . \] \emph{Terms with $J\ne J'$.} Suppose $j\in J\setminus J'$ (if $J\subseteq J'$ take $j\in J'\setminus J$ and use $C^*$, which also has norm $r$). Then $\chi_{J',l}$ and $\chi_{J\setminus\{j\},k}$ do not depend on $x_j$, so $\E_\nu\ip{\chi_{J,k}}{C\chi_{J',l}}=\E_\nu\ip{\phi_j\chi_{J\setminus\{j\},k}}{C\chi_{J',l}}$ with $\phi_j(a)=\sum_t\nu_j(t)\chi(\varsigma_{jk}(a-t))$, where $\nu_j$ is the conditional law of $x_j$ given the other labels under $\nu$. By \eqref{eq:two-root}, $\norm{\phi_j}^2=\norm{\nu_j}^2_{\ell^2}-\frac1p\le\max\nu_j-\frac1p$. Under $\mu$ the conditional law of $x_j$ is uniform on a set of at least $p2^{-d^0_j}(1-e_{d^0_j}(p,n))$ values, and the density of $\nu$ with respect to $\mu$ has ratio at most $R_\nu$, so $\max\nu_j\le R_\nu2^{d^0_j}/(p(1-e_{d^0_j}(p,n)))$ (\cref{lem:graphs:vertex}\ref{it:vertex:dens} for $G^+$). Hence $\norm{\phi_j}\le r\theta_j$, and as $|\chi|\le1$ the term is at most $r^2\theta_{\max}$ in modulus. There are at most $(2^{r_k}-1)(2^{r_l}-1)$ pairs $(J,J')$, and the Schur test for the symmetric matrix $((2^{r_k}-1)(2^{r_l}-1))_{kl}$ bounds their total by $r^2\theta_{\max}\rho_{\rm row}|w|^2=r\eps_{\ne}|w|^2$. \emph{Terms with $J=J'$.} For $J\subseteq N(k)\cap N(l)$, $\E_\nu\ip{\chi_{J,k}}{C\chi_{J,l}}=(\eps_J)_k(\eps_J)_lt_J$, so these terms sum to $\sum_Jt_J|\eps_J\cdot w|^2$; the singletons contribute nothing by (c). (c) If $p\equiv3\pmod4$, $C$ is real antisymmetric ($\chi(-1)=-1$), so $\ip g{Cg}=0$ for real $g$. If $J=\{j\}$, substituting $a\mapsto a+x_j$, $b\mapsto b+x_j$ and then $b=au$ ($a\ne0$), $p^2S_J=\sum_{a\ne0}\chi(a)^3\sum_u\chi(u)\chi(u-1)=-\sum_{a\ne0}\chi(a)=0$. Always $|S_J|\le\norm{g_J}^2\norm C\le r$. \end{proof} For $p\equiv3\pmod4$ the lemma says that the Paley part of the coupling is of lower order: $|w^*\mathbf Dw|\le r(\eps_{\ne}+\eps_{\rm rem})|w|^2$. For $p\equiv1\pmod4$ the diagonal terms $t_J$ with $|J|\ge2$ survive, and \cref{subsec:advance:parity} bounds them. \begin{lemma}[The coupling block]\label{cor:spec2:coupling} Assume $e_\Delta(p,2n)<1$ and $\eps_V<1$, and take the coupling data of instance \textup{(A)}. Let the following numbers be given. \begin{itemize} \item $R_+\ge\sup_{\mathcal I^+}\varrho$; for instance $R_+=\Rcut$ (\cref{lem:spec:cutkernel}(c)), or $R_+$ of \cref{prop:spec2:mucentre}\ref{it:centre:sup}. \item $\eps_H$ with $\widetilde\Hmat\preceq\Hmat+\eps_HI$; for instance $\eps'_H+\eps_X$ (\cref{lem:spec2:gram}), or its minimum with $\eps^{\rm loc}_H$ of \cref{lem:push:conditionalgram}. \item $\Gamma_E$ with $\E_{m_p}\norm{\sum_kw_kE_k(\cdot;x)}^2\le\Gamma_E|w|^2$ for all $w$; for instance $\hat E^2$ (\cref{lem:spec2:paley}(a)), or its minimum with the completion-variance bound $\Gamma^{\rm loc}_E$ of \cref{lem:projection-diagonal}. \item If $p\equiv1\pmod4$, a number $\bar\zeta\ge0$ with $|t_J|\le\bar\zeta r$ for every $J$ with $|J|\ge2$ that is not coverable; \cref{subsec:advance:parity} supplies admissible values. \item $\Lambda_+\ge\lambda_{\max}(\Hmat^+)$, $\Lambda_{\rm nc}\ge\lambda_{\max}(\Hmat^{\rm nc})$, $\Lambda_D\ge\norm{\Delta^E}$ and $\bar\lambda(\Hmat)\ge\lambda_{\max}(\Hmat)$. \end{itemize} Put $\eps_{\rm par}=\one_{p\equiv1(4)}\bar\zeta\Lambda_{\rm nc}$, $\eps_{\rm rem}=\eps_{\rm rem}(\Gamma_E)$ of \eqref{eq:spec:rem} with this $\eps_H$, and \begin{equation}\label{eq:spec:etaB} \eta_B=\Big(\frac{R_+p}{p-1}-1\Big)\Lambda_+ +\frac{R_+p}{p-1}\big(\eps_H+\eps_{\ne}+\eps_{\rm rem}+\eps_{\rm par}\big) +\eps_V\Lambda_D^2+2\Lambda_D\eta_Q . \end{equation} Then for every $\xi\ne0$ \[ \mathbf M(\xi)\preceq\frac1{p-1}\Big[\widetilde\Hmat+\one_{p\equiv1(4)}\Hmat^{\rm cov} +(\eps_{\ne}+\eps_{\rm rem}+\eps_{\rm par})I\Big]\preceq\frac{\Lambda_M}{p-1}\,I, \] with $\Lambda_M=\Lambda_++\eps_H+\eps_{\ne}+\eps_{\rm rem}+\eps_{\rm par}$, and for every complex $F_V=\sum_kg_k(x_k)\in\mathcal V$ \begin{equation}\label{eq:spec:coupling} \norm{(I-\Pi_{\mathcal V})\Op F_V}^2_\mu\le r^2\sum_{\xi\ne0}\hat g(\xi)^* \big(\Hmat^+-\Azero(\xi)^*\Azero(\xi)+\eta_BI\big)\hat g(\xi). \end{equation} \end{lemma} \begin{proof} \emph{The matrix $\mathbf M$.} By \cref{lem:spec2:paley}(b),(c), and since $|t_J|\le r$ for every $J$, $|t_J|\le\bar\zeta r$ for the non-coverable $J$, and both $\Hmat^{\rm cov}$ and $\Hmat^{\rm nc}$ are Gram sums, \[ |w^*\mathbf Dw|\le r\big(\one_{p\equiv1(4)}\big(w^*\Hmat^{\rm cov}w+\bar\zeta\,w^*\Hmat^{\rm nc}w\big) +(\eps_{\ne}+\eps_{\rm rem})|w|^2\big), \] and $\bar\zeta w^*\Hmat^{\rm nc}w\le\bar\zeta\Lambda_{\rm nc}|w|^2$. Multiply by $\frac p{p-1}|c_\xi|=\frac p{p-1}r$ and use $pr^2=1$; as $\mathbf M(\xi)$ is Hermitian (\cref{lem:coupling-modes}) this gives the first inequality, and \cref{lem:spec2:gram} ($\widetilde\Hmat\preceq\Hmat+\eps_HI$) with $\Hmat^+\preceq\Lambda_+I$ gives the second. \emph{Step 1.} By \cref{lem:coupling-modes} and the first part, $\norm{\Op F_V}^2_\mu\le R_+\sum_\xi\hat g^*\mathbf M\hat g\le r^2\frac{R_+p}{p-1}\sum_\xi\hat g^*\big[\Hmat^++(\eps_H+\eps_{\ne}+\eps_{\rm rem}+\eps_{\rm par})I\big]\hat g$, and $\frac{R_+p}{p-1}\Hmat^+\preceq\Hmat^++(\frac{R_+p}{p-1}-1)\Lambda_+I$, because $\Hmat^+\succeq0$ and $R_+p/(p-1)\ge1$ ($\sup\varrho\ge\E_\mu\varrho=1$). \emph{Step 2.} Let $v=\sum_kv_k(x_k)$ with $\hat v(\xi)=\mathbf Q(\xi)\hat g(\xi)$ for $\xi\ne0$ and $\hat v(0)=0$. Then $v\in\mathcal V$, with no reality condition on its coefficients. By \cref{lem:spec:degone}(a), $\ip v{\Op F_V}_\mu=\sum_\xi|\mathbf Q\hat g|^2$, and by \cref{lem:spec:degone}(c), $\norm v^2\le(1+\eps_V)\sum_\xi|\mathbf Q\hat g|^2$. Hence $\norm{\Pi_{\mathcal V}\Op F_V}^2\ge|\ip v{\Op F_V}|^2/\norm v^2\ge(1+\eps_V)^{-1} \sum_\xi|\mathbf Q(\xi)\hat g(\xi)|^2$ (trivially if the sum is $0$). \emph{Conclusion.} By \cref{lem:spec:degone}(b), $|\mathbf Q\hat g|^2/r^2=|(\Azero+E_Q)\hat g|^2\ge|\Azero\hat g|^2-2\Lambda_D\eta_Q|\hat g|^2=:X-Y$, and since $\eps_V<1$ and $X\le\Lambda_D^2|\hat g|^2$, \[ (1+\eps_V)^{-1}|\mathbf Q\hat g|^2/r^2\ge(1-\eps_V)\max(0,X-Y)\ge X-Y-\eps_VX \ge\hat g^*\Azero^*\Azero\hat g-(2\Lambda_D\eta_Q+\eps_V\Lambda_D^2)|\hat g|^2 . \] By Pythagoras, $\norm{(I-\Pi_{\mathcal V})\Op F_V}^2=\norm{\Op F_V}^2-\norm{\Pi_{\mathcal V}\Op F_V}^2$; collecting the terms gives \eqref{eq:spec:coupling}. \end{proof} The proof uses $\sup\varrho$ only in Step~1, where $\Op F_V=\varrho\cdot\mathcal PF_V$. The other occurrences of $\Rcut$, through $R_\nu$ in $\theta_j$ and in the constant $\zeta$ of \cref{subsec:advance:parity}, bound ratios of counts; the number $R_+$ used in Step~1 is not substituted for $\Rcut$ in them. For $p\equiv3\pmod4$ the model is $\Hmat^+=\Hmat$ and $\eps_{\rm par}=0$. \subsection{Variance of completion counts}\label{subsec:spec:completion-variance} The coupling inputs $\eps_H$ and $\Gamma_E$ measure how far the conditional density $pP_k(\cdot\mid x)$ of instance (A) is from the normalized indicator of $\Phi_k(x)$, that is, how much the number of completions of the opposite half varies with the value $a=x'_k$. The bounds of \cref{lem:spec2:gram,lem:spec2:paley} use only the range of the completion counts, through $R'_k$, which is a product over all vertices. At the completed-root cuts LL20 (the chamber cut in coordinate~0 of the two-layer root) and LL22 (its layer cut), defined in \cref{subsec:push:layer72spectral} (see also \cref{lem:upper-completed-root}), this range bound is too crude for the test \eqref{eq:spectral-test}. The estimate below integrates the internal neighbourhood $S$ of $k$ exactly: conditionally on the labels $z$ of the vertices outside $S\cup\{k\}$, whose law does not depend on $a$, the count is, up to the edges inside $S$ and to coincidences, a product of one-variable counts, and each depends on $a$ only through one Paley factor of norm $r$; the edges inside $S$ are expanded in characters and bounded by matchings or by the two-variable sum of \cref{thm:dl:H2}. Minkowski's inequality then averages over $z$. The result is a bound for the relative variance of the counts, which enters the coupling block through the two lemmas that follow it. Fix $x\in\mathcal I^+$ and $k\in U^+$, and let $C_k(a)$ be the number of $x'\in\mathcal I^+$ with $K(x,x')=1$ and $x'_k=a$ (the count $N_k(a)$ of instance (A)); it vanishes off $\Phi_k=\Phi_k(x)$. Write $\E_{\Phi_k}$, $\Var_{\Phi_k}$ for the uniform probability on $\Phi_k$, and let $v_k(x)=\Var_{\Phi_k}(C_k)/(\E_{\Phi_k}C_k)^2$ be the \emph{relative completion variance}. We use count errors $(\epsilon^+_t)_{t\ge0}$ and $(\epsilon^-_t(z))_{t,z\ge0}$, nondecreasing in $t$ and $z$, such that every set $\Phi$ of \cref{lem:extension} with $t$ roots satisfies $|\Phi|\le p2^{-t}(1+\epsilon^+_t)$, whatever its excluded set, and $|\Phi|\ge p2^{-t}(1-\epsilon^-_t(z))$ if it excludes at most $z$ labels. By \cref{lem:extension}\ref{it:ext:upper},\ref{it:ext:lower} the graded errors $e^+_t$, $e^-_t(z)$ of \eqref{eq:graphs:graded} are such errors, and so is every larger choice. The certificates use $\epsilon^+_t=c_tr+\binom t2r^2$ and $\epsilon^-_t(z)=\epsilon^+_t+z2^tr^2$ with $c_t=\sum_{j=3}^t\binom tj(j-1)$. These are larger: $c_t-a_t=b_t-\binom t2$ is the number of even-size subsets of $\{1,\dots,t\}$ with at least four elements (with $a_t$, $b_t$ as in \eqref{eq:graphs:graded}; proof of \cref{lem:extension}), so $\epsilon^+_t-e^+_t=\epsilon^-_t(z)-e^-_t(z)=(c_t-a_t)(r-r^2)\ge0$; and $c_t$, $\binom t2$ are nondecreasing in $t$. \begin{lemma}[Completion variance]\label{lem:push:localvariance} Assume $e_\Delta(p,2n)<1$, and let $x\in\mathcal I^+$ and $k\in U^+$. \begin{enumerate}[label=\textup{(\alph*)}] \item \emph{(Range.)} If $00$, then \begin{equation}\label{eq:push:localvariance} v_k(x)\le\big(\eps^{\rm loc}_k/\ell^{\rm loc}_k\big)^2 . \end{equation} \end{enumerate} \end{lemma} The bound depends on $x$ only through the graph data, so it is uniform in $x$. If $G^+[S]$ is a forest, every nonempty matching is admissible in (i) with $b=0$: a directed cycle of the contracted graph, followed through the matched edges, would be a cycle of $G^+[S]$. If $G^+[S]$ is a four-cycle together with isolated vertices, $b=1$ exactly when $H$ is the four-cycle and $|M|=2$, and $b=0$ otherwise. These are the two geometries of the root cuts: each internal neighbourhood of $\mathrm{LL20}$ is a $K_{2,2}$ together with isolated vertices, and each internal neighbourhood of $\mathrm{LL22}$ is a forest (the evaluator of \cref{rem:spectral-criterion:certificate} checks that every internal neighbourhood is of one of these two kinds). \begin{proof} (a) $(u-C)(C-l)\ge0$ gives $\E C^2\le(u+l)\bar C-ul$, so $\Var C\le(u-\bar C)(\bar C-l)$, and $(u-l)^2\bar C^2-4ul(u-\bar C)(\bar C-l)=((u+l)\bar C-2ul)^2\ge0$. For the second statement take the uniform probability on $\Phi_k$ and $C=C_k$, which lies in $[L_k,U_k]$ with $U_k/L_k=R'_k$ (instance (A) of \cref{subsec:spec:coupling}). (b) \emph{Conditioning.} The vertices of $R$ are not adjacent to $k$. Let $\mathcal Z$ be the set of labellings $z$ of $R$ that are injective, avoid $x(U^+)$, and satisfy the edges inside $R$ and the cross constraints of $R$ with $x$; it does not depend on $a$. A completion counted by $C_k(a)$ is a triple $(a,y,z)$ with $z\in\mathcal Z$, $a\notin z(R)$ and a labelling $y$ of $S$ satisfying the remaining constraints. For $i\in S$ the constraints of $y_i$ with the fixed labels are its $r_i$ cross constraints with $x$ and its edges to $R$, $m_i$ in all, with distinct roots; let $\Phi^z_i$ be the set of values outside $x(U^+)\cup z(R)$ (at most $2n$ labels) satisfying them, and $A_i=2^{m_i}|\Phi^z_i|/p$, so that $\alpha^-_i\le A_i\le\alpha^+_i$. For $a\in\Phi_k\setminus z(R)$ let $\mathcal A_i(a)=\{y\in\Phi^z_i:y\ne a,\ \text{the constraint of the edge between $i$ and $k$ holds}\}$, a set with $m_i+1$ distinct roots, and $\rho_i=2^{m_i+1}\one_{\mathcal A_i(a)}$ on $\Fp$. Then $q_i:=\E\rho_i=2^{m_i+1}|\mathcal A_i(a)|/p\le\alpha^{++}_i$ and $\norm{\rho_i}^2_2=2^{m_i+1}q_i\le2^{m_i+1}\alpha^{++}_i$. Define the normalized count $\mathcal H(a,z)=2^{|E(G^+[S])|}\prod_{i\in S}(2^{m_i+1}/p)\cdot\#\{y\}$ for $a\notin z(R)$, and $\mathcal H(a,z)=0$ if $a\in z(R)$. Then $C_k(a)=c_0\sum_{z\in\mathcal Z}\mathcal H(a,z)$ with a constant $c_0>0$ independent of $a$ and $z$, and $\mathcal Z\ne\emptyset$ because $C_k\not\equiv0$ (\cref{lem:spec:cutkernel}(c)). For $a\notin z(R)$, with $y$ uniform on $\Fp^S$, \[ \mathcal H(a,z)=\E_y\Big[\prod_{i\in S}\rho_i(y_i)\,\one[y\ \text{injective}] \prod_{e\in E(G^+[S])}\big(1+\chi_e(y)\big)\Big], \] where $\chi_e(y)=\chi(y_w-y_{w'})$ for the edge $e=(w',w)$: on injective $y$, $1+\chi_e(y)$ is twice the indicator of the edge constraint $y_w-y_{w'}\in\Qsq$. \emph{The linear part.} For $a\in\Phi_k\setminus z(R)$, $q_i(a)=\frac{2^{m_i}}p\sum_{y\in\Phi^z_i}\big(1+s_i\chi(y-a)-\one_{y=a}\big) =A_i+f_i(a)-\frac{2^{m_i}}p\one_{\Phi^z_i}(a)$, with $s_i\in\{\pm1\}$ the sign of the constraint of the edge between $i$ and $k$ and $f_i=s_i2^{m_i}C\one_{\Phi^z_i}$. By \cref{lem:spec:gauss}, $\norm{f_i}^2_2\le4^{m_i}r^2|\Phi^z_i|/p=2^{m_i}A_ir^2$. The uniform probability on $\Phi_k$ has density at most $\kappa_\Phi$ with respect to the uniform probability on $\Fp$, so $\norm{(q_i-A_i)\one_E}_{L^2(\Phi_k)}\le L_i$ on $E=\Phi_k\setminus z(R)$. There $q_j\le\alpha^{++}_j$ and $A_j\le\alpha^+_j\le\alpha^{++}_j$; telescoping $\prod_iq_i-\prod_iA_i$ and Minkowski give $\norm{(\prod_iq_i-\prod_iA_i)\one_E}_{L^2(\Phi_k)}\le\mathrm{Lin}_k$. \emph{Coincidences.} Let $\mathcal H'$ be the expression for $\mathcal H$ with the indicator of injectivity replaced by the indicator of injectivity inside $S_0$ and inside $S_1$. The product over $E(G^+[S])$ lies in $[0,2^{|E(G^+[S])|}]$, and on injective $y$ the two agree. Hence $0\le\mathcal H'-\mathcal H\le2^{|E(G^+[S])|}\sum\E_y[\prod_i\rho_i(y_i)\one_{y_i=y_j}]$ over the pairs $\{i,j\}$ with one vertex in each part. For any pair, $\E_y[\prod_l\rho_l\one_{y_i=y_j}]=\prod_lq_l\cdot|\mathcal A_i\cap\mathcal A_j|/(|\mathcal A_i||\mathcal A_j|) \le\prod_lq_l\cdot\min(\kappa_i,\kappa_j)/p$, since $\mathcal A_i$ excludes at most $2n$ labels and so $|\mathcal A_i|\ge p/\kappa_i$. Expanding the product over the edges, $\mathcal H'=\sum_{H\subseteq E(G^+[S])}T_H$ with \[ T_H=\E_y\Big[\prod_{i\in S}\rho_i(y_i)\,\one[y\ \text{injective inside}\ S_0\ \text{and inside}\ S_1] \prod_{e\in H}\chi_e(y)\Big], \] and $\prod_iq_i-T_\emptyset$ lies in $[0,\prod_lq_l\sum\min(\kappa_i,\kappa_j)/p]$, the sum over the pairs inside one part. These two lists of pairs are disjoint, so on $E$ \[ \Big|\mathcal H-\prod_iq_i-\sum_{\emptyset\ne H}T_H\Big|\le\mathrm{Coll}_k . \] \emph{Matching bounds.} Let $M\subseteq H$ be a matching as in (i). Freeze the labels of $S\setminus V(M)$. The factors of $T_H$ that involve a matched vertex and an unmatched one (characters of edges of $H$, and the indicators of distinctness inside a part) are functions of the matched label of modulus at most one; absorb them into $\rho_i$, $i\in V(M)$, which does not increase $\norm{\rho_i}_2$. The remaining kernel between the labels of $V(M)\cap S_0$ and of $V(M)\cap S_1$ is a product of signed characters of the core $H[V(M)]$, with the matching edges as diagonal; all edges of $H$ join the two parts, and the distinctness inside each part restricted to $V(M)$ is the projection onto injective tuples. By \cref{lem:matching:kernel}(a) (if $b=0$) and (b), the compression of this kernel by these projections has norm at most $2^br^{|M|}$, so the inner expectation over the matched labels is at most $2^br^{|M|}\prod_{i\in V(M)}\norm{\rho_i}_2$ in modulus, by Cauchy--Schwarz. The remaining factors among the unmatched labels have modulus at most one, and $\E_y\prod_{i\notin V(M)}\rho_i(y_i)=\prod_{i\notin V(M)}q_i\le\prod_{i\notin V(M)}\alpha^{++}_i$. Hence $|T_H|\le B_H(M)$. \emph{Two-variable bounds.} Let $uv\in H$, $u\in S_0$, $v\in S_1$, and freeze all labels except $y_u,y_v$. Off $x(U^+)\cup z(R)\cup\{a\}$, which contains its roots, $\rho_u(y_u)$ equals the soft product $\tilde\rho_u(y_u)=\prod_\beta(1+s_\beta\chi(y_u-\beta))$ over its $d_u$ constraints with the fixed labels and $a$ (the \emph{optional centres}; a centre here is a label $\beta$ in a factor $\chi(y_u-\beta)$, not a principal law); the characters of the other edges of $H$ at $u$ have the frozen labels of $S_1$ as centres (the $f_u$ \emph{forced centres}). The optional centres lie in $x(U^+)\cup z(R)\cup\{a\}$ and the forced centres are labels of $\mathcal A_w$, $w\in S_1$, distinct by the injectivity inside $S_1$; so all $d_u+f_u$ centres at $u$ are distinct, and likewise at $v$. Expanding the optional factors, the average over $(y_u,y_v)\in\Fp^2$ of $\tilde\rho_u\tilde\rho_v$ times the characters is a sum of $\binom{d_u}i\binom{d_v}j$ averages $\E_{y,y'}\chi(f(y)g(y')(y'-y))$ with $\deg f=i+f_u$, $\deg g=j+f_v$, each multiplied by a sign. If $\deg g=0$ the sum over $y'$ vanishes, and similarly for $\deg f=0$; if $\deg f=\deg g=1$ the two-root identity \eqref{eq:two-root} gives modulus at most $p$; otherwise \cref{thm:dl:H2} gives modulus at most $p\,\mathcal B(\cdot,\cdot,s)\le p\,\mathcal B(\cdot,\cdot,0)$. So this average is at most $r^2(C_0+rC_1+r^2C_2)$. Restoring the excluded values: $\tilde\rho_u\ge0$, it agrees with $2^{d_u}$ times the indicator of its constraints off its $d_u$ roots and is at most $2^{d_u}$ at the roots, so $\E\tilde\rho_u\le s_u$; each of $y_u$, $y_v$ must avoid at most $2n$ labels (the excluded labels and the frozen labels of its own part); so the restriction changes the average by at most $\frac{2n}p(2^{d_u}s_v+2^{d_v}s_u)$. The edge $uv$ vanishes on the diagonal, and the coincidences between the two parts are charged in $\mathrm{Coll}_k$. The other factors are bounded as in the matching case. Hence $|T_H|$ is at most the bound (ii), and so $|T_H|\le P_H$. \emph{Averaging.} On $E$, $|\mathcal H-\prod_iA_i|\le|\prod_iq_i-\prod_iA_i|+\mathrm{Pair}_k+\mathrm{Coll}_k$. On $\Phi_k\setminus E$ (where $a\in z(R)$), $\mathcal H=0$ and $|\mathcal H-\prod_iA_i|\le\prod_i\alpha^+_i$, while the uniform probability of this set is at most $|R|/|\Phi_k|\le|R|\kappa_\Phi/p$. Hence $\norm{\mathcal H(\cdot,z)-\prod_iA_i}_{L^2(\Phi_k)}\le\eps^{\rm loc}_k$ for every $z\in\mathcal Z$. Let $\bar{\mathcal H}=\E_z\mathcal H(\cdot,z)$ and $\bar A=\E_z\prod_iA_i\ge\prod_i\alpha^-_i$, with $z$ uniform on $\mathcal Z$. By Minkowski, $\norm{\bar{\mathcal H}-\bar A}_{L^2(\Phi_k)}\le\eps^{\rm loc}_k$, so $\E_{\Phi_k}\bar{\mathcal H}\ge\bar A-\eps^{\rm loc}_k\ge\ell^{\rm loc}_k>0$ and $\Var_{\Phi_k}\bar{\mathcal H}\le\norm{\bar{\mathcal H}-\bar A}^2\le(\eps^{\rm loc}_k)^2$. As $C_k=c_0|\mathcal Z|\bar{\mathcal H}$, the relative variance of $C_k$ is that of $\bar{\mathcal H}$. \end{proof} The relative variance enters the coupling block in two ways: through the error functions $E_k$ (the input $\Gamma_E$) and through the Gram matrix of the conditional densities (the input $\eps_H$). In \cref{lem:projection-diagonal,lem:push:conditionalgram} below, $\bar v_k$ is any number with $v_k(x)\le\bar v_k$ for every $x$, for instance the minimum of the bounds of \cref{lem:push:localvariance}(a) and (b). \begin{lemma}[Projection-error diagonal]\label{lem:projection-diagonal} In instance \textup{(A)}, for every $x\in\mathcal I^+$ and $k\in U^+$, \begin{equation}\label{eq:push:projectiondiagonal} \norm{E_k(\cdot;x)}^2\le\frac{n4^{r_k}}p+\frac{2^{r_k}}{1-\hat e_k}\big(\bar v_k+\hat e_k^2\big), \end{equation} with $\hat e_k=e_{r_k}(p,n)$. Consequently $\Gamma^{\rm loc}_E$, the sum over $k$ of the right side, satisfies $\norm{\sum_kw_kE_k(\cdot;x)}^2\le\Gamma^{\rm loc}_E|w|^2$ for every $x$, and $\min(\Gamma^{\rm loc}_E,\hat E^2)$ is an admissible input $\Gamma_E$ of \cref{cor:spec2:coupling}. \end{lemma} \begin{proof} Let $\alpha=|\Phi_k|/p$ and $\bar C_k=\E_{\Phi_k}C_k$. On $\Phi_k$, $pP_k=\alpha^{-1}C_k/\bar C_k$ and $\varphi_k=2^{r_k}$, so $E_k=\alpha^{-1}(C_k/\bar C_k-1)+(\alpha^{-1}-2^{r_k})$; off $\Phi_k\cup x(U^+)$, $E_k=0$; and $|E_k|\le2^{r_k}$ on $x(U^+)$. Since $\sum_{\Phi_k}(C_k/\bar C_k-1)=0$, the cross term vanishes and $\norm{E_k}^2\le\alpha^{-1}v_k+\alpha^{-1}(1-2^{r_k}\alpha)^2+n4^{r_k}/p$. Finally $\alpha^{-1}\le2^{r_k}/(1-\hat e_k)$ and $|1-2^{r_k}\alpha|\le\hat e_k$. The second statement is Cauchy--Schwarz over $k$, and the minimum of two admissible inputs is admissible. \end{proof} A \emph{weighted Schur bound} of a nonnegative symmetric matrix $Y$ is a number $\max_k(Yw)_k/w_k$ for a vector $w$ with positive entries. It bounds the norm of every Hermitian matrix $X$ with $|X_{kl}|\le Y_{kl}$, since $|u^*Xu|\le\sum Y_{kl}|u_k||u_l|\le\sum_k|u_k|^2(Yw)_k/w_k$. \begin{lemma}[Conditional-density Gram refinement]\label{lem:push:conditionalgram} In instance \textup{(A)} put $y_k=2^{r_k}\bar v_k/(1-\hat e_k)$, let $Y$ be the matrix with $Y_{kk}=y_k$, $Y_{kl}=\min\{(y_ky_l)^{1/2},\Upsilon_{kl}\delta'_k\delta'_l\}$ for consistent $k\ne l$ and $Y_{kl}=0$ otherwise, and let $\Gamma_D$ be the smaller of $\sum_ky_k$ and a weighted Schur bound of $Y$. Let $h_0$ be a weighted Schur bound of the matrix $(\beta_{kl})$ of \eqref{eq:spec:beta}. Then \begin{equation}\label{eq:push:conditionalgram} \widetilde\Hmat\preceq\Hmat+\eps^{\rm loc}_HI,\qquad \eps^{\rm loc}_H=h_0+2\big(\Gamma_D(\bar\lambda(\Hmat)+h_0)\big)^{1/2}+\Gamma_D . \end{equation} So $\min(\eps'_H+\eps_X,\eps^{\rm loc}_H)$ is an admissible input $\eps_H$ of \cref{cor:spec2:coupling}. \end{lemma} \begin{proof} Fix $x$. As in the proof of \cref{lem:spec2:gram}, $\Psi_k=\psi_k+D_k$ with $D_k=(1+\psi_k)\delta_k=\alpha_k^{-1}\one_{\Phi_k}(C_k/\bar C_k-1)$, $\alpha_k=|\Phi_k|/p$ and $\bar C_k=\E_{\Phi_k}C_k$. The Gram matrix of the $\psi_k$ differs from $\Hmat$ entrywise by at most $\beta_{kl}$, so its norm distance from $\Hmat$ is at most $h_0$, and the synthesis operator $A_x\colon w\mapsto\sum_kw_k\psi_k$ satisfies $\norm{A_xw}^2\le w^*\Hmat w+h_0|w|^2$, and so $\norm{A_xw}^2\le(\bar\lambda(\Hmat)+h_0)|w|^2$. Next $\norm{D_k}^2=\alpha_k^{-1}v_k\le y_k$; for consistent $k\ne l$, $|\ip{D_k}{D_l}|\le\min\{\norm{D_k}\norm{D_l},\Upsilon_{kl}\delta'_k\delta'_l\}$, by the intersection count of the proof of \cref{lem:spec2:gram}; and for inconsistent pairs the supports are disjoint. So the synthesis operator $D_x\colon w\mapsto\sum_kw_kD_k$ has $\norm{D_x}^2\le\Gamma_D$ (the trace bound $\norm{D_x}^2\le\sum_k\norm{D_k}^2$ needs no positivity). Finally $w^*\widetilde\Hmat w=\E_{m_p}\norm{A_xw+D_xw}^2\le\E\big(\norm{A_xw}^2+2\norm{A_xw}\norm{D_xw} +\norm{D_xw}^2\big)$, which is at most $w^*\Hmat w+\eps^{\rm loc}_H|w|^2$. \end{proof} At the root cuts the certificates take, at each threshold, the smaller of each refined input and the standard one: $\Gamma_E=\min(\Gamma^{\rm loc}_E,\hat E^2)$, with $\bar v_k$ the bound (b) of \cref{lem:push:localvariance} (each $P_H$ the smaller of its matching and two-variable bounds), and $\eps_H=\min(\eps'_H+\eps_X,\eps^{\rm loc}_H)$, with $\bar v_k$ the minimum of the bounds (a) and (b); they then recompute $\eps_{\rm rem}$ and $\eta_B$ and repeat the exact positive-semidefiniteness tests of \eqref{eq:spectral-test}. All these inputs are admissible (\cref{lem:spectral-monotone}(d)), with the Schur weights fixed at the threshold. \subsection{The character expansion}\label{subsec:spec:perp} The part of the cut kernel orthogonal to the degree-one space is handled by expanding it in the characters of its cross pairs. Each set $S$ of cross pairs contributes one operator $T_S$; sets whose pairs all share one endpoint (\emph{stars}) are computed exactly below, and the remaining sets are grouped into a nonstar term and a collision term, bounded in \cref{sec:extraction}. For a cross pair $e=(j,k)\in E_\times$ put $\chi_e(x,x')=\chi(\varsigma_{jk}(x'_k-x_j))$, and for $S\subseteq E_\times$ put $\chi_S=\prod_{e\in S}\chi_e$; let $T_S$ be the operator on $L^2(\mu)$ with kernel $\chi_S$ relative to $\mu\otimes\mu$, $(T_Sh)(x)=\E_{x'\sim\mu}[\chi_S(x,x')h(x')]$. Let $J(S)$ and $K(S)$ be the sets of $x$-endpoints and $x'$-endpoints of $S$. A nonempty $S$ is a \emph{column star} if $|K(S)|=1$ (all its pairs have the same $x'$-endpoint), a \emph{row star} if $|J(S)|=1$, and a \emph{nonstar} otherwise; single pairs are stars of both kinds. The \emph{transpose} of $S$ is $S^{\mathsf t}=\{(k,j):(j,k)\in S\}\subseteq E_\times$ (\cref{lem:spec:elementary}). Put \[ K_0(x,x')=\one\{x(U^+)\cap x'(U^+)=\emptyset\}\prod_{e\in E_\times}\big(1+\chi_e(x,x')\big), \qquad Z_0=\E_{\mu\otimes\mu}K_0, \] let $T_{\rm ns}=\sum_{S\ \rm nonstar}T_S$, and let $T_{\rm coll}$ be the operator with the kernel $\one\{x(U^+)\cap x'(U^+)\ne\emptyset\}\prod_{e\in E_\times}(1+\chi_e(x,x'))$. We use the same letter for a kernel and its operator relative to $\mu\otimes\mu$. \begin{lemma}[Expansion]\label{lem:spec:expansion} On $\mathcal I^+\times\mathcal I^+$, $K_0=2^{m_\times}K$, so $Z_0=2^{m_\times}Z$ and $\Op=K_0/Z_0$; and, as operators on $L^2(\mu)$, \begin{equation}\label{eq:record:root-kernel} K_0=\one\otimes\one+\sum_{S\ \rm star}T_S+T_{\rm ns}-T_{\rm coll}. \end{equation} All these kernels are real; the kernel of $T_{\rm coll}$ is nonnegative and symmetric, and $T_S^*=T_{S^{\mathsf t}}$ for every $S$. \end{lemma} \begin{proof} $\prod_e(1+\chi_e)=\sum_S\chi_S$ identically, and $\chi_\emptyset=1$ gives $\one\otimes\one$. If $x(U^+)\cap x'(U^+)=\emptyset$, then $x'_k\ne x_j$ for every pair, and $1+\chi(y)=2\Ap(y)$ for $y\ne0$, so the product is $2^{m_\times}K$ by \eqref{eq:spec:K}; otherwise $K=0$ and $K_0=0$. Each factor of the collision kernel lies in $\{0,1,2\}$. Exchanging $x$ and $x'$ maps $\chi_e$, $e=(j,k)$, to $\chi(\varsigma_{jk}(x_k-x'_j))=\chi(\varsigma_{kj}(x'_j-x_k))=\chi_{(k,j)}$, because $\varsigma_{kj}=-\varsigma_{jk}$ (\cref{lem:spec:elementary}); this gives the symmetry of the collision kernel and $T_S^*=T_{S^{\mathsf t}}$. \end{proof} For $x\in\mathcal I^+$ and $t\in\Fp$ let $\varphi_k(t;x)=\prod_{j\in N(k)}(1+\chi(\varsigma_{jk}(t-x_j)))$ as in \cref{subsec:spec:coupling}, $h_{\star,k}(x)=\E_t\varphi_k(t;x)-1$, and let $h_\star=\sum_kh_{\star,k}$; this is the star function of \eqref{eq:star-function} in \cref{sec:dl}, with its centre $t$ integrated out. The \emph{standard star constants} are \[ P_{\rm st}=r^2\sum_{k\in U^+}\binom{r_k}2,\qquad W_{\rm st}=r\sum_{k\in U^+}\sum_{s=3}^{r_k}\binom{r_k}s(s-1). \] \begin{lemma}[Stars]\label{lem:spec:stars} Assume $e_\Delta(p,2n)<1$. \begin{enumerate}[label=\textup{(\alph*)}] \item Let $S=J\times\{k\}$ be a column star, $\emptyset\ne J\subseteq N(k)$, and $h\in L^2(\mu)$. Then $(T_Sh)(x)=\E_t[\chi_{J,k}(t;x)\,\E_\mu[h\mid x_k=t]]$. In particular $T_Sh=(\E_\mu h)\,T_S\one$ if $\E_\mu[h\mid x_k]$ is constant, and $T_S\one=(\eps_J)_kw_J$ with $w_J(x)=\E_t\prod_{j\in J}\chi(t-x_j)$; on $\mathcal I^+$, $w_J=0$ if $|J|=1$, $w_J=-q$ if $|J|=2$, and $|w_J|\le(|J|-1)r$ if $|J|\ge3$. \item For a row star $S$, $T_S=(T_{S^{\mathsf t}})^*$ with $S^{\mathsf t}$ a column star, and $T_S\one$ is a constant. \item The column stars at $k$ together map $\one$ to $h_{\star,k}$, and $\sum_{S\ \rm star}T_S\one=h_\star+\E_\mu h_\star$; hence $\ip\one{\sum_{S\ \rm star}T_S\one}_\mu=2\E_\mu h_\star$. \item $|\E_\mu h_\star|\le P_{\rm st}+W_{\rm st}$ and $\norm{h_\star-\E_\mu h_\star}_\mu\le W_{\rm st}$. \end{enumerate} \end{lemma} \begin{proof} (a) $\chi_S(x,x')=\chi_{J,k}(x'_k;x)$ depends on $x'$ only through $x'_k$, which is uniform under $\mu$. The values of $w_J$ are \cref{lem:star-trace}: for $|J|=1$ the sum $\sum_t\chi(t-x_j)$ vanishes, for $|J|=2$ use \eqref{eq:two-root} ($x$ is injective), and for $|J|\ge3$ \cref{thm:weil}. The identity $\chi_{J,k}=(\eps_J)_k\prod_j\chi(t-x_j)$ is the multiplicativity of $\chi$. (b) The first statement is \cref{lem:spec:expansion}. $(T_S\one)(x)=\E_{x'}\prod_{k\in K(S)}\chi(\varsigma_{jk}(x'_k-x_j))$ with $\{j\}=J(S)$; replacing $x'$ by $x'+x_j\one$, which preserves $\mu$, shows that it does not depend on $x$. (c) Summing (a) over $\emptyset\ne J\subseteq N(k)$ gives $\E_t[(\varphi_k(t;x)-1)\cdot1]=h_{\star,k}$. The single pairs contribute $w_{\{j\}}=0$, so the row stars (with at least two pairs) contribute a constant equal to $\sum\ip\one{T_S\one}=\sum\ip{T_{S^{\mathsf t}}\one}\one$, which is the total mean of the column stars with at least two pairs, $\E_\mu h_\star$. (d) By (a), $h_\star=-q\sum_k\sum_{|J|=2}(\eps_J)_k+h^{\ge3}$ with $h^{\ge3}=\sum_k\sum_{|J|\ge3}(\eps_J)_kw_J$, where $|(\eps_J)_k|\le1$. The first term is a constant of modulus at most $P_{\rm st}$, and $\norm{h^{\ge3}}_\infty\le W_{\rm st}$. Hence $h_\star-\E_\mu h_\star=h^{\ge3}-\E_\mu h^{\ge3}$, of norm at most $\norm{h^{\ge3}}_\mu\le W_{\rm st}$. \end{proof} \subsection{Centring at the half-law mean}\label{subsec:spec:centring} The test functions are centred at their mean under the half law $\mu$. Centring at the mean under $m_p$ instead leaves $\E_\mu F_\perp\ne0$, and then every star and every four-cycle can contribute through $\E_\mu F_\perp$; centring at $\E_\mu F$ removes these terms exactly, in exchange for one cross term $2c\ip{\varrho-1}{F_\perp}_\mu$ between the constant and the remainder, which is of second order. Let $\mathcal H_\perp=(\C\one\oplus\mathcal V)^\perp\subseteq L^2(\mu)$. \begin{proposition}[Centring at the $\mu$-mean]\label{prop:spec2:mucentre} Assume $e_\Delta(p,2n)<1$ and $\eps_V<1$. \begin{enumerate}[label=\textup{(\alph*)}] \item\label{it:centre:decomp} For real $F\in L^2(\mu)$ let $c=\E_\mu F$, $F_V=\Pi_{\mathcal V}(F-c)=\sum_kg_k(x_k)$ and $F_\perp=F-c-F_V\in\mathcal H_\perp$. Every $h\in\mathcal H_\perp$ has $\E_\mu[h\mid x_k]=0$ for all $k$; hence $\ip{h'}{T_Sh}_\mu=0$ for $h,h'\in\mathcal H_\perp$ if $S=\emptyset$ or $S$ is a star. Moreover $\ip\one{\Op v}_\mu=0$ for $v\in\mathcal V$, and $\norm F^2_\mu=c^2+\norm{F_V}^2_\mu+\norm{F_\perp}^2_\mu\ge(1-\eps_V)(c^2+\norm g^2+\norm{F_\perp}^2_\mu)$. \item\label{it:centre:form} $Q(F)=c^2+2c\ip{\varrho-1}{F_\perp}_\mu+Q(F_V)+2\ip{F_\perp}{\Op F_V}_\mu+Q(F_\perp)$. \item\label{it:centre:inputs} \emph{(Inputs.)} Let $N_{\rm ns}$, $D_{\rm col}$, $M_\star$ satisfy $\norm{T_{\rm ns}}\le N_{\rm ns}$, $\norm{T_{\rm coll}}\le D_{\rm col}$ and $\norm{h_\star-\E_\mu h_\star}_\mu\le M_\star$, and let $\eps_Z<1$ satisfy $Z_0\ge1-\eps_Z$; for instance $\eps_Z=Z_\star+N_{\rm ns}+D_{\rm col}$ with $2|\E_\mu h_\star|\le Z_\star$, or $\eps_Z=\min(\eps_Z',\eps_Z'')$ for two numbers $\eps_Z',\eps_Z''$ formed in this way from different admissible pairs $(Z_\star,D_{\rm col})$. Put $R_Z=(1-\eps_Z)^{-1}$ and $\eps_\varrho=R_Z(M_\star+N_{\rm ns}+D_{\rm col})$. \begin{enumerate}[label=\textup{(c\arabic*)}] \item\label{it:centre:Z} $Z_0-1=2\E_\mu h_\star+\ip\one{(T_{\rm ns}-T_{\rm coll})\one}_\mu$, and $2^{-m_\times}/Z\le R_Z$. \item\label{it:centre:sup} $\sup_{\mathcal I^+}\varrho\le R_+:=\dfrac{\prod_{i=1}^n\big(1+e_{t_i}(p,2n)\big)} {(1-\eps_Z)\prod_{i\in U^+}\big(1-e_{d^0_i}(p,n)\big)}$, with the deletion degrees $t_i$. \item\label{it:centre:rho} $\norm{\varrho-1}_\mu=\norm{P_0\Op\one}_\mu\le\eps_\varrho$. \item\label{it:centre:perp} $|\ip h{\Op h}_\mu|\le R_Z(N_{\rm ns}+D_{\rm col})\norm h^2_\mu$ for $h\in\mathcal H_\perp$. \item\label{it:centre:cperp} $c^2+2c\ip{\varrho-1}{F_\perp}_\mu+Q(F_\perp)\ge-c_\perp r\norm{F_\perp}^2_\mu$ with $c_\perp=\big(R_Z(N_{\rm ns}+D_{\rm col})+\eps_\varrho^2\big)/r$. \end{enumerate} \item\label{it:centre:standard} \emph{(Standard star inputs.)} The numbers $M_\star=W_{\rm st}$ and $Z_\star=2(P_{\rm st}+W_{\rm st})$ are admissible in \ref{it:centre:inputs}, by \cref{lem:spec:stars}(d). \end{enumerate} \end{proposition} \begin{proof} (a) $h\perp\one$ and $h\perp\mathcal V_k$, and every function of $x_k$ is a constant plus an element of $\mathcal V_k$; so $h$ is orthogonal to all functions of $x_k$. For $S=\emptyset$, $\ip{h'}{T_\emptyset h}=\overline{\E h'}\,\E h=0$. For a column star at $k$, $T_Sh=0$ by \cref{lem:spec:stars}(a); for a row star, $\ip{h'}{T_Sh}=\ip{T_{S^{\mathsf t}}h'}h=0$ by (b) of that lemma. Next $\ip\one{\Op v}=\E_\lambda v(x')=\E_{m_p}v=0$ (\cref{lem:spec:cutkernel}(b),(d)). The three functions $c$, $F_V$, $F_\perp$ are pairwise orthogonal, and \cref{lem:spec:degone}(c) gives $\norm{F_V}^2\ge(1-\eps_V)\norm g^2$. (b) Put $G=F_V+F_\perp$, so $\E_\mu G=0$. As $\Op$ is self-adjoint with $\Op\one=\varrho$, $Q(c+G)=c^2\E_\mu\varrho+2c\ip\varrho G+Q(G)$, with $\E_\mu\varrho=1$, $\ip\varrho G=\ip{\varrho-1}G$ and $\ip{\varrho-1}{F_V}=\E_{m_p}F_V-\E_\mu F_V=0$. (c1) Pair \eqref{eq:record:root-kernel} with $\one$ and use \cref{lem:spec:stars}(c). By \cref{lem:spec:expansion}, $2^{-m_\times}/Z=1/Z_0$. (c2) By the proof of \cref{lem:spec:cutkernel}(b),(c), $\varrho(x)=N(x)/(Z|\mathcal I^+|)$ with $N(x)\le\prod_ip2^{-t_i}(1+e_{t_i}(p,2n))$, and $\sum_it_i=|E(G^+)|+m_\times$. By \cref{lem:graphs:sequential}\ref{it:seq:count} for $G^+$ (any order, $t^0_i\le d^0_i$), $|\mathcal I^+|\ge p^n2^{-|E(G^+)|}\prod_i(1-e_{d^0_i}(p,n))$. With $Z\ge2^{-m_\times}(1-\eps_Z)$ the powers of $p$ and $2$ cancel. (c3) $\E_\mu\varrho=1$, so $\varrho-1=P_0\Op\one$. By \eqref{eq:record:root-kernel} and \cref{lem:spec:stars}(c), $P_0K_0\one=(h_\star-\E_\mu h_\star)+P_0(T_{\rm ns}-T_{\rm coll})\one$, of norm at most $M_\star+N_{\rm ns}+D_{\rm col}$; divide by $Z_0\ge1-\eps_Z$. (c4) By (a) only $T_{\rm ns}-T_{\rm coll}$ contributes to $\ip h{K_0h}$; divide by $Z_0$. (c5) $c^2+2c\ip{\varrho-1}{F_\perp}\ge-\ip{\varrho-1}{F_\perp}^2\ge-\eps_\varrho^2\norm{F_\perp}^2$, and (c4) bounds $Q(F_\perp)$. \end{proof} The proposition reduces the perpendicular block to the four numbers $N_{\rm ns}$, $D_{\rm col}$, $M_\star$ and $\eps_Z$: after centring at the $\mu$-mean no star term survives on $\mathcal H_\perp$, and every nonstar set, a four-cycle included, lies in a class of a nonstar partition, whose classes together are bounded by $N_{\rm ns}$ (\cref{lem:advance:compressed-partition,lem:matching:extractionk}). The two remaining inputs are the coincidence bound $D_{\rm col}$ (\cref{lem:oct24-collision}) and the star marginal $M_\star$ and mean $Z_\star$: the standard constants of \ref{it:centre:standard}, or the sharper ordered-star bounds of \cref{prop:advance:ordered-star,lem:star-mean}. \subsection{Route~A (conditional laws, centring at the half-law mean)}\label{subsec:spec:routeA} Route~A centres test functions at their mean under the half law and works through the conditional law of the opposite half. The theorem packages the estimates of the previous subsections into one finite test at the smallest prime $p_0$; hypotheses (R1)--(R3) name exactly which earlier estimates must be supplied. \begin{theorem}[Spectral criterion centred at the half-law mean (Route~A)]\label{thm:spectral-criterion} Let $(G,\vartheta,U^+,\mathfrak o)$ be spectral data satisfying \textup{(S1)} of \cref{def:spec:data} at $p_0$, put $r_0=p_0^{-1/2}$, and fix a class $\mathfrak c\in\{1,3\}$. Suppose that the following hold at every prime $p\ge p_0$ with $p\equiv\mathfrak c\pmod4$, with $r=p^{-1/2}$, where every input is a function of $r\in(0,r_0]$, and $N_{\rm ns}/r$, $D_{\rm col}/r$, $M_\star/r$, $\eps_Z$, $\Gamma_E$, $\eps_H$ and $\bar\zeta$ are admissible. \begin{enumerate}[label=\textup{(R\arabic*)}] \item \emph{(Degree one.)} $\eta_Q$ and $\eps_V$ are the quantities \eqref{eq:spec:Azero} and \eqref{eq:spec:epsV}, with a fixed $\Lambda_D\ge\norm{\Delta^E_{(\mathfrak c)}}$. \item \emph{(Perpendicular inputs.)} $N_{\rm ns}$, $D_{\rm col}$, $M_\star$ and $\eps_Z<1$ are as in \cref{prop:spec2:mucentre}\ref{it:centre:inputs}, and $\eps_Z(r_0)<1$. \item \emph{(Coupling.)} $\eps_H$, $\Gamma_E$ and, if $\mathfrak c=1$, $\bar\zeta$ satisfy the hypotheses of \cref{cor:spec2:coupling} at $p$, and $\eta_B$ is the quantity \eqref{eq:spec:etaB} formed with them, with $R_+$ of \cref{prop:spec2:mucentre}\ref{it:centre:sup} (or $R_+=\Rcut$) and with fixed bounds $\Lambda_+$, $\Lambda_{\rm nc}$, $\bar\lambda(\Hmat)$ for the matrices of class $\mathfrak c$. \end{enumerate} Put $R_Z=(1-\eps_Z)^{-1}$, $\eps_\varrho=R_Z(M_\star+N_{\rm ns}+D_{\rm col})$ and $c_\perp=\big(R_Z(N_{\rm ns}+D_{\rm col})+\eps_\varrho^2\big)/r$. Let $\cperp,\bar\eta_Q,\bar\eta_B,\bar\eps_V$ be upper bounds of the values of $c_\perp,\eta_Q,\eta_B,\eps_V$ at $r_0$, with $\bar\eps_V<1$. Suppose that for each sign $\pm$ there is $\tau^{\rm sp}_{\mathfrak c,\pm}>0$ with \begin{equation}\label{eq:spectral-test} \mathbf M_{\mathfrak c,\pm}:=\mathbf A_{\mathfrak c,\pm} -\frac{\Hmat^+_{(\mathfrak c)}-(\Delta^E_{(\mathfrak c)})^{\mathsf T}\Delta^E_{(\mathfrak c)}}{\tau^{\rm sp}_{\mathfrak c,\pm}} +\Big(\cperp+\tau^{\rm sp}_{\mathfrak c,\pm}-\bar\eta_Q-\frac{\bar\eta_B}{\tau^{\rm sp}_{\mathfrak c,\pm}}\Big)I\succeq0 . \end{equation} For $\mathfrak c=3$, if $\tau^{\rm sp}_{3,+}=\tau^{\rm sp}_{3,-}$ the two matrices are complex conjugate, so one of the two tests suffices. Let \[ g_{\mathfrak c}\ \ge\ \max_\pm\frac{\cperp+\tau^{\rm sp}_{\mathfrak c,\pm}}{1-\bar\eps_V}. \] Then for every prime $p\ge p_0$ with $p\equiv\mathfrak c\pmod4$: \begin{enumerate}[label=\textup{(\alph*)}] \item $\Op\succeq-g_{\mathfrak c}\,p^{-1/2}I$ on $L^2(\mu_p)$; \item $\norm{P_0\Op P_0}\le g_{\mathfrak c}\,p^{-1/2}$; \item $\norm{\varrho-1}_\mu=\norm{P_0\Op\one}_\mu\le\eps_\varrho(r)$, and $p\,\eps_\varrho(r)^2\le p_0\,\eps_\varrho(r_0)^2$; \item for every $g\ge g_{\mathfrak c}$ with $gr_0<1$, $\Op\preceq(1+B^+/p)I$ with $B^+=p_0\,\eps_\varrho(r_0)^2/(1-gr_0)$. \end{enumerate} \end{theorem} \begin{corollary}[Blocks]\label{cor:spectral-criterion-blocks} In the setting of \cref{thm:spectral-criterion}, let $g\ge g_{\mathfrak c}$ with $gr_0<1$ and $B^+$ as in \textup{(d)}, and let $\Blk$ be a finite set of primes $p\equiv\mathfrak c\pmod4$, all at least $P\ge p_0$, with $\sum_{p\in\Blk}\log p\le L$, and $b=\min\Blk$. Then $\bigotimes_{p\in\Blk}\Op\succeq-d\,b^{-1/2}I$ with $d=g_{\mathfrak c}\exp\big(B^+L/(P\log P)\big)$, and so also with $g$ in place of $g_{\mathfrak c}$. If the hypotheses hold for both classes and $g\ge\max(g_1,g_3)$, the same holds for blocks of primes of both classes. \end{corollary} \begin{proof} By (a) and (d), at every $p\in\Blk$, $-g_{\mathfrak c}p^{-1/2}\le\Op\le1+B^+/p$ and $g_{\mathfrak c}p^{-1/2}\le gr_0<1$. By \cref{lem:spec:tensorcomp}(b) with $\mathcal V_p=L^2(\mu_p)$, $\bigotimes_p\Op\succeq-g_{\mathfrak c}b^{-1/2}\exp(B^+\sum_{p\in\Blk}1/p)$, and $\sum_{p\in\Blk}1/p\le L/(b\log b)\le L/(P\log P)$ by \cref{lem:spec:tensorcomp}(c) and since $X\log X$ increases. For both classes use $\max(g_1,g_3)$ in place of $g_{\mathfrak c}$, and the larger of the two values of $B^+$. \end{proof} \begin{proof}[Proof of \cref{thm:spectral-criterion}] Fix a prime $p\ge p_0$ with $p\equiv\mathfrak c\pmod4$, so that $r\le r_0$. \emph{Uniformity.} (S1) at $p_0$ gives (S1) at $p$. By \cref{lem:spectral-monotone} and the admissibility of the inputs, $\eps_V(r)\le\bar\eps_V<1$, $\eps_Z(r)\le\eps_Z(r_0)<1$, $\eta_Q(r)\le\bar\eta_Q$, $\eta_B(r)\le\bar\eta_B$, $c_\perp(r)\le\cperp$, and $\eps_\varrho/r$ is nondecreasing; the matrices depend only on $\mathfrak c$. So \cref{cor:spec2:coupling} and \cref{prop:spec2:mucentre} apply at $p$. Let $\Xi_\pm$ be the set of $\xi\ne0$ with $\chi(\xi)\eps_G=\pm1$ if $\mathfrak c=1$, and with $\chi(\xi)\eps_G=\pm i$ if $\mathfrak c=3$; the two sets partition $\Fp^\times$, and $\Azero(\xi)=\mathbf A_{\mathfrak c,\pm}$ on $\Xi_\pm$ (\cref{lem:spec:gauss}). For $s>0$ write $\mathbf M_{\mathfrak c,\pm}(s)$ for the matrix of \eqref{eq:spectral-test} with $s$ in place of $\tau^{\rm sp}_{\mathfrak c,\pm}$. For every $s>0$ and every $\xi\in\Xi_\pm$, the matrix \[ \mathcal M_s(\xi)=\Azero(\xi)-\frac{\Hmat^+-\Azero(\xi)^*\Azero(\xi)}s -\Big(\eta_Q(r)+\frac{\eta_B(r)}s\Big)I \] dominates $\mathbf M_{\mathfrak c,\pm}(s)-(\cperp+s)I$ (\cref{lem:majorant}(d)), so $\mathcal M_s(\xi)\succeq-(\cperp+s)I$ whenever $\mathbf M_{\mathfrak c,\pm}(s)\succeq0$, in particular for $s=\tau^{\rm sp}_{\mathfrak c,\pm}$. \emph{Centring at the half-law mean.} Let $F$ be real, with the decomposition $F=c+F_V+F_\perp$ of \cref{prop:spec2:mucentre}. By parts \ref{it:centre:form} and \ref{it:centre:cperp} of that proposition, \[ Q(F)\ge-\cperp r\norm{F_\perp}^2+Q(F_V)+2\ip{F_\perp}{\Op F_V}, \] and $Q(F_V)\ge r\sum_{\xi\ne0}\hat g(\xi)^*(\Azero(\xi)-\eta_QI)\hat g(\xi)$ (\cref{lem:spec:degone}(a),(b)). \emph{Splitting by translation characters.} Work in the complexification of $L^2(\mu)$ and let $F_{V,\pm}$ and $F_{\perp,\pm}$ be the components of $F_V$ and $F_\perp$ in $\bigoplus_{\xi\in\Xi_\pm}\mathcal W_\xi$. These summands are orthogonal for either prime class. The components need not be real: $F_{V,\pm}\in\mathcal V$ has coefficients $\hat g\one_{\Xi_\pm}$, $F_{\perp,\pm}\perp\mathcal V$, and $\norm{F_{\perp,+}}^2+\norm{F_{\perp,-}}^2\le\norm{F_\perp}^2$. As $\Op$ and $\Pi_{\mathcal V}$ preserve every translation sector, \[ \ip{F_\perp}{\Op F_V} =\sum_\pm\ip{F_{\perp,\pm}}{(I-\Pi_{\mathcal V})\Op F_{V,\pm}}. \] Put $s_\pm=\tau^{\rm sp}_{\mathfrak c,\pm}$. Young's inequality on each orthogonal summand and the complex form of \eqref{eq:spec:coupling} give \[ 2|\ip{F_\perp}{\Op F_V}|\le\sum_\pm\Big(s_\pm r\norm{F_{\perp,\pm}}^2 +\frac r{s_\pm}\sum_{\xi\in\Xi_\pm}\hat g^*\big(\Hmat^+-\Azero^*\Azero+\eta_BI\big)\hat g\Big). \] Hence $Q(F)\ge r\sum_\pm\sum_{\xi\in\Xi_\pm}\hat g^*\mathcal M_{s_\pm}(\xi)\hat g-\cperp r\norm{F_\perp}^2 -\sum_\pm s_\pm r\norm{F_{\perp,\pm}}^2$, and by the uniformity step \[ Q(F)\ge-\big(\cperp+\max_\pm s_\pm\big)r\big(\norm g^2+\norm{F_\perp}^2\big) \ge-g_{\mathfrak c}(1-\bar\eps_V)\,r\,(c^2+\norm g^2+\norm{F_\perp}^2) \ge-g_{\mathfrak c}r\norm F^2, \] by \cref{prop:spec2:mucentre}\ref{it:centre:decomp}. This proves (a) for both classes. The difference between the classes remains entirely in their finite matrices: for class three the two tests with a common parameter are complex conjugate, as stated in the theorem. \emph{The compression (b).} For real $h\perp\one$, $c=0$ in the decomposition, and \cref{prop:spec2:mucentre}\ref{it:centre:perp} is two-sided: $-Q(h_\perp)\ge-R_Z(N_{\rm ns}+D_{\rm col})\norm{h_\perp}^2\ge-\cperp r\norm{h_\perp}^2$. Apply the argument above to $-\Op$: only the sign of $\Azero(\xi)$ changes, and on the modes $\Xi_\pm$ the bracket of $-\Op$ is $\mathcal M_s$ with $\mathbf A_{\mathfrak c,\mp}$; use $s=\tau^{\rm sp}_{\mathfrak c,\mp}$ on those modes. This gives $-Q(h)\ge-g_{\mathfrak c}r\norm h^2$, and with (a) $|Q(h)|\le g_{\mathfrak c}r\norm h^2$; as $P_0\Op P_0$ is real symmetric, (b) follows. This is why both signs are needed: on a given mode the lower bound uses one sign and the upper bound the other. \emph{(c) and (d).} (c) is \cref{prop:spec2:mucentre}\ref{it:centre:rho} together with $p\eps_\varrho(r)^2=(\eps_\varrho(r)/r)^2\le(\eps_\varrho(r_0)/r_0)^2$. (d) is \cref{prop:matching:positive}(c) with $e=\eps_\varrho$ and $\beta=gr\ge g_{\mathfrak c}r$, using (b) and (c). \end{proof} \begin{remark}[Pinned correlations of the half law are not used]\label{rem:spectral-criterion:influence} The proof uses \textup{(S1)} only, through the extension counts of the degree-one and coupling blocks (\cref{lem:spec:small,lem:spec2:gram,lem:spec2:paley}), the star means, the nonstar extraction (\cref{lem:matching:extractionk}), the coincidence bound and the normalization. After $\mu$-centring the empty set and the stars vanish on $F_\perp$, and every other character set, each $K_{2,2}$ included, is a leaf of the nonstar partition. The influence conditions \eqref{eq:spec:S2} of $G^+$ were needed in the perpendicular estimates of those earlier 216-slot criteria that charged the $K_{2,2}$ terms separately through a pure-pair frame bound $\sum_J\norm{\Pi_{H_J}F}^2\le\mathrm{Fr}\,\norm F^2$ (\cref{subsec:obs:tested}); the criterion here does not use that bound, although the certificates still assert \eqref{eq:spec:S2} for $G^+$ (\cref{rem:spectral-criterion:certificate}). \end{remark} \begin{remark}[The row-norm criterion]\label{rem:spectral-criterion:row} If $s>0$ satisfies $s^2-(\Lambda_D+\bar\eta_Q)s-(\bar\lambda(\Hmat^+)+\bar\eta_B)\ge0$, then \eqref{eq:spectral-test} holds with $\tau^{\rm sp}_{\mathfrak c,\pm}=s$, because $\mathbf A_{\mathfrak c,\pm}\succeq-\Lambda_DI$ and $\Hmat^+-(\Delta^E)^{\mathsf T}\Delta^E\preceq\bar\lambda(\Hmat^+)I$. A scalar test of this kind, with row norms and the earlier model $2\Hmat$, was the acceptance test of an earlier version of the criterion. No certificate of the final construction uses it: every cap is certified by the matrix test \eqref{eq:spectral-test} itself. \end{remark} \begin{remark}[The earlier criteria]\label{rem:spectral-criterion:history} The criteria of the 216-slot design (its Theorem~S and its sharpenings at its middle cuts; see \cref{sec:history}) are built from the same blocks, those of \cref{subsec:spec:fourier,subsec:spec:degone,subsec:spec:coupling,subsec:spec:perp}, and the same Schur complement. Theorem~S centres at $\E_{m_p}F$, uses the model $2\Hmat$ and bounds the perpendicular block by decision trees and bicliques. Its sharpenings centre at $\E_\mu F$ as in \cref{prop:spec2:mucentre} and treat the class-one Paley terms with dilation parity and an exceptional-clique term (here $\Hmat^{\rm cov}$ and $\bar\zeta$ suffice, \cref{subsec:advance:parity}); they charge the $K_{2,2}$ terms first through a pure-pair frame and finally, in the matching test, through a matching partition and coincidence charging as in \cref{subsec:spec:centring}. All of them use one test parameter for all signs and assume \eqref{eq:spec:S2}. So they are not literally cases of \cref{thm:spectral-criterion}, and no cap of the final construction uses them; \cref{subsec:history:216} records them. \end{remark} \begin{remark}[Where route A is applied]\label{rem:spectral-criterion:uses} The three applications evaluate the same test and differ only in the inputs. \begin{enumerate}[label=\textup{(\roman*)}] \item \emph{Twelve-label middle cuts} (\cref{lem:layer12-caps}): the cuts L21, E21 and L10 of the uniform graph laws. The cuts F21 and L20 are computed as well, but the middle uses for F21 the negative cap $k_{\rm D}$ of the reference fold record (\cref{lem:old-f-law}, \cref{cert:record:old-f-cap}) and for L20 the caps of \cref{subsec:middle-l20}, from the complete actual stars; on the three late middle pieces the two-layer root is a positive reweighting of the uniform root (the tilted law of \cref{sec:positive-roots}), and its cuts L20 and L21 have the caps of \cref{prop:root-chamber,prop:root-layer}. The two grids of \cref{cert:layer12-grid} have $26$ and $9$ thresholds and $520$ and $180$ exact tests. $N_{\rm ns}$ from a compressed matching partition, $D_{\rm col}=D_{\rm nat}$ of \eqref{eq:collision-natural}, the standard star inputs ($M_\star=W_{\rm st}$, $Z_\star=2(P_{\rm st}+W_{\rm st})$), and the standard coupling inputs ($\eps_H=\eps'_H+\eps_X$, $\Gamma_E=\hat E^2$, $\bar\zeta=\zeta$). The block caps use $g_3$ only; $B^+$ is computed with the maximum over both classes, which is allowed by (d). \item \emph{Ten nonroot upper cuts} (\ref{it:record:upper-F6}): FL21, EL21, FL22, EL22, FF22, FE22, EE22, LL10, FL11, EL11, at the thresholds $2^{47}$ (for the upper bands below $2^{48}$) and $2^{48}$ (for the bands from $2^{48}$ on) and at the thresholds of the tail datum; inputs as in (i). Below $\Pfour=2^{512}$ only class three occurs, and $g$ is the larger of the caps of the two conjugate class-three tests; for the tail datum $g$ is the maximum over both classes and both signs. The merge and constant marginals of EL22 in four reserved states have the observed caps of \cref{prop:observed-caps}, which are not route-A applications. \item \emph{Completed roots} LL20, LL22 from $2^{52}$ on (\cref{lem:upper-completed-root}): $N_{\rm ns}=\sum_{k=2}^4C_kr^k$ from the augmented partition (a refinement of the compressed partition of \cref{lem:advance:compressed-partition}), with the nonstar coefficients $C_k$ of \cref{cor:extraction-leaf}(b); $D_{\rm col}=\min(D_{\rm ord},D_{\rm nat})$ (\cref{lem:oct24-collision}(e)); $M_\star$ and $Z_\star$ of \cref{prop:advance:ordered-star,lem:star-mean}, maximized over the two classes; $\eps_Z$ the smaller of $2(P_{\rm st}+W_{\rm st})+N_{\rm ns}+D_{\rm nat}$ and $Z_\star+N_{\rm ns}+D_{\rm col}$; $R_+$ recomputed with this $\eps_Z$; $\Gamma_E$ and $\eps_H$ the minima of \cref{subsec:spec:completion-variance}; and, at class one, $\bar\zeta$ the minimum of \cref{lem:spec2:parity-transfer}. \end{enumerate} \end{remark} \subsection{Route~B (uniform averages over allowed sets)}\label{subsec:spec:routeB} Route~A tests the cut operator through the conditional law of the opposite half, whose completion counts it must control. At the two root cuts this needs the completion-variance denominator $\ell^{\rm loc}_k$ of \cref{lem:push:localvariance} to be positive, which holds only for $p$ above approximately $2^{49.96}$ for $\mathrm{LL20}$ and $2^{49.30}$ for $\mathrm{LL22}$ --- well above $\Pthree$, which is why Route~B is used at these cuts; no bound in the paper uses these approximate values as thresholds. Route~B expands the kernel around the product of the half laws and compares its star part with explicit normalized stars: averages over the allowed sets $\Phi_k(x)$, not conditional laws of the completed cut law. Their star synthesis is controlled by a finite Schur test. It is stated for $p\equiv3\pmod4$, the only class at which it is applied. \paragraph{Setting.} Let $p\equiv3\pmod4$ be a prime with $e_\Delta(p,2n)<1$ and $p>4n^2$. Then $\Hmat^+=\Hmat$, $\Azero(\xi)=\chi(\xi)\eps_G\Delta^E=\pm i\Delta^E$ is Hermitian, $\Azero(\xi)^2=(\Delta^E)^{\mathsf T}\Delta^E$, and both signs occur. Let $\Lambda_D\ge\norm{\Delta^E}$ and $\mathbf R=\Hmat-(\Delta^E)^{\mathsf T}\Delta^E$. Let $U=L^2_0(\Fp)$ and $\mathbf E\colon U^n\to L^2(\mu)$, $(\mathbf Eg)(x)=\sum_kg_k(x_k)$; the \emph{explicit star} is $(B_kg)(x)=|\Phi_k(x)|^{-1}\sum_{t\in\Phi_k(x)}g(t)$, with $\mathbf Bg=\sum_kB_kg_k$. Put $(S_kg)(x)=\E_t\varphi_k(t;x)g(t)$ and $\mathbf Sg=\sum_kS_kg_k$. Translations act unitarily on $U^n$ and diagonally on $L^2(\mu)$, and $\mathbf E$, $\mathbf B$, $\mathbf S$ intertwine these actions ($\Phi_k(x+c\one)=\Phi_k(x)+c$). Hence $\mathbf E^*\mathbf E$, $\mathbf E^*\mathbf B$ and $\mathbf B^*\mathbf B$ preserve each mode $\C^ne_\xi$, $\xi\ne0$, and act there by $n\times n$ matrices; distinct modes have orthogonal images. \begin{theorem}[Spectral criterion from uniform averages over allowed sets (Route~B)]\label{thm:record:direct-star} In this setting assume the following. \begin{enumerate}[label=\textup{(H\arabic*)}] \item\label{it:record:star-H1} \emph{Frame.} On every mode $\xi\ne0$, \[ \norm{\mathbf E^*\mathbf E-I}\le\eps_V,\qquad \norm{\mathbf E^*\mathbf B/r-\Azero(\xi)}\le\eps_\times,\qquad \mathbf B^*\mathbf B/r^2\preceq\Hmat+\eps_{\mathbf B}I . \] \item\label{it:record:star-H2} \emph{Schur test.} With $\eps_{\mathbf W}=\eps_{\mathbf B}+2\Lambda_D\eps_\times+\Lambda_D^2\eps_V$ and $\eps_{\mathbf{EW}}=\eps_\times+\Lambda_D\eps_V$, there are rationals $s_\star,g_\star>0$ such that, with $\alpha_\star=1+\eps_V+s_\star$ and $\beta_\star=\eps_{\mathbf W}+\eps_{\mathbf{EW}}^2/s_\star$, the matrix $\mathbf R+\beta_\star I$ is positive definite and \begin{equation}\label{eq:record:schur} \pm\eps_G\Delta^E+\frac{g_\star}{\alpha_\star}I-\frac{\mathbf R+\beta_\star I}{g_\star}\succeq0 \qquad\text{for both signs}. \end{equation} \item\label{it:record:star-H3} \emph{Inputs.} Nonnegative numbers $N_{\rm ns}$, $D_{\rm col}$, $M_\star$, $z_\star$ and $Z_\star$ satisfy $\norm{T_{\rm ns}}\le N_{\rm ns}$, $\norm{T_{\rm coll}}\le D_{\rm col}$, $\norm{h_\star-\E_\mu h_\star}_\mu\le M_\star$, $|\E_\mu h_\star|\le z_\star$ and $2|\E_\mu h_\star|\le Z_\star$, and $\eps_Z:=Z_\star+N_{\rm ns}+D_{\rm col}<1$. \end{enumerate} Put \begin{gather*} \eps_{\rm soft}=2(1+\eps_V)^{1/2}\Big[r\Big(\sum_k\hat e_k^2(\Hmat_{kk}+\eps_{\mathbf B})\Big)^{1/2} +nr^2\Big(\sum_k4^{r_k}\Big)^{1/2}\Big],\\ g_{\rm root}=\frac{g_\star+(N_{\rm ns}+D_{\rm col}+M_\star^2+z_\star^2+\eps_{\rm soft})/r}{1-\eps_Z}, \qquad \eps_\varrho=\frac{M_\star+N_{\rm ns}+D_{\rm col}}{1-\eps_Z}. \end{gather*} Then, with $\mathbf W=\mathbf B/r-\mathbf E\Azero$ and $\mathbf L=r(\mathbf E\Azero\mathbf E^*+\mathbf E\mathbf W^*+\mathbf W\mathbf E^*)$: \begin{enumerate}[label=\textup{(\alph*)}] \item $-g_\star rI\preceq\mathbf L\preceq g_\star rI$; \item $K_0=(\one+h_\star)\otimes(\one+h_\star)+\mathbf L+\mathcal R$ with $\norm{\mathcal R}\le N_{\rm ns}+D_{\rm col}+M_\star^2+z_\star^2+\eps_{\rm soft}$; \item $|Z_0-1|\le\eps_Z$ and $\Op\succeq-g_{\rm root}rI$; \item $\norm{P_0\Op\one}\le\eps_\varrho$ and $\norm{P_0\Op P_0}\le g_{\rm root}r$; \item if $g_{\rm root}r<1$, then $\Op\preceq(1+B_{\rm top}/p)I$ with $B_{\rm top}=p\eps_\varrho^2/(1-g_{\rm root}r)$. \end{enumerate} \end{theorem} The two signs in \eqref{eq:record:schur} are the two values of $\Azero(\xi)$. Each direction of (a) needs both: on a given mode the lower bound uses the sign $\chi(\xi)$, and the upper bound the opposite one. The upper bound in (a) enters through (d), and (d) enters (e). The two matrices of \eqref{eq:record:schur} are complex conjugates ($\eps_G\Delta^E$ is $\pm i$ times a real matrix and $\mathbf R$ is real), so either test implies the other; the certificate checks both. \begin{proof} (a) Let $\mathbf F=[\mathbf E,\mathbf W]\colon U^n\oplus U^n\to L^2(\mu)$ and, on the mode $\xi$, $\mathcal C(\xi)=\begin{psmallmatrix}\Azero(\xi)&I\\ I&0\end{psmallmatrix}$. Then $\mathbf F\mathcal C\mathbf F^*=\mathbf E\Azero\mathbf E^*+\mathbf W\mathbf E^*+\mathbf E\mathbf W^*=\mathbf L/r$. Write $\Gamma=\mathbf E^*\mathbf B/r-\Azero$ and $\Delta_V=\mathbf E^*\mathbf E-I$, so $\norm\Gamma\le\eps_\times$ and $\norm{\Delta_V}\le\eps_V$. Then $\mathbf E^*\mathbf W=\Gamma-\Delta_V\Azero$ has norm at most $\eps_{\mathbf{EW}}$, and \[ \mathbf W^*\mathbf W=\frac{\mathbf B^*\mathbf B}{r^2}-\Azero^2-\Gamma^*\Azero-\Azero\Gamma+\Azero\Delta_V\Azero \preceq\mathbf R+\eps_{\mathbf W}I . \] For $(u,v)$ on one mode, $\norm{\mathbf Eu+\mathbf Wv}^2\le(1+\eps_V)\norm u^2+2\eps_{\mathbf{EW}}\norm u\norm v +\ip v{(\mathbf R+\eps_{\mathbf W})v}$, and $2\eps_{\mathbf{EW}}\norm u\norm v\le s_\star\norm u^2+\eps_{\mathbf{EW}}^2\norm v^2/s_\star$ gives $\mathbf F^*\mathbf F\preceq\mathcal M:=\diag(\alpha_\star I,\mathbf R+\beta_\star I)$, which is positive definite. Thus $\mathcal Q=\mathbf F\mathcal M^{-1/2}$ has norm at most one, and $\mathbf F\mathcal C\mathbf F^*=\mathcal Q(\mathcal M^{1/2}\mathcal C\mathcal M^{1/2})\mathcal Q^*$. By congruence, $\mathcal M^{1/2}\mathcal C\mathcal M^{1/2}+g_\star I\succeq0$ is equivalent to $\mathcal C+g_\star\mathcal M^{-1}\succeq0$, that is, to \[ \begin{pmatrix}\Azero(\xi)+(g_\star/\alpha_\star)I&I\\ I&g_\star(\mathbf R+\beta_\star I)^{-1}\end{pmatrix}\succeq0, \] and, the lower right block being positive definite, to the Schur complement condition \eqref{eq:record:schur} with the sign of $\chi(\xi)$. Hence $\mathbf L\succeq-\mathcal Q(g_\star rI)\mathcal Q^*\succeq-g_\star rI$. For the upper bound conjugate by the unitary $\diag(I,-I)$, which commutes with $\mathcal M$: it carries $-\mathcal C(\xi)$ to the matrix $\mathcal C$ with $-\Azero(\xi)$ in place of $\Azero(\xi)$, and the same argument with the other sign of \eqref{eq:record:schur} gives $-\mathbf L\succeq-g_\star rI$. (b) \emph{Stars.} The uniform one-vertex marginals of $\mu$ give $(\mathbf E^*f)_k(t)=\E_\mu[f\mid x_k=t]-\E_\mu f$. By \cref{lem:spec:stars}(a), summed over $\emptyset\ne J\subseteq N(k)$, the column stars at $k$ act by \[ f\mapsto\E_t\big[(\varphi_k(t;x)-1)\big(\E_\mu f+(\mathbf E^*f)_k(t)\big)\big] =h_{\star,k}(x)\,\E_\mu f+\big(S_k(\mathbf E^*f)_k\big)(x), \] since $\E_t(\mathbf E^*f)_k=0$. So the column stars give $h_\star\otimes\one+\mathbf S\mathbf E^*$, and the row stars, their adjoints by \cref{lem:spec:stars}(b), give $\one\otimes h_\star+\mathbf E\mathbf S^*$. Row and column stars overlap exactly in the single pairs. The single pair $\{(j,k)\}$ acts by $f\mapsto\chi(\varsigma_{jk})(C(\mathbf E^*f)_k)(x_j)$, since its constant part integrates to zero; as $Ce_\xi=r\chi(\xi)\eps_Ge_\xi$, the single pairs sum to $r\mathbf E\Azero\mathbf E^*$. By \eqref{eq:record:root-kernel}, \[ K_0=(\one+h_\star)\otimes(\one+h_\star)-h_\star\otimes h_\star+\mathbf S\mathbf E^*+\mathbf E\mathbf S^* -r\mathbf E\Azero\mathbf E^*+T_{\rm ns}-T_{\rm coll}. \] Since $\mathbf B=r(\mathbf E\Azero+\mathbf W)$ and $\Azero$ is Hermitian, $\mathbf B\mathbf E^*+\mathbf E\mathbf B^*-r\mathbf E\Azero\mathbf E^*=\mathbf L$. Hence (b) holds with $\mathcal R=(\mathbf S-\mathbf B)\mathbf E^*+\mathbf E(\mathbf S-\mathbf B)^*-h_\star\otimes h_\star+T_{\rm ns}-T_{\rm coll}$, and $\norm{h_\star\otimes h_\star}=\norm{h_\star}^2_\mu=\norm{h_\star-\E_\mu h_\star}^2+(\E_\mu h_\star)^2\le M_\star^2+z_\star^2$. \emph{Soft stars.} For $t\notin x(U^+)$ each factor of $\varphi_k(t;x)$ is $0$ or $2$, so $\varphi_k(t;x)=2^{r_k}\one_{\Phi_k(x)}(t)$. Hence \[ S_kg=a_k\,B_kg+\mathrm{coll}_kg,\qquad a_k(x)=\frac{2^{r_k}|\Phi_k(x)|}p,\qquad (\mathrm{coll}_kg)(x)=\frac1p\sum_{i\in U^+}\varphi_k(x_i;x)g(x_i), \] with $|a_k-1|\le\hat e_k$ and $0\le\varphi_k\le2^{r_k}$. By \ref{it:record:star-H1} on the modes, $\norm{B_kg}\le r(\Hmat_{kk}+\eps_{\mathbf B})^{1/2}\norm g$, and each $x_i$ is uniform, so $\norm{\mathrm{coll}_kg}\le n2^{r_k}p^{-1}\norm g$. Cauchy--Schwarz over $k$ gives \[ \norm{\mathbf S-\mathbf B}\le r\Big(\sum_k\hat e_k^2(\Hmat_{kk}+\eps_{\mathbf B})\Big)^{1/2} +\frac np\Big(\sum_k4^{r_k}\Big)^{1/2}, \] and $\norm{\mathbf E}\le(1+\eps_V)^{1/2}$, so the two soft terms of $\mathcal R$ have norm at most $\eps_{\rm soft}$. (c) The images of $\mathbf E$, $\mathbf B$ and $\mathbf S$ have $\mu$-mean zero: the first because the one-vertex marginals are uniform, the others because the law of $t$ in $B_k$, and the weight $\E_\mu\varphi_k(t;x)$ in $S_k$, are translation invariant in $t$. Also $\mathbf E^*\one=0$. Hence $\mathbf L\one=0$, $\ip\one{\mathbf L\,\cdot}=0$ and $(\mathbf S-\mathbf B)^*\one=0$. Pairing (b) with $\one$, $Z_0=\ip\one{K_0\one}=1+2\E_\mu h_\star+\ip\one{(T_{\rm ns}-T_{\rm coll})\one}$, so $|Z_0-1|\le\eps_Z$; moreover $Z_0>0$. As $(\one+h_\star)\otimes(\one+h_\star)\succeq0$, (a) and (b) give $K_0\succeq-(g_\star r+\norm{\mathcal R})I$, and dividing by $Z_0\ge1-\eps_Z$ gives $\Op\succeq-g_{\rm root}rI$. (d) Applying (b) to $\one$ and projecting, $P_0K_0\one=(h_\star-\E_\mu h_\star)+P_0(T_{\rm ns}-T_{\rm coll})\one$, because the soft terms vanish on $\one$ and the term $-h_\star\E_\mu h_\star$ of $\mathcal R$ cancels against $(\one+h_\star)\E_\mu h_\star$. Hence $\norm{P_0K_0\one}\le M_\star+N_{\rm ns}+D_{\rm col}$. Compressing (b) by $P_0$ on both sides removes $\one\otimes\one$, $h_\star\otimes\one$ and $\one\otimes h_\star$; the two terms $\pm P_0(h_\star\otimes h_\star)P_0$ cancel, and $P_0\mathbf LP_0=\mathbf L$. Thus $P_0K_0P_0=\mathbf L+P_0[(\mathbf S-\mathbf B)\mathbf E^*+\mathbf E(\mathbf S-\mathbf B)^*+T_{\rm ns}-T_{\rm coll}]P_0$, of norm at most $g_\star r+\eps_{\rm soft}+N_{\rm ns}+D_{\rm col}$ by (a). Divide by $Z_0$. (e) $\Op$ is self-adjoint with $\ip\one{\Op\one}=1$; use \cref{prop:matching:positive}(a) with $e=\eps_\varrho$ and $\beta=g_{\rm root}r$, by (d). \end{proof} The proof never uses the completed conditional law of the root, its row ratio $\Rcut$, or the completion-variance denominator. The rank-one term $h_\star\otimes h_\star$ is included in the remainder bound of \textup{(b)} through $M_\star^2+z_\star^2$, not omitted, and it does not enter the centred block. \begin{lemma}[Inputs for the star synthesis at the root cuts]\label{lem:record:frame-inputs} In the setting of \cref{thm:record:direct-star}, \ref{it:record:star-H1} holds with the following numbers, in which $\hat E^2$, $\eps_{\rm rem}$ and $\eps_{\ne}$ are the quantities so named in \cref{subsec:spec:coupling}, specialised to the explicit-stars mode ($R'_k=1$ and $R_\nu=1$, so that $\Delta_k=\hat e_k/(1-\hat e_k)$ and $\theta^\mu_j$ has no $R_\nu$ factor). \begin{enumerate}[label=\textup{(\roman*)}] \item $\eps_V$ is the quantity \eqref{eq:spec:epsV}. \item With $\phi_k=(\hat e_k+e_{r_k+1}(p,n))/(1-\hat e_k)$, \[ \eps_\times=\frac n{(p-1)r}+\frac{\Lambda_D}{p-1}+\frac p{p-1} \Big(\max_i\sum_{k:\,\varsigma_{ik}=0}\phi_k\cdot\max_k\sum_{i:\,\varsigma_{ik}=0}\phi_k\Big)^{1/2}. \] \item With $\eps'_H$ of \eqref{eq:spec:beta}, $\theta^\mu_j=(2^{d^0_j}/(1-e_{d^0_j}(p,n))-1)^{1/2}$, $\rho_{\rm row}$ as in \cref{subsec:spec:coupling}, and \begin{gather*} \hat E^2=\sum_k\Big(2^{r_k}(1+\hat e_k)\Big(\frac{\hat e_k}{1-\hat e_k}\Big)^2+\frac{n4^{r_k}}p\Big), \qquad \eps_{\rm rem}=2\big(\hat E^2(\norm\Hmat_{\rm row}+\eps'_H)\big)^{1/2}+\hat E^2,\\ \eps_{\ne}=r\max_j\theta^\mu_j\,\rho_{\rm row},\qquad \eps_{\mathbf B}=\Big(\frac p{p-1}-1\Big)\norm\Hmat_{\rm row}+\frac p{p-1}\big(\eps'_H+\eps_{\ne}+\eps_{\rm rem}\big). \end{gather*} \end{enumerate} \end{lemma} \begin{proof} (i) On the mode $\xi$, $\mathbf E^*\mathbf E$ is the matrix $\mathbf N(\xi)$ of \cref{lem:spec:degone}(c). (ii) The pair $(x_i,t)$, with $x\sim\mu$ and $t$ uniform on $\Phi_k(x)$, has an $\mathrm{Aff}_p$-invariant law, and $t\ne x_i$ always. By \cref{lem:spec:affpair}(b) the entry $(i,k)$ of $\mathbf E^*\mathbf B$ on the mode $\xi$ is $-1/(p-1)+\frac p{p-1}m_{ik}c_\xi$, where $m_{ik}=\E\chi(t-x_i)$. If $\varsigma_{ik}\ne0$, every $t\in\Phi_k(x)$ satisfies $\chi(t-x_i)=\chi(\varsigma_{ik})$, so $m_{ik}=\Delta^E_{ik}$. If $\varsigma_{ik}=0$ (including $i=k$), $x_i$ is not a root of the constraints of $\Phi_k(x)$, and the $t\in\Phi_k(x)$ with $\chi(t-x_i)=1$ are cut out by $r_k+1$ constraints with distinct roots; their number lies in $p2^{-r_k-1}[1\pm e_{r_k+1}(p,n)]$. Since $\sum_{t\in\Phi_k}\chi(t-x_i)=2\#\{\chi=1\}-|\Phi_k|$, this sum is at most $p2^{-r_k}(e_{r_k+1}+\hat e_k)$ in modulus, and $|m_{ik}|\le\phi_k$ pointwise in $x$. Therefore \[ \frac{\mathbf E^*\mathbf B}r-\Azero(\xi)=-\frac{\one\one^{\mathsf T}}{(p-1)r}+\frac{\Azero(\xi)}{p-1} +\frac p{p-1}\chi(\xi)\eps_GM^{\rm off}, \] where $M^{\rm off}$ has the entries $m_{ik}$ with $\varsigma_{ik}=0$ and zeros elsewhere. Bound the three norms by $n$, $\Lambda_D$ and the Schur test. (iii) This is \cref{subsec:spec:coupling} for the explicit stars, instance (B), in which $R_\nu=1$ and $R'_k=1$: then $\theta_j=\theta^\mu_j$, $\Delta_k=\hat e_k/(1-\hat e_k)$ and $\eps_X=0$. For $w\in\C^n$, $\mathbf B(we_\xi)=\mathcal P(\sum_kw_ke_\xi(x_k))$ in the notation of \cref{def:coupling-data}, so by \cref{lem:coupling-modes} \[ \frac{w^*(\mathbf B^*\mathbf B)(\xi)w}{r^2}=\frac{w^*\mathbf M(\xi)w}{r^2} =\frac p{p-1}\big(w^*\Hmat^0w+pc_\xi\,w^*\mathbf D^0w\big), \] with $\Hmat^0=\widetilde\Hmat$ and $\mathbf D^0=\mathbf D$ for these data. By \cref{lem:spec2:gram}, $\Hmat^0\preceq\Hmat+\eps'_HI$; by \cref{lem:spec2:paley}, with $\Gamma_E=\hat E^2$, $\bar\lambda(\Hmat)=\norm\Hmat_{\rm row}$ and $\eps_H=\eps'_H$, and since $t_J=0$ for $p\equiv3\pmod4$, $|w^*\mathbf D^0w|\le r(\eps_{\ne}+\eps_{\rm rem})|w|^2$. As $|pc_\xi|r=1$ and $\Hmat\succeq0$, $\norm\Hmat\le\norm\Hmat_{\rm row}$, \[ \frac{w^*\mathbf B^*\mathbf Bw}{r^2}\le\frac p{p-1}\big(w^*\Hmat w+(\eps'_H+\eps_{\ne}+\eps_{\rm rem})|w|^2\big) \le w^*\Hmat w+\eps_{\mathbf B}|w|^2. \qedhere \] \end{proof} The same proofs give \cref{thm:record:direct-star} and \cref{lem:record:frame-inputs} at $p\equiv1\pmod4$, with $\Hmat^+=\Hmat+\Hmat^{\rm cov}$ in place of $\Hmat$ everywhere except inside $\eps_{\rm rem}$, with $\pm\Delta^E$ in place of $\pm\eps_G\Delta^E$ (now two distinct tests), and with $\eps_{\rm par}=(R_{\rm full}-1+n/((p-n)r))\norm{\Hmat^{\rm nc}}_{\rm row}$ ($R_{\rm full}$ is defined in \cref{lem:spec2:paley-one} below) added inside the last bracket of $\eps_{\mathbf B}$ (\cref{lem:spec2:paley-one} with $R_\nu=1$); the caps of the final construction use only $p\equiv3\pmod4$. The application to the root cuts, with the inputs of \ref{it:record:star-H3}, the monotone extension from an endpoint, the exact frame and Schur tests and the certified class-three caps, is \cref{lem:record:direct-star-inputs}, \cref{lem:record:monotone-endpoint}, \cref{cert:record:direct-star} and \cref{cert:upper-root-caps}. \subsection{From one prime to all primes and blocks}\label{subsec:spec:thresholds} Both criteria are checked at one threshold and used at every larger prime and on blocks of primes. The first step is the monotonicity of the error terms. \begin{lemma}[Monotone spectral quantities]\label{lem:spectral-monotone} Let spectral data satisfy \textup{(S1)} at $p_0$, $r_0=p_0^{-1/2}$, and write every quantity as a function of $r\in(0,r_0]$. In part~\textup{(a)}, quantities involving coupling data use instance~\textup{(A)} or~\textup{(B)} of \cref{subsec:spec:coupling}. \begin{enumerate}[label=\textup{(\alph*)}] \item The following are admissible: every $e_t(p,n')$ with $t\le\Delta$, $n'\le2n$, and $\hat e_k$; $\Rcut-1$, $R_{\rm full}-1$, $R'_k-1$, $R_\nu R_{\rm full}-1$ and their quotients by $r$; $\delta^\times_l$, $\delta^\mu_l$, $\eps_V$ and $\eta_Q$; $\beta_{kl}$, $\eps'_H$, $\Upsilon_{kl}$ and $\eps_X$; $\theta_j$, $\theta^\mu_j$, $\eps_{\ne}$, $\Delta_k$, $\hat E^2$, $\phi_k$, $\eps_\times$, and $\zeta$ of \cref{lem:spec2:paley-one}. \item If the inputs $\Gamma_E$, $\eps_H$, $\bar\zeta$ and $R_+$ are admissible, so are $\eps_{\rm rem}$, $\eps_{\rm par}$, $\eta_B$ and $\Lambda_M$. \item If $N_{\rm ns}/r$, $D_{\rm col}/r$, $M_\star/r$ and $\eps_Z$ are admissible and $\eps_Z(r_0)<1$, then $R_Z$, $R_+$ of \cref{prop:spec2:mucentre}\ref{it:centre:sup}, $\eps_\varrho/r$, $\eps_\varrho$ and $c_\perp$ are admissible, and so are the bound $R_{\rm full}-1+n/((p-n)r)+\eps_\varrho$ of \cref{lem:spec2:parity-transfer} and its minimum with $\zeta$; $P_{\rm st}/r^2$ and $W_{\rm st}/r$ are constants. \item If the count errors $\epsilon^\pm_t$ of \cref{subsec:spec:completion-variance} are polynomials in $r$ with nonnegative coefficients, and at $r_0$ the denominators of \cref{lem:push:localvariance}\textup{(b)} are positive and $\ell^{\rm loc}_k>0$, then $\ell^{\rm loc}_k>0$ on $(0,r_0]$, and the bound $(\eps^{\rm loc}_k/\ell^{\rm loc}_k)^2$ of \cref{lem:push:localvariance}, the bound (a) there, $\Gamma^{\rm loc}_E$, and $\eps^{\rm loc}_H$ with fixed Schur weights are admissible. \end{enumerate} The matrices $\Delta^E$, $\Hmat$, $\Hmat^{\rm cov}$, $\Hmat^{\rm nc}$ and $\Hmat^+$ depend on $p$ only through its class modulo $4$. \end{lemma} \begin{proof} We use \cref{lem:majorant}. Every $e_t(p,n')=2^t(h_tr+n'r^2)$ is a polynomial in $r$ with nonnegative coefficients and no constant term; so is $e_u$ for every $u$; and by (S1) every $e_t(p,n')$ with $t\le\Delta$, $n'\le2n$ is below one at $r_0$, hence on $(0,r_0]$. Further $p/(p-1)=1/(1-r^2)$, $1/(p-1)=r^2/(1-r^2)$, $1/((p-1)r)=r/(1-r^2)$ and $n/((p-n)r)=nr/(1-nr^2)$, where $nr^2<1$ by (S1). A product of factors $(1+e)/(1-e)$ with small $e<1$ is one plus a small function. This gives the ratios and the constants of \eqref{eq:spec:smallconst}, \eqref{eq:spec:Azero}, \eqref{eq:spec:epsV}, $\Upsilon_{kl}$, $\eps_X$, $\hat E^2$ (whose last term is $n4^{r_k}r^2$), $\phi_k$, $\eps_\times$ and $\zeta=(R_\nu R_{\rm full}-1)+nr/(1-nr^2)$. In $\theta_j$ the argument of the square root is at least $0$ and nondecreasing, since $R_\nu\ge1$ and $2^{d^0_j}/(1-e)\ge1$, and $\eps_{\ne}=r\theta_{\max}\rho_{\rm row}$. Both branches of $\Delta_k$ are nondecreasing. In \eqref{eq:spec:beta} the second branch of the maximum never exceeds the first: for $0\le a,b<1$ and $e_u\ge0$, \[ \frac{1+e_u}{(1-a)(1-b)}+\frac{1-e_u}{(1+a)(1+b)}-2 =\frac{2\big(a^2+b^2+ab-a^2b^2+e_u(a+b)\big)}{(1-a^2)(1-b^2)}\ge0, \] so $\beta_{kl}$ equals its first branch, which is nondecreasing; this avoids any condition on $e_u$. For (b), $\eps_{\rm rem}$, $\eps_{\rm par}=\bar\zeta\Lambda_{\rm nc}$, $\Lambda_M$ and $\eta_B$ are built from these by sums, products and square roots, and $R_+p/(p-1)-1=R_+/(1-r^2)-1\ge0$ is nondecreasing. For (c), $R_Z=1/(1-\eps_Z)$ and $R_+$ are nondecreasing when $\eps_Z<1$ is; $\eps_\varrho/r=R_Z(M_\star/r+N_{\rm ns}/r+D_{\rm col}/r)$; $c_\perp=R_Z(N_{\rm ns}/r+D_{\rm col}/r)+r(\eps_\varrho/r)^2$; $\eps_\varrho=r\cdot(\eps_\varrho/r)$; and $R_{\rm full}-1$, $nr/(1-nr^2)$ and $\zeta$ are admissible by (a). For (d), the denominators $1-\epsilon^-_t(z)$ of $\kappa_\Phi$ and $\kappa_i$ are nonincreasing in $r$ and positive at $r_0$, so $\kappa_\Phi$ and $\kappa_i$ are admissible; every term of $\eps^{\rm loc}_k$ is built from $r$, $\kappa_\Phi$, $\kappa_i$, $\alpha^+_i$, $\alpha^{++}_i$ and fixed integers by sums, products and square roots, so it is admissible, while $\prod_i\alpha^-_i$ is nonincreasing; hence $\ell^{\rm loc}_k$ is nonincreasing and $\eps^{\rm loc}_k/\ell^{\rm loc}_k$ nondecreasing. The bound (a) is $\delta'^2_k/(4(1+\delta'_k))$ with $\delta'_k$ admissible, and $y\mapsto y^2/(4(1+y))$ increases. The remaining quantities are sums, products, minima and square roots of these, and a weighted Schur bound with fixed weights is a fixed nonnegative combination of matrix entries. \end{proof} \begin{remark}[How a cap is certified]\label{rem:spectral-criterion:certificate} For a cut and a threshold $p_0$ the route-A evaluator computes, at $r_0=p_0^{-1/2}$ and in outward interval arithmetic, the quantities of (R1)--(R3). It asserts $e_{d_l}(p_0,2n)<1$ for every $l$, hence the first half of (S1) (the second, $p_0>4n^2$, holds at every threshold used, since $p_0\ge2^{24}>4\cdot36^2\ge4n^2$ for the values $n\le36$ occurring in \cref{rem:spectral-criterion:uses}), $\eps_Z<\frac12$ and $\bar\eps_V<1$ (and asserts the influence conditions \eqref{eq:spec:S2} of $G^+$, which no statement uses). For each class $\mathfrak c\in\{1,3\}$ and each sign, a floating-point bisection proposes a rational $\tau^{\rm sp}_{\mathfrak c,\pm}$, which is accepted only by an exact rational $LDL^{\mathsf T}$ test of \eqref{eq:spectral-test}; for $\mathfrak c=3$ the test runs on the real $2n\times2n$ embedding of the Hermitian matrix (\cref{rem:realified-gates}). In this test $\cperp,\bar\eta_Q,\bar\eta_B,\bar\eps_V$ are the upper ends of the enclosures, rounded up to denominator $10^{10}$. The evaluator records $g_{\mathfrak c,\pm}=(\lceil10^8(\cperp+\tau^{\rm sp}_{\mathfrak c,\pm})/(1-\bar\eps_V)\rceil+1)/10^8$ and $g=\max_{\mathfrak c,\pm}g_{\mathfrak c,\pm}\ge\max(g_1,g_3)$, asserts $gr_0<1$, and records $B^+=p_0\eps_\varrho(r_0)^2/(1-gr_0)$ as an interval. An argument applying \cref{cor:spectral-criterion-blocks} at a block start $Q\ge p_0$ with block length at most $L$ uses $d=g'\exp(B^+L/(Q\log Q))$ and asserts $d/\sqrt Q<1$, where $g'=g_3$ in the middle range and on the bands of the upper range, where $B^+$ is also recomputed with $g_3$ in place of $g$, as (d) allows, and $g'=g$ for the tail datum (\cref{cor:spectral-criterion-blocks}). Every input is an admissible function fixed at $p_0$ together with the partitions and the test matrices, so its value at $p_0$ is a valid input at every prime $p\ge p_0$ (\cref{lem:spectral-monotone,lem:majorant}). Floating point only proposes the rational parameters; the exact tests prove them. The route-B caps are extended from their endpoints in the same way (\cref{lem:record:monotone-endpoint}), with the two branches of \eqref{eq:spec:beta} checked as above. The twelve-label grids are listed in \cref{tab:data:layer12-grid}, and the grid of the cut L20 of \cref{subsec:middle-l20} in \cref{tab:data:l20-grid}. The caps of the upper range are recorded in the certificates of \cref{sec:upper-reference} and in \cref{cert:upper-lower-bands}, and \cref{tab:data:upper-bands} lists the band inputs. \end{remark} \subsection{Primes \texorpdfstring{$p\equiv1\pmod4$}{p = 1 (mod 4)}: extra terms (large primes only)}\label{subsec:advance:parity} This subsection is used only at the tail primes $p\ge\Pfour=2^{512}$ with $p\equiv1\pmod4$ (\cref{subsec:tail-law}). At every other prime of the construction where a spectral cap is used, $p\equiv3\pmod4$ and $t_J=0$ (\cref{lem:spec2:paley}(c)). At $p\equiv1\pmod4$ the degree-one matrices $\mathbf A_{1,\pm}=\pm\Delta^E$ are real symmetric, the two signs of \eqref{eq:spectral-test} are distinct tests, the model is $\Hmat^+=\Hmat+\Hmat^{\rm cov}$ (\cref{def:coupling-model}), and the non-coverable sets enter $\eta_B$ through $\eps_{\rm par}=\bar\zeta\Lambda_{\rm nc}$ (\cref{cor:spec2:coupling}). It remains to supply admissible values of $\bar\zeta$. \begin{lemma}[Class-one Paley terms]\label{lem:spec2:paley-one} Let $p\equiv1\pmod4$, assume $e_\Delta(p,2n)<1$, and let coupling data be given. For every $J\subseteq U^+$ with $|J|\ge2$ and every $x\in\mathcal I^+$, $|S_J(x_J)|\le r$; in particular $|t_J|\le r$. If $J$ is not coverable, then \[ |t_J|\le\zeta r,\qquad \zeta=(R_\nu R_{\rm full}-1)+\frac n{(p-n)r},\qquad R_{\rm full}=\prod_{i\in U^+}\frac{1+e_{d^0_i}(p,n)}{1-e_{d^0_i}(p,n)} . \] In instance \textup{(A)}, $R_\nu R_{\rm full}=\Rcut R_{\rm full}$. \end{lemma} \begin{proof} $|S_J|\le\norm{g_J}^2\norm C\le r$. Let $j\in J$ be isolated in $G^+[J]$, and let $u_{\rm cons}$ be the uniform law on $\operatorname{Inj}_p(G^+[J])$. By \cref{lem:graphs:vertex}\ref{it:vertex:subset} for $G^+$ and the density bound (i) of the coupling data, the law $\nu_J$ of $x_J$ under $\nu$ is $w\,u_{\rm cons}/\E_{u_{\rm cons}}w$ with $\max w/\min w\le R_\nu R_{U^+\setminus J}\le R:=R_\nu R_{\rm full}$. Since $w/\E w\in[1/R,R]$ and $|S_J|\le r$, $|t_J-\E_{u_{\rm cons}}S_J|=|\E_{u_{\rm cons}}[(w/\E w-1)S_J]|\le(R-1)r$. Under $u_{\rm cons}$, given $x_{J\setminus\{j\}}$ the label $x_j$ is uniform on the $p-|J|+1$ values not used, because $j$ has no edge in $G^+[J]$. Write $S_J=\E_{a,b}\chi(b-a)\chi(a-x_j)\chi(b-x_j) g_{J\setminus\{j\}}(a)g_{J\setminus\{j\}}(b)$. The terms $a=b$ vanish, and for $a\ne b$, $|\sum_{t\notin x(J\setminus\{j\})}\chi((a-t)(b-t))|\le1+(|J|-1)$ by \eqref{eq:two-root}; so $|\E_{u_{\rm cons}}S_J|\le|J|/(p-|J|+1)\le n/(p-n)$. Hence $|t_J|\le\zeta r$. \end{proof} So $\bar\zeta=\zeta$ is admissible in \cref{cor:spec2:coupling}; the ten nonroot cuts use it. At the root cuts the constant $\zeta$ (with $R_\nu=\Rcut$ in instance~\textup{(A)}) is larger at every stored threshold than the bound of the transfer below, which replaces it there. \begin{lemma}[Transfer of the non-coverable Paley averages]\label{lem:spec2:parity-transfer} Let $p\equiv1\pmod4$, take instance \textup{(A)}, and let $\eps_\varrho\ge\norm{\varrho-1}_\mu$. Then for every $J$ with $|J|\ge2$ that is not coverable, \[ \frac{|t_J|}r\le R_{\rm full}-1+\frac n{(p-n)r}+\eps_\varrho . \] Consequently $\bar\zeta=\min\{\zeta,\ R_{\rm full}-1+n/((p-n)r)+\eps_\varrho\}$ is admissible in \cref{cor:spec2:coupling}. \end{lemma} \begin{proof} Here $t_J=\E_{m_p}S_J$. Since $|S_J|\le r$ pointwise, Cauchy--Schwarz gives $|\E_{m_p}S_J-\E_\mu S_J|=|\E_\mu[(\varrho-1)S_J]|\le\eps_\varrho r$. The isolated-vertex argument of \cref{lem:spec2:paley-one} for $\nu=\mu$ ($R_\nu=1$) gives $|\E_\mu S_J|\le(R_{\rm full}-1+n/((p-n)r))r$. \end{proof} The certificate applies the transfer only at the root cuts LL20 and LL22, with $\eps_\varrho=R_Z(M_\star+N_{\rm ns}+D_{\rm col})$, the constant coupling of \cref{prop:spec2:mucentre}\ref{it:centre:rho}; there it gives the smaller value at every stored threshold, and the stored class-one root caps, which are inputs of the tail law, are computed with it. Every quantity is admissible (\cref{lem:spectral-monotone}), so the value at the threshold covers all larger primes of the class. Sharper class-one bounds recorded in \cref{subsec:obs:tested} are not used by any certificate of the construction. \paragraph{Consequences and what to read next.} This section used the following inputs; its outputs are the two criteria and the exact star synthesis above. From Part~II: Weil's bound, the two-root identity, Gauss sums and the Paley operator (\cref{thm:weil,thm:gauss,lem:square-shift}, \eqref{eq:two-root}); maximal correlation (\cref{def:prelim:maxcorr}); admissible majorants (\cref{def:majorant,lem:majorant}). From Part~IV: the extension count, the sequential counts and the conditional laws of graph laws (\cref{lem:extension,lem:graphs:sequential,lem:graphs:vertex}, \eqref{eq:graphs:graded}); spectral data, the cut kernel, the positive envelope and the block lift (\cref{def:spec:data,lem:spec:elementary,lem:spec:cutkernel,prop:matching:positive,lem:spec:tensorcomp}); weighted frames (\cref{lem:weighted-frame}), in \cref{subsec:spec:actual-stars}; the star-trace dictionary and the star function (\cref{lem:star-trace}, \eqref{eq:star-function}); the two-variable sum \cref{thm:dl:H2} with \eqref{eq:dl:B}; and the witness kernel \cref{lem:matching:kernel}. As inputs of the criteria (not used in their proofs): the nonstar and coincidence bounds (\cref{lem:advance:compressed-partition,lem:matching:extractionk,cor:extraction-leaf,lem:oct24-collision}) and the ordered-star bounds (\cref{prop:advance:ordered-star,lem:star-mean}). No input of \cref{subsec:spec:actual-stars} comes from the two criteria. \space % End sections/14_spectral % Begin sections/15_second_order \section{Second-order character sums: \texorpdfstring{$O(p^{-1})$}{O(p\textasciicircum (-1))} where Weil gives \texorpdfstring{$O(p^{-1/2})$}{O(p\textasciicircum (-1/2))}}\label{sec:dl} \paragraph{What this section proves and how to read it.} A bound is \emph{second order} if it is $O(r^2)=O(1/p)$ where one Weil bound gives $O(r)$. Three such bounds are proved, for a four-cycle kernel, a two-variable sum, and trace functions with one free label (called \emph{moving pinned values} below; ``root'' in lemma names refers to pinned values, not to the Part~V principal law). A reader willing to accept \cref{thm:dl:K,thm:dl:H2} as stated can skip the sheaf arguments; external inputs are collected in \cref{app:external}. Weil's bound gives square-root cancellation in a sum of one quadratic character of one polynomial; after the normalizations of the local laws this square-root cancellation is a relative error of order $r=p^{-1/2}$. The spectral criteria of \cref{sec:spectral}, as they are applied in Part~V, are conditional: part of a labelling is fixed, and the joint law of the remaining labels is compared with a product law. Errors of two one-variable counts can then correlate, and several terms must be of order $r^2$, uniformly in the fixed labels. This section proves the three second-order estimates the construction needs, in the generality in which they are used. No graph occurs in \cref{subsec:dl:K,subsec:dl:H2}, and \cref{subsec:moving-root} uses a half law only through its one-vertex conditional laws, except for the density bound of \cref{lem:wt:stars}(a), which uses the tuple densities of a graph law. \begin{enumerate}[label=(\arabic*)] \item \emph{The four-cycle kernel} $\chi\big(\prod_{i,j\le2}(y_j-x_i)\big)$ on ordered pairs of distinct labels has norm at most $2/p=2r^2$ for uniform probability (\cref{thm:dl:K,cor:dl:normalized}), where Cauchy--Schwarz gives only $r$. This is the norm of a decided complete rectangle (one all of whose pairs are present or absent; \cref{subsec:extraction:partition}) in the witness kernels (\cref{lem:matching:kernel}) and of the $K_{2,2}$ core of the completion variance (\cref{lem:push:localvariance}). Split along the diagonal of two auxiliary labels, it bounds the remainder of the raw pair maps by order $q=1/p$ (\cref{cor:raw-pair-maps}): this bound is used for the positive roots of the late middle pieces (\cref{sec:positive-roots}). \item \emph{The two-variable sum} $\sum_{y,z}\chi\big(f(y)g(z)(y-z)\big)$ with split squarefree $f,g$ is $O(p)$ rather than $O(p^{3/2})$ (\cref{thm:dl:H2}). It bounds the complete conditional means of the product rows (\cref{subsec:advance:product-rows}) and the pair term of the completion variance. It also bounds the conditional pivot means of weighted star marginals (\cref{lem:wt:stars}), which bound the higher-star marginals ($|T|\ge3$ in \cref{lem:wt:stars}) of the dense comparisons and of the six-query mixture of the upper range (\cref{prop:dense-comparison,prop:le-mixture}). \item \emph{The moving-root traces} $\tau_S$ describe the integrated-centre stars of a cut kernel once all labels but one are fixed. They are almost orthogonal for distinct root sets, also against character weights (\cref{lem:moving-root-moments}). Ordered pivot groups turn this into the star marginal $M_\star$ and the star mean $z_\star$ of the upper root (\cref{prop:advance:ordered-star,lem:star-mean}), which enter \cref{lem:record:direct-star-inputs,lem:upper-completed-root}; the uniform forms of the moments enter the conditional row bounds of the product rows (\cref{cor:moving-root-uniform,cor:moving-root-conditional}). \end{enumerate} The first estimate is representation theory of $\mathrm{PGL}_2(\Fp)$ together with Jacobi sums. The second and third come from Deligne's theorem applied to the Katz--Sarnak sheaves of the family of curves $y^2=f(x)(x-z)$; the external inputs are stated in \cref{app:external}. One further second-order input is not proved here: the twisted second moment $\sum_\lambda\chi(\lambda)T_\lambda^2$ of the Legendre traces $T_\lambda=\sum_y\chi\big(y(y-1)(y-\lambda)\big)$, to which the graph moment $M_{G_5}$ behind the variance savings (the graph $G_5$ and its moment are defined in \cref{lem:record:weighted-moment}) reduces, is evaluated through a cusp form of weight four (\cref{thm:ahlgren-ono}) and enters \cref{lem:record:weighted-moment} directly. \Cref{subsec:second-order-uses} lists where each estimate enters. Throughout, $p$ is an odd prime, $r=p^{-1/2}$, $\chi=\chi_p$ is the quadratic character with $\chi(0)=0$, and $\E_x$ is the average over $x\in\Fp$. \subsection{The four-cycle kernel}\label{subsec:dl:K} For four distinct points, the character kernel of a complete rectangle $K_{2,2}$ is the quadratic character of a cross-ratio (it is $0$ when points coincide), so it is invariant under $\mathrm{PGL}_2(\Fp)$ acting on pairs of points of the projective line. The permutation representation on ordered pairs of distinct points is induced from the split torus and has multiplicities at most two, so the kernel acts by computable scalars on all but one isotypic component. The scalars are twisted sums over the split and the nonsplit torus: products of two Jacobi sums and squares of sums of modulus $\sqrt p$. This gives spectral norm at most $2p$ for the character matrix (\cref{thm:dl:K}), that is $2/p$ after normalisation by counting measure (\cref{cor:dl:normalized}). \paragraph{Notation.} Points of $\mathbb P^1=\mathbb P^1(\Fp)$ are represented by the column vectors $(u,1)^{\mathsf T}$, $u\in\Fp$, and $\infty=(1,0)^{\mathsf T}$; for column vectors $a=(a_0,a_1)^{\mathsf T}$, $b=(b_0,b_1)^{\mathsf T}$ put $a\wedge b=a_0b_1-a_1b_0$. Let $\mathcal X=\{(x_1,x_2)\in\mathbb P^1\times\mathbb P^1:x_1\ne x_2\}$, so $|\mathcal X|=p(p+1)$, and for $x,z\in\mathcal X$ let \begin{equation}\label{eq:dl:M} M(x,z)=\chi\Big(\prod_{i,j\in\{1,2\}}(z_i\wedge x_j)\Big), \end{equation} computed with the chosen representatives. For finite points $z_i\wedge x_j=z_i-x_j$, so on pairs of finite points $M(x,z)=\chi\big((z_1-x_1)(z_1-x_2)(z_2-x_1)(z_2-x_2)\big)$. We also write $M$ for the matrix $(M(x,z))_{x,z\in\mathcal X}$ and for the operator $(Mh)(x)=\sum_{z\in\mathcal X}M(x,z)h(z)$ on $\C^{\mathcal X}$ with the standard inner product $\ip hk=\sum_x\overline{h(x)}k(x)$. If $\{z_1,z_2\}\cap\{x_1,x_2\}=\emptyset$, the product in \eqref{eq:dl:M} is the cross-ratio $[z_1,z_2;x_1,x_2]=\frac{(z_1\wedge x_1)(z_2\wedge x_2)}{(z_1\wedge x_2)(z_2\wedge x_1)}$ times the nonzero square $\big((z_1\wedge x_2)(z_2\wedge x_1)\big)^2$, so $M(x,z)=\chi([z_1,z_2;x_1,x_2])$; otherwise $M(x,z)=0$. The cross-ratio does not depend on the representatives and is invariant under $\mathrm{GL}_2(\Fp)$. Thus $M(x,z)$ depends only on the orbit of the configuration $(x,z)$, which is why its spectrum can be computed by representation theory. Let $\Gamma=\mathrm{PGL}_2(\Fp)$, of order $p(p^2-1)$, acting on $\mathbb P^1$ by matrices on column vectors and diagonally on $\mathcal X$, and let $\Lambda(g)h(y)=h(g^{-1}y)$ be the permutation representation on $\C^{\mathcal X}$. We fix a nonsquare $D\in\Fp^\times$ and an element $\sqrt D\in\F_{p^2}$ with $(\sqrt D)^2=D$, so $\F_{p^2}=\Fp(\sqrt D)$; for $\zeta\in\F_{p^2}$, $\bar\zeta=\zeta^p$, $N\zeta=\zeta\bar\zeta\in\Fp$ and $\tr\zeta=\zeta+\bar\zeta\in\Fp$. Let $\mathsf U=\{s\in\F_{p^2}:Ns=1\}$, a cyclic group of order $p+1$ (the kernel of the norm, which maps $\F_{p^2}^\times$ onto $\Fp^\times$), and $\eta$ its unique character of order $2$; for $s\in\mathsf U$, $s^{-1}=\bar s$ and $\tr s=s+s^{-1}$. The map $\zeta\mapsto\zeta/\bar\zeta=\zeta^{1-p}$ is a homomorphism $\F_{p^2}^\times\to\mathsf U$ with kernel $\Fp^\times$, hence onto (orders $p^2-1$ and $p+1$); the elements $\zeta=m+\sqrt D$, $m\in\Fp$, together with $\zeta=1$ represent the cosets of $\Fp^\times$, and $\zeta=1$ is the one with $\zeta/\bar\zeta=1$. In $\Gamma$ we use the elements $u=\begin{psmallmatrix}1&1\\0&1\end{psmallmatrix}$, $h_a=\begin{psmallmatrix}a&0\\0&1\end{psmallmatrix}$ ($a\in\Fp^\times$), and, for $\xi\in\F_{p^2}\setminus\Fp$, the image $g_\xi$ in $\Gamma$ of the $\Fp$-linear map $\zeta\mapsto\xi\zeta$ of $\F_{p^2}=\Fp\oplus\Fp\sqrt D$ (in the basis $1,\sqrt D$); $g_\xi$ has the eigenvalues $\xi,\bar\xi$. Multiplicative characters vanish at $0$. \begin{lemma}[Invariance]\label{lem:dl:invariance} \begin{enumerate}[label=\textup{(\alph*)}] \item The value $M(x,z)$ does not depend on the chosen representatives. Moreover $M(x,z)=M(z,x)$, and $M(gx,gz)=M(x,z)$ for every $g\in\mathrm{GL}_2(\Fp)$. Hence $M$ is real symmetric and commutes with $\Lambda(g)$ for every $g\in\Gamma$. \item $\Gamma$ acts transitively on $\mathcal X$, and the stabilizer of $x_0=(0,\infty)$ is the image $\mathsf T=\{h_a:a\in\Fp^\times\}$ of the diagonal matrices, of order $p-1$. Hence $\C^{\mathcal X}\cong\mathrm{Ind}_{\mathsf T}^\Gamma\mathbf 1$. \end{enumerate} \end{lemma} \begin{proof} (a) For column vectors and $g\in\mathrm{GL}_2(\Fp)$, $(ga)\wedge(gb)=\det g\,(a\wedge b)$, and $(ca)\wedge b=c(a\wedge b)=a\wedge(cb)$. Each of the four points $x_1,x_2,z_1,z_2$ occurs in exactly two of the four factors $z_i\wedge x_j$. Replacing a representative $a$ by $ca$ ($c\in\Fp^\times$) therefore multiplies the product by $c^2$, and replacing every point by its image under $g$ multiplies it by $(\det g)^4$ times a product of squares of the normalizing constants of the images; in all cases the product is multiplied by a nonzero square, which does not change $\chi$. Moreover $\prod_{i,j}(x_i\wedge z_j)=\prod_{i,j}(-(z_j\wedge x_i))=\prod_{i,j}(z_i\wedge x_j)$, so $M$ is symmetric; it is real. If $g\in\Gamma$, then $(M\Lambda(g)h)(x)=\sum_zM(x,z)h(g^{-1}z)=\sum_zM(x,gz)h(z) =\sum_zM(g^{-1}x,z)h(z)=(\Lambda(g)Mh)(x)$. (b) Given $(x_1,x_2)\in\mathcal X$ with representatives $a_1,a_2$, the matrix with columns $a_1,a_2$ is invertible and maps $\infty=(1,0)^{\mathsf T}$ to $x_1$ and $0=(0,1)^{\mathsf T}$ to $x_2$; so $\Gamma$ is transitive on $\mathcal X$. A matrix fixing the points $0$ and $\infty$ has both standard basis vectors as eigenvectors, so it is diagonal, and its image in $\Gamma$ is some $h_a$. Since $|\Gamma|/|\mathsf T|=p(p+1)=|\mathcal X|$, the permutation representation on $\mathcal X$ is $\mathrm{Ind}_{\mathsf T}^\Gamma\mathbf 1$. \end{proof} \begin{lemma}[Classes and characters of $\Gamma$]\label{lem:dl:group} \begin{enumerate}[label=\textup{(\alph*)}] \item For $\xi\in\F_{p^2}\setminus\Fp$, the conjugacy class of $g_\xi$ in $\Gamma$ depends only on $s=\xi/\bar\xi\in\mathsf U\setminus\{1\}$; we write $g_s$ for it. Moreover $h_a$ is conjugate to $h_{1/a}$ and $g_s$ to $g_{1/s}$, and for every class function $F$ on $\Gamma$ \begin{equation}\label{eq:dl:classsum} \sum_{g\in\Gamma}F(g)=F(1)+(p^2-1)F(u) +\frac{p(p+1)}2\sum_{a\in\Fp^\times\setminus\{1\}}F(h_a) +\frac{p(p-1)}2\sum_{s\in\mathsf U\setminus\{1\}}F(g_s). \end{equation} \item The irreducible complex representations of $\Gamma$ are, up to isomorphism, the following, with the characters shown at $u$, $h_a$ ($a\ne1$) and $g_s$ ($s\ne1$): \begin{center}\small \begin{tabular}{@{}lllllr@{}} \toprule representation & dimension & $u$ & $h_a$ & $g_s$ & number\\ \midrule $\mathbf 1$ & $1$ & $1$ & $1$ & $1$ & $1$\\ $\mathrm{sgn}$ & $1$ & $1$ & $\chi(a)$ & $\eta(s)$ & $1$\\ $\mathrm{St}$ & $p$ & $0$ & $1$ & $-1$ & $1$\\ $\mathrm{St}\otimes\mathrm{sgn}$ & $p$ & $0$ & $\chi(a)$ & $-\eta(s)$ & $1$\\ $\pi(\mu)$, $\mu\in\widehat{\Fp^\times}$, $\mu^2\ne1$ & $p+1$ & $1$ & $\mu(a)+\bar\mu(a)$ & $0$ & $(p-3)/2$\\ $D_\nu$, $\nu\in\widehat{\mathsf U}$, $\nu^2\ne1$ & $p-1$ & $-1$ & $0$ & $-(\nu(s)+\bar\nu(s))$ & $(p-1)/2$\\ \bottomrule \end{tabular} \end{center} Here $\pi(\mu)\cong\pi(\bar\mu)$ and $D_\nu\cong D_{\bar\nu}$, and the last column is the number of isomorphism classes of each kind; all characters are real. $\mathrm{St}$ is the complement of $\mathbf 1$ in the permutation representation of $\Gamma$ on $\mathbb P^1$. \end{enumerate} \end{lemma} \begin{proof} We use \cref{thm:prelim:gl2} with $q=p$. Scaling a matrix does not change its type, so every $g\ne1$ in $\Gamma$ has a well-defined type (b), (c) or (d). (a) Let $\xi,\xi'\in\F_{p^2}\setminus\Fp$ with $\xi'/\bar\xi'\in\{\xi/\bar\xi,\bar\xi/\xi\}$. The multiplications by $\xi'$ and by $\bar\xi'$ have the same eigenvalues $\{\xi',\bar\xi'\}$, so they are conjugate in $\mathrm{GL}_2(\Fp)$ (\cref{thm:prelim:gl2}; explicitly, the $\Fp$-linear map $\zeta\mapsto\bar\zeta$ conjugates one into the other). Replacing $\xi'$ by $\bar\xi'$ if necessary, we may therefore assume $\xi'/\bar\xi'=\xi/\bar\xi$. Then $c=\xi'/\xi$ satisfies $\bar c=c$, so $c\in\Fp^\times$, and the multiplication by $\xi'=c\xi$ is $c$ times the multiplication by $\xi$; hence $g_{\xi'}=g_\xi$ in $\Gamma$. This shows that the class depends only on $s$ and that $g_s\sim g_{1/s}$. Similarly $h_{1/a}$ is the image of $\mathrm{diag}(1,a)$, which is conjugate to $\mathrm{diag}(a,1)$. For \eqref{eq:dl:classsum} we count the elements of $\Gamma$ of each type; each element of $\Gamma$ has exactly $p-1$ preimages in $\mathrm{GL}_2(\Fp)$. By \cref{thm:prelim:gl2}(iv), a conjugacy class of $\mathrm{GL}_2(\Fp)$ of type (b), (c) or (d) has $p^2-1$, $p(p+1)$ or $p(p-1)$ elements. \emph{Type (b).} For $x\in\Fp^\times$ the non-scalar matrices with characteristic polynomial $(T-x)^2$ form one class, so there are $(p-1)(p^2-1)$ such matrices and $p^2-1$ elements of type (b) in $\Gamma$. All of them are conjugate to $u$: the matrix $\begin{psmallmatrix}x&1\\0&x\end{psmallmatrix}$ represents the same element as $\begin{psmallmatrix}1&1/x\\0&1\end{psmallmatrix} =\mathrm{diag}(1/x,1)\,u\,\mathrm{diag}(1/x,1)^{-1}$. \emph{Type (c).} For $a\in\Fp^\times\setminus\{1\}$ let $C_a\subseteq\Gamma$ be the set of elements with a preimage whose eigenvalues are $x,ax$ for some $x$; then $C_a=C_{1/a}$, every element of $C_a$ is conjugate to $h_a$, and the $C_a$ partition the elements of type (c). The eigenvalue sets $\{x,ax\}$, $x\in\Fp^\times$, are $p-1$ distinct sets if $a\ne-1$ and $(p-1)/2$ if $a=-1$. So $|C_a|=p(p+1)$ for $a\ne\pm1$ and $|C_{-1}|=p(p+1)/2$. In the sum $\frac{p(p+1)}2\sum_{a\ne1}F(h_a)$ each set $C_a$ with $a\ne-1$ appears twice (as $a$ and $1/a$) with weight $\frac{p(p+1)}2$, and $C_{-1}$ once; so this sum is $\sum_{g\text{ of type (c)}}F(g)$. \emph{Type (d).} For $s\in\mathsf U\setminus\{1\}$ let $C'_s\subseteq\Gamma$ be the set of elements with a preimage whose eigenvalues $\xi,\bar\xi$ satisfy $\xi/\bar\xi\in\{s,1/s\}$; by \cref{thm:prelim:gl2} and the first part of (a), every element of $C'_s$ is conjugate to $g_s$. The equation $\xi/\bar\xi=s$ has $p-1$ solutions, and the eigenvalue sets $\{\xi,\bar\xi\}$ with $\xi/\bar\xi=s$ are $p-1$ distinct sets if $s\ne-1$ (since then $\bar\xi/\xi=1/s\ne s$) and $(p-1)/2$ if $s=-1$. So $|C'_s|=p(p-1)$ for $s\ne\pm1$ and $|C'_{-1}|=p(p-1)/2$, and as for type (c) the last sum in \eqref{eq:dl:classsum} is $\sum_{g\text{ of type (d)}}F(g)$. (The count $1+(p^2-1)+\frac{p(p+1)}2(p-2)+\frac{p(p-1)}2p=p^3-p$ confirms that every element is counted once.) (b) The irreducible representations of $\Gamma$ are those of $\mathrm{GL}_2(\Fp)$ on which the scalar matrices act trivially. By \cref{thm:prelim:gl2}(iii) and Schur's lemma (a scalar matrix acts on an irreducible representation by its character value divided by the dimension), the scalar $xI$ acts on $U_\alpha$ and on $V_\alpha$ by $\alpha(x)^2$, on $W_{\alpha,\beta}$ by $\alpha\beta(x)$ and on $X_\varphi$ by $\varphi(x)$. Hence the representations of $\Gamma$ are: $U_\alpha$, $V_\alpha$ with $\alpha^2=1$, that is $\alpha\in\{1,\chi\}$ (we put $\mathbf 1=U_1$, $\mathrm{sgn}=U_\chi$, $\mathrm{St}=V_1$, $\mathrm{St}\otimes\mathrm{sgn}=V_\chi$); $W_{\mu,\bar\mu}=:\pi(\mu)$ with $\mu\ne\bar\mu$, that is $\mu^2\ne1$; and $X_\varphi$ with $\varphi|_{\Fp^\times}=1$ and $\varphi^p\ne\varphi$. A character $\varphi$ of $\F_{p^2}^\times$ trivial on $\Fp^\times$ factors through the surjection $\zeta\mapsto\zeta/\bar\zeta$ onto $\mathsf U$: $\varphi(\zeta)=\nu(\zeta/\bar\zeta)$ for a unique $\nu\in\widehat{\mathsf U}$; since $(\zeta/\bar\zeta)^p=\bar\zeta/\zeta$, $\varphi^p=\varphi$ iff $\bar\nu=\nu$ iff $\nu^2=1$; we put $D_\nu=X_\varphi$. The isomorphisms are those of \cref{thm:prelim:gl2}(ii), and the numbers follow ($p-3$ characters $\mu$ of $\Fp^\times$ and $p-1$ characters $\nu$ of $\mathsf U$ have square $\ne1$). The values: $u$ is of type (b) with $x=1$, $h_a$ of type (c) with $(x,y)=(a,1)$, and $g_\xi$ of type (d) with $\zeta=\xi$; so $\varphi(\xi)+\varphi(\bar\xi)=\nu(s)+\nu(\bar s)=\nu(s)+\bar\nu(s)$. Finally $\xi\mapsto\chi(N\xi)$ is a character of $\F_{p^2}^\times$ that is trivial on $\Fp^\times$ ($Nc=c^2$) and nontrivial (the norm is onto $\Fp^\times$), so it is $\nu_0(\xi/\bar\xi)$ with $\nu_0$ of order $2$, that is $\chi(N\xi)=\eta(s)$; this gives the values of $\mathrm{sgn}$ and $\mathrm{St}\otimes\mathrm{sgn}$ at $g_s$. All values are real. \end{proof} \begin{lemma}[Decomposition]\label{lem:dl:decomp} As a representation of $\Gamma$, \[ \C^{\mathcal X}\cong\mathbf 1\oplus\mathrm{St}^{\oplus2} \oplus(\mathrm{St}\otimes\mathrm{sgn}) \oplus\bigoplus_{\{\mu,\bar\mu\}}\pi(\mu)\oplus\bigoplus_{\{\nu,\bar\nu\}}D_\nu, \] the sums over the unordered pairs with $\mu^2\ne1$, resp.\ $\nu^2\ne1$; $\mathrm{sgn}$ does not occur. \end{lemma} \begin{proof} By \cref{lem:dl:invariance}(b) and Frobenius reciprocity, the multiplicity of an irreducible $\pi$ is $m_\pi=\dim\pi^{\mathsf T}=\frac1{p-1}\sum_{a\in\Fp^\times}\chi_\pi(h_a) =\frac1{p-1}\big(\dim\pi+\sum_{a\ne1}\chi_\pi(h_a)\big)$. With the table of \cref{lem:dl:group}(b) and $\sum_{a\ne1}\chi(a)=-1$, $\sum_{a\ne1}(\mu+\bar\mu)(a)=-2$ ($\mu\ne1$): $m_{\mathbf 1}=1$, $m_{\mathrm{sgn}}=0$, $m_{\mathrm{St}}=\frac{p+p-2}{p-1}=2$, $m_{\mathrm{St}\otimes\mathrm{sgn}}=1$, $m_{\pi(\mu)}=\frac{p+1-2}{p-1}=1$, $m_{D_\nu}=1$. (Check: $1+2p+p+\frac{p-3}2(p+1)+\frac{p-1}2(p-1)=p(p+1)$.) \end{proof} \begin{lemma}[Eigenvalue on a multiplicity-one constituent]\label{lem:dl:schur} Let $\pi$ be an irreducible representation of $\Gamma$ of multiplicity one in $\C^{\mathcal X}$, and $V_\pi$ its isotypic subspace. Then $M$ acts on $V_\pi$ as the scalar \[ \lambda_\pi=\frac1{|\Gamma|}\sum_{g\in\Gamma}\chi_\pi(g)\,\Phi(g),\qquad \Phi(g)=\sum_{x\in\mathcal X}M(x,gx). \] $\Phi$ is a class function. \end{lemma} \begin{proof} $M$ commutes with $\Lambda(\Gamma)$ (\cref{lem:dl:invariance}(a)), so it preserves $V_\pi\cong\pi$ and acts there by a scalar $\lambda_\pi$ (Schur's lemma). $P_\pi=\frac{\dim\pi}{|\Gamma|}\sum_g\overline{\chi_\pi(g)}\Lambda(g)$ is the orthogonal projection onto $V_\pi$, so $\lambda_\pi\dim\pi=\mathrm{Tr}(MP_\pi) =\frac{\dim\pi}{|\Gamma|}\sum_g\overline{\chi_\pi(g)}\,\mathrm{Tr}(M\Lambda(g))$. The matrix of $\Lambda(g)$ has the entries $[y=gx]$, so $\mathrm{Tr}(M\Lambda(g))=\sum_xM(x,gx)=\Phi(g)$; the characters are real (\cref{lem:dl:group}(b)). $\Phi(kgk^{-1})=\Phi(g)$ by the substitution $x\mapsto kx$ and \cref{lem:dl:invariance}(a). \end{proof} For $a\in\Fp^\times$ put $\Upsilon(a)=\sum_{t\in\Fp}\chi\big(t(a-t)(at-1)\big)$, and for $s\in\mathsf U$ put $R(s)=\sum_{t\in\mathsf U\setminus\{1\}}\chi(\tr s-\tr t)$. \begin{lemma}[The function $\Phi$]\label{lem:dl:Phi} \begin{enumerate}[label=\textup{(\roman*)}] \item $\Phi(1)=0$ and $\Phi(u)=-p(1+\chi(-1))$. \item $\Phi(h_a)=(p-1)(\Upsilon(a)-1)$ for $a\ne1$; $\Upsilon(1/a)=\Upsilon(a)$ and $\Upsilon(1)=-\chi(-1)$. \item $\Phi(g_s)=-(p+1)\,\eta(s)\,R(s)$ for $s\in\mathsf U\setminus\{1\}$. \end{enumerate} \end{lemma} \begin{proof} (i) $x_1\wedge x_1=0$, so $M(x,x)=0$. The element $u$ maps $(v,1)^{\mathsf T}$ to $(v+1,1)^{\mathsf T}$ and fixes $\infty$. If $x$ contains $\infty$, the factor $(u\infty)\wedge\infty$ vanishes. For finite $x$ with $d=x_1-x_2\ne0$ the four factors $(ux)_i-x_j$ are $1$, $1+d$, $1-d$, $1$, so $\Phi(u)=p\sum_{d\ne0}\chi(1-d^2)$. Now $\sum_{d\in\Fp}\chi(1-d^2)=\chi(-1)\sum_d\chi((d-1)(d+1))=-\chi(-1)$ by the two-root identity \eqref{eq:two-root}, and the term $d=0$ is $1$; so $\Phi(u)=p(-\chi(-1)-1)$. (ii) $h_a$ fixes $0$ and $\infty$, so pairs containing one of them contribute $0$. For $x_1,x_2\in\Fp^\times$ write $x_2=tx_1$, $t\notin\{0,1\}$; the four factors are $(a-1)x_1$, $(a-t)x_1$, $(at-1)x_1$, $(a-1)tx_1$, with product $(a-1)^2x_1^4\,t(a-t)(at-1)$. Hence $\Phi(h_a)=(p-1)\sum_{t\ne0,1}\chi(t(a-t)(at-1))=(p-1)(\Upsilon(a)-1)$: the term $t=0$ of $\Upsilon(a)$ is $0$ and the term $t=1$ is $\chi((a-1)^2)=1$. Next, $\Upsilon(1/a)=\sum_t\chi\big(t(1-at)(t-a)a^{-2}\big)=\Upsilon(a)$, and $\Upsilon(1)=\sum_t\chi(-t(t-1)^2)=\sum_{t\ne1}\chi(-t)=-\chi(-1)$. (iii) Identify $\Fp^2$ with $\F_{p^2}$ by $(a_0,a_1)\mapsto\alpha=a_0+a_1\sqrt D$. For $\alpha$, $\beta$ corresponding to $a$, $b$ one checks $\bar\alpha\beta-\alpha\bar\beta=2\sqrt D(a_0b_1-a_1b_0)$, so $a\wedge b=(\bar\alpha\beta-\alpha\bar\beta)/(2\sqrt D)$. The points of $\mathbb P^1$ are the cosets $\F_{p^2}^\times/\Fp^\times$, and $g_\xi$ acts by multiplication by $\xi$. The multiplications by elements of $\F_{p^2}^\times$ form a subgroup of $\mathrm{GL}_2(\Fp)$ whose image $\mathsf T'\subseteq\Gamma$ acts simply transitively on $\mathbb P^1$ and commutes with $g_\xi$. For $k\in\mathsf T'$, $M(kx,g_\xi kx)=M(kx,kg_\xi x)=M(x,g_\xi x)$ by \cref{lem:dl:invariance}(a); every $x\in\mathcal X$ is mapped by exactly one $k\in\mathsf T'$ to a pair with first point $[1]$, so $\Phi(g_\xi)=(p+1)\sum_wM\big(([1],[w]),([\xi],[\xi w])\big)$, the sum over the $p$ cosets $[w]\ne[1]$. The numerators $2\sqrt D(z_i\wedge x_j)$ of the four factors are $\bar\xi-\xi$, $\bar\xi w-\xi\bar w$, $\bar\xi\bar w-\xi w$ and $N(w)(\bar\xi-\xi)$, and the common denominator $(2\sqrt D)^4=16D^2$ is a square. Write $\xi=\xi_0+\xi_1\sqrt D$ with $\xi_1\ne0$; then $(\bar\xi-\xi)^2=4\xi_1^2D$ is a nonsquare. Further \[ (\bar\xi w-\xi\bar w)(\bar\xi\bar w-\xi w)=N(w)\tr(\xi^2)-N(\xi)\tr(w^2) =N(w)N(\xi)\big(\tr s-\tr t\big),\qquad s=\xi/\bar\xi,\ t=w/\bar w, \] since $\tr(\zeta^2)/N\zeta=\zeta/\bar\zeta+\bar\zeta/\zeta$. Hence the summand is $-\chi(N\xi)\chi(\tr s-\tr t)=-\eta(s)\chi(\tr s-\tr t)$ (\cref{lem:dl:group}(b) for $\chi(N\xi)=\eta(s)$), and as $[w]$ runs over the cosets $\ne[1]$, $t=w/\bar w$ runs over $\mathsf U\setminus\{1\}$ bijectively. \end{proof} We also need two identities. Let $s\in\mathsf U\setminus\{1\}$ and write $s=w/\bar w$ with $w=m+\sqrt D$. Then $\tr s-2=-(s-1)(\bar s-1)=-N(s-1)$ and $s-1=(w-\bar w)/\bar w=2\sqrt D/\bar w$, so $N(s-1)=-4D/N(w)$ and $\chi(\tr s-2)=\chi(D)\chi(Nw)=-\eta(s)$. Since $\chi(2-\tr t)=\chi(-1)\chi(\tr t-2)$ and $\sum_{t\in\mathsf U}\eta(t)=0$, \begin{equation}\label{eq:dl:trace2} \sum_{t\in\mathsf U}\chi(2-\tr t)=\chi(-1),\qquad \sum_{s\in\mathsf U}\psi(s)\chi(\tr s-2)=-\sum_{s\ne1}(\psi\eta)(s)=1 \quad(\psi\in\widehat{\mathsf U},\ \psi\ne\eta). \end{equation} For $\psi\in\widehat{\mathsf U}$ and $\mu\in\widehat{\Fp^\times}$ put \[ \mathcal N(\psi)=\sum_{s,t\in\mathsf U}\psi(s)\chi(\tr s-\tr t),\qquad \mathcal S(\mu)=\sum_{a\in\Fp^\times}\mu(a)\Upsilon(a), \] and let $\Jac(\psi_1,\psi_2)=\sum_{v\in\Fp}\psi_1(v)\psi_2(1-v)$ be the Jacobi sum of \cref{thm:jacobi}. Since $\tr(s^{-1})=\tr s$ and $\Upsilon(1/a)=\Upsilon(a)$, $\mathcal N(\bar\psi)=\mathcal N(\psi)$ and $\mathcal S(\bar\mu)=\mathcal S(\mu)$. Since $\Fp^\times\subseteq\F_{p^2}^\times$ is a subgroup of a finite abelian group, $\chi$ extends to a character $\tilde\chi$ of $\F_{p^2}^\times$; we fix one ($\tilde\chi(0)=0$). For $\kappa\in\widehat{\mathsf U}$ put $\mathcal C(\kappa)=\sum_{v\in\mathsf U}\kappa(v)\tilde\chi(v-1)$. \begin{lemma}[Line sums]\label{lem:dl:line} Let $\Xi$ be a character of $\F_{p^2}^\times$ whose restriction to $\Fp^\times$ is nontrivial, and $\alpha\in\F_{p^2}\setminus\Fp$. Then $\big|\sum_{m\in\Fp}\Xi(m+\alpha)\big|=\sqrt p$. \end{lemma} \begin{proof} $m+\alpha\ne0$ for all $m$, and $|\sum_m\Xi(m+\alpha)|^2=p+\sum_{m\ne n}\Xi\big(\frac{m+\alpha}{n+\alpha}\big)$. We claim that $(m,n)\mapsto w=\frac{m+\alpha}{n+\alpha}$ is a bijection from $\{(m,n)\in\Fp^2:m\ne n\}$ onto $\F_{p^2}\setminus\Fp$. If $w=c\in\Fp$, then $(1-c)\alpha=cn-m\in\Fp$, which forces $c=1$ and $m=n$; so the map lands in $\F_{p^2}\setminus\Fp$. Given $w\notin\Fp$, the elements $1,w$ are a basis of $\F_{p^2}$ over $\Fp$, so $m-wn=(w-1)\alpha$ has exactly one solution $(m,n)\in\Fp^2$, and $m\ne n$ (otherwise $(w-1)(m+\alpha)=0$, impossible); this solution is the unique preimage. Hence the last sum is $\sum_{\F_{p^2}^\times}\Xi-\sum_{\Fp^\times}\Xi=0-0$, because $\Xi$ is nontrivial on $\Fp^\times$, hence on $\F_{p^2}^\times$. \end{proof} \begin{lemma}[Torus sums]\label{lem:dl:split} \begin{enumerate}[label=\textup{(\alph*)}] \item Let $C$ be a cyclic group of even order, $-1$ its element of order two, $\psi$ a character of $C$ and $F:C\to\C$. If $\psi(-1)=-1$ then $\sum_{y\in C}\psi(y)F(y^2)=0$. If $\psi(-1)=1$ then $\sum_{y\in C}\psi(y)F(y^2)=\sum_\kappa\sum_{w\in C}\kappa(w)F(w)$, the sum over the two characters $\kappa$ of $C$ with $\kappa^2=\psi$. \item \emph{(Split torus.)} If $\mu(-1)=-1$ then $\mathcal S(\mu)=0$. If $\mu(-1)=1$, then \[ \mathcal S(\mu)=\chi(-1)\sum_{\kappa}\Jac(\kappa,\chi)\Jac(\bar\kappa\chi,\chi), \] the sum over the two characters $\kappa$ of $\Fp^\times$ with $\kappa^2=\bar\mu$. If $\mu^2\ne1$, or if $\mu=\chi$, then $|\mathcal S(\mu)|\le2p$. \item \emph{(Nonsplit torus.)} Let $\psi\in\widehat{\mathsf U}$ and $\rho=(\psi\bar{\tilde\chi})|_{\mathsf U}$. If $\rho(-1)=-1$ then $\mathcal N(\psi)=0$; otherwise $\mathcal N(\psi)=\sum_{\kappa}\mathcal C(\kappa)^2$, the sum over the two $\kappa\in\widehat{\mathsf U}$ with $\kappa^2=\rho$. Moreover $|\mathcal C(\kappa)|=\sqrt p$ for every $\kappa\in\widehat{\mathsf U}$; hence $|\mathcal N(\psi)|\le2p$ for every $\psi$. \end{enumerate} \end{lemma} \begin{proof} (a) If $\psi(-1)=-1$, the substitution $y\mapsto-y$ multiplies the sum by $\psi(-1)=-1$, so it vanishes. If $\psi(-1)=1$: the characters of $C$ form a cyclic group of even order, in which the characters with value $1$ at $-1$ form the subgroup of index two, that is the squares; so $\psi=\kappa_0^2$, and the characters with square $\psi$ are $\kappa_0$ and $\kappa_0\chi_C$, where $\chi_C$ is the character of order two of $C$. As $y\mapsto y^2$ is two-to-one onto the subgroup $C^2$ of squares and $\kappa_0+\kappa_0\chi_C=2\kappa_0\one_{C^2}$, $\sum_y\psi(y)F(y^2)=\sum_y\kappa_0(y^2)F(y^2)=2\sum_{w\in C^2}\kappa_0(w)F(w) =\sum_{w\in C}(\kappa_0+\kappa_0\chi_C)(w)F(w)$. (b) The terms $t=0$ of $\Upsilon$ vanish. For $t\ne0$ write $a=tb$; then $t(a-t)(at-1)=t^2(b-1)(t^2b-1)$. With $c=t^2b$ we have $\mu(a)=\bar\mu(t)\mu(c)$ and $\chi(b-1)=\chi(c-t^2)$, so \[ \mathcal S(\mu)=\sum_{c\ne0}\mu(c)\chi(c-1)\,I(c),\qquad I(c)=\sum_{t\ne0}\bar\mu(t)\chi(c-t^2). \] Apply (a) with $C=\Fp^\times$, $\psi=\bar\mu$ (so $\psi(-1)=\mu(-1)$) and $F(y)=\chi(c-y)$: if $\mu(-1)=-1$ then $I(c)=0$, and otherwise $I(c)=\sum_\kappa\sum_{y\ne0}\kappa(y)\chi(c-y)$. For $c\ne0$ the substitution $y=cv$ gives $\sum_y\kappa(y)\chi(c-y)=(\kappa\chi)(c)\Jac(\kappa,\chi)$. Hence $\mathcal S(\mu)=\sum_\kappa\Jac(\kappa,\chi)\sum_{c\ne0}(\mu\kappa\chi)(c)\chi(c-1)$, and $\mu\kappa=\bar\kappa$ (as $\kappa^2=\bar\mu$), while $\sum_c(\bar\kappa\chi)(c)\chi(c-1)=\chi(-1)\sum_c(\bar\kappa\chi)(c)\chi(1-c) =\chi(-1)\Jac(\bar\kappa\chi,\chi)$. Moduli: if $\mu^2\ne1$ then $\kappa^4\ne1$, so $\kappa\ne1$, $\kappa\ne\chi$; hence $\kappa$, $\chi$, $\kappa\chi$ and $\bar\kappa\chi$, $\chi$, $\bar\kappa\chi\cdot\chi=\bar\kappa$ are nontrivial, and \cref{thm:jacobi} gives $|\Jac|=\sqrt p$ for both Jacobi sums. If $\mu=\chi$ is even, i.e. $\chi(-1)=1$ ($p\equiv1\pmod4$), $\kappa$ has order $4$, so $\kappa\chi=\bar\kappa$ and $\bar\kappa\chi=\kappa$ are nontrivial, and again $|\Jac|=\sqrt p$. In both cases $|\mathcal S(\mu)|\le2p$; if $\mu=\chi$ is odd ($\chi(-1)=-1$), $\mathcal S(\chi)=0$. (c) For $s,t\in\mathsf U$, $\tr s-\tr t=(s-t)(st-1)/(st)\in\Fp$. Since $\tilde\chi$ restricts to $\chi$ on $\Fp^\times$ and is multiplicative, $\chi(\tr s-\tr t)=\tilde\chi(s-t)\tilde\chi(st-1)\bar{\tilde\chi}(st)$ (both sides vanish iff $t\in\{s,s^{-1}\}$). Put $t=sw$, $w\in\mathsf U$: the summand $\psi(s)\chi(\tr s-\tr t)$ becomes $\rho(s)\cdot\bar{\tilde\chi}(w)\tilde\chi(1-w)\cdot\tilde\chi(s^2w-1)$. So $\mathcal N(\psi)=\sum_{w}\bar{\tilde\chi}(w)\tilde\chi(1-w) \sum_{s\in\mathsf U}\rho(s)\tilde\chi(s^2w-1)$. Apply (a) with $C=\mathsf U$ (cyclic of even order $p+1$; note $-1\in\mathsf U$) and $F(y)=\tilde\chi(yw-1)$: the inner sum vanishes if $\rho(-1)=-1$, and otherwise it is $\sum_\kappa\sum_{y\in\mathsf U}\kappa(y)\tilde\chi(yw-1) =\sum_\kappa\bar\kappa(w)\mathcal C(\kappa)$ ($v=yw$). Finally $\bar{\tilde\chi}(w)\tilde\chi(1-w)=\tilde\chi(w^{-1}-1)$, and $\sum_w\bar\kappa(w)\tilde\chi(w^{-1}-1)=\mathcal C(\kappa)$ ($w\mapsto w^{-1}$). For $|\mathcal C(\kappa)|$: the map $z\mapsto z^{p-1}=\bar z/z$ sends $\F_{p^2}^\times$ onto $\mathsf U$ with kernel $\Fp^\times$, the coset of $1$ goes to $1$ (whose term $\tilde\chi(1-1)=0$ vanishes), and the cosets of $z=m+\sqrt D$, $m\in\Fp$, go bijectively to $\mathsf U\setminus\{1\}$. For such $z$, $\bar z/z-1=-2\sqrt D/z$. Hence, with the character $\Xi(z)=\kappa(z^{p-1})\bar{\tilde\chi}(z)$ of $\F_{p^2}^\times$, \[ \mathcal C(\kappa)=\tilde\chi(-2\sqrt D)\sum_{m\in\Fp}\Xi(m+\sqrt D), \] and $\Xi$ restricts to $\bar\chi=\chi\ne1$ on $\Fp^\times$, because $z\mapsto\kappa(z^{p-1})$ is trivial there. \Cref{lem:dl:line} with $\alpha=\sqrt D$ gives $|\mathcal C(\kappa)|=\sqrt p$. \end{proof} \begin{theorem}[Four-cycle operator norm]\label{thm:dl:K} For every odd prime $p$, every eigenvalue of the real symmetric matrix $M$ of \eqref{eq:dl:M} lies in $[-2p,2p]$. In particular every principal submatrix of $M$ (for instance the one indexed by the ordered pairs of distinct elements of $\Fp$) has spectral norm at most $2p$. \end{theorem} \begin{proof} By \cref{lem:dl:decomp} $\C^{\mathcal X}$ is the orthogonal sum of the isotypic subspaces, which $M$ preserves (it commutes with $\Lambda(\Gamma)$). We determine the eigenvalues on each. \emph{$\pi(\mu)$, $\mu^2\ne1$.} By \cref{lem:dl:schur}, \eqref{eq:dl:classsum}, \cref{lem:dl:Phi} and \cref{lem:dl:group}(b), \begin{align*} \lambda&=\frac1{|\Gamma|}\Big[(p^2-1)\Phi(u) +\frac{p(p+1)}2\sum_{a\ne1}(\mu+\bar\mu)(a)(p-1)(\Upsilon(a)-1)\Big]\\ &=-(1+\chi(-1))+\frac12\sum_{a\ne1}(\mu+\bar\mu)(a)(\Upsilon(a)-1). \end{align*} Since $\sum_{a\ne1}\mu(a)=-1$ and $\Upsilon(1)=-\chi(-1)$, $\sum_{a\ne1}\mu(a)(\Upsilon(a)-1)=\mathcal S(\mu)+\chi(-1)+1$, and likewise for $\bar\mu$ with $\mathcal S(\bar\mu)=\mathcal S(\mu)$. So $\lambda=\mathcal S(\mu)$, and $|\lambda|\le2p$ by \cref{lem:dl:split}(b). \emph{$D_\nu$, $\nu^2\ne1$.} Here $\chi_\pi(u)=-1$, $\chi_\pi(h_a)=0$, so $\lambda=(1+\chi(-1))+\frac12\sum_{s\ne1}(\nu+\bar\nu)(s)\eta(s)R(s)$. For $\psi\in\widehat{\mathsf U}$ with $\psi\ne\eta$, removing from $\mathcal N(\psi)$ the row $s=1$ and the column $t=1$ (whose common term $\chi(0)$ is $0$) gives, by \eqref{eq:dl:trace2}, $\sum_{s\ne1}\psi(s)R(s)=\mathcal N(\psi)-\chi(-1)-1$. With $\psi=\nu\eta$ and $\psi=\bar\nu\eta$ (both $\ne\eta$ as $\nu\ne1$) and $\mathcal N(\bar\nu\eta)=\mathcal N(\overline{\nu\eta})=\mathcal N(\nu\eta)$, we get $\lambda=\mathcal N(\nu\eta)$, and $|\lambda|\le2p$ by \cref{lem:dl:split}(c). \emph{$\mathrm{St}\otimes\mathrm{sgn}$.} Here $\chi_\pi(u)=0$, $\chi_\pi(h_a)=\chi(a)$, $\chi_\pi(g_s)=-\eta(s)$, so \begin{align*} \lambda&=\frac12\sum_{a\ne1}\chi(a)(\Upsilon(a)-1)+\frac12\sum_{s\ne1}R(s)\\ &=\frac12\big(\mathcal S(\chi)+\chi(-1)+1\big) +\frac12\big(\mathcal N(\mathbf 1)-\chi(-1)-1\big) =\frac12\big(\mathcal S(\chi)+\mathcal N(\mathbf 1)\big), \end{align*} and $|\lambda|\le2p$ by \cref{lem:dl:split}(b),(c). \emph{The trivial representation.} It is spanned by the constant function, with eigenvalue the row sum $\sum_zM(x_0,z)$, which is the same for all $x_0$ (transitivity). For $x_0=(0,\infty)$: with the representatives $(z_i,1)$, $(0,1)$, $(1,0)$ fixed above, $z_i\wedge0=z_i$ and $z_i\wedge\infty=-1$ for finite $z_i$, while $\infty\wedge\infty=0$; so $M(x_0,z)=\chi(z_1z_2)$ if $z_1,z_2\in\Fp$ and $0$ otherwise, and $\sum_{z_1\ne z_2}\chi(z_1z_2)=(\sum_{v}\chi(v))^2-\sum_v\chi(v^2)=-(p-1)$. \emph{$\mathrm{St}$ (multiplicity $2$).} Let $C(z,x)=\chi(z\wedge x)$ for $z,x\in\mathbb P^1$. Then $\sum_{z\in\mathbb P^1}C(z,x)C(z,x')=p\,[x=x']$: for $x=x'$ there are $p$ points $z\ne x$; for $x\ne x'$ both finite, $\sum_{z\in\Fp}\chi((z-x)(z-x'))=-1$ by \eqref{eq:two-root}, and the term $z=\infty$ is $\chi(1)^2=1$; for $x'=\infty$, $x$ finite, $\sum_{z\in\Fp}\chi(z-x)\chi(-1)=0$ and the term $z=\infty$ vanishes. Now $M(x,z)=\phi_x(z_1)\phi_x(z_2)$ with $\phi_x(z)=C(z,x_1)C(z,x_2)$, so $\sum_{z\in\mathbb P^1}\phi_x(z)=0$ and $\phi_x(z)^2=\one[z\notin\{x_1,x_2\}]$. For $f:\mathbb P^1\to\C$ with $\sum f=0$ put $F_1(x)=f(x_1)$, $F_2(x)=f(x_2)$. Then \[ (MF_1)(x)=\sum_{z_1}f(z_1)\phi_x(z_1)\sum_{z_2\ne z_1}\phi_x(z_2) =-\sum_{z_1}f(z_1)\phi_x(z_1)^2=-\sum_{z_1\notin\{x_1,x_2\}}f(z_1) =f(x_1)+f(x_2), \] and, $M(x,z)$ being symmetric in $(z_1,z_2)$, also $MF_2=F_1+F_2$. The space $V_1=\{F_1+F_2':\ \sum f=\sum f'=0\}$ (with $F'_2(x)=f'(x_2)$) has dimension $2p$ (if $f(x_1)+f'(x_2)=0$ for all $x_1\ne x_2$, then $f$ is constant, as $p+1\ge3$, hence $0$, and then $f'=0$), is $\Gamma$-invariant and is isomorphic to $\mathrm{St}\oplus\mathrm{St}$ (\cref{lem:dl:group}(b): $\mathrm{St}$ is the space of functions on $\mathbb P^1$ with sum $0$). Since $m_{\mathrm{St}}=2$, $V_1$ is the $\mathrm{St}$-isotypic subspace, and $M$ acts on it as the identity on $\mathrm{St}$ tensored with $\begin{psmallmatrix}1&1\\1&1\end{psmallmatrix}$, with eigenvalues $2$ and $0$. So every eigenvalue of $M$ is one of $\mathcal S(\mu)$, $\mathcal N(\nu\eta)$, $\frac12(\mathcal S(\chi)+\mathcal N(\mathbf 1))$, $-(p-1)$, $2$, $0$, all of modulus at most $2p$. A principal submatrix of a real symmetric matrix is a compression, so its norm is at most $\norm M\le2p$. \end{proof} Every application of \cref{thm:dl:K} in this paper needs it for normalized counting measure, for functions that vanish on noninjective tuples, and sometimes against conditional laws with bounded densities. We record these forms once. \begin{corollary}[The four-cycle kernel for uniform probability]\label{cor:dl:normalized} Let $a,b\ge2$, let $\varsigma_{ij}\in\{\pm1\}$ ($i\le a$, $j\le b$), and put \[ K(x,y)=\prod_{i\le a,\ j\le b}\chi\big(\varsigma_{ij}(y_j-x_i)\big) \qquad(x\in\Fp^a,\ y\in\Fp^b). \] \begin{enumerate}[label=\textup{(\alph*)}] \item If $f:\Fp^a\to\C$ vanishes on the tuples with $x_1=x_2$ and $h:\Fp^b\to\C$ on the tuples with $y_1=y_2$ (in particular, if both vanish on noninjective tuples), then, for uniform probability on $\Fp^a$ and $\Fp^b$, \begin{equation}\label{eq:dl:normalized} \Big|\E_{x,y}\overline{f(x)}\,K(x,y)\,h(y)\Big|\le\frac2p\,\norm f_2\norm h_2 . \end{equation} For $a=b=2$: the operator with kernel $K$ relative to uniform probability on $\Fp^2$, compressed to the functions that vanish on the diagonal, has norm at most $2/p=2r^2$. \item Let $\nu_1,\nu_2$ be probability measures on $\Fp^a$, $\Fp^b$ with $\nu_1\{x_1=x_2\}=\nu_2\{y_1=y_2\}=0$ and densities relative to uniform probability at most $D_1$, $D_2$. Then for $f\in L^2(\nu_1)$, $h\in L^2(\nu_2)$, \[ \Big|\E_{x\sim\nu_1,\,y\sim\nu_2}\overline{f(x)}\,K(x,y)\,h(y)\Big| \le\frac2p\sqrt{D_1D_2}\,\norm f_{\nu_1}\norm h_{\nu_2}. \] \end{enumerate} \end{corollary} \begin{proof} Since $\chi(\varsigma(y-x))=\chi(\varsigma)\chi(y-x)$, the signs multiply $K$ by a constant of modulus one; we take them equal to $1$. (a) First let $a=b=2$. For finite pairs $K(x,y)=M(x,y)$, and $f,h$ are supported on the set $\mathcal X_{\rm aff}$ of ordered pairs of distinct elements of $\Fp$. So the left side of \eqref{eq:dl:normalized} is $p^{-4}|\mathbf f^*M_{\rm aff}\mathbf h|$, where $M_{\rm aff}$ is the principal submatrix of $M$ on $\mathcal X_{\rm aff}$ and $\mathbf f$, $\mathbf h$ are the vectors of values. By \cref{thm:dl:K} this is at most $p^{-4}\cdot2p\,\norm{\mathbf f}_{\ell^2}\norm{\mathbf h}_{\ell^2} =p^{-4}\cdot2p\cdot p\norm f_2\cdot p\norm h_2=\frac2p\norm f_2\norm h_2$. For general $a,b$ fix $x'=(x_3,\dots,x_a)$ and $y'=(y_3,\dots,y_b)$. Then $K(x,y)=K_{2,2}\big((x_1,x_2),(y_1,y_2)\big)\,\alpha(x_1,x_2)\beta(y_1,y_2)c$, where $K_{2,2}$ is the kernel for $a=b=2$, $\alpha=\prod_{i\le22}\chi(y_j-x_i)$ have modulus at most one and depend on $(x',y')$. The sliced functions $f(\cdot,x')\alpha$ and $h(\cdot,y')\beta$ vanish on the diagonal, so the case $a=b=2$ bounds the inner average over $(x_1,x_2,y_1,y_2)$ by $\frac2p\norm{f(\cdot,x')}_2\norm{h(\cdot,y')}_2$. Averaging over the independent $x'$ and $y'$ and applying Cauchy--Schwarz separately in $x'$ and in $y'$ gives \eqref{eq:dl:normalized}. (b) Let $d_i$ be the density of $\nu_i$. The left side is $|\E_{x,y}\overline{(fd_1)(x)}K(x,y)(hd_2)(y)|$ for uniform probability, and $fd_1$, $hd_2$ vanish where $x_1=x_2$, resp.\ $y_1=y_2$. By (a) it is at most $\frac2p\norm{fd_1}_2\norm{hd_2}_2$, and $\norm{fd_1}_2^2=\E[d_1^2|f|^2]\le D_1\E[d_1|f|^2]=D_1\norm f_{\nu_1}^2$, and likewise for $h$. \end{proof} The positive roots of the late middle pieces (\cref{sec:positive-roots}) multiply a root kernel by a polynomial of degree two in quartic traces $\E_s\psi_y(s)\psi_{y'}(s)$ of two pairs of labels, built from the \emph{pair traces} $\psi_y(s)=\chi(s-y_0)\chi(s-y_1)$. The maps defined by pair traces are close to rank one in the sense of \eqref{eq:raw-pair-split} below ($\norm R^2\le c_0q^2$ there): their diagonal part is explicit, and their off-diagonal part is the four-cycle kernel, of norm $O(1/p)$ by \cref{cor:dl:normalized}. \begin{corollary}[Raw pair maps]\label{cor:raw-pair-maps} Let $p$ be an odd prime and $q=1/p$. Unless said otherwise every label is uniform on $\Fp$, and $L^2(\Fp^k)$ carries the uniform probability. For a pair $y=(y_0,y_1)$ of labels put $\psi_y(s)=\chi(s-y_0)\chi(s-y_1)$. \begin{enumerate}[label=\textup{(\alph*)}] \item The maps $h\mapsto\E_s\chi(s-a)h(s)$ ($h\in L^2(\Fp)$) and $F\mapsto\E_{s,t}\chi(s-a)\chi(t-a)F(s,t)$ ($F\in L^2(\Fp^2)$), into functions of $a\in\Fp$, have norms $r$ and $\sqrt{q(1-q)}\le r$. The \emph{raw pair map} $h\mapsto\E_s\psi_y(s)h(s)$ has norm $\sqrt{q(1-q)}$ into functions of $y\in\Fp^2$, and norm at most $r$ into functions of $y$ uniform on the ordered pairs of distinct labels. A tensor product of such maps on independent labels has the product of their norms as its norm. \item Let $y$ be uniform on the ordered pairs of distinct labels, let $S\colon L^2(\Fp^2)\to L^2(y)$ be the map $(SF)(y)=\E_{s,u}\psi_y(s)\psi_y(u)F(s,u)$, and let $d=\sqrt p\,\one_{s=u}$, a unit vector of $L^2(\Fp^2)$. Then \begin{equation}\label{eq:raw-pair-split} S=r(1-2q)\,\one\ip d{\cdot}+R,\qquad Rd=0,\qquad\norm R^2\le c_0q^2,\qquad c_0=\frac4{1-q}+2q . \end{equation} In detail, the space $L^2(\Fp^2)$ is the orthogonal sum of $\C d$, of the functions $Df$, where $(Df)(s,u)=\sqrt p\,\one_{s=u}f(s)$ and $f\in L^2_0(\Fp)$, and of the functions that vanish on the diagonal $\{s=u\}$. On the second space $(RDf)(y)=-qr\big(f(y_0)+f(y_1)\big)$ and $\norm{RDf}\le\sqrt2\,qr\norm f$; on the third, $R$ agrees with $S$ and has norm at most $2q/\sqrt{1-q}$. For every $y$ the row $(s,u)\mapsto\psi_y(s)\psi_y(u)-r(1-2q)\,d(s,u)$ of $R$ has norm at most one in $L^2(\Fp^2)$. \end{enumerate} \end{corollary} \begin{proof} By \eqref{eq:two-root}, $\E_a\chi(s-a)\chi(s'-a)=\one_{s=s'}-q$ for all $s,s'$. (a) The first map is the Paley operator $P$ of \cref{lem:square-shift}, of norm $r$ by part (c) there. Write $R_2$ for the second map and $R_3$ for the raw pair map into functions of $y\in\Fp^2$. Then \[ (R_2R_2^*g)(a)=\E_{a'}\big(\E_s\chi(s-a)\chi(s-a')\big)^2g(a'),\qquad (R_3^*R_3h)(s)=\E_{s'}\big(\E_{y_0}\chi(s-y_0)\chi(s'-y_0)\big)^2h(s'), \] and both kernels are $(\one_{a=a'}-q)^2=(1-2q)\one_{a=a'}+q^2$ (with $s,s'$ in place of $a,a'$ in the second). The operator with this kernel is $q(1-2q)$ times the identity on $L^2_0(\Fp)$ and $q(1-q)$ on the constants, so $\norm{R_2}=\norm{R_3}=\sqrt{q(1-q)}$. For $y$ uniform on distinct pairs: the uniform probability on $\Fp^2$ is $1-q$ times the law of $y$ plus $q$ times the uniform law on the diagonal, and on the diagonal $\E_{y_0}\psi_{(y_0,y_0)}(s)\psi_{(y_0,y_0)}(s')=\E_{y_0}\one_{y_0\notin\{s,s'\}} =1-2q+q\one_{s=s'}$; hence \[ \E_y\psi_y(s)\psi_y(s')=\frac{(1-2q)\one_{s=s'}+q^2-q(1-2q+q\one_{s=s'})}{1-q} =\frac{1-2q-q^2}{1-q}\one_{s=s'}-\frac{q(1-3q)}{1-q}, \] and the Gram operator of the raw pair map is $q(1-2q-q^2)/(1-q)\le q$ on $L^2_0(\Fp)$ and $q^2$ on the constants. Finally, the norm of a tensor product of operators is the product of their norms. (b) The map $D\colon L^2(\Fp)\to L^2(\Fp^2)$ is an isometry onto the functions supported on the diagonal, and $D\one=d$; this gives the orthogonal decomposition. Since $y_0\ne y_1$, $\psi_y(s)^2=\one_{s\notin\{y_0,y_1\}}$, so \[ (SDf)(y)=\sqrt p\,\E_{s,u}\one_{s=u}\psi_y(s)\psi_y(u)f(s) =r\,\E_s\one_{s\notin\{y_0,y_1\}}f(s)=r\,\E f-qr\big(f(y_0)+f(y_1)\big). \] For $f=\one$ this is $Sd=r(1-2q)\one$, and $\ip dd=1$ gives $Rd=0$. For $f\in L^2_0(\Fp)$, $\ip d{Df}=\E f=0$, so $RDf=SDf=-qr(f(y_0)+f(y_1))$; as $y_0$ and $y_1$ are uniform and $\E f(y_0)\overline{f(y_1)}=-\norm f^2/(p-1)$, $\norm{RDf}^2=2q^3\big(1-\frac1{p-1}\big)\norm f^2\le2q^3\norm f^2$. A function $F$ that vanishes on the diagonal has $\ip dF=0$, so $RF=SF$. The kernel $\psi_y(s)\psi_y(u)=\prod_{i\in\{0,1\}}\prod_{v\in\{s,u\}}\chi(v-y_i)$ is the kernel $K$ of \cref{cor:dl:normalized} with $a=b=2$, the pair $y$ in the role of $x$ and all signs $+1$. For $G\in L^2(y)$ let $\tilde G$ be its extension by zero to $\Fp^2$, so that $\norm{\tilde G}_{L^2(\Fp^2)}=(1-q)^{1/2}\norm G$. By \cref{cor:dl:normalized}(a), $\tilde G$ and $F$ vanishing on the diagonals, \[ \big|\ip G{SF}_{L^2(y)}\big| =\frac1{1-q}\Big|\E_{y\in\Fp^2}\overline{\tilde G(y)}\,(SF)(y)\Big| \le\frac1{1-q}\cdot\frac2p\,(1-q)^{1/2}\norm G\norm F =\frac{2q}{\sqrt{1-q}}\norm G\norm F . \] For a general $F=\lambda d+Df+F'$, with $f\in L^2_0(\Fp)$ and $F'$ vanishing on the diagonal, $RF=RDf+RF'$, and Cauchy--Schwarz gives $\norm{RF}^2\le\big(2q^3+\frac{4q^2}{1-q}\big)\big(\norm f^2+\norm{F'}^2\big) \le c_0q^2\norm F^2$. Finally, the row of $S$ at $y$ is $k_y(s,u)=\psi_y(s)\psi_y(u)$, of modulus at most one, so $\norm{k_y}\le1$; and $\ip d{k_y}=(Sd)(y)=r(1-2q)$, so the row of $R$ at $y$, $k_y-r(1-2q)d=k_y-\ip d{k_y}d$, is the orthogonal projection of $k_y$ onto $d^\perp$. \end{proof} \noindent For two pairs $y,y'$ of distinct labels the normalized quartic trace $H=r^{-1}\E_s\psi_y(s)\psi_{y'}(s)$ (the scores of the positive roots, \cref{def:positive-root}, are of this form) satisfies $H^2=q^{-1}\ip{k_y}{k_{y'}}$, where $k_y$ is the row of $S$ at $y$, and so, by (b), \[ H^2=(1-2q)^2+q^{-1}\ip{\rho_y}{\rho_{y'}},\qquad\rho_y=k_y-r(1-2q)\,d . \] The square of a score thus differs from the constant $(1-2q)^2$ by a Gram kernel of the rows of $R$, divided by $q$. With the notation of \cref{lem:swapped-rectangle} (in particular that this Gram kernel is positive semidefinite), the bound $\norm R^2\le c_0q^2$ turns this into an error of order $q$ in the square estimates of the positive roots (\cref{lem:root-square}). \begin{remark}[The constant $2$]\label{rem:dl:K-sharp} The formulas of the proof of \cref{thm:dl:K} reproduce the full spectrum of $M$ for every odd prime $p\le73$ (floating-point computations of two internal referees, the second up to $p\le89$; evaluating the formulas for every odd prime $p<2000$ gives $\max|\lambda|<2p$ throughout), and $\max|\lambda|/p$ reaches $2-4.4\cdot10^{-12}$ at $p=71$. These floating-point computations suggest that the constant $2$ is optimal; they do not prove optimality (and are not used). The exact finite consistency tests of \cref{thm:dl:K} are described in \cref{rem:cert:deligne-tests}; they are not used in any proof. \end{remark} % Begin sections/15a_cubic_resultant \subsection{The complete three-by-three character kernel} \label{subsec:cubic-resultant} The four-cycle estimate has a counterpart for three labels on each side. Here a polynomial Gram identity replaces the character table. The bound applies to the complete bipartite graph $K_{3,3}$; deleting one of its edges does not preserve the argument. \begin{theorem}[Squarefree cubic resultant]\label{thm:cubic-resultant} Let $p$ be an odd prime and let $\mathcal S_d$ be the monic squarefree polynomials of degree $d$ over $\Fp$. On counting-measure spaces, set \[ B_d(f,g)=\chi(\operatorname{Res}(g,f)), \qquad f\in\mathcal S_d,\quad g\in\mathcal S_3. \] Then $B_3^*B_3\preceq p^3I$. Consequently the kernel \[ \prod_{i,j=1}^3\chi(y_j-x_i) \] on uniform $\Fp^3$, compressed on both sides to internally distinct triples, has norm at most $6p^{-3/2}$. \end{theorem} \begin{proof} We first record the polynomial character identity needed for the Gram. For a monic squarefree polynomial $D$ of degree $2m$, put $\chi_D(f)=\chi(\operatorname{Res}(D,f))$ and $S_j(D)=\sum_{f\ {\rm monic},\,\deg f=j}\chi_D(f)$. On the finite \'etale algebra $\Fp[X]/D$, use the additive character $\psi_D(z)=\ee{\operatorname{res}(z/D)/p}$, where the residue is the coefficient of $X^{-1}$ at infinity. In the monomial basis $X^{2m-1},\ldots,X,1$, ordered by decreasing degree, the matrix of $(u,v)\mapsto\operatorname{res}(uv/D)$ has antidiagonal entries $1$ and zeros below that antidiagonal, so its determinant is $(-1)^{m(2m-1)}$. Factoring the algebra into fields and evaluating the quadratic Gauss sums gives \[ \sum_z\chi_D(z)\psi_D(bz)=p^m\chi_D(b). \] This holds also for nonunits $b$: a field factor then has a zero multiplicative-character sum. The annihilator of the polynomials of degree less than $k$ consists of those of degree less than $2m-k$. Summing the displayed Fourier identity over monic degree-$k$ polynomials, and then over the nonzero leading coefficient, yields \[ S_k(D)=p^{k-m}\left((p-1)\sum_{j=0}^{2m-k-2}S_j(D) -S_{2m-k-1}(D)\right),\qquad k<2m. \] For $j\ge2m$, $S_j(D)=0$ by periodicity modulo $D$: the sum over a complete residue system modulo $D$ vanishes. In particular, \[ \begin{array}{c|l} \deg D&\text{identities}\\ \hline 6&S_3=(p-1)(1+S_1)-S_2,\\ 4&S_2=p-1-S_1,\quad S_3=-p,\\ 2&S_1=-1,\quad S_2=S_3=0. \end{array} \] Write $G_d=B_d^*B_d$, let $r_g$ be the number of rational roots of $g$, put $R=\diag(r_g)$ and $L=G_1+J$, and introduce the features \[ C(a,g)=\one[g(a)=0],\qquad V(a,t;g)=\one[g(a)=0]\chi\bigl((g/(X-a))(t)\bigr). \] Here $a,t\in\Fp$ and $g\in\mathcal S_3$; in $V$, the quotient is understood only when $a$ is a root of $g$, and $V(a,t;g)=0$ otherwise. Set $T=C^*C+V^*V$ and $E=\sum_aV(a,a)^*V(a,a)$. The exact identity is \begin{equation}\label{eq:cubic-gram} G_3=p^3I+RL+LR-L-G_2-(p+1)T+E. \end{equation} Here is an entrywise verification, including nonsplit cubics. Fix $g,h$, put $U=\gcd(g,h)$, $D=gh/U^2$, and let $u$ be the number of $a\in\Fp$ such that $g(a)h(a)=0$. With $M_j=\sum_{\deg f=j,\ f\ {\rm monic}}\chi_g(f)\chi_h(f)$, the nonsquarefree quadratics and cubics are, respectively, $(X-a)^2$ and $(X-a)^2(X-b)$. Thus \[ (G_1)_{g,h}=M_1,\quad (G_2)_{g,h}=M_2-(p-u),\quad (G_3)_{g,h}=M_3-(p-u)M_1. \] For $g\ne h$, the generating series of the $M_j$ is that of the $S_j(D)$ multiplied by $\prod_{P\mid U}(1-\chi_D(P)z^{\deg P})$. If $U=1$, the degree-six identity gives zero correction in \eqref{eq:cubic-gram}. If $U=X-a$, put $\eta=\chi_D(X-a)$ and $\ell=1+S_1(D)$. Then \[ M_1=\ell-1-\eta,\quad M_2=p-(1+\eta)\ell+\eta,\quad M_3=-p(1+\eta)+\eta\ell, \] and $T_{g,h}=\ell$, $E_{g,h}=\eta$, giving the correction $-(p+1)\ell+\eta$. If $U=(X-a)(X-b)$, write $e_1=\chi_D(X-a)+\chi_D(X-b)$, $e_2=\chi_D(X-a)\chi_D(X-b)$. Then $(M_1,M_2,M_3)=(-1-e_1,e_1+e_2,-e_2)$ and $(T_{g,h},E_{g,h})=(-e_1,e_1)$, giving $(p+2)e_1$. If $U$ is an irreducible quadratic, the same calculation with $\eta=\chi_D(U)$ gives $(M_1,M_2,M_3)=(-1,-\eta,\eta)$ and $T_{g,h}=E_{g,h}=0$. On the diagonal, listing the degrees of the irreducible factors of $g$, the three factorization types give \[ \begin{array}{c|c|c|c|c|c} \text{type}&r_g&M_1&M_2&M_3&T_{g,g}\\ \hline 111&3&p-3&p^2-3p+3&p^3-3p^2+3p-1&3(p-1)\\ 12&1&p-1&p^2-p-1&p^3-p^2-p+1&p+1\\ 3&0&p&p^2&p^3-1&0 \end{array} \] and $E_{g,g}=r_g$. Substitution proves \eqref{eq:cubic-gram} in every case. Finally $0\preceq E\preceq T$. The synthesis identities \[ \sum_a C(a,g)=r_g,\qquad \sum_a\chi(t-a)V(a,t;g)=r_g\chi(g(t)) \] and Cauchy--Schwarz imply $C^*C\succeq p^{-1}RJR$ and $V^*V\succeq(p-1)^{-1}RG_1R$, hence $pT\succeq RLR$. Since $RLR-RL-LR+L=(R-I)L(R-I)\succeq0$, \eqref{eq:cubic-gram} gives $G_3\preceq p^3I$. Restriction to split cubics is a compression. Each split cubic has six ordered root triples; lifting both variables therefore multiplies the counting norm by $6$. Dividing by $p^3$ for uniform-cube measure proves the last assertion. \end{proof} As with the four-cycle bound, separate input and output restrictions are contractions. A jointly imposed missing-edge mask is a different operator and needs its own proof. The complete nine-edge case is used in the finite upper comparisons of \cref{prop:upper-soft-nine}. Other three-by-three subgraphs there retain matching, path or four-cycle witnesses. \space % End sections/15a_cubic_resultant \subsection{A two-variable character sum}\label{subsec:dl:H2} The second estimate concerns two labels whose characters are coupled through one factor $y-z$. For fixed $z$ the inner sum over $y$ is, up to an explicit correction, minus the trace of Frobenius at $z$ on a sheaf of rank $2\lfloor\deg f/2\rfloor$ attached to the family of curves $y^2=f(x)(x-z)$ (Katz--Sarnak). Twisting by the Kummer sheaf of $g$ keeps this sheaf geometrically irreducible of rank at least two. So the $H^2_c$ coinvariants vanish (\cref{lem:tame-trace-bound} below), i.e.\ no term of order $p^{3/2}$ occurs; the compactly supported cohomology lives in degree one, its dimension is the tame Euler characteristic, and Deligne's theorem bounds its Frobenius eigenvalues by $p$. This is square-root cancellation in both variables. For an integer $m\ge1$ put $\gamma(m)=m$ if $m$ is even and $\gamma(m)=m-1$ if $m$ is odd ($\gamma(m)=2\lfloor m/2\rfloor$; for $z$ distinct from the roots of $f$, this is twice the genus of the smooth projective model of $y^2=f(x)(x-z)$ with $\deg f=m$), and for integers $m\ge2$, $n\ge1$, $s\ge0$ \begin{equation}\label{eq:dl:B} \mathcal B(m,n,s)=\gamma(m)(m+n-s-1)+[m\text{ odd}]\big((n-1)r+mr^2\big) +m\big((m-2)r+r^2\big). \end{equation} \begin{theorem}[Two-variable character sum]\label{thm:dl:H2} Let $p$ be an odd prime, $r=p^{-1/2}$, $m\ge2$ and $n\ge1$ integers, $a_1,\dots,a_m\in\Fp$ distinct, $b_1,\dots,b_n\in\Fp$ distinct, $c,c'\in\Fp^\times$, \[ f(X)=c\prod_{i=1}^m(X-a_i),\qquad g(X)=c'\prod_{k=1}^n(X-b_k),\qquad s=\big|\{a_1,\dots,a_m\}\cap\{b_1,\dots,b_n\}\big| . \] Then $\Sigma=\sum_{y,z\in\Fp}\chi\big(f(y)\,g(z)\,(y-z)\big)$ satisfies $|\Sigma|\le p\,\mathcal B(m,n,s)$, and if $n\ge2$ also $|\Sigma|\le p\,\mathcal B(n,m,s)$. \end{theorem} \noindent The main term $\gamma(m)(m+n-s-1)$ is the dimension of a cohomology group of weight at most $2$; all other terms are the displayed multiples of $r$ and $r^2$ in \eqref{eq:dl:B}, with coefficients depending only on $m$ and $n$. (Only split polynomials occur in this paper. For even $m$ the same proof works for squarefree $f,g$ that do not split, with Weil's bound for general squarefree polynomials in place of \cref{thm:weil}; for odd $m$ the construction in \cref{lem:dl:sheaf} uses a root of $f$ in $\Fp$.) The proof rests on the following lemma, in which $U_f=\mathbb A^1_{\Fp}\setminus\{a_1,\dots,a_m\}$ and traces and Frobenius eigenvalues are regarded as complex numbers through the isomorphism of $\overline{\mathbb Q}_\ell$ with $\C$ fixed in \cref{subsec:external:sheaves}. Its parts (v) and (vi) are used only in \cref{subsec:moving-root}. \begin{lemma}[The sheaf of the family $y^2=f(x)(x-z)$]\label{lem:dl:sheaf} Let $f=\prod_{i=1}^m(X-a_i)$ with $m\ge2$ and distinct $a_i\in\Fp$ \textup(so $f$ is monic\textup), and put \[ \tau_f(z)=\frac1p\Big(\sum_{y\in\Fp}\chi\big(f(y)(y-z)\big)+[m\text{ odd}]\Big) \qquad(z\in\Fp). \] If $m$ is odd, fix a root $a$ of $f$ \textup(any root may be chosen\textup). The construction below, applied to this fixed $a$, gives a lisse $\overline{\mathbb Q}_\ell$-sheaf $\mathcal F'$ on $U_f$ such that: \begin{enumerate}[label=\textup{(\roman*)}] \item $\mathcal F'$ has rank $\gamma(m)$ and is pure of weight $1$; \item $\mathcal F'$ is geometrically irreducible; \item $\mathcal F'$ is tame at every point of $\mathbb P^1\setminus U_f=\{a_1,\dots,a_m,\infty\}$; \item $p\,\tau_f(z)=-\mathrm{Tr}(\mathrm{Frob}_z\mid\mathcal F')$ for every $z\in U_f(\Fp)$; \item there is a perfect alternating pairing $\mathcal F'\otimes\mathcal F'\to\overline{\mathbb Q}_\ell(-1)$ of lisse sheaves on $U_f$; \item for every root $a_i$ of $f$ if $m$ is even, and for every root $a_i\ne a$ if $m$ is odd, the inertia group at $a_i$ acts on $\mathcal F'$ through unipotent automorphisms, not all trivial. \end{enumerate} \end{lemma} \begin{proof} \emph{$m$ even.} Let $\mathcal F'=\mathcal F_f$ be the sheaf of \cref{thm:prelim:ks} with $k=\Fp$ and $h=f$, a polynomial of degree $m=2\cdot\frac m2$, $\frac m2\ge1$, with $m$ distinct roots; then $U_h=U_f$. Parts (i), (ii), (iii) and (v) are \cref{thm:prelim:ks}(i), (iii), (ii) and (v), and \cref{thm:prelim:ks}(iv) with $E=\Fp$, $t=z$, gives $-\mathrm{Tr}(\mathrm{Frob}_z\mid\mathcal F_f)=\sum_x\chi((x-z)f(x))=p\,\tau_f(z)$. For (vi), $\mathcal F_f$ is tame at $a_i$ (\cref{thm:prelim:ks}(ii)), so its local monodromy there factors through the pro-cyclic tame quotient (\ref{it:prelim:E3}), and the inertia image is the closure of the group generated by the element $u$ of \cref{thm:prelim:ks}(vi). As $(u-1)^2=0$, the powers $u^k=1+k(u-1)$ are unipotent, hence so is every element $1+c(u-1)$ of the closure, and $u\ne1$. \emph{$m$ odd.} Then $m\ge3$. Put $f_1=f/(X-a)$, so $\deg f_1=m-1\ge2$ is even and $f_1(a)\ne0$, and \[ f_1^\sharp(X)=X^{m-1}f_1\big(a+X^{-1}\big)=\prod_{a_i\ne a}\big(1+(a-a_i)X\big). \] $f_1^\sharp$ has degree $m-1$ (leading coefficient $f_1(a)\ne0$), the $m-1$ distinct roots $1/(a_i-a)\in\Fp^\times$ ($a_i\ne a$), and $f_1^\sharp(0)=1$. Let $\varphi_a:\mathbb A^1\setminus\{a\}\to\mathbb A^1\setminus\{0\}$, $\varphi_a(z)=1/(z-a)$, an isomorphism of $\Fp$-schemes that extends to the automorphism $z\mapsto1/(z-a)$ of $\mathbb P^1$ (with $a\mapsto\infty$, $\infty\mapsto0$). It maps $U_f$ onto $W=\mathbb A^1\setminus(\{0\}\cup Z(f_1^\sharp))$, since $\varphi_a(a_i)=1/(a_i-a)$ for $a_i\ne a$. Let $\mathcal F_{f_1^\sharp}$ be the sheaf of \cref{thm:prelim:ks} with $k=\Fp$, $h=f_1^\sharp$ (degree $m-1=2\cdot\frac{m-1}2$, $\frac{m-1}2\ge1$, distinct roots), lisse on $U_{f_1^\sharp}=\mathbb A^1\setminus Z(f_1^\sharp)\supseteq W$, and let $\mathcal L=\mathcal L_{\chi(a-z)}$ be the Kummer sheaf \ref{it:prelim:E4} of the polynomial $a-z$, lisse on $\mathbb A^1\setminus\{a\}\supseteq U_f$. Put \[ \mathcal F'=\varphi_a^*\big(\mathcal F_{f_1^\sharp}|_W\big)\otimes\mathcal L|_{U_f}. \] \emph{Transport of (i)--(iii) and (v).} Restriction to a dense open, pull-back by an isomorphism, and tensoring with a rank-one sheaf preserve geometric irreducibility (\ref{it:prelim:E1}). Thus \cref{thm:prelim:ks}(i),(iii) and \ref{it:prelim:E2}, \ref{it:prelim:E4} give rank $m-1=\gamma(m)$, purity of weight $1$ and geometric irreducibility for $\mathcal F'$. For tameness, the automorphism $\varphi_a$ sends the roots other than $a$ to $Z(f_1^\sharp)$, sends $a$ to infinity, and sends infinity to $0$. The original sheaf is tame at $Z(f_1^\sharp)$ and infinity and lisse at $0$; hence its restriction to $W$ and pull-back are tame at every missing point. The Kummer sheaf is tame there too, so their tensor product is tame (\ref{it:prelim:E3}). Finally, $\mathcal L\otimes\mathcal L$ is the constant sheaf, since its monodromy character has order dividing two (\ref{it:prelim:E4}). Pulling back the pairing of \cref{thm:prelim:ks}(v) and using this trivialization gives the perfect alternating pairing for $\mathcal F'$, with the same target $\overline{\mathbb Q}_\ell(-1)$. This proves (i)--(iii) and (v). (iv) Let $z\in U_f(\Fp)$ and $w=\varphi_a(z)=1/(z-a)$, so $-w=1/(a-z)$. By \ref{it:prelim:E1}, \ref{it:prelim:E4} and \cref{thm:prelim:ks}(iv) with $E=\Fp$, \[ -\mathrm{Tr}(\mathrm{Frob}_z\mid\mathcal F') =-\chi(a-z)\,\mathrm{Tr}(\mathrm{Frob}_w\mid\mathcal F_{f_1^\sharp}) =\sum_{x'\in\Fp}\chi\big((a-z)(x'-w)f_1^\sharp(x')\big). \] On the other hand, the term $y=a$ of $\sum_y\chi(f(y)(y-z))$ vanishes ($f(a)=0$), and $y\mapsto x'=1/(y-a)$ is a bijection of $\Fp\setminus\{a\}$ onto $\Fp^\times$ with $y=a+1/x'$. For such $y$, $f(y)=x'^{-1}f_1(a+1/x')=x'^{-m}f_1^\sharp(x')$ and $y-z=x'^{-1}\big((a-z)x'+1\big)=x'^{-1}(a-z)(x'-w)$, so $f(y)(y-z)=x'^{-(m+1)}(a-z)(x'-w)f_1^\sharp(x')$ with $m+1$ even. Hence \begin{align*} \sum_y\chi\big(f(y)(y-z)\big) &=\sum_{x'\ne0}\chi\big((a-z)(x'-w)f_1^\sharp(x')\big)\\ &=-\mathrm{Tr}(\mathrm{Frob}_z\mid\mathcal F')-\chi\big((a-z)(-w)f_1^\sharp(0)\big) =-\mathrm{Tr}(\mathrm{Frob}_z\mid\mathcal F')-1, \end{align*} since $(a-z)(-w)=1$ and $f_1^\sharp(0)=1$; that is, $p\,\tau_f(z)=-\mathrm{Tr}(\mathrm{Frob}_z\mid\mathcal F')$. (vi) Let $a_i\ne a$ be a root of $f$. The automorphism of $\mathbb P^1$ extending $\varphi_a$ maps $a_i$ to the root $1/(a_i-a)$ of $f_1^\sharp$ and, by \ref{it:prelim:E3}, the inertia groups at $a_i$ onto those at $1/(a_i-a)$; so the inertia at $a_i$ acts on $\varphi_a^*(\mathcal F_{f_1^\sharp}|_W)$ as the inertia at $1/(a_i-a)$ acts on $\mathcal F_{f_1^\sharp}|_W$, that is, as it acts on $\mathcal F_{f_1^\sharp}$ (restriction to the dense open $W$ keeps the inertia groups and the local monodromy at this point, \ref{it:prelim:E3}). This is as stated in (vi), by the argument of the even case applied to $\mathcal F_{f_1^\sharp}$ (\cref{thm:prelim:ks}(ii), (vi)). The sheaf $\mathcal L$ is lisse at $a_i$, so the inertia at $a_i$ acts trivially on it (\ref{it:prelim:E3}), and the tensor product has the same local monodromy at $a_i$ as $\varphi_a^*\mathcal F_{f_1^\sharp}$. \end{proof} For odd $m$ we have $m\ge3$, so the root $a$ can be chosen different from any given root of $f$. Thus every root of $f$ is, for some allowed choice of the root $a$ in the construction of $\mathcal F'$, a point at which the inertia acts through nontrivial unipotent automorphisms; this is how part (vi) is used in \cref{lem:moving-root-moments}. The cohomological step used below is the same for one trace and for a product of two traces. Once the geometric coinvariants vanish, only the rank, the weight and the number of punctures enter the bound. \begin{lemma}[Tame trace bound]\label{lem:tame-trace-bound} Let $B\subseteq\Fp$ have $m\ge1$ elements, let $U=\mathbb A^1_{\Fp}\setminus B$, and let $\mathcal G$ be a lisse sheaf on $U$ of rank $R$, mixed of weights at most $w$, and tame at every point of $B\cup\{\infty\}$. Suppose its generic stalk $V$ has zero coinvariants under $\pi_1^{\rm geom}(U)$. Then \[ \dim H^1_c(U\otimes\bar\F_p,\mathcal G)=R(m-1),\qquad \left|\sum_{x\in U(\Fp)}\mathrm{Tr}(\mathrm{Frob}_x\mid\mathcal G)\right| \le R(m-1)p^{(w+1)/2}. \] In particular the coinvariant hypothesis holds if $\mathcal G$ is geometrically irreducible of rank at least two. \end{lemma} \begin{proof} By \cref{thm:prelim:curves}, compactly supported cohomology vanishes outside degrees one and two, and $H^2_c\cong V_{\pi_1^{\rm geom}(U)}(-1)=0$. Tameness at all $m+1$ missing points makes every Swan conductor zero, so \cref{thm:prelim:gos} gives $-\dim H^1_c=R(2-(m+1))$. By \cref{thm:prelim:lefschetz}, the trace sum is $-\mathrm{Tr}(\mathrm{Frob}_p\mid H^1_c)$, and every eigenvalue in this trace has modulus at most $p^{(w+1)/2}$ by \cref{thm:prelim:weights}. Finally, the span of the vectors $gv-v$ is invariant. For an irreducible representation it is zero or all of $V$; the first possibility makes the action trivial, which is incompatible with irreducibility in rank at least two. Thus the coinvariants vanish in the stated special case. \end{proof} \begin{proof}[Proof of \cref{thm:dl:H2}] \emph{Step 0 (normalization).} Replacing $f,g$ by $f/c$, $g/c'$ multiplies $\Sigma$ by $\chi(cc')=\pm1$, and $\mathcal B$ does not depend on $c,c'$; so we may assume $f$ and $g$ monic. Write $Z(f)=\{a_i\}$, $Z(g)=\{b_k\}$, so $|Z(f)\cup Z(g)|=m+n-s$. \emph{Step 1 (the three parts).} $\Sigma=\sum_{z\in\Fp}\chi(g(z))\sum_y\chi\big(f(y)(y-z)\big)$. For $z=a_j\in Z(f)$, $f(y)(y-a_j)=(y-a_j)^2f_j(y)$ with $f_j=\prod_{i\ne j}(X-a_i)$, $\deg f_j=m-1\ge1$, so $\chi(f(y)(y-a_j))=\chi(f_j(y))$ for $y\ne a_j$ and $0$ for $y=a_j$; by \cref{thm:weil}, $|\sum_y\chi(f(y)(y-a_j))|\le|\sum_y\chi(f_j(y))|+1\le(m-2)\sqrt p+1$. For $z\notin Z(f)$, \cref{lem:dl:sheaf}(iv) gives $\sum_y\chi(f(y)(y-z))=p\,\tau_f(z)-[m\text{ odd}] =-\mathrm{Tr}(\mathrm{Frob}_z\mid\mathcal F')-[m\text{ odd}]$. Hence \begin{multline*} \Sigma=-\sum_{z\in U_f(\Fp)}\chi(g(z))\,\mathrm{Tr}(\mathrm{Frob}_z\mid\mathcal F') \ -\ [m\text{ odd}]\sum_{z\in U_f(\Fp)}\chi(g(z))\\ +\ \sum_{z\in Z(f)}\chi(g(z))\sum_y\chi\big(f(y)(y-z)\big). \end{multline*} The last part is at most $m\big((m-2)\sqrt p+1\big)$ in modulus. The middle sum differs from $\sum_{z\in\Fp}\chi(g(z))$ by at most $m$ terms of modulus at most $1$, and $|\sum_z\chi(g(z))|\le(n-1)\sqrt p$ by \cref{thm:weil}; so the middle part is at most $(n-1)\sqrt p+m$ (and occurs only for odd $m$). \emph{Step 2 (the sheaf $\mathcal G$).} Let $U'=U_f\setminus Z(g)=\mathbb A^1\setminus(Z(f)\cup Z(g))$, $\mathcal L_{\chi(g)}$ the Kummer sheaf of $g$ of \ref{it:prelim:E4}, lisse on $\mathbb A^1\setminus Z(g)\supseteq U'$, and $\mathcal G=\mathcal L_{\chi(g)}|_{U'}\otimes\mathcal F'|_{U'}$. As $\chi(g(z))=0$ for $z\in Z(g)$, the first part is $-\sum_{z\in U'(\Fp)}\mathrm{Tr}(\mathrm{Frob}_z\mid\mathcal G)$ by \ref{it:prelim:E1} and \ref{it:prelim:E4}. $\mathcal G$ is lisse of rank $\gamma(m)\ge2$ and pure of weight $1$ (\cref{lem:dl:sheaf}(i), \ref{it:prelim:E2}); it is geometrically irreducible (\cref{lem:dl:sheaf}(ii): the restriction to the dense open $U'$ and the tensor product with a rank-one sheaf preserve this, \ref{it:prelim:E1}); and it is tame at every point of $\mathbb P^1\setminus U'=Z(f)\cup Z(g)\cup\{\infty\}$ by \ref{it:prelim:E3} (restriction to a dense open keeps tameness, a sheaf is tame at a point where it is lisse, and tensor products of tame sheaves are tame): $\mathcal F'$ is tame at $Z(f)\cup\{\infty\}$ (\cref{lem:dl:sheaf}(iii)) and lisse at the points of $Z(g)\setminus Z(f)\subseteq U_f$, and $\mathcal L_{\chi(g)}$ is tame at the points of $Z(g)\cup\{\infty\}$ (\ref{it:prelim:E4}) and lisse at those of $Z(f)\setminus Z(g)$. \emph{Step 3 (cohomology).} The sheaf of Step~2 satisfies \cref{lem:tame-trace-bound}: its rank is $\gamma(m)\ge2$, its weight is $1$, it is geometrically irreducible, and it is tame at all $m+n-s+1$ missing points, including infinity. Therefore \[ \left|\sum_{z\in U'(\Fp)}\mathrm{Tr}(\mathrm{Frob}_z\mid\mathcal G)\right| \le\gamma(m)(m+n-s-1)p. \] The trace sum is $-p\sum_{z\in U'(\Fp)}\chi(g(z))\tau_f(z)$, a rational integer by \cref{lem:dl:sheaf}(iv), so the bound is independent of the identification of $\overline{\mathbb Q}_\ell$ with $\C$. It bounds the first part of Step~1. \emph{Step 4 (conclusion).} Adding the three parts, \[ |\Sigma|\le\gamma(m)(m+n-s-1)p+[m\text{ odd}]\big((n-1)\sqrt p+m\big) +m\big((m-2)\sqrt p+1\big)=p\,\mathcal B(m,n,s). \] Finally, $\Sigma=\chi(-1)\sum_{z,y}\chi\big(g(z)f(y)(z-y)\big)$ is, up to sign, the sum of the theorem for the pair $(g,f)$; if $n\ge2$ the bound just proved applies to it and gives $|\Sigma|\le p\,\mathcal B(n,m,s)$. \end{proof} \begin{remark}[Sharpness and the coefficients of $\mathcal B$]\label{rem:dl:H2-sharp} (i) The main term is nearly attained (numerically): for $f$ proportional to $g$ of degree two ($m=n=s=2$) the group $H^1_c$ has dimension $2$, and exact computations for primes up to $9\cdot10^4$ give $|\Sigma|/(p\mathcal B)$ up to $0.998$ (numerical, not used). The consistency test of \cref{thm:dl:H2} against exact double sums is described in \cref{rem:cert:deligne-tests}; it is not an input of any proof. (ii) As a polynomial in $r$, $\mathcal B(m,n,0)=C_0+C_1r+C_2r^2$ with $(C_0,C_1,C_2)=\big(\gamma(m)(m+n-1),\ m(m-2)+[m\text{ odd}](n-1),\ m(1+[m\text{ odd}])\big)$; these are the coefficient triples with which the completion variance (\cref{lem:push:localvariance}) uses the theorem. (iii) $\mathcal B(m,n,s)$ is nonincreasing in $s$ and nondecreasing in $n$. Since $\mathcal B(2,4,0)=10+2r^2$, $\mathcal B(3,4,0)=12+6r+6r^2$ and $\mathcal B(4,4,0)=28+8r+4r^2$, and $r\le1/\sqrt3$, we get $\mathcal B(m,n,s)\le\mathcal B(4,4,0)<40$ for $2\le m\le4$, $1\le n\le4$, $s\ge0$ and every odd prime; the product rows use this. \end{remark} \subsection{Trace functions with one free label}\label{subsec:moving-root} At a root cut of the upper range the star part of the cut kernel is an average over the label $z$ of an integrated centre of a product of characters $\chi(z-x_j)$ over the leaves $j$ of the star. Fixing all half labels except the label $x_i$ of one leaf turns such a star into an affine function of a single \emph{moving-root trace} $\tau_S(x_i)$, whose fixed roots $S$ are the labels of the other leaves (\cref{lem:star-trace}). The second moments of combinations of these traces against the conditional law of $x_i$ (a uniform law on an allowed set, whose density is a product of characters with the neighbouring labels as roots) are governed by the almost-orthogonality of traces with distinct root sets against character weights (\cref{lem:moving-root-moments}). This is a statement about sheaves: distinct root sets give non-isomorphic sheaves, even after a quadratic twist, because their local monodromy at a root in the symmetric difference differs. First moments satisfy \eqref{eq:advance:rank-first}, with its factor $r^2$ in place of the pointwise factor $r$ in $|\tau_S|\le sr$ (\cref{lem:moving-root-trace}(b)), and they make pivot groups almost orthogonal without any independence assumption (\cref{prop:advance:ordered-star}). For a graph law the same conditioning, with the conditional means bounded through \cref{thm:dl:H2} and the diagonal terms through densities, bounds star marginals with arbitrary real coefficients (\cref{lem:wt:stars}). The subsection ends with the exact mean of the complete star (\cref{lem:star-mean}). \subsubsection{Trace functions and stars}\label{subsec:advance:conditional-star} For a set $S\subseteq\Fp$ of $s=|S|\ge2$ distinct elements put $f_S=\prod_{c\in S}(X-c)$ and \begin{equation}\label{eq:moving-root-tau} \tau_S(x)=\frac1p\Big(\sum_{z\in\Fp}\chi\Big((z-x)\prod_{c\in S}(z-c)\Big) +\one_{|S|\ \rm odd}\Big)\qquad(x\in\Fp). \end{equation} Thus $\tau_S=\tau_{f_S}$ in the notation of \cref{lem:dl:sheaf}. We write $\mathcal F_S$ for a sheaf on $\mathbb A^1\setminus S$ given by \cref{lem:dl:sheaf} for $f=f_S$ (for odd $s$ with some choice of the root $a$), and $h(s)=2\lfloor s/2\rfloor=\gamma(s)$ for its rank. The correction $\one_{|S|\ \rm odd}$ accounts for the points at infinity: for $x\notin S$ and odd $s$ the polynomial $(z-x)f_S(z)$ is squarefree of even degree with leading coefficient one, so the smooth projective curve $y^2=(z-x)f_S(z)$ has two rational points at infinity, which the affine sum misses. With the correction, $p\,\tau_S(x)$ is, for every $s$ and $x\notin S$, minus the trace of Frobenius on the first cohomology of that curve. \begin{lemma}[Moving-root traces]\label{lem:moving-root-trace} Let $S\subseteq\Fp$ with $|S|=s\ge2$. \begin{enumerate}[label=\textup{(\alph*)}] \item $\tau_S$ is real, and $\tau_S(x)=-p^{-1}\,\mathrm{Tr}(\mathrm{Frob}_x\mid\mathcal F_S)$ for $x\notin S$. \item $|\tau_S(x)|\le h(s)r$ for $x\notin S$, and $|\tau_S(x)|\le\big((s-2)\sqrt p+2\big)/p\le sr$ for $x\in S$. In particular $|\tau_S|\le sr$ on $\Fp$. \end{enumerate} \end{lemma} \begin{proof} (a) is \cref{lem:dl:sheaf}(iv). (b) For $x\notin S$, $\mathcal F_S$ has rank $h(s)$ and is pure of weight $1$ (\cref{lem:dl:sheaf}(i)), so each Frobenius eigenvalue at $x$ has modulus $\sqrt p$, and $|p\,\tau_S(x)|\le h(s)\sqrt p$. For $x\in S$, $(z-x)f_S(z)=(z-x)^2f_{S\setminus\{x\}}(z)$; the term $z=x$ vanishes, and for $z\ne x$ the summand is $\chi(f_{S\setminus\{x\}}(z))$. Hence $p\,\tau_S(x)=\sum_z\chi(f_{S\setminus\{x\}}(z))-\chi(f_{S\setminus\{x\}}(x)) +\one_{s\ \rm odd}$. The first sum has modulus at most $(s-2)\sqrt p$ by \cref{thm:weil} (a product of $s-1\ge1$ distinct linear factors), and the two other terms have modulus at most one; finally $2\le2\sqrt p$. \end{proof} \begin{lemma}[Star-trace dictionary]\label{lem:star-trace} Let $x:U\to\Fp$ be injective, $T\subseteq U$ nonempty, and $w_T(x)=\E_z\prod_{j\in T}\chi(z-x_j)$. Then $w_T(x)=0$ if $|T|=1$, $w_T(x)=-1/p$ if $|T|=2$, and for $|T|\ge3$ and every $i\in T$, \[ w_T(x)=\tau_{x(T\setminus\{i\})}(x_i)-\frac{\one_{|T|\ \rm even}}p,\qquad x(T\setminus\{i\})=\{x_j:j\in T\setminus\{i\}\}. \] For signs $\varsigma_j\in\{\pm1\}$, $\E_z\prod_{j\in T}\chi(\varsigma_j(z-x_j))=\big(\prod_{j\in T}\chi(\varsigma_j)\big)w_T(x)$. \end{lemma} \begin{proof} For $|T|=1$, $\sum_z\chi(z-x_j)=0$. For $|T|=2$, $\sum_z\chi((z-x_j)(z-x_{j'}))=-1$ by \eqref{eq:two-root}, as $x_j\ne x_{j'}$. For $|T|\ge3$ and $i\in T$, $\prod_{j\in T}(z-x_j)=(z-x_i)\prod_{c\in S}(z-c)$ with $S=x(T\setminus\{i\})$, a set of $|T|-1\ge2$ distinct elements, and $|S|$ is odd iff $|T|$ is even; so $w_T(x)=\tau_S(x_i)-\one_{|T|\ \rm even}/p$ by \eqref{eq:moving-root-tau}. The signs factor out since $\chi$ is multiplicative. \end{proof} \paragraph{The star function.} Consider spectral data (\cref{def:spec:data}) with half vertex set $U^+$, half graph $G^+$, cross signs $\varsigma_{jk}$ and $N(k)=\{j\in U^+:\varsigma_{jk}\ne0\}$. The column stars of the cut kernel centred at $k$ have kernels $\prod_{j\in T}\chi(\varsigma_{jk}(x'_k-x_j))$, $\emptyset\ne T\subseteq N(k)$; averaging the centre label $z$ uniformly on $\Fp$ gives the \emph{integrated-centre star function} \begin{equation}\label{eq:star-function} h_\star(x)=\sum_{k\in U^+}\Big(\E_z\prod_{j\in N(k)}\big(1+\chi(\varsigma_{jk}(z-x_j))\big)-1\Big) =\sum_{\emptyset\ne T\subseteq U^+}a_Tw_T(x),\qquad a_T=\sum_{k:\,T\subseteq N(k)}\ \prod_{j\in T}\chi(\varsigma_{jk}). \end{equation} We fix this sign convention: the signs $\chi(\varsigma_{jk})$ belong to the centre $k$, and no factor $\chi(-1)^{|T|}$ appears. (Writing the characters as $\chi(x_j-z)$ multiplies $a_T$ by $\chi(-1)^{|T|}$; the bounds below use $|a_T|$ for odd $|T|$, and for even $|T|$ the factor is one, so they do not depend on the convention.) By \cref{lem:star-trace}, on injective labellings $h_\star$ is a constant plus a linear combination of the traces $\tau_{x(T\setminus\{i\})}(x_i)$, $|T|\ge3$, for any choice of $i\in T$. The row stars map constants to constants (\cref{lem:spec:stars}(b)), so they disappear under projection off constants. \subsubsection{Means and mean squares of the traces \texorpdfstring{$\tau_S$}{tau\_S}}\label{subsec:moving-root-moments} For a finite set $A\subseteq\Fp$ put $\chi_A(x)=\prod_{a\in A}\chi(x-a)$, the squarefree character factor with root set $A$ ($\chi_\emptyset=1$). \begin{lemma}[Moving-root moments]\label{lem:moving-root-moments} Let $p$ be an odd prime, $r=p^{-1/2}$, $h(s)=2\lfloor s/2\rfloor$, and let $S,T,A\subseteq\Fp$ with $|S|=s\ge2$, $|T|=t\ge2$ and $|A|=u\ge0$; the three sets may overlap arbitrarily. Then \begin{align} \Big|\E_x\chi_A\tau_S\tau_T-p^{-1}\one_{S=T,\ A=\emptyset}\Big| &\le r^3\Big[(s+t+u-1)h(s)h(t)+1+r(s+t+u)st\Big], \label{eq:advance:rank-second}\\ \big|\E_x\chi_A\tau_S\big| &\le r^2\Big[(s+u-1)h(s)+r(s+u)s\Big]. \label{eq:advance:rank-first} \end{align} \end{lemma} \begin{proof} Let $U=\mathbb A^1\setminus(S\cup T\cup A)$ and $\pi=\pi_1^{\rm geom}(U)$. We use sheaves $\mathcal F_S$, $\mathcal F_T$ of \cref{lem:dl:sheaf} for $f_S$, $f_T$, restricted to $U$, with $\mathcal F_T=\mathcal F_S$ if $T=S$; when $s$ or $t$ is odd, the root $a$ of that construction (the \emph{inversion root}) is chosen in Step~3 (\cref{lem:dl:sheaf} and \cref{lem:moving-root-trace} hold for every choice). Let $\mathcal L$ be the Kummer sheaf of $g_A=\prod_{a\in A}(X-a)$ restricted to $U$ (the constant sheaf if $A=\emptyset$), with monodromy character $\lambda$; so $\mathrm{Tr}(\mathrm{Frob}_x\mid\mathcal L)=\chi_A(x)$ for $x\in U(\Fp)$ (\ref{it:prelim:E4}). Put $\mathcal G=\mathcal F_S\otimes\mathcal F_T\otimes\mathcal L$, and write $V_S$, $V_T$ for the generic stalks of $\mathcal F_S$, $\mathcal F_T$ as representations $\rho_S$, $\rho_T$ of $\pi$. \emph{Step 1 (traces and omitted points).} For every $x\in U(\Fp)$, \cref{lem:moving-root-trace}(a) and \ref{it:prelim:E1} give \[ \chi_A(x)\tau_S(x)\tau_T(x)=p^{-2}\,\mathrm{Tr}(\mathrm{Frob}_x\mid\mathcal G). \] For $x\in A$, $\chi_A(x)=0$. The remaining points $x\in(S\cup T)\setminus A$ number at most $s+t$, and there $|\chi_A\tau_S\tau_T|\le st\,r^2$ by \cref{lem:moving-root-trace}(b). Hence \begin{equation}\label{eq:moving-root-omitted} \Big|\E_x\chi_A\tau_S\tau_T-p^{-3}\sum_{x\in U(\Fp)} \mathrm{Tr}(\mathrm{Frob}_x\mid\mathcal G)\Big| \le p^{-1}(s+t)st\,r^2\le r^4(s+t+u)st . \end{equation} \emph{Step 2 (the top cohomology).} $\mathcal G$ is lisse on $U$ of rank $h(s)h(t)$, pure of weight $2$ (\ref{it:prelim:E2}; $\mathcal L$ has weight $0$), and tame at every point of $\mathbb P^1\setminus U$ (\cref{lem:dl:sheaf}(iii), \ref{it:prelim:E3}, \ref{it:prelim:E4}). By \cref{thm:prelim:lefschetz,thm:prelim:curves}, \[ \sum_{x\in U(\Fp)}\mathrm{Tr}(\mathrm{Frob}_x\mid\mathcal G) =\mathrm{Tr}(\mathrm{Frob}_p\mid H^2_c)-\mathrm{Tr}(\mathrm{Frob}_p\mid H^1_c), \qquad H^i_c=H^i_c(U\otimes\bar\F_p,\mathcal G), \] and $H^2_c\cong(V_S\otimes V_T\otimes\lambda)_\pi(-1)$. The dual of the space of coinvariants is the space of $\pi$-invariant linear forms on $V_S\otimes V_T\otimes\lambda$, that is the $\pi$-invariants of $V_S^\vee\otimes V_T^\vee\otimes\lambda^{-1}$. The pairing of \cref{lem:dl:sheaf}(v) identifies $V_S$ with $V_S^\vee$ as $\pi$-representations ($\pi$ acts trivially on $\overline{\mathbb Q}_\ell(-1)$), and $\lambda^{-1}=\lambda$; so this space is $(V_S\otimes V_T^\vee\otimes\lambda)^\pi =\mathrm{Hom}_\pi(V_T,V_S\otimes\lambda)$. The representations $V_T$ and $V_S\otimes\lambda$ are irreducible (\cref{lem:dl:sheaf}(ii); restriction to a dense open and twisting by a rank-one sheaf preserve geometric irreducibility, \ref{it:prelim:E1}). By Schur's lemma, $\dim H^2_c=1$ if $V_S\cong V_T\otimes\lambda$ (equivalently $V_T\cong V_S\otimes\lambda$, as $\lambda^2=1$), and $H^2_c=0$ otherwise. \emph{Step 3 (local monodromy: $H^2_c=0$ unless $S=T$ and $A=\emptyset$).} For a finite point $c\in\mathbb P^1\setminus U$ let $I_c\subseteq\pi$ be an inertia group at $c$ (\ref{it:prelim:E3}). A sheaf lisse at $c$ has trivial inertia image there, and a rank-one sheaf has scalar inertia image. Restriction to the dense open $U$ keeps the local monodromy at $c$ (\ref{it:prelim:E3}), so \cref{lem:dl:sheaf}(vi) for $\mathcal F_S$ on $\mathbb A^1\setminus S$ holds for its restriction to $U$. For every $c\in A$ the character $\lambda$ is nontrivial on $I_c$: $c$ is a simple root of $g_A$, so the double covering $w^2=g_A(z)$ is ramified at $c$ and the local monodromy of $\mathcal L$ at $c$ is the character of order $2$ of $I_c$ (the case of odd multiplicity in \ref{it:prelim:E4}, and \ref{it:prelim:E3} for the restriction to $U$). Suppose $S\ne T$. Choose $c_0\in S\triangle T$; exchanging $S$ and $T$ if necessary, $c_0\in S\setminus T$. If $s$ is odd, construct $\mathcal F_S$ with an inversion root different from $c_0$. By \cref{lem:dl:sheaf}(vi), $\rho_S(I_{c_0})$ is not contained in the scalars (a unipotent scalar is the identity), while $\mathcal F_T$ is lisse at $c_0$ and $\mathcal L$ has rank one, so $\rho_T\otimes\lambda$ maps $I_{c_0}$ into the scalars. Hence $V_S\not\cong V_T\otimes\lambda$. Suppose $S=T$ and $A\ne\emptyset$, so that $\mathcal F_T=\mathcal F_S$. Choose $c_0\in A$ and, if $c_0\in S$ and $s$ is odd, construct $\mathcal F_S$ with an inversion root different from $c_0$. Take $g\in I_{c_0}$ with $\lambda(g)=-1$. If $c_0\notin S$, then $\rho_S(g)=1$ ($\mathcal F_S$ is lisse at $c_0$), while $(\rho_S\otimes\lambda)(g)=-1$. If $c_0\in S$, then $\rho_S(g)$ is unipotent by \cref{lem:dl:sheaf}(vi), so all its eigenvalues are $1$, while all eigenvalues of $(\rho_S\otimes\lambda)(g)=-\rho_S(g)$ are $-1$. In both cases $\rho_S(g)$ and $(\rho_S\otimes\lambda)(g)$ are not conjugate, so $V_S\not\cong V_S\otimes\lambda$. Thus $H^2_c=0$ unless $S=T$ and $A=\emptyset$. (In that case $\lambda=1$, $V_T=V_S$ and $H^2_c$ is one-dimensional; the case is computed directly in Step~4.) \emph{Step 4 (the diagonal case).} Let $S=T$ and $A=\emptyset$. Write $p\,\tau_S(x)=Y(x)+\one_{s\ \rm odd}$ with $Y(x)=\sum_z\chi(z-x)\chi(f_S(z))$. Then $\sum_xY(x)=0$, since $\sum_x\chi(z-x)=0$. By the two-root identity \eqref{eq:two-root}, $\sum_x\chi\big((z-x)(z'-x)\big)$ is $p-1$ if $z=z'$ and $-1$ otherwise, and $\chi(f_S(z))^2=\one_{z\notin S}$; so \begin{gather*} \sum_xY(x)^2=p(p-s)-\Big(\sum_z\chi(f_S(z))\Big)^2,\\ \E_x\tau_S^2=\frac{\sum_xY(x)^2+p\one_{s\ \rm odd}}{p^3} =\frac1p-\frac{h(s)}{p^2}-\frac1{p^3}\Big(\sum_z\chi(f_S(z))\Big)^2, \end{gather*} as $s-\one_{s\ \rm odd}=h(s)$. By \cref{thm:weil}(a) the last sum has modulus at most $(s-1)\sqrt p$, so $|\E_x\tau_S^2-p^{-1}|\le\big(h(s)+(s-1)^2\big)r^4\le2s^3r^4$, which is the last term of \eqref{eq:advance:rank-second} for $T=S$, $u=0$. Conceptually, the main term $1/p$ is the one invariant of $\mathcal F_S\otimes\mathcal F_S$, the pairing of \cref{lem:dl:sheaf}(v), on which Frobenius acts by $p$; the computation does not use this. The sheaves are needed for distinct root sets and nontrivial weights. \emph{Step 5 (dimension and weights).} If $S\ne T$ or $A\ne\emptyset$, Steps~2 and~3 show that the geometric coinvariants of $\mathcal G$ vanish. Its rank is $h(s)h(t)$, its weight is $2$, and it is tame at the $|S\cup T\cup A|+1$ missing points, including infinity. Thus \cref{lem:tame-trace-bound} gives \[ \Big|\sum_{x\in U(\Fp)}\mathrm{Tr}(\mathrm{Frob}_x\mid\mathcal G)\Big| \le h(s)h(t)(|S\cup T\cup A|-1)p^{3/2} \le(s+t+u-1)h(s)h(t)p^{3/2}. \] Dividing by $p^3$ and adding \eqref{eq:moving-root-omitted} gives \eqref{eq:advance:rank-second}, with the term $1$ of the bracket to spare (it allows for the invariant of the diagonal case). \emph{Step 6 (the first moment).} Let $U'=\mathbb A^1\setminus(S\cup A)$ and $\mathcal G'=\mathcal F_S\otimes\mathcal L'$ on $U'$, with $\mathcal L'$ the Kummer sheaf of $g_A$ on $U'$. $\mathcal G'$ is lisse of rank $h(s)\ge2$, pure of weight $1$, tame, and geometrically irreducible (as in Step~2, by \cref{lem:dl:sheaf}(i)--(iii) and \ref{it:prelim:E1}--\ref{it:prelim:E4}), so \cref{lem:tame-trace-bound} applies with $|S\cup A|$ finite punctures and gives $|\sum_{x\in U'(\Fp)}\mathrm{Tr}(\mathrm{Frob}_x\mid\mathcal G')| \le h(s)(|S\cup A|-1)p\le(s+u-1)h(s)p$. For $x\in U'(\Fp)$, $\chi_A(x)\tau_S(x)=-p^{-1}\mathrm{Tr}(\mathrm{Frob}_x\mid\mathcal G')$; $\chi_A$ vanishes on $A$; and the at most $s$ points of $S\setminus A$ contribute at most $p^{-1}\cdot s\cdot sr=s^2r^3$ to $\E_x\chi_A\tau_S$. So $|\E_x\chi_A\tau_S|\le r^2(s+u-1)h(s)+r^3(s+u)s$, which is \eqref{eq:advance:rank-first}. \end{proof} The sizes enter the bounds through the ranks $h(s)$, $h(t)$, the puncture bound $s+t+u$, and the term $r(s+t+u)st$ in \eqref{eq:advance:rank-second}. The root cuts use root sets of sizes $2$ to $11$ and weights with at most ten roots, and they use the rank-sensitive bounds themselves, through the pivot groups of \cref{subsec:advance:ordered-star}. The product rows use root sets of sizes $2$ to $5$, weights with at most four roots, and the uniform constant $512$ below; the constant $6000$ is the corresponding uniform constant for the sizes of the root cuts. \begin{corollary}[Uniform constants]\label{cor:moving-root-uniform} For every odd prime $p$ and $S,T,A\subseteq\Fp$ with $2\le|S|,|T|\le11$ and $|A|\le10$, \[ \Big|\E_x\chi_A\tau_S\tau_T-\frac{\one_{S=T,\ A=\emptyset}}p\Big|\le6000\,p^{-3/2}. \] If $|S|,|T|\le5$ and $|A|\le4$, the constant $6000$ can be replaced by $512$. \end{corollary} \begin{proof} The bracket of \eqref{eq:advance:rank-second} is nondecreasing in $s$, $t$ and $u$. At $(s,t,u)=(11,11,10)$ it is $31\cdot100+1+32\cdot121r=3101+3872r$ (rank $100$, at most $32$ finite punctures); at $(5,5,4)$ it is $13\cdot16+1+14\cdot25r=209+350r$ (rank $16$, at most $14$ finite punctures). Since $p\ge3$, $r\le1/\sqrt3$, and $3101+3872/\sqrt3<6000$, $209+350/\sqrt3<512$. \end{proof} \begin{corollary}[Conditional $L^2$ bound]\label{cor:moving-root-conditional} Let $y_1,\dots,y_d\in\Fp$ be distinct, $\varsigma_1,\dots,\varsigma_d\in\{\pm1\}$, $E\subseteq\Fp$ a set containing $y_1,\dots,y_d$, and $\Phi=\{x\in\Fp\setminus E:\varsigma_j(x-y_j)\in\Qsq\ \text{for}\ j\le d\}$; let $\nu$ be the uniform law on $\Phi$, and suppose $|\Phi|\ge(1-e)p2^{-d}$ with $e<1$, so that $\gamma=p2^{-d}/|\Phi|\le(1-e)^{-1}$. Let $S_1,\dots,S_m$ be distinct subsets of $\Fp$ of sizes in $[2,\bar s]$ and $b_1,\dots,b_m\in\R$. Then \[ \Big\|\sum_lb_l\tau_{S_l}\Big\|_{L^2(\nu)} \le\sqrt\gamma\,r\Big[\sum_lb_l^2+2^dC\,r\Big(\sum_l|b_l|\Big)^2\Big]^{1/2}, \] with $C=6000$ if $\bar s\le11$ and $d\le10$, and $C=512$ if $\bar s\le5$ and $d\le4$. In particular, for at most four pinned labels $y_1,\dots,y_d$ ($d\le4$) and root sets of sizes $2$ to $5$, the factor $2^dC$ may be taken equal to $8192$. \end{corollary} \begin{proof} For $x\in\Phi$ each factor $1+\chi(\varsigma_j(x-y_j))$ equals $2$, and every factor is nonnegative; so the density of $\nu$ relative to uniform probability is at most $\gamma\prod_j\big(1+\chi(\varsigma_j(x-y_j))\big)$, and, the function $F=\sum_lb_l\tau_{S_l}$ being real, $\E_\nu F^2\le\gamma\,\E_x\big[\prod_j(1+\chi(\varsigma_j(x-y_j)))F^2\big]$: dropping the factor $\one[x\notin E]\le1$ from the nonnegative integrand only increases the right side. Expanding the product over the subsets $P\subseteq\{1,\dots,d\}$, with $y(P)=\{y_j:j\in P\}$, \[ \E_x\Big[\prod_j\big(1+\chi(\varsigma_j(x-y_j))\big)F^2\Big] =\sum_P\chi\Big(\prod_{j\in P}\varsigma_j\Big)\sum_{l,l'}b_lb_{l'} \E_x\chi_{y(P)}\tau_{S_l}\tau_{S_{l'}}. \] By \cref{cor:moving-root-uniform} (arbitrary overlaps of $S_l$, $S_{l'}$ and the pins are allowed), the main terms with $P=\emptyset$ and $l=l'$ give $p^{-1}\sum_lb_l^2$, and all error terms, including the diagonal errors, together are at most $2^dC\,r^3(\sum_l|b_l|)^2$ in modulus, since the root sets $S_l$ are distinct. For $d\le4$ and $C=512$, $2^dC\le16\cdot512=8192$. \end{proof} \begin{remark}[One family of moments]\label{rem:trace-moment-family} \Cref{thm:dl:H2} and \eqref{eq:advance:rank-first} are first moments, and \eqref{eq:advance:rank-second} is a second moment, of the same normalized traces: $\Sigma=p^2\E_z\chi_{Z(g)}\tau_f-[m\text{ odd}]\sum_z\chi_{Z(g)}(z)$ when $f$ and $g$ are monic. Their common cohomological step is \cref{lem:tame-trace-bound}. The output statements keep the data needed by their different applications: \cref{thm:dl:H2} keeps the exact number of common roots and the symmetric variant, which the product rows and the completion variance use; \cref{lem:moving-root-moments} keeps the ranks and the puncture counts, which the pivot groups below need. \end{remark} \subsubsection{Grouping stars by a distinguished free label}\label{subsec:advance:ordered-star} The conditional laws to which the moments are applied are those of a half law given all labels but one. \begin{definition}[Pinned half laws]\label{def:pinned-law} Let $U$ be a finite set of $n$ vertices, and for each $i\in U$ let $N^0(i)\subseteq U\setminus\{i\}$, $d_i=|N^0(i)|$ (the degree inside the half; $d^0_i$ in the notation of \cref{sec:spectral}), and signs $\varsigma^0_{ij}\in\{\pm1\}$ ($j\in N^0(i)$). A probability law $\mu$ on the injective maps $x:U\to\Fp$ is a \emph{pinned half law} with count errors $e_i\in[0,1)$ if, for every $i\in U$ and every $x$ in the support of $\mu$, the conditional law of $x_i$ given $x_{-i}=(x_j)_{j\ne i}$ is the uniform law on \[ \Phi_i(x_{-i})=\big\{y\in\Fp\setminus x(U\setminus\{i\}):\ \varsigma^0_{ij}(y-x_j)\in\Qsq\ \text{for all}\ j\in N^0(i)\big\}, \] and $|\Phi_i(x_{-i})|\ge(1-e_i)p2^{-d_i}$. \end{definition} For an oriented graph $G^+$ on $U$, the uniform law $\lambda_p(G^+)$ on $\mathrm{Inj}_p(G^+)$ (\cref{def:graphs:labeling}) is a pinned half law, with $N^0(i)$ the neighbours of $i$, $\varsigma^0_{ij}=+1$ for an edge $(j,i)$ and $-1$ for an edge $(i,j)$: given $x_{-i}$, the admissible values of $x_i$ are exactly $\Phi_i(x_{-i})$. By \cref{lem:extension}, with the at most $n-1$ other labels excluded, one may take $e_i=e_{d_i}(p,n)$ whenever this is below one. \begin{lemma}[Ordered almost orthogonality]\label{lem:ordered-orthogonality} Let $x=(x_1,\dots,x_n)$ be a random vector with values in a finite set, with an arbitrary joint law, and let $F=\sum_{i=1}^nF_i$, where each $F_i$ is a real function of $(x_j)_{j\le i}$. Suppose that for every $i$, almost surely, $\E[F_i^2\mid x_{-i}]\le\alpha_i^2$ and $|\E[F_i\mid x_{-i}]|\le\beta_i$. Then \[ \E F^2\le\sum_i\alpha_i^2+2\sum_i\beta_i\sum_{j0$. Dividing gives (b). (c) Let $j\in T\setminus T'$. Then $w_{T'}$ is a function of $x_{T'}$ and $T'\subseteq U\setminus\{j\}$, so $\E_\mu w_Tw_{T'}=\E_\mu\big[w_{T'}\,\E_\mu[w_T\mid x_{-j}]\big]$, and by (b) and (a) $|\E_\mu w_Tw_{T'}|\le\beta_{T,j}\E_\mu|w_{T'}|\le\beta_{T,j}(qD^{\rm st}_{T'})^{1/2} =\beta_{T,j}(D^{\rm st}_{T'})^{1/2}r$. The case $j\in T'\setminus T$ is symmetric, and one of the two sets is nonempty as $T\ne T'$. For the last assertion expand $\norm{\sum_Tc_Tw_T}^2_\mu=\sum_{T,T'}c_Tc_{T'}\E_\mu w_Tw_{T'}$, and bound the diagonal terms by (a) and the others by (c). \end{proof} For a soft cross kernel the higher-star part of the marginal density of one half relative to $\mu$ is $\sum_{|T|\ge3}c_Tw_T$, where $T$ runs over sets of leaves in that half and $c_T$ is the sum, over the centres in the other half, of the star coefficients of support $T$ (\cref{cor:star-matrix}); for the cut kernel $K_0$ of \cref{sec:spectral} (all soft coefficients equal to $1$ on $E_\times$) $c_T=a_T$ of \eqref{eq:star-function}. The coefficients are arbitrary, so the signs and sizes of the soft entries play no role in the lemma. The certificates of the dense comparisons and of the six-query mixture (\cref{prop:dense-comparison,prop:le-mixture}) evaluate the bound with the count error $\big(\sum_{k\ge3}\binom dk(k-1)\big)r+\big(\binom d2+2^dn\big)q$ in place of $e^-_d(n)$. Since $\sum_{k\ge3}\binom dk(k-1)=a_d+b_d-\binom d2$ (proof of \cref{lem:extension}, and \ref{it:et:compare}), this error exceeds $e^-_d(n)$ by $\big(b_d-\binom d2\big)(r-q)\ge0$ ($b_d=2^{d-1}-1\ge\binom d2$ for $d\ge1$); the certificates use this weaker form: $\beta_{T,j}$ increases with $e^-_d(n)$ through the factor $(1-e^-_d(n))^{-1}$ in \eqref{eq:wt:beta}, so replacing $e^-_d(n)$ by a larger error below $1$ only enlarges the bound. For fixed coefficients, $D^{\rm st}_T$, $\beta_{T,j}/q$ and $\Xi_{TT'}/(qr)$ are nondecreasing functions of $r$: they are built from the polynomials $e_t(p,n)$, $e^-_t(n)$ and $\mathcal B(m,a,u)$ in $r$ with nonnegative coefficients (\ref{it:et:poly}, \eqref{eq:dl:B}) by sums, products, minima and the maps $x\mapsto(1-x)^{-1}$, $x\mapsto(1+x)/(1-x)$ on $[0,1)$. So the bound divided by $q$ is nondecreasing in $r$, and a check at one prime covers every larger prime at which the coefficients are the same (\cref{lem:majorant}). \subsubsection{The complete-star mean}\label{subsec:advance:star-normalizer} The constant $Z_0=\E_{\mu\otimes\mu}K_0$ normalizing the cut kernel $K_0$ of \cref{sec:spectral} needs the mean of the star function, not only its centred part; here the affine constants of \cref{lem:star-trace} must be kept. \begin{lemma}[The complete-star mean]\label{lem:star-mean} Consider spectral data with the star function $h_\star$ and the coefficients $a_T$ of \eqref{eq:star-function}. Let $\mu=\lambda_p(G^+)$ be a pinned half law with count errors $e_i$, fix a total order of $U^+$, let $F_i$, $K_i$, $M_\star$ be the quantities of \cref{subsec:advance:ordered-star} for the coefficients $a_T$ with $|T|\ge3$, and put \[ B_{\rm even}=\sum_{T:\ |T|\ \text{even}\ \ge2}a_T =\sum_{k\in U^+}\Big(\frac12\Big[\prod_{j\in N(k)}\big(1+\chi(\varsigma_{jk})\big) +\prod_{j\in N(k)}\big(1-\chi(\varsigma_{jk})\big)\Big]-1\Big). \] Then $h_\star=\sum_iF_i-B_{\rm even}/p$ on $\mathrm{Inj}_p(G^+)$. Consequently $h_\star-\E_\mu h_\star=P_0\sum_iF_i$, $\norm{h_\star-\E_\mu h_\star}_\mu\le M_\star$, and \[ |\E_\mu h_\star|\le z_\star:=r^2\Big(\sum_iK_i+|B_{\rm even}|\Big). \] \end{lemma} \begin{proof} By \eqref{eq:star-function} and \cref{lem:star-trace}, the supports with $|T|=1$ contribute nothing, those with $|T|=2$ contribute $-a_T/p$, and those with $|T|\ge3$ contribute $a_T\big(\tau_{x(T\setminus\{i(T)\})}(x_{i(T)})-\one_{|T|\ \rm even}/p\big)$. Summing, $h_\star=\sum_iF_i-p^{-1}\big(\sum_{|T|=2}a_T +\sum_{|T|\ge4\ \rm even}a_T\big)=\sum_iF_i-B_{\rm even}/p$. For the second expression of $B_{\rm even}$: for a centre $k$ with signs $c_j=\chi(\varsigma_{jk})$, $\sum_{T\subseteq N(k),\ |T|\ \rm even}\prod_{j\in T}c_j =\frac12\big[\prod_j(1+c_j)+\prod_j(1-c_j)\big]$, and the empty support, which contributes $1$, is subtracted. (For $|N(k)|\ge1$ a centre whose signs $c_j$ are all equal contributes $2^{|N(k)|-1}-1$, and every other centre contributes $-1$.) Then $\E_\mu h_\star=\sum_i\E_\mu F_i-B_{\rm even}/p$ and $h_\star-\E_\mu h_\star=P_0\sum_iF_i$, and \cref{prop:advance:ordered-star} gives both bounds, as $1/p=r^2$. \end{proof} \begin{remark}[How the mean enters, and what is not done]\label{rem:star-mean-scope} The row stars have the same mean as the column stars, and together the stars contribute $2\E_\mu h_\star$ to the normalizer of the cut kernel (\cref{lem:spec:stars}(c)). This is how $z_\star$ and $Z_\star\ge2|\E_\mu h_\star|$ enter hypothesis \ref{it:record:star-H3} of \cref{thm:record:direct-star}, and how the same bound enters the normalizer error of route~A (\cref{thm:spectral-criterion}). The number $z_\star$ depends on the class of $p$ through the signs $\chi(\varsigma_{jk})$: the root caps proved by Route~B, applied at $p\equiv3\pmod4$, use its value for that class (\cref{lem:record:direct-star-inputs}(ii)), and the completed-root caps use the larger of its two values (\cref{lem:upper-completed-root}). Two cautions apply. The affine constants are kept: the two-leaf stars and the constants $-\one_{|T|\ \rm even}/p$ make up $B_{\rm even}/p$, which does not vanish in the mean. And the estimate bounds $\E_\mu h_\star$ itself; the bound for the centred part $P_0h_\star=h_\star-\E_\mu h_\star$ is not used in its place. For one half law the mean is known exactly. On the half reference of the middle root cut L20, the graph law on the six vertices $(a_0,a_1,b_0,b_1,c_0,c_1)$ whose only edges are the four arrows $a_i\to c_j$ ($i,j\in\{0,1\}$) from the pair $(a_0,a_1)$ to the pair $(c_0,c_1)$, the remaining two vertices $(b_0,b_1)$ being isolated, the two-leaf star means cancel, the three-leaf ones add up to zero at each centre, and the four-leaf ones are given exactly in terms of the graph moment $M_{G_5}$ of the variance credits (\cref{lem:l20-star-mean}, proved in \cref{sec:variance} next to that moment). The normalizer of that cut uses this exact value instead of the general bound (\cref{subsec:middle-l20}). \end{remark} \subsection{Where these estimates enter}\label{subsec:second-order-uses} \Cref{tab:second-order-uses} lists every use in the final construction. The sheaves of \cref{lem:dl:sheaf} stand behind all rows except those of \cref{thm:dl:K,cor:dl:normalized,cor:raw-pair-maps}, which rest on the representation theory of $\mathrm{PGL}_2(\Fp)$, and the last row, an external evaluation through a modular form (\cref{subsec:external:modular}). \begin{table}[ht] \small \caption{Where the second-order estimates enter.}\label{tab:second-order-uses} \begin{tabular}{@{}>{\raggedright\arraybackslash}p{3.1cm}% >{\raggedright\arraybackslash}p{5.6cm}>{\raggedright\arraybackslash}p{5.4cm}@{}} \toprule estimate & enters as & in\\ \midrule \cref{thm:dl:K}, \cref{cor:dl:normalized}(a) & the norm $2r^2$ of a two-vertex strongly connected block of a witness kernel (\cref{lem:matching:kernel}), hence the complete-rectangle coefficient of the compressed partitions (\cref{lem:advance:compressed-partition}) & the nonstar bounds of every spectral cap: the twelve-label grid, the caps of the root cut L20 (\cref{subsec:middle-l20,sec:positive-roots}), the ten nonroot upper cuts, $N_{\rm ns}$ of the direct-star root (\cref{lem:record:direct-star-inputs}(iii)), the pinned rows of \cref{subsec:push:pinnedremainder}\\ \cref{cor:dl:normalized} & the injective $K_{2,2}$ core $2r^2$ of a matched neighbourhood in the completion variance (\cref{lem:push:localvariance}, through \cref{lem:matching:kernel}(b)) & the coupling block (\cref{cor:spec2:coupling}) of the completed-root caps (\cref{lem:upper-completed-root}) from $2^{52}$\\ \cref{cor:raw-pair-maps} & the remainder $\norm R^2\le c_0q^2$ of the raw pair maps (b), and the norms $r$ and $\sqrt{q(1-q)}$ of the maps of (a) & the square identity, the linear trace and the layer squares of the positive roots (\cref{lem:root-square,lem:root-linear,prop:root-layer})\\ \cref{thm:dl:H2} & the pair term of the completion variance, through the coefficient triples of $\mathcal B(a,b,0)$ (\cref{rem:dl:H2-sharp}(ii)) & the coupling block of the completed-root caps (\cref{lem:upper-completed-root}) from $2^{52}$\\ \cref{thm:dl:H2} & the complete conditional means (PR1) of the product rows, with $p\,\mathcal B(4,4,0)<40p$ (\cref{rem:dl:H2-sharp}(iii), \cref{subsec:advance:product-rows}) & the row inputs of the upper bands\\ \cref{lem:wt:stars} (through \cref{thm:dl:H2}) & the $L^2$ norm of the weighted higher-star marginals of a soft cross kernel & the dense comparisons and the six-query mixture of the upper range (\cref{prop:dense-comparison,prop:le-mixture})\\ \cref{cor:moving-root-uniform,cor:moving-root-conditional} & the weighted moments (PR7) and the conditional $L^2$ bounds (PR8) of the product rows & the row inputs of the upper bands\\ \cref{prop:advance:ordered-star,lem:star-mean} & $M_\star$, $z_\star$ and $Z_\star$ (\cref{lem:record:direct-star-inputs}(i),(ii)) & the direct-star root on the upper bands from $P_3$ to $2^{52}$ (\cref{thm:record:direct-star}) and the completed-root caps from $2^{52}$ (\cref{lem:upper-completed-root})\\ \cref{thm:ahlgren-ono} (\cref{app:external}) & the bounds $-(1-q)(2qr+q^2)\le M_{G_5}\le(1-q)(2qr-q^2)$ of the graph moment \eqref{eq:record:modular-moment}, in the second moment of a neighbourhood count (\cref{lem:record:weighted-moment}) and in the quartic star mean (\cref{lem:l20-star-mean}) & the root-half variances $\chi_p$ (the $\chi^2$-divergences of \cref{sec:variance}, not the character $\chi_p$ above) of the middle roots (\cref{lem:record:root-marginal}) in the restorations and the completion of the root cut L20 (\cref{subsec:middle-l20}); the star mean of that cut; the linear prices and the normalization of the positive roots (\cref{lem:root-linear,lem:root-normalization})\\ \bottomrule \end{tabular} \end{table} \paragraph{Consequences and what to read next.} This section used the following inputs; its outputs are the three second-order estimates of the opening, whose uses are listed in \cref{tab:second-order-uses}. From Part~II: Weil's bound (\cref{thm:weil}), Jacobi sums (\cref{thm:jacobi}), the two-root identity \eqref{eq:two-root}, the Paley operator (\cref{lem:square-shift}(c)), and, in \cref{rem:pivot-order} and in the discussion after \cref{lem:wt:stars} only (not in any proof), the admissible majorants of \cref{lem:majorant}. From Part~IV: strict-square labellings and the extension count (\cref{def:graphs:labeling,lem:extension}), to see that half laws are pinned and, with the one-vertex conditional laws and tuple densities of graph laws (\cref{lem:graphs:vertex}\ref{it:vertex:dens},\ref{it:vertex:tuple}), the sequential counts (\cref{lem:graphs:sequential}), the graded lower count \cref{lem:extension}\ref{it:ext:lower} and the properties \ref{it:et:compare}, \ref{it:et:poly} of the count errors, in \cref{lem:wt:stars}; spectral data (\cref{def:spec:data}) for the cross signs of the star function; and, in remarks and discussion only (not in any proof), \cref{lem:spec:stars,cor:star-matrix,lem:swapped-rectangle}. From \cref{app:external}: the character table of $\mathrm{GL}_2(\Fp)$ with its class sizes (\cref{thm:prelim:gl2}); the $\ell$-adic facts \ref{it:prelim:E1}--\ref{it:prelim:E4}; the trace formula, the cohomology of open curves, Deligne's theorem and the Euler characteristic formula (\cref{thm:prelim:lefschetz,thm:prelim:curves,thm:prelim:weights,thm:prelim:gos}); and the Katz--Sarnak family with its self-duality and its local monodromy at the finite roots (\cref{thm:prelim:ks}). \space % End sections/15_second_order % Begin sections/16_extraction \section{The non-star part of the character expansion and coincident labels}\label{sec:extraction} \paragraph{What this section proves and how to read it.} Expanding a cut kernel in characters gives terms indexed by sets of cross pairs. Terms whose pairs share an endpoint (\emph{stars}) are handled in \cref{sec:spectral}; this section bounds the remaining terms and the terms where labels coincide, showing both are second order with explicit constants. No new cancellation is proved here: the work is bookkeeping to keep constants small when many subsets are summed. \emph{Extraction} means the following choice, made for each group of subsets (a \emph{class} $\mathcal C(P,A)$: pairs in $P$ present, pairs in $A$ absent, others free): choose two disjoint present pairs (\emph{witnesses}, certifying second order), choose sets of vertices meeting every other undecided pair (a \emph{vertex cover}, whose labels are conditioned on), and choose labelling orders. An \emph{extraction datum} records these choices (called a ``record of a class'' in the text below, not to be confused with records of Part~III). Inputs: \cref{sec:cuts,sec:dl}. Output: the per-class bound (\cref{subsec:extraction:extraction}) used by the spectral criteria. A first reading should follow the class definition and the statement of the per-class bound; the counting details are reference material. Writing each cross constraint at $e=(j,k)$ as $\tfrac12(1+\chi(\varsigma_{jk}(x'_k-x_j)))$ gives the expansion; the non-star part $T_{\rm ns}$ is second order because a non-star contains two disjoint pairs, and the coincidence part $T_{\rm coll}$ corrects for half labellings sharing a label. The difficulty is the constant at the first prime of a range, where $2^{m_\times}$ subsets are summed; it is kept small by stopping at the first two disjoint pairs, conditioning only on a vertex cover, counting constraints met by each vertex, and labelling the coincident vertices (those forced to carry equal labels) first in the coincidence count. \subsection{The character expansion and the compressed partition}\label{subsec:extraction:partition} \paragraph{Setting.} Throughout this section, except in \cref{subsec:push:pinnedremainder}, $(G,\vartheta,U^+,\mathfrak o)$ are spectral data (\cref{def:spec:data}) with the notation fixed there: $n=|U^+|$, the half graph $G^+$, adjacency $j\sim k$ in $G^+$, the degrees $d^0_k$ and $\Delta^+=\max_kd^0_k$, the cross signs $\varsigma_{jk}$, the neighbourhoods $N(k)=\{j:\varsigma_{jk}\ne0\}$ with $r_k=|N(k)|$, $d_k=d^0_k+r_k$, $\Delta=\max_kd_k$, the cross pairs $E_\times$ and $m_\times=|E_\times|$. We write $\operatorname{Adj}(i)=\{j\in U^+:j\sim i\}$, so that $|\operatorname{Adj}(i)|=d^0_i$, and $e(L)$, $e(L,L')$ for the numbers of edges of $G^+$ inside $L$ and between disjoint sets $L,L'$. The prime $p$ is odd, $r=p^{-1/2}$, $e_t(p,n')=2^t(h_tr+n'r^2)$ is the count error of \eqref{eq:graphs:et}, $\mathcal I^+=\operatorname{Inj}_p(G^+)$ and $\mu=\lambda_p(G^+)$ is the half law. For $Y\subseteq U^+$ put \[ R_Y=\prod_{i\in Y}\frac{1+e_{d^0_i}(p,n)}{1-e_{d^0_i}(p,n)},\qquad R_{\rm full}=R_{U^+},\qquad \hat e=e_{\Delta^+}(p,n), \] the completion ratios of \cref{lem:graphs:vertex} for the graph $G^+$. Under (S1) at $p$, $e_t(p,n')<1$ for $t\le\Delta$ and $n'\le2n$; in particular $\hat e<1$, and every factor of every $R_Y$ is defined and at least one. The two labellings of a pair $(x,x')\in\mathcal I^+\times\mathcal I^+$ live on two copies $X$ and $Z$ of $U^+$; in a cross pair $(j,k)$ the $x$-endpoint $j$ is a vertex of $X$ and the $x'$-endpoint $k$ a vertex of $Z$. Graph quantities ($\operatorname{Adj}$, $d^0$, $N$, $r$) of a vertex of $X$ or $Z$ are those of the corresponding vertex of $U^+$. The characters $\chi_e(x,x')=\chi(\varsigma_{jk}(x'_k-x_j))$ of the cross pairs $e=(j,k)$, their products $\chi_S$, the operators $T_S$ on $L^2(\mu)$ with kernel $\chi_S$ relative to $\mu\otimes\mu$, the stars and nonstars, $T_{\rm ns}=\sum_{S\ \rm nonstar}T_S$, and the collision operator $T_{\rm coll}$, whose kernel $K_{\rm coll}$ is $\prod_{e\in E_\times}(1+\chi_e)$ on the pairs $(x,x')$ that share a label and $0$ elsewhere, are those of \cref{subsec:spec:perp}. By \cref{lem:spec:expansion}, $2^{m_\times}$ times the cut kernel is $\one\otimes\one+\sum_{S\ \rm star}T_S+T_{\rm ns}-T_{\rm coll}$ \eqref{eq:record:root-kernel}, and $K_{\rm coll}$ is nonnegative and symmetric; the constants and the stars are treated in \cref{sec:spectral}. By \cref{lem:spec:elementary}, $(j,k)\in E_\times$ iff $(k,j)\in E_\times$; so $j\in N(k)$ iff $k\in N(j)$, and $r_j$ is also the number of cross pairs with $x$-endpoint $j$. \paragraph{Graded errors.} Every statement of this section outside \cref{subsec:push:pinnedremainder}, whose rows carry their own error $e^{\rm pin}_d$, holds with the same proof when the coarse error $e_t(p,n')$ is replaced throughout (in $R_Y$, $R_{\rm full}$, $\hat e$, the vertex and leaf factors, $L_{\rm int}$, $\Upsilon$ and $\Upsilon_k$) by the graded error $e^-_t(n')$ of \eqref{eq:graphs:graded}. Indeed the proofs use three properties of $e_t(p,n')$: it bounds the relative error of a count of \cref{lem:extension} from above whatever the excluded set, and from below when at most $n'$ labels are excluded (\cref{lem:extension}\ref{it:ext:upper},\ref{it:ext:coarse}); it is nondecreasing in $t$ and $n'$ and a polynomial in $r$ with nonnegative coefficients (\ref{it:et:poly}); and the densities and completion ratios of \cref{lem:graphs:vertex} are formed with it. The graded error has the first two properties by \cref{lem:extension}\ref{it:ext:upper},\ref{it:ext:lower} with \ref{it:et:compare} and \ref{it:et:poly}. For the third, \cref{lem:graphs:vertex}\ref{it:vertex:dens}--\ref{it:vertex:tuple} hold with $e^-_t(n)$ in place of $e_t(p,n)$, under $e^-_\Delta(n)<1$: in their proofs \cref{lem:extension}\ref{it:ext:coarse} enters only through lower counts, for which \ref{it:ext:lower} with $z=n$ serves, and \cref{lem:graphs:sequential}\ref{it:seq:count},\ref{it:seq:coarse} for the coarse pair may be replaced by \ref{it:seq:count} for the graded pair, whose ratio $\prod_i(1+e^+_{t_i})/(1-e^-_{t_i}(n))$ is at most $\prod_i(1+e^-_{d_i}(n))/(1-e^-_{d_i}(n))$ by \ref{it:et:compare} and \ref{it:et:poly}, since $t_i\le d_i$. Where a proof uses the explicit form of $e_t(p,n')$ (\cref{cor:extraction-compressed}), it applies through $e^-_t(n')\le e_t(p,n')$ (\ref{it:et:compare}); in particular, under (S1), $e^-_t(n')<1$ for $t\le\Delta$ and $n'\le2n$. The \emph{error pair of the setting} is the coarse pair or the graded pair of \cref{def:graphs:error-pair}; one choice is made for all the errors of a bound, and the nonstar coefficients of the root cuts of the upper range below $2^{52}$ use the graded one. \paragraph{Classes.} For disjoint $P,A\subseteq E_\times$ the \emph{class} $\mathcal C(P,A)=\{S:P\subseteq S\subseteq E_\times\setminus A\}$ consists of the sets in which the pairs of $P$ are \emph{present}, those of $A$ \emph{absent}, and those of $F=E_\times\setminus(P\cup A)$ \emph{free}. A pair is \emph{decided} if it is present or absent; pairs of $X\times Z$ outside $E_\times$ count as absent. The \emph{mass} of a class is $2^{|F|}$, and $T_{\mathcal C}=\sum_{S\in\mathcal C}T_S$. An \emph{exact partition} of a family of subsets of $E_\times$ is a set of pairwise disjoint classes whose union is the family. If $\mathcal C$ is the disjoint union of $\mathcal C_1$ and $\mathcal C_2$, then $T_{\mathcal C}=T_{\mathcal C_1}+T_{\mathcal C_2}$. Hence bounds for the classes of an exact partition add up to a bound for the whole family, and for a class split in two the smaller of a bound for the class and the sum of bounds for its two parts is again a bound for the class. \begin{definition}[Witnesses and covers]\label{def:extraction:witness} Let $\mathcal C=\mathcal C(P,A)$ be a class with free pairs $F$, and $k\ge1$. \begin{enumerate}[label=\textup{(\alph*)}] \item A \emph{witness of size $k$} consists of pairs $(j_1,k_1),\dots,(j_k,k_k)\in P$ with distinct $j_i$ and distinct $k_i$ such that, with $V=\{j_1,\dots,j_k\}\subseteq X$ and $W=\{k_1,\dots,k_k\}\subseteq Z$, every pair of the \emph{rectangle} $E_{VW}=(V\times W)\cap E_\times$ is decided; call this \textup{(W$_k$)}. \item The \emph{witness digraph} $D_{\mathcal C}$ has the vertex set $\{1,\dots,k\}$ and an arc $i\to l$ ($i\ne l$) whenever $(j_i,k_l)\in P$. If all its strongly connected components have at most two vertices, $\beta(\mathcal C)$ denotes the number of components with two vertices. \item A \emph{cover} is a pair $C_x\subseteq X\setminus V$, $C_z\subseteq Z\setminus W$ such that every pair of $P\cup F$ outside $V\times W$ has its $x$-endpoint in $C_x$ or its $x'$-endpoint in $C_z$; call this \textup{(VC$_k$)}. The \emph{integrated} vertices are $U_x=X\setminus(V\cup C_x)$ and $U_z=Z\setminus(W\cup C_z)$. The pair $(X\setminus V,Z\setminus W)$ is always a cover. \end{enumerate} \end{definition} The partition lemma concerns only the combinatorics of the cross pairs, and we state it for an arbitrary finite set $E_\times\subseteq X\times Z$ of pairs, symmetric or not (the pinned rows of \cref{subsec:push:pinnedremainder} need a set that is not symmetric). For such a set let $r^X_j$ and $r^Z_k$ be the numbers of its pairs with $x$-endpoint $j$ and with $x'$-endpoint $k$; for spectral data both are the cross degrees $r_j$, $r_k$. Two pairs are \emph{disjoint} if their $x$-endpoints differ and their $x'$-endpoints differ. \begin{lemma}[The compressed partition]\label{lem:advance:compressed-partition} Let $E_\times\subseteq X\times Z$ be finite, $m_\times=|E_\times|$, with a total order $\prec$. \begin{enumerate}[label=\textup{(\alph*)}] \item A subset of $E_\times$ contains no two disjoint pairs if and only if it is empty or a star. The empty set and the stars are \[ 1+m_\times+\sum_j\bigl(2^{r^X_j}-1-r^X_j\bigr)+\sum_k\bigl(2^{r^Z_k}-1-r^Z_k\bigr) \] subsets; so the masses of the classes of an exact partition of the nonstar subsets add up to $2^{m_\times}$ minus this number. \item For a nonstar $S$ let $e=(a,b)$ be its first pair. Exactly one of the following holds, and it defines a class $\mathcal C(S)=\mathcal C(P,A)$. \begin{enumerate}[label=\textup{(\Alph*)}] \item Some pair of $S$ is disjoint from $e$. Let $f=(a',b')$ be the first one, let $\mathrm{Con}=\{(a,b'),(a',b)\}\cap E_\times$ be the \emph{connectors}, and \[ P=\{e,f\}\cup(S\cap\mathrm{Con}),\qquad A=\{g:g\prec e\}\cup\{g\prec f:g\text{ disjoint from }e\}\cup(\mathrm{Con}\setminus S). \] \item No pair of $S$ is disjoint from $e$. Then $S$ contains, besides $e$, a pair with $x$-endpoint $a$ and a pair with $x'$-endpoint $b$ (the \emph{arms} of $e$). Let $g_1=(a,b'')$ and $g_2=(a'',b)$ be the first arms of the two kinds, let $A_1$ ($A_2$) be the set of pairs $g\ne e$ with $x$-endpoint $a$ ($x'$-endpoint $b$) and $g\prec g_1$ ($g\prec g_2$), and \[ P=\{e,g_1,g_2\},\qquad A=\{g:g\prec e\}\cup A_1\cup A_2\cup\{g:g\text{ disjoint from }e\}. \] \end{enumerate} Every element of $\mathcal C(S)$ is a nonstar whose class is $\mathcal C(S)$. So the distinct classes $\mathcal C(S)$ form an exact partition of the nonstar subsets, the \emph{compressed partition}. In case \textup{(A)} the pairs $e,f$, and in case \textup{(B)} the arms $g_1,g_2$, form a witness of size two of $\mathcal C(S)$. Its witness digraph is a two-cycle if, in case \textup{(A)}, both connectors are present, and it is acyclic otherwise. \item Let $\mathcal C(P,A)$ be a class and $g$ a free pair. The \emph{children} $\mathcal C(P\cup\{g\},A)$ and $\mathcal C(P,A\cup\{g\})$ partition it; so replacing a class of an exact partition by its children, any number of times, gives an exact partition. A witness of $\mathcal C(P,A)$ is a witness of each child, with the same witness digraph, and a cover of $\mathcal C(P,A)$ is a cover of each child. If $k$ pairs of $P$ have distinct $x$-endpoints and distinct $x'$-endpoints, they form a witness of size $k$ of every class obtained from $\mathcal C(P,A)$ by deciding, one at a time, the undecided pairs of their rectangle. \end{enumerate} \end{lemma} \begin{proof} (a) Let $S$ be nonempty without two disjoint pairs, and fix $e=(a,b)\in S$. Every other pair of $S$ shares $a$ or $b$ with $e$. If $S$ contained a pair $(a,b_1)$ with $b_1\ne b$ and a pair $(a_1,b)$ with $a_1\ne a$, these two would be disjoint. So all pairs of $S$ have the $x$-endpoint $a$, or all have the $x'$-endpoint $b$. Conversely any two pairs of a star share an endpoint. A set of at least two pairs is not both a row star and a column star, since two pairs with the same two endpoints coincide, while a single pair is both. Counting the empty set, the $m_\times$ single pairs, the row stars of at least two pairs inside each row and the column stars of at least two pairs inside each column gives the number. (b) By (a) a nonstar $S$ contains two disjoint pairs, and so it has a first pair $e$ and falls in exactly one of the two cases. In case (B) every pair of $S$ shares an endpoint with $e$, and $S$ is neither contained in the row of $e$ nor in its column, which gives the arms; $g_1$ and $g_2$ are disjoint, and both follow $e$. In both cases $P\cap A=\emptyset$, $P\subseteq S$, and no pair of $A$ lies in $S$: the pairs before $e$ by the choice of $e$, the pairs disjoint from $e$ before $f$ by the choice of $f$, the arms before $g_1$, $g_2$ by the choice of the arms, and in case (B) the pairs disjoint from $e$ by assumption. So $S\in\mathcal C(S)$. Let $S'\in\mathcal C(S)$. In case (A), $e\in S'$ and no pair before $e$ lies in $S'$, so $e$ is the first pair of $S'$; $f\in S'$ is disjoint from $e$ and no pair disjoint from $e$ precedes it in $S'$; and $S'\cap\mathrm{Con}=S\cap\mathrm{Con}$. Hence $S'$ is a nonstar in case (A) with the same $e$, $f$ and connectors, and $\mathcal C(S')=\mathcal C(S)$. In case (B), $e$ is again the first pair of $S'$, no pair of $S'$ is disjoint from $e$, and $g_1$, $g_2$ are the first arms of $S'$; $S'$ is a nonstar because it contains the disjoint pairs $g_1,g_2$, and $\mathcal C(S')=\mathcal C(S)$. So two classes $\mathcal C(S_1)$, $\mathcal C(S_2)$ with a common element coincide, and the classes cover the nonstar subsets exactly once. In case (A) take $(j_1,k_1)=e$ and $(j_2,k_2)=f$, so $V=\{a,a'\}$ and $W=\{b,b'\}$. The rectangle consists of $e$, $f$ and the connectors, all decided; $D_{\mathcal C}$ has the arc $1\to2$ iff $(a,b')\in P$ and the arc $2\to1$ iff $(a',b)\in P$. In case (B) take $(j_1,k_1)=g_1=(a,b'')$ and $(j_2,k_2)=g_2=(a'',b)$, so $V=\{a,a''\}$ and $W=\{b'',b\}$. The rectangle consists of $g_1$, $g_2$, the present pair $e=(a,b)$, which gives the arc $1\to2$, and the pair $(a'',b'')$, which is disjoint from $e$ and therefore absent; there is no arc $2\to1$. (c) The children are the elements of $\mathcal C(P,A)$ that contain $g$ and those that do not. A child has more present and more absent pairs; the witness pairs stay present, the rectangle stays decided, and $P\cap(V\times W)$ does not change, because $g$ was free and so lies outside the rectangle. The non-absent pairs of a child are non-absent in the parent, so (VC$_k$) passes to the child. Deciding the undecided pairs of a rectangle produces classes in which the rectangle is decided, which is (W$_k$). \end{proof} \begin{remark}[Comments on the partition]\label{rem:extraction-partition} (1) The arm case cannot be omitted: a three-edge path whose middle pair comes first contains no pair disjoint from that pair. In the arm case the first pair $e$ is a present connector of the witness, not a witness pair. (2) A set $J\times K$ with $|J|,|K|\ge2$ contains two disjoint pairs, so complete bipartite subsets lie in classes and need no separate estimate. (3) Refinement does not worsen the available bound: by (c) the witness and cover of a class remain valid at all its descendants, so the size-two bound is available for every class obtained by repeated refinement, and such a class may keep the smaller of its own bound and the sum of the bounds of its children. Larger witnesses are found along augmenting paths: if the present pairs contain a matching of size $k+1$, the symmetric difference with a matching $M$ of size $k$ contains an augmenting path for $M$ (Berge's lemma), of length one, three or five when $k=2$. The search for witnesses is heuristic and lies outside the proof; a proposed witness is used only after \textup{(W$_k$)} and the digraph condition have been verified. (4) Summed over a refinement of the compressed partition, the bounds for the classes at which refinement stops (the leaves) give the nonstar coefficients $C_k(Q)$ of \cref{cor:extraction-leaf}(b). Every choice (the order, the pair to decide, the witness, when to stop, the cover and the orders) affects only constants. The certificates make the choices once, in floating point at one prime, and fix them for all primes; their builders also check that the masses of the classes and the number in (a) add up to $2^{m_\times}$, and that a refined union of classes carries the mass it replaces. These checks accompany the proof; they do not replace it. (In the data files, whose names are reproduced in \cref{app:certificates}, the classes of case~(B) are called type~A and those of case~(A) type~B --- the reverse of the letters in this text; the cases here are always referred to as (A) and (B).) \end{remark} \subsection{Bounding a class by two designated pairs}\label{subsec:extraction:kernel} Fix a class $\mathcal C(P,A)$ and its designated witness pairs (\cref{def:extraction:witness}). After conditioning on all other labels, the kernel that remains on the witness labels is a product of characters $\chi(\pm(y_l-x_i))$ over a set $\mathcal K$ of pairs. The lemma bounds such a kernel: its compressed norm is at most $2^\beta r^k$ ($k$ the number of witness labels, so second order as soon as $k\ge2$), provided the directed graph of the pairs has no strongly connected component larger than a $2\times2$ rectangle, with $\beta$ the number of two-vertex components. These components use the four-cycle bound of \cref{sec:dl}; larger components require a separate estimate. \begin{lemma}[Witness kernels]\label{lem:matching:kernel} Let $k\ge1$, let $\mathcal K\subseteq\{1,\dots,k\}^2$ contain the diagonal pairs $(i,i)$, let $\varsigma_{il}\in\{\pm1\}$ for $(i,l)\in\mathcal K$, and let $T_{\mathcal K}$ be the operator on $L^2(\Fp^k)$, with uniform probability, given by \[ (T_{\mathcal K}f)(x)=\E_{y\in\Fp^k}\Bigl[\prod_{(i,l)\in\mathcal K} \chi\bigl(\varsigma_{il}(y_l-x_i)\bigr)\,f(y)\Bigr]. \] Let $D_{\mathcal K}$ be the digraph on $\{1,\dots,k\}$ with an arc $i\to l$ for every $(i,l)\in\mathcal K$ with $i\ne l$. \begin{enumerate}[label=\textup{(\alph*)}] \item If $D_{\mathcal K}$ is acyclic, then $\norm{T_{\mathcal K}}\le r^k$. \item Suppose that every strongly connected component of $D_{\mathcal K}$ has at most two vertices and that $\beta$ of them have two. Let $P_{\rm in}$ and $P_{\rm out}$ be the multiplications by the indicators of sets of tuples $y$, respectively $x$, with $y_i\ne y_l$, respectively $x_i\ne x_l$, for every two-vertex component $\{i,l\}$ (for instance the injective tuples). Then $\norm{P_{\rm out}T_{\mathcal K}P_{\rm in}}\le2^\beta r^k$. \item $D_{\mathcal K}$ is acyclic if and only if the identity is the only permutation $\pi$ of $\{1,\dots,k\}$ with $(i,\pi(i))\in\mathcal K$ for all $i$, that is, if and only if the diagonal is the only perfect matching contained in $\mathcal K$. \item \emph{Inserted multipliers.} Let $k=2$ and $\mathcal K=\{(1,1),(2,2)\}$, and let $F_{\rm out}(x_1,x_2)$, $F_{\rm mid}(x_1,y_2)$ and $F_{\rm in}(y_1,y_2)$ be bounded functions. The operator on $L^2(\Fp^2)$ with kernel \[ \chi\bigl(\varsigma_{11}(y_1-x_1)\bigr)\,\chi\bigl(\varsigma_{22}(y_2-x_2)\bigr)\, F_{\rm out}(x_1,x_2)\,F_{\rm mid}(x_1,y_2)\,F_{\rm in}(y_1,y_2) \] has norm at most $r^2\norm{F_{\rm out}}_\infty\norm{F_{\rm mid}}_\infty \norm{F_{\rm in}}_\infty$, and so has the operator with $F_{\rm mid}(y_1,x_2)$ in place of $F_{\rm mid}(x_1,y_2)$. \end{enumerate} \end{lemma} \begin{proof} Let $C_1,\dots,C_{n_c}$ be the strongly connected components of $D_{\mathcal K}$, ordered so that every arc between two components goes from an earlier to a later one. Consider functions of mixed coordinates: $x_i$ for $i$ in the components already treated and $y_i$ for the others, with uniform probability. Step $s$ replaces the coordinates $y_{C_s}$ by $x_{C_s}$: \[ g\longmapsto M_s\cdot B_sg,\qquad B_sg=\E_{y_{C_s}}\Bigl[\prod_{(i,l)\in\mathcal K\cap C_s^2} \chi\bigl(\varsigma_{il}(y_l-x_i)\bigr)\,g\Bigr],\qquad M_s=\prod_{(i,l)\in\mathcal K_s}\chi\bigl(\varsigma_{il}(y_l-x_i)\bigr), \] where $\mathcal K_s$ is the set of $(i,l)\in\mathcal K$ with $i\in C_s$ and $l$ in a later component. When step $s$ is performed the coordinates $x_{C_s}$ have just been created and every $y_l$ with $l$ in a later component is still present, so $M_s$ is a function of the current coordinates. Every pair of $\mathcal K$ is used exactly once: a pair inside a component in its block $B_s$, and a pair between two components in $M_s$ for the component $C_s$ of its first index, since its second index lies in a later component. Hence $T_{\mathcal K}=M_{n_c}B_{n_c}\cdots M_1B_1$. Each $M_s$ is a multiplication by a function of modulus at most one, and $B_s$ is the operator of the block $C_s$ tensored with the identity in the other coordinates, which has the same norm. (a) If $D_{\mathcal K}$ is acyclic, every component is a single vertex $i$, and $B_s$ is $h\mapsto\E_y\chi(\varsigma_{ii}(y-x))h(y)=\chi(\varsigma_{ii})Ch$ in the coordinate $i$, with the Gauss operator $C$ of \cref{lem:spec:gauss}, of norm $r$. So $\norm{T_{\mathcal K}}\le r^k$. (b) For a two-vertex component $C_s=\{i,l\}$, strong connectivity gives both arcs, so the kernel of $B_s$ is the complete rectangle $\prod_{a,b\in\{i,l\}}\chi(\varsigma_{ab}(y_b-x_a))$. Let $Q_{\rm in}$ and $Q_{\rm out}$ be the multiplications by $\one[y_i\ne y_l]$ and by $\one[x_i\ne x_l]$. The steps before $s$ act on other coordinates or multiply pointwise, so they commute with $Q_{\rm in}$, and $Q_{\rm in}P_{\rm in}=P_{\rm in}$. The steps after $s$, and $M_s$, act on other coordinates or multiply pointwise, so they commute with $Q_{\rm out}$, and $P_{\rm out}Q_{\rm out}=P_{\rm out}$. Hence $Q_{\rm in}$ may be inserted immediately before $B_s$ and $Q_{\rm out}$ immediately after it without changing $P_{\rm out}T_{\mathcal K}P_{\rm in}$, for every two-vertex component. By \cref{cor:dl:normalized}(a) with $a=b=2$, $\norm{Q_{\rm out}B_sQ_{\rm in}}\le2/p=2r^2$, and the singleton blocks have norm $r$ as in (a). Multiplying, $\norm{P_{\rm out}T_{\mathcal K}P_{\rm in}}\le r^{k-2\beta}(2r^2)^\beta=2^\beta r^k$. (c) If $i_1\to i_2\to\dots\to i_\ell\to i_1$ is a directed cycle with distinct vertices, the permutation with $\pi(i_s)=i_{s+1}$ (indices modulo $\ell$) and $\pi(i)=i$ otherwise is a second perfect matching. Conversely, if $\pi\ne\mathrm{id}$ is a perfect matching in $\mathcal K$, every $i$ with $\pi(i)\ne i$ gives an arc $i\to\pi(i)$, and following a cycle of $\pi$ gives a directed cycle. (d) Let $M_F$ be the multiplication by $F$, and let $C_\varsigma\otimes I$ and $I\otimes C_\varsigma$ be the Gauss operator $(C_\varsigma h)(a)=\E_b\chi(\varsigma(b-a))h(b)$ of \cref{lem:spec:gauss} acting in the first and in the second coordinate. Applied to $f(y_1,y_2)$, the operator multiplies by $F_{\rm in}$, replaces $y_1$ by $x_1$ through the kernel $\chi(\varsigma_{11}(y_1-x_1))$, multiplies by $F_{\rm mid}(x_1,y_2)$, replaces $y_2$ by $x_2$ through $\chi(\varsigma_{22}(y_2-x_2))$, and multiplies by $F_{\rm out}$: it is $M_{F_{\rm out}}(I\otimes C_{\varsigma_{22}})M_{F_{\rm mid}}(C_{\varsigma_{11}}\otimes I)M_{F_{\rm in}}$. With $F_{\rm mid}(y_1,x_2)$ the two transforms are applied in the other order. Each Gauss operator has norm $r$, and each multiplication has norm at most the supremum of its function. \end{proof} \begin{remark}[The witness kernels that occur]\label{rem:extraction-kernels} For a witness of size two the rectangle is a matching, a three-edge path (one connector present) or a complete rectangle (both present). The first two are acyclic, so their kernels have norm at most $r^2=1/p$ for independent uniform labels, with no injectivity condition (the \emph{incomplete-rectangle bound}). The complete rectangle has norm at most $2r^2$ on distinct pairs; numerical evidence for the sharpness of $2$ is discussed in \cref{rem:dl:K-sharp}. A witness of size three or four found along an augmenting path is used only if its digraph has no strongly connected component of three or more vertices in the selected partition. A complete three-vertex component may instead be priced at $6r^3$ by \cref{thm:cubic-resultant}, with internal distinctness on both sides. This extension does not apply to an incomplete three-vertex component. The original criterion holds, for instance, when the connectors between a new witness pair and the others all point one way: the new vertex then lies on no directed cycle, and the kernel factors through one more Gauss operator. Part~(d) keeps inside the norm a bounded multiplier that depends on one endpoint of each of the two pairs of a matching; a third character $\chi(\varsigma_{12}(y_2-x_1))$ or $\chi(\varsigma_{21}(y_1-x_2))$ has modulus at most one and may be absorbed into $F_{\rm mid}$, so the three-edge paths are covered too. In the applications the other coordinates of a larger witness are fixed first and the multipliers may depend on them; the score multipliers of the positive roots are of this form (\cref{sec:positive-roots}). No Schur-multiplier bound for a signed kernel is used. \end{remark} \subsection{A bound for each class \texorpdfstring{$\mathcal C(P,A)$}{C(P,A)}}\label{subsec:extraction:extraction} A class is bounded in four steps. (1)~Its character sum is written as the witness kernel times the nonnegative factors $1+\chi_e$ of the free pairs. (2)~One conditions on the labels of a vertex cover. (3)~The witness labels then have a bounded density, and their kernel is bounded by \cref{lem:matching:kernel}. (4)~The remaining labels are integrated one vertex at a time, each contributing its vertex factor $F_v$ of \cref{def:extraction:records}, with an additional second-order term when a label coincides with a fixed label of the other row. The definitions below record exactly the choices (witness, cover, orders) and the factor contributed by each non-witness vertex. \begin{definition}[Records of a class (extraction data)]\label{def:extraction:records} Let $\mathcal C=\mathcal C(P,A)$ be a class with free pairs $F$, a witness of size $k$ with sets $V\subseteq X$, $W\subseteq Z$, and a cover $(C_x,C_z)$ with integrated sets $U_x$, $U_z$ (\cref{def:extraction:witness}). Fix orders of the four sets $U_x$, $U_z$, $C_x$, $C_z$. Witness, cover and orders form a \emph{record} of $\mathcal C$ (extraction data, not a record in the sense of \cref{subsec:intro:glossary}). For a \emph{non-witness vertex} $v\in(X\setminus V)\cup(Z\setminus W)$ define $t_v$, the set $H_v$ of its \emph{free partners}, $h_v=|H_v|$ and $s_v=t_v+h_v$: \begin{itemize} \item $u\in U_x$: $t_u$ is the number of $G^+$-neighbours of $u$ in $V\cup C_x$ or earlier in $U_x$, and $H_u=\{b:(u,b)\in F\}$; \item $u\in U_z$: $t_u$ is the number of $G^+$-neighbours of $u$ in $W\cup C_z$ or earlier in $U_z$, and $H_u=\{a:(a,u)\in F\}$; \item $b\in C_z$: $t_b$ is the number of $G^+$-neighbours of $b$ earlier in $C_z$, and $H_b=\{a:(a,b)\in F\}$ (all free pairs at $b$, also those from $V$); \item $a\in C_x$: $t_a$ is the number of $G^+$-neighbours of $a$ earlier in $C_x$, and $H_a=\{b:(a,b)\in F\}$. \end{itemize} Viewed in $U^+$, $H_v\subseteq N(v)$, by the symmetry of $N$; and by \textup{(VC$_k$)}, $H_u\subseteq C_z$ for $u\in U_x$ and $H_u\subseteq C_x$ for $u\in U_z$. Thus $t_v\le d^0_v$, $h_v\le r_v$ and $s_v\le d_v\le\Delta$. Put $t_V=e(V)+e(V,C_x)$ and $t_W=e(W)+e(W,C_z)$, let $f_V$ and $f_W$ be the numbers of free pairs with $x$-endpoint in $V$ and with $x'$-endpoint in $W$, and let $\mathrm{ex}(\mathcal C)=t_V+t_W+f_V+f_W$ be the \emph{exponent} of the record. With the \emph{merge counts} (for the merged roots of \cref{lem:extraction-merged-count} below, not the merges of \cref{sec:completion-repair}) \[ \mathrm{mg}(j,i)=\#\{i'\in\operatorname{Adj}(i):j\in N(i')\},\qquad c^U(j,i)=\#\{u\in\operatorname{Adj}(j):u\in N(i)\}\qquad(i,j\in U^+), \] the \emph{vertex factors} of the record are, with Iverson brackets, \begin{align*} F_u&=\frac{1+e_{s_u}(p,n)+r^22^{s_u}\sum_{b\in C_z}2^{c^U(u,b)-[b\in H_u]}} {1-e_{t_u}(p,n)}&&(u\in U_x),\\ F_u&=\frac{1+e_{s_u}(p,n)+r^22^{s_u}\sum_{a\in C_x}2^{c^U(u,a)-[a\in H_u]}} {1-e_{t_u}(p,n)}&&(u\in U_z),\\ F_b&=\frac{1+e_{s_b}(p,2n)+r^22^{s_b}\sum_{j\in U^+} 2^{\mathrm{mg}(j,b)+c^U(j,b)-[j\in H_b]}}{1-e_{t_b}(p,n)}&&(b\in C_x\cup C_z). \end{align*} The brackets record that the free factor of a pair whose two labels coincide is $1+\chi(0)=1$. There are exactly $2(n-k)$ non-witness vertices, hence $2(n-k)$ vertex factors. A class may carry several records; each choice is made once, independently of $p$. \end{definition} \begin{lemma}[Counts with merged roots]\label{lem:extraction-merged-count} Let $\beta_1,\dots,\beta_t\in\Fp$ be distinct, let $\gamma_1,\dots,\gamma_h\in\Fp$ be distinct, let $s_1,\dots,s_t,s'_1,\dots,s'_h\in\{\pm1\}$, and let $\mathcal X\subseteq\Fp$ contain all $\beta_i$ and $\gamma_l$. Let $\mu_{\rm m}=\#\{(i,l):\beta_i=\gamma_l\}$, the number of \emph{merged} roots. Then for every $n'\ge0$ \[ \sum_{\substack{y\in\Fp\setminus\mathcal X\\ \chi(y-\beta_i)=s_i\ \forall i}} \ \prod_{l=1}^h\bigl(1+s'_l\chi(y-\gamma_l)\bigr) \ \le\ p\,2^{-t}2^{\mu_{\rm m}}\bigl(1+e_{t+h-\mu_{\rm m}}(p,n')\bigr) \ \le\ p\,2^{-t}2^{\mu_{\rm m}}\bigl(1+e_{t+h}(p,n')\bigr). \] \end{lemma} \begin{proof} For $y\notin\mathcal X$ every factor $1+s'_l\chi(y-\gamma_l)$ is $0$ or $2$, so the sum is $2^h$ times the number of $y\notin\mathcal X$ satisfying the $t+h$ conditions $\chi(y-\beta_i)=s_i$ and $\chi(y-\gamma_l)=s'_l$. Since the $\beta_i$ are distinct and the $\gamma_l$ are distinct, the merged roots pair one $\beta_i$ with one $\gamma_l$. Two conditions at the same root are identical or incompatible; in the second case the sum is $0$. Otherwise the conditions are $t+h-\mu_{\rm m}$ conditions with distinct roots, all in $\mathcal X$, and by \cref{lem:extension}\ref{it:ext:upper} and \ref{it:et:compare} their solution set has at most $p2^{-(t+h-\mu_{\rm m})}(1+e_{t+h-\mu_{\rm m}}(p,n'))$ elements. Multiply by $2^h$; the second inequality holds because $e_t(p,n')$ is nondecreasing in $t$ \ref{it:et:poly}. \end{proof} \begin{lemma}[Cover rows]\label{lem:extraction-rows} Assume \textup{(S1)} at $p$. Let $C\subseteq U^+$ be a set of $x'$-vertices with an order, let $x\in\mathcal I^+$ and $H\subseteq\{(a,b)\in E_\times:b\in C\}$. For $b\in C$ let $t_b$ be the number of $G^+$-neighbours of $b$ earlier in $C$, $H_b=\{a:(a,b)\in H\}$, $h_b=|H_b|$, $s_b=t_b+h_b$, and let $F_b(H)$ be the expression of $F_b$ in \cref{def:extraction:records} with these counts and these sets $H_b$. Let $\mu_C$ be the law of $x'_C$ for $x'\sim\mu$, and $\kappa_C(x,c')=\sum_{b\in C}\sum_{i\in U^+}c^U(i,b)\one[c'_b=x_i]$. Then \[ \E_{c'\sim\mu_C}\Bigl[\prod_{(a,b)\in H}\bigl(1+\chi(\varsigma_{ab}(c'_b-x_a))\bigr) \,2^{\kappa_C(x,c')}\Bigr]\ \le\ R_{U^+\setminus C}\prod_{b\in C}F_b(H). \] \end{lemma} \begin{proof} Call the integrand $\Pi(c')\ge0$. \emph{Step 1 (reference law).} Let $\lambda_C=\lambda_p(G^+[C])$. By \cref{lem:graphs:vertex}\ref{it:vertex:subset} the density of $\mu_C$ with respect to $\lambda_C$ takes values in an interval $[c_0,R_{U^+\setminus C}c_0]$; since it has mean one, $c_0\le1$ and the density is at most $R_{U^+\setminus C}$. So it suffices to show $\E_{\lambda_C}\Pi\le\prod_{b\in C}F_b(H)$. \emph{Step 2 (lower count).} By \cref{lem:graphs:sequential}\ref{it:seq:count} with the error pair of the setting, no anchors and the given order, \[ |\operatorname{Inj}_p(G^+[C])|\ge\prod_{b\in C}p2^{-t_b}\bigl(1-e_{t_b}(p,n)\bigr). \] Write $\Pi(c')=\prod_b\omega_b(c'_b)$ with \[ \omega_b(y)=\prod_{a\in H_b}\bigl(1+\chi(\varsigma_{ab}(y-x_a))\bigr)\cdot 2^{\sum_ic^U(i,b)\one[y=x_i]}. \] \emph{Step 3 (merge weights).} Call $b$ \emph{coincident} if $c'_b=x_{j(b)}$ for some (unique) $j(b)\in U^+$. A \emph{merge at $b$} is a pair $(b',a)$ with $b'$ earlier than $b$, $b'\sim b$, $a\in H_b$ and $c'_{b'}=x_a$; let $\mu_b=\mu_b(c'_{1$, and let $C_k(Q)$ be the sum over the classes of $\mathfrak P$ with witness size $k$ of $2^{\mathrm{ex}^\star(\mathcal C)/2}R_{\rm full}^2(1-\hat e)^{-k}\prod_u\mathsf f_{\rm m}(s_u)^{1/2}\prod_b\mathsf f_\varrho(s_b)^{1/2}$, evaluated at $r=Q^{-1/2}$. Then for every prime $p\ge Q$ \[ \norm{T_{\rm ns}}_{L^2(\mu)}\le\sum_{k\in\mathcal K_{\rm w}}C_k(Q)\,p^{-k/2}. \] Under the condition \eqref{eq:monotone-signature} the same holds when $C_k(Q)$ is computed from stored numbers $s'_v$ with $s_v\le s'_v\le\Delta$. \end{enumerate} \end{corollary} \begin{proof} (a) Since $t_v\le d^0_v\le\Delta^+$ and $e_t(p,n)$ is nondecreasing in $t$, $1-e_{t_v}(p,n)\ge1-\hat e$. Let $u\in U_x$. As $H_u\subseteq C_z$, the special sum of $F_u$ is \[ \sum_{b\in C_z}2^{c^U(u,b)-[b\in H_u]} =\sum_{b\in C_z}w^{\rm m}_{ub}-\frac12\sum_{b\in H_u}w^{\rm m}_{ub} \le\sum_{b\in U^+}w^{\rm m}_{ub}-\frac12\sum_{b\in H_u}w^{\rm m}_{ub}. \] The set $H_u\subseteq N(u)$ has $h_u=s_u-t_u\ge s_u-d^0_u$ elements, hence at least $h^0_u(s_u)$, so its weights add up to at least $\sigma^{\rm m}_u(s_u)$; and $d_u\ge s_u$. So the special sum is at most $\mathsf S_{\rm m}(s_u)$, and $F_u\le\mathsf f_{\rm m}(s_u)$. For $u\in U_z$ the same argument applies with $C_x$, and for a cover vertex $b$ with the weights $w^\varrho_{bj}$ and $H_b\subseteq N(b)$, $|H_b|=s_b-t_b\ge h^0_b(s_b)$; this gives $F_b\le\mathsf f_\varrho(s_b)$. Finally $2^\beta=2^{2\beta/2}$. Under this condition the numerators of $\mathsf f_{\rm m}(s)$ and $\mathsf f_\varrho(s)$ are nondecreasing in $s$, since $e_s(p,n)$ and $e_s(p,2n)$ are (\ref{it:et:poly}) and $r^22^s\mathsf S(s)$ is by \eqref{eq:monotone-signature}, while the denominator does not depend on $s$; so $\mathsf f(s_v)\le\mathsf f(s'_v)$. (b) (S1) at $Q$ implies (S1) at every prime $p\ge Q$ (\cref{def:spec:data}). By the triangle inequality over $\mathfrak P$ and (a), $\norm{T_{\rm ns}}\le\sum_{\mathcal C\in\mathfrak P}r^{k_{\mathcal C}}\varphi_{\mathcal C}(r)$, where $\varphi_{\mathcal C}(r)$ is the coefficient of $r^{k_{\mathcal C}}$ in (a) as a function of $r$. The count errors $e_s(p,n)$, $e_s(p,2n)$ and $r^2$ are polynomials in $r$ with nonnegative coefficients, and on $(0,Q^{-1/2}]$ every $e_t(p,n')$ with $t\le\Delta$, $n'\le2n$ is below one; so $\varphi_{\mathcal C}$ is admissible by \cref{lem:majorant}(i),(ii) (quotients $1/(1-\varphi)$ and $(1+\varphi)/(1-\varphi)$, products and square roots). Since the records are fixed, $\varphi_{\mathcal C}(p^{-1/2})\le\varphi_{\mathcal C}(Q^{-1/2})$ by \cref{lem:majorant}(a), and summing over the classes of each witness size gives the claim. With stored numbers $s'_v$ every class bound of (a) only grows, and the same argument applies. \end{proof} For a fixed partition with fixed records, the coefficients $C_k(P)$ between two evaluation points $P_01$ at which \textup{(S1)} holds let $C_k(P)$ be the coefficients of \cref{cor:extraction-leaf}(b), and put $M(P)=R_{\rm full}(P)^2(1-\hat e(P))^{-n}$, both evaluated at $r=P^{-1/2}$. Then $C_k=M D_k$, where $D_k$ is a finite positive sum of products of square roots of the numerators of $\mathsf f_{\rm m}$ and $\mathsf f_\varrho$, and $M$, $D_k$ and $C_k$ are nonincreasing functions of $P$ and log-convex functions of $\log P$. Consequently, if $P_01$, then at every prime $p\ge P$ the quantities $D_1/r^2$, $D_{\ge2}/r^4$, $D_{\rm ord}/r^2$ and $D_{\rm nat}/r^2$ are at most their values at $P$, and so is the tail of \textup{(c)} divided by $r^4$ if $\Xi0$, $\norm{M(i)}\le\mathsf k$ if and only if \begin{equation}\label{eq:conditional-star-gate} \begin{pmatrix}\mathsf k^2I-AA^*&\mathsf kD\\ \mathsf kD^*&\mathsf k^2I-BB^*\end{pmatrix} \succeq0 . \end{equation} \item Let $\beta_\chi$ bound $|\E_{\nu_i}\chi(t-x_i)|$ and $|\E_{\nu'_j}\chi(t-y_j)|$ for all $i$, $j$ and $t\in\Omega$. Let $\mathsf d_{\rm L}$ and $\mathsf d_{\rm R}$ be the square roots of the largest row sum times the largest column sum of the nonnegative $X\times Y$ matrices with the entries $(1+\beta_\chi)^{|N_X(i)|-1}-1$, respectively $(1+\beta_\chi)^{|N_Y(j)|-1}-1$, where $D_{ij}\ne0$, and zero elsewhere, and $\mathsf d_1=\mathsf d_{\rm L}+\mathsf d_{\rm R}$; with $m_{ii'}=|N_X(i)\cap N_X(i')|$ put \[ \mathsf e_{\rm L}^2=\max_{i\in X}\sum_{i'\in X}\sum_{s=2}^{m_{ii'}}\binom{m_{ii'}}s \bigl((1+\beta_\chi)^{|N_X(i)|-s}-1\bigr)\bigl((1+\beta_\chi)^{|N_X(i')|-s}-1\bigr), \] let $\mathsf e_{\rm R}$ be defined likewise with $N_Y$, and put $\mathsf e=\max(\mathsf e_{\rm L},\mathsf e_{\rm R})$ and $\mathsf e_\star=\frac12\bigl(\mathsf d_1+\sqrt{\mathsf d_1^2+4\mathsf e^2}\bigr)$. Then $T_\star=\kappa r\,\mathcal F_XM(\Phat)\mathcal F_Y^*+T_{\rm mean}$, with contractions $\mathcal F_X\colon\mathcal H^X\oplus\mathcal H^{\mathcal S_X}\to L^2_0(\nu_X)$, where $\mathcal S_X=\{S\subseteq X:|S|\ge2\}$, and $\mathcal F_Y$ likewise with $Y$ in place of $X$, built from $\nu_X$, respectively $\nu_Y$, alone (defined in the proof) and $\norm{T_{\rm mean}}\le\kappa r\mathsf e_\star$. Hence $\norm{T_\star}\le\kappa r(\norm{M(i)}+\mathsf e_\star)$, and under (a) $\norm{T_\star}\le\kappa r(\mathsf k+\mathsf e_\star)$. No invariance of the coordinate laws is used. \item \emph{Decay.} Let $\kappa_0\ge\kappa$ and $0<\omega_s\le1$ ($s\ge2$) satisfy $\kappa_0\omega_s^2\ge\min\{\kappa_0,1+\nu_\chi^s/r^2\}$, where $\nu_\chi$ bounds $|\operatorname{Cov}_\nu(\chi(t-x),\chi(t'-x))|$ for every coordinate law $\nu$ and all distinct $t,t'\in\Omega$ (if $\omega_s=1$ for every $s\ge2$ no bound on $\nu_\chi$ is needed; an individual $s$ with $\omega_s<1$ uses the bound at that $s$). Let $A_\omega$, $B_\omega$ be $A$, $B$ with every column of a set $T$, respectively $S$, multiplied by $\omega_{|T|}$, respectively $\omega_{|S|}$, and let $M_\omega$ be built from them. Then (b) holds with $\kappa_0$, $M_\omega$ and contractions $\mathcal F^\omega_X$, $\mathcal F^\omega_Y$ in place of $\kappa$, $M$, $\mathcal F_X$, $\mathcal F_Y$; so \eqref{eq:conditional-star-gate} for $A_\omega$, $B_\omega$ gives $\norm{T_\star}\le\kappa_0r(\mathsf k+\mathsf e_\star)$. If $\kappa$ and $\nu_\chi/r$ are admissible functions of $r$ (\cref{lem:majorant}) and rational $\kappa_0$, $\omega_s$ satisfy these conditions at a threshold $p_0$, they satisfy them at every prime $p\ge p_0$. \end{enumerate} \end{proposition} \begin{proof} \emph{Centred feature maps.} (The maps $U_\nu$ and $W_S$ below are the \emph{feature maps}; $\mathcal F_X,\mathcal F_Y$ are assembled from them.) For a coordinate law $\nu$ on $\Fp$ with density $\rho\le\kappa$ let $\iota_\nu\colon L^2(\Fp)\to L^2(\nu)$ be the evaluation $f\mapsto f$; then $\norm{\iota_\nu f}^2_\nu=\E\rho |f|^2\le\kappa\norm f^2$ and $\iota_\nu^*g=\rho g$. The \emph{centred evaluation} $U_\nu=P_0\iota_\nu|_{\mathcal H}\colon\mathcal H\to L^2_0(\nu)$ has norm at most $\sqrt\kappa$; since $P_0\iota_\nu\one=0$, $P_0\iota_\nu=U_\nu P_{\mathcal H}$, with $P_{\mathcal H}$ the projection of $L^2(\Fp)$ onto $\mathcal H$; and for $g\in L^2_0(\nu)$, $U_\nu^*g=\rho g$ is a mean-zero function supported in $\supp\nu\subseteq\Omega$. Put $m_\nu(t)=\E_{x\sim\nu}\chi(t-x)$ and $\phi_\nu(t,x)=\chi(t-x)-m_\nu(t)$, so that $\E_{x\sim\nu}\phi_\nu(t,x)=0$. For $S\subseteq X$ with $|S|\ge2$ let $W_S\colon L^2(\Fp)\to L^2(\nu_X)$, $(W_Sf)(x)=\E_tf(t)\prod_{i\in S}\phi_{\nu_i}(t,x_i)$, and define $W'_T$ for $T\subseteq Y$ likewise with the laws $\nu'_j$. Write $U_i=U_{\nu_i}$ and $U'_j=U_{\nu'_j}$, their outputs read as functions of $x_i$ and of $y_j$. \emph{Step 1 (the contractions $\mathcal F_X,\mathcal F_Y$).} The product law gives the orthogonal decomposition $L^2(\nu_X)=\bigoplus_{R\subseteq X}H_R$, where $H_R$ consists of the functions of $x_R$ whose conditional mean in every coordinate of $R$ vanishes; $U_i$ maps into $H_{\{i\}}$ and $W_S$ into $H_S$. By independence, $\ip{W_Sf}{W_Sf'}=\E_{t,t'}\overline{f(t)}f'(t')\prod_{i\in S}\Gamma_i(t,t')$ with $\Gamma_i(t,t')=\E_{x\sim\nu_i}\phi_{\nu_i}(t,x)\phi_{\nu_i}(t',x)$. Each $\Gamma_i$ is a positive semidefinite kernel with $\Gamma_i(t,t)\le1$, and as an operator relative to the uniform law it is $V_i^*V_i$ with $V_if=\E_t\phi_{\nu_i}(t,\cdot)f(t)=P_0\iota_{\nu_i}Cf$, so $0\preceq\Gamma_i\preceq\kappa r^2I$. For $i_1\in S$, the pointwise product of the $\Gamma_i$ with $i\ne i_1$ is a positive semidefinite kernel with diagonal at most one (Schur product theorem), so by \cref{lem:swapped-rectangle}(b) the kernel $\prod_{i\in S}\Gamma_i$ defines an operator between $0$ and $\kappa r^2I$, and $\norm{W_S}\le\sqrt\kappa\,r$ on all of $L^2(\Fp)$. As the ranges are orthogonal, \[ \mathcal F_X\bigl((f_i)_{i\in X},(g_S)_S\bigr)=\sum_{i\in X}\frac{U_if_i}{\sqrt\kappa} +\sum_S\frac{W_Sg_S}{\sqrt\kappa\,r} \] is a contraction from $\mathcal H^X\oplus\mathcal H^{\mathcal S_X}$ into $L^2_0(\nu_X)$, $\mathcal S_X$ the set of the $S\subseteq X$ with $|S|\ge2$; $\mathcal F_Y$ is built in the same way from the $U'_j$ and the $W'_T$. \emph{Step 2 (exact supports).} Let $g\in L^2_0(\nu_Y)$, and let $\bar g_j$ be its component in $H_{\{j\}}$. A kernel has \emph{exact support} $R$ in $y$ if, for fixed $x$, it depends only on $y_R$ and has conditional mean zero in each coordinate of $R$. Such a kernel sees only the component of $g$ in $H_R$. \emph{Single pairs:} $\E_y\chi(y_j-x_i)g(y)=\E_b\chi(b-x_i)\rho'_j(b)\bar g_j(b)=(CU'^*_j\bar g_j)(x_i)$, with $U'^*_j\bar g_j\in\mathcal H$; after the output is centred, the pair $(i,j)$ gives $rD_{ij}U_i\Phat U'^*_j$. \emph{Row stars:} since $\chi(-1)=-1$, $\prod_{j\in T}D_{ij}\chi(y_j-x_i)=A_{iT}\prod_{j\in T}\bigl(m_{\nu'_j}(x_i) +\phi_{\nu'_j}(x_i,y_j)\bigr)$. In the expansion, the term with all factors $\phi$ has exact support $T$ and gives, after centring, $A_{iT}P_0\iota_{\nu_i}W'^*_T=A_{iT}U_iP_{\mathcal H}W'^*_T=A_{iT}U_i(W'_T|_{\mathcal H})^*$; the term without a factor $\phi$ is a function of $x_i$ and vanishes on mean-zero $g$; the others, with exact supports $\emptyset\ne T'\subsetneq T$, carry the \emph{complementary means} $\prod_{j\in T\setminus T'}m_{\nu'_j}(x_i)$. \emph{Column stars:} $\prod_{i\in S}D_{ij}\chi(y_j-x_i)=B_{jS}\prod_{i\in S}\bigl(m_{\nu_i}(y_j) +\phi_{\nu_i}(y_j,x_i)\bigr)$; the term with all factors $\phi$ gives $B_{jS}W_SU'^*_j$, the term without a factor $\phi$ has a constant image, which the centring removes, and the others carry complementary means. So $T_\star=T_{\rm pure}+T_{\rm mean}$, where $T_{\rm mean}$ collects the terms with complementary means and \[ T_{\rm pure}=\sum_{i,j}rD_{ij}U_i\Phat U'^*_j+\sum_{i,T}A_{iT}U_i(W'_T|_{\mathcal H})^* +\sum_{j,S}B_{jS}W_SU'^*_j=\kappa r\,\mathcal F_XM(\Phat)\mathcal F_Y^*, \] as one checks block by block. \emph{Step 3 (the pure part).} By \cref{lem:spec:gauss}, $\mathcal H=\mathcal H_+\oplus\mathcal H_-$ with $\Phat=\pm iI$ on $\mathcal H_\pm$, and $M(\Phat)$ acts on the two parts as $M(i)\otimes I$ and as $\overline{M(i)}\otimes I$; so $\norm{M(\Phat)}=\norm{M(i)}$ and $\norm{T_{\rm pure}}\le\kappa r\norm{M(i)}$. The matrix is decomposed before the contractions are applied, so no commutation of $\Phat$ with the features is used. \emph{Step 4 (the gate).} For $\mathsf k>0$, $\norm{M(i)}\le\mathsf k$ if and only if the Hermitian dilation $\begin{psmallmatrix}\mathsf kI&M(i)\\M(i)^*&\mathsf kI \end{psmallmatrix}$ is positive semidefinite. Order its index set as $(X,\mathcal S_X,Y,\mathcal T_Y)$, $\mathcal T_Y$ the sets $T$, and take the Schur complement of its diagonal block $\mathsf kI$ on $(\mathcal S_X,\mathcal T_Y)$: the dilation is positive semidefinite if and only if, by \cref{lem:block-completion}(a), \[ \begin{pmatrix}\mathsf kI-\mathsf k^{-1}AA^*&iD\\-iD^*&\mathsf kI-\mathsf k^{-1}BB^* \end{pmatrix}\succeq0 . \] Multiplying by $\mathsf k$ and conjugating with the unitary $\diag(I,-iI)$ gives \eqref{eq:conditional-star-gate}. This proves (a). \emph{Step 5 (complementary means).} Fix a row centre $i$ and an exact support $T'\ne\emptyset$. The terms of the row stars at $i$ with this support add up to $(-1)^{|T'|}\prod_{j\in T'}D_{ij}\,c(x_i)\prod_{j\in T'}\phi_{\nu'_j}(x_i,y_j)$, where $c(t)=\prod_{l\in N_X(i)\setminus T'}(1-D_{il}m_{\nu'_l}(t))-1$ satisfies $|c|\le(1+\beta_\chi)^{|N_X(i)|-|T'|}-1$ on $\Omega$. Their operator maps $H_{T'}(\nu_Y)$ into $H_{\{i\}}(\nu_X)$: for $|T'|\ge2$ it is $g\mapsto\pm P_0[c\cdot\iota_{\nu_i}W'^*_{T'}g]$, of norm at most $\kappa r\norm c_\infty$ by Step 1, and for $T'=\{j\}$ it is $g\mapsto\pm P_0[c\cdot\iota_{\nu_i}C^*U'^*_j\bar g_j]$, with the same bound, since $\E_{y_j}\phi_{\nu'_j}(t,y_j)\bar g_j(y_j)=(C^*U'^*_j\bar g_j)(t)$. Likewise the column stars at $j$ with exact support $S'$ give an operator from $H_{\{j\}}(\nu_Y)$ into $H_{S'}(\nu_X)$, namely $g\mapsto W_{S'}\iota_{\nu'_j}^*(b\,\bar g_j)$ with $|b|\le(1+\beta_\chi)^{|N_Y(j)|-|S'|}-1$ on $\Omega$, and for $S'=\{i\}$ the same with $P_0\iota_{\nu_i}C$ in place of $W_{S'}$; its norm is at most $\kappa r\norm b_\infty$. Write $L^2_0(\nu_X)=\mathcal V_X\oplus\mathcal W_X$ with $\mathcal V_X=\bigoplus_iH_{\{i\}}$ and $\mathcal W_X=\bigoplus_{|S|\ge2}H_S$, and likewise for $Y$. The norm of an operator matrix between orthogonal sums is at most the norm of the matrix of the norms of its entries. The block $\mathcal V_X\leftarrow\mathcal V_Y$ of $T_{\rm mean}$ has entries $H_{\{i\}}\leftarrow H_{\{j\}}$ of norm at most $\kappa r$ times the sum of the entries of the two matrices of (b), so its norm is at most $\kappa r(\mathsf d_{\rm L}+\mathsf d_{\rm R})$ by Schur's test. The block $\mathcal V_X\leftarrow\mathcal W_Y$ has entries $H_{\{i\}}\leftarrow H_{T'}$ of norm at most $\kappa re_{iT'}$, with $e_{iT'}=(1+\beta_\chi)^{|N_X(i)|-|T'|}-1$ for $T'\subseteq N_X(i)$ and zero otherwise; the squared norm of the matrix $(e_{iT'})$ is the norm of its Gram matrix $(\sum_{T'}e_{iT'}e_{i'T'})_{i,i'}$, at most its largest row sum $\mathsf e_{\rm L}^2$. Likewise the block $\mathcal W_X\leftarrow\mathcal V_Y$ has norm at most $\kappa r\mathsf e_{\rm R}$, and the block $\mathcal W_X\leftarrow\mathcal W_Y$ vanishes, since every star has a singleton centre. So $\norm{T_{\rm mean}}\le\kappa r\norm{\begin{psmallmatrix}\mathsf d_1&\mathsf e\\ \mathsf e&0\end{psmallmatrix}}=\kappa r\mathsf e_\star$, which with Step 3 proves (b). \emph{Step 6 (decay).} The Gram kernel of $W_S\one_\Omega$ is $\one_\Omega(t)\one_\Omega(t')\prod_{i\in S}\Gamma_i(t,t')$, with diagonal at most one and off-diagonal entries of modulus at most $\nu_\chi^{|S|}$; its absolute row sums relative to the uniform law are at most $r^2+\nu_\chi^{|S|}$, and Schur's test gives $\norm{W_S\one_\Omega}^2\le r^2+\nu_\chi^{|S|}$. Since $U'^*_j$ has mean-zero range supported in $\Omega$, $W_SU'^*_j=W_S\one_\Omega P_{\mathcal H}U'^*_j$, the two projections being applied in this order; and since $\iota_{\nu_i}$ sees only $\Omega$, $U_iP_{\mathcal H}W'^*_T=U_iP_{\mathcal H}\one_\Omega W'^*_T=U_i(W'_T\one_\Omega P_{\mathcal H})^*$. By the choice of $\omega_s$, $\norm{W_S\one_\Omega P_{\mathcal H}}\le\sqrt{\kappa_0}\,r\omega_{|S|}$: if $\omega_{|S|}<1$, then $\kappa_0\omega_{|S|}^2\ge1+\nu_\chi^{|S|}/r^2$, and otherwise Step 1 applies. So the maps of Step 1 with $\sqrt{\kappa_0}$ in place of $\sqrt\kappa$ and $W_S\one_\Omega P_{\mathcal H}/(\sqrt{\kappa_0}\,r\omega_{|S|})$ in place of $W_S/(\sqrt\kappa\,r)$, and likewise for $Y$, are contractions $\mathcal F^\omega_X$, $\mathcal F^\omega_Y$, and $T_{\rm pure}=\kappa_0r\,\mathcal F^\omega_XM_\omega(\Phat) \mathcal F^{\omega*}_Y$, while $\norm{T_{\rm mean}}\le\kappa r\mathsf e_\star\le\kappa_0r \mathsf e_\star$. At a prime $p\ge p_0$, $\kappa(p)\le\kappa(p_0)\le\kappa_0$, and $1+\nu_\chi^s/r^2=1+(\nu_\chi/r)^sr^{s-2}$ ($s\ge2$) is at most its value at $p_0$, by admissibility; the gate does not depend on $p$. \end{proof} For an invariant law the same matrix appears in \cref{cor:star-matrix}; under a product law the leaves are centred in their own laws and their means are paid by $\mathsf e_\star$. In the conditional rows of the upper range (\cref{subsec:push:layer72product,subsec:advance:product-rows}) the coordinate laws are the allowed-set laws, $\Omega$ is the complement of the middle labels, $\kappa=2^\varpi/(1-e^-_\varpi(z))$, $\beta_\chi$ is the one-character mean bound and $\nu_\chi$ the covariance bound (display (PR3) in \cref{subsec:advance:product-rows}); in the bands the bound $\min\{C_\star, \kappa_0r(\mathsf k+\mathsf e_\star)\}$ takes the place of the scalar majorant $C_\star$ of \eqref{eq:row-anova-stars} in the correlation bound \eqref{eq:row-anova-actual}. \paragraph{Joint fold and matching rows.} The completion of an upper coordinate bounds its fold row and its matching row jointly, relative to one chart (\cref{lem:five-type}(f)). The two rows have the same allowed sets, so their star parts factor through the same contractions, and the joint bound is one more matrix test. \begin{lemma}[Joint fold and matching rows]\label{lem:joint-rows} Let $p\equiv3\pmod4$, and in the setting of this subsection let $\kappa$ bound the densities of the allowed-set laws $\lambda_i$ relative to the uniform law and $I_0\le\lambda(\mathcal I_{\rm pin})$. Let two sets of signed cross pairs be given, the \emph{fold} row $\rm F$ and the \emph{matching} row $\rm E$, with signed incidence matrices $D_{\rm F},D_{\rm E}\in\{0,\pm1\}^{n\times n}$ ($D_\bullet(i,j)=\varsigma_{ij}$ on the pairs of the row and zero elsewhere) and $D_{\rm E}^{\mathsf T}=-D_{\rm E}$. For $\bullet\in\{{\rm F},{\rm E}\}$ let $K_\bullet$ be the raw kernel relative to $\mu\otimes\mu$ (the indicator that $x([n])\cap y([n])=\emptyset$, times the product over the pairs of $1+\chi_{ij}$), $Z_\bullet=\ip\one{K_\bullet\one}_\mu$ and $\pi_\bullet=K_\bullet\,\mu\otimes\mu/Z_\bullet$. Let $\nu$ be the marginal of $\pi_{\rm E}$, and suppose $d\nu/d\mu\ge e^{-\ell_{\rm E}}$. Relative to $\nu\otimes\nu$ let $T_{\rm F}$ and $T_{\rm E}$ be the densities of $\pi_{\rm F}$ and $\pi_{\rm E}$, and $u_{\rm L}$, $u_{\rm R}$ the densities of the two marginals of $\pi_{\rm F}$ relative to $\nu$, and put $C_{\rm F}=T_{\rm F}-u_{\rm L}\otimes u_{\rm R}$ and $C_{\rm E}=T_{\rm E}-\Jproj$, as operators on $L^2(\nu)$. With $\kappa_0$ and $\omega_s$ as in \cref{prop:conditional-star}(c) for the laws $\lambda_i$ and $\Omega=\Fp\setminus\mathcal M$, put, for $D=D_{\rm F},D_{\rm E}$ and all $S\subseteq[n]$ with $|S|\ge2$, \[ A_D(i,S)=(-1)^{|S|}\omega_{|S|}\prod_{j\in S}D(i,j),\qquad B_D(i,S)=\omega_{|S|}\prod_{j\in S}D(j,i), \] and \[ \mathcal Z=\begin{pmatrix}D_{\rm E}&D_{\rm F}\\-D_{\rm F}^{\mathsf T}&D_{\rm E}\end{pmatrix}, \qquad \mathcal A=\begin{pmatrix}A_{D_{\rm E}}&A_{D_{\rm F}}\\B_{D_{\rm F}}&A_{D_{\rm E}}\end{pmatrix}, \qquad\mathcal G=\mathcal A\mathcal A^*. \] Then $C_{\rm F}$ and $C_{\rm E}$ annihilate the constants on both sides, $C_{\rm E}=C_{\rm E}^*$, and $A_{D_{\rm E}}=B_{D_{\rm E}}$. \begin{enumerate}[label=\textup{(\alph*)}] \item Let $\mathsf k>0$ satisfy \begin{equation}\label{eq:joint-gate} \mathsf k^2I+i\mathsf k\mathcal Z-\mathcal G\succeq0, \end{equation} a Hermitian test of size $2n$, rational of size $4n$ in real form (\cref{rem:realified-gates}). For each row $\bullet$ let $e_\bullet$ bound the norm of the complementary-mean operator $T^\bullet_{\rm mean}$ of \cref{prop:conditional-star}(b) for $D_\bullet$ on $L^2_0(\lambda)$, where $\lambda$ is the product of the allowed-set laws, divided by $\kappa_0r$ (for instance $\mathsf e_\star$ of \cref{prop:conditional-star}(b) for $D_\bullet$); let $S^\star_\bullet\ge\norm{P_0K^{\rm st}_\bullet P_0}$ for the star part $K^{\rm st}_\bullet$ of $K_\bullet$, $N_\bullet\ge\norm{T^\bullet_{\rm ns}} +\norm{T^\bullet_{\rm coll}}$ for its nonstar and collision parts, $\eps_\bullet\ge|Z_\bullet-1|$ with $\eps_\bullet<1$, and $m_\bullet\ge\norm{P_0K_\bullet\one},\norm{P_0K_\bullet^*\one}$, all on $L^2(\mu)$. Then \[ \begin{pmatrix}C_{\rm E}&C_{\rm F}\\C_{\rm F}^*&C_{\rm E}\end{pmatrix} \succeq-\mathfrak k_pI\quad\text{on }L^2(\nu)\oplus L^2(\nu),\qquad \mathfrak k_p=e^{\ell_{\rm E}}\Bigl[\frac{\kappa_0r(\mathsf k+e_{\rm F}+e_{\rm E})}{I_0} +\mathfrak c_{\rm F}+\mathfrak c_{\rm E}\Bigr], \] where $\mathfrak c_\bullet=(\eps_\bullet S^\star_\bullet+N_\bullet)/(1-\eps_\bullet) +m_\bullet^2/(1-\eps_\bullet)^2$. \item Let $\Blk$ be a finite set of primes and, for $p\in\Blk$, let $C_{{\rm F},p}$ and $C_{{\rm E},p}=C_{{\rm E},p}^*$ be operators on $L^2(\nu_p)$ that annihilate the constants on both sides, for instance those of (a) at $p$. Put $C_\Blk=\bigotimes_p(\Jproj_p+C_{{\rm F},p})-\Jproj_\Blk$ and $E_\Blk=\bigotimes_p(\Jproj_p+C_{{\rm E},p})-\Jproj_\Blk$ on $L^2(\bigotimes_p\nu_p)$. They act on each exact prime-support sector $\bigotimes_{p\in S}L^2_0(\nu_p)\otimes\one$ ($\emptyset\ne S\subseteq\Blk$) as $\bigotimes_{p\in S}C_{{\rm F},p}$ and $\bigotimes_{p\in S}C_{{\rm E},p}$, so the joint block of $(E_\Blk,C_\Blk)$ is the direct sum of the joint blocks of the sectors. If $\norm{C_{{\rm F},p}}\le c<1$ and $\norm{C_{{\rm E},p}}\le h<1$ for every $p$, the joint block of every sector with at least two primes is $\succeq-(c^2+h^2)I$; so the joint block of $(E_\Blk,C_\Blk)$ is $\succeq-\max(c^2+h^2,\max_p\mathfrak k'_p)I$ whenever the joint block at each prime $p$ is $\succeq-\mathfrak k'_pI$. \item If moreover $C_{{\rm F},p}=T_{{\rm F},p}-u_{{\rm L},p}\otimes u_{{\rm R},p}$ for a kernel $T_{{\rm F},p}$ of mass one with marginal densities $u_{{\rm L},p}$, $u_{{\rm R},p}$ relative to $\nu_p$, and $U_{\rm L}=\bigotimes_pu_{{\rm L},p}$, $U_{\rm R}=\bigotimes_pu_{{\rm R},p}$ satisfy $\norm{U_{\rm L}-\one},\norm{U_{\rm R}-\one}\le\upsilon$, then $T_{{\rm F},\Blk}=\bigotimes_pT_{{\rm F},p}$ satisfies \[ \norm{T_{{\rm F},\Blk}-U_{\rm L}\otimes U_{\rm R}-C_\Blk}\le(2\upsilon+\upsilon^2) \Bigl[\prod_{p\in\Blk}\bigl(1+\norm{C_{{\rm F},p}}\bigr)-1\Bigr], \] which is at most $(2\upsilon+\upsilon^2)(e^{Nc}-1)$ if $\Blk$ has at most $N$ primes, for an integer $N\ge|\Blk|$, and $\norm{C_{{\rm F},p}}\le c$ for every $p\in\Blk$. \end{enumerate} \end{lemma} \begin{proof} \emph{Preliminaries.} At $p\equiv3\pmod4$ the factor of a pair is $1+\varsigma_{ij}\chi(y_j-x_i)$. The factor of $(i,j)$ in $K_{\rm E}(y,x)$ is $1+\varsigma_{ij}\chi(x_j-y_i)=1+D_{\rm E}(j,i)\chi(y_i-x_j)$, the factor of $(j,i)$ in $K_{\rm E}(x,y)$; so $K_{\rm E}$ is symmetric, $\pi_{\rm E}$ has two equal marginals $\nu$, and $T_{\rm E}$ is a symmetric kernel with marginal densities one; hence $C_{\rm E}=C_{\rm E}^*$ annihilates the constants. As $T_{\rm F}\one=u_{\rm L}$ and $\E_\nu u_{\rm R}=1$, $C_{\rm F}\one=0$, and likewise $C_{\rm F}^*\one=0$. Finally $B_{D_{\rm E}}(i,S)=\omega_{|S|}\prod_{j\in S}(-D_{\rm E}(i,j))=A_{D_{\rm E}}(i,S)$. (a) \emph{The actual chart.} Let $g=d\nu/d\mu=K_{\rm E}\one/Z_{\rm E}$, $g_{\rm L}=K_{\rm F}\one/Z_{\rm F}$ and $g_{\rm R}=K_{\rm F}^*\one/Z_{\rm F}$. Then $T_{\rm F}(x,y)=K_{\rm F}(x,y)/(Z_{\rm F}g(x)g(y))$, $u_{\rm L}=g_{\rm L}/g$ and $u_{\rm R}=g_{\rm R}/g$, so for $f,h\in L^2(\nu)$ \[ \ip f{C_{\rm F}h}_\nu=\E_{\pi_{\rm F}}[\overline{f(x)}h(y)]-\E_\nu[\overline f u_{\rm L}]\,\E_\nu[u_{\rm R}h] =\ip f{(K_{\rm F}/Z_{\rm F}-g_{\rm L}\otimes g_{\rm R})h}_\mu, \] and likewise $\ip f{C_{\rm E}h}_\nu=\ip f{(K_{\rm E}/Z_{\rm E}-g\otimes g)h}_\mu$. So the quadratic form of the joint block at $(f,h)$ is that of the self-adjoint operator $\mathbb K$ on $L^2(\mu)^2$ with the diagonal entries $K_{\rm E}/Z_{\rm E}-g\otimes g$ and the off-diagonal entries $K_{\rm F}/Z_{\rm F}-g_{\rm L}\otimes g_{\rm R}$ and its adjoint, and $\norm f^2_\mu=\E_\nu[|f|^2/g]\le e^{\ell_{\rm E}}\norm f^2_\nu$. Hence $\mathbb K\succeq-cI$ with $c\ge0$ gives the joint block $\succeq-ce^{\ell_{\rm E}}I$. A block operator $\begin{psmallmatrix}X&Y\\Y^*&X\end{psmallmatrix}$ has norm at most $\norm X+\norm Y$, which bounds every error term below. \emph{Centring and normalization.} For a kernel $K$ with $Z=\ip\one{K\one}$ and marginal densities $g_1=K\one/Z$, $g_2=K^*\one/Z$ the exact identity $K/Z-g_1\otimes g_2=P_0KP_0/Z-(g_1-\one)\otimes(g_2-\one)$ holds, and for $K=K_\bullet$ the rank-one term has norm at most $m_\bullet^2/(1-\eps_\bullet)^2$. On $\mathcal I_{\rm pin}\times\mathcal I_{\rm pin}$, $K_\bullet=\one\otimes\one+K^{\rm st}_\bullet+T^\bullet_{\rm ns}-T^\bullet_{\rm coll}$, the expansion of \cref{lem:spec:expansion} with the collision part of \cref{prop:pinned-collision}; so $P_0K_\bullet P_0/Z_\bullet=P_0K^{\rm st}_\bullet P_0+(Z_\bullet^{-1}-1)P_0K^{\rm st}_\bullet P_0+Z_\bullet^{-1}P_0(T^\bullet_{\rm ns}-T^\bullet_{\rm coll})P_0$, and the last two terms have norm at most $(\eps_\bullet S^\star_\bullet+N_\bullet)/(1-\eps_\bullet)$. Hence $\mathbb K\succeq\mathbb K^{\rm st}-(\mathfrak c_{\rm F}+\mathfrak c_{\rm E})I$, where $\mathbb K^{\rm st}$ is the joint block of the operators $P_0K^{\rm st}_\bullet P_0$. \emph{Restriction.} Both rows have the law $\mu=\lambda(\cdot\mid\mathcal I_{\rm pin})$, and $P=\lambda(\mathcal I_{\rm pin})\ge I_0$. By \cref{lem:restriction}(a), with the isometry $\iota f=\one_{\mathcal I_{\rm pin}}f/\sqrt P$, which preserves centring, $\ip F{\mathbb K^{\rm st}F}=\ip{\iota F}{\mathbb T\iota F}/P$ for $F\in L^2_0(\mu)^2$, where $\mathbb T$ is the joint block, on $L^2_0(\lambda)^2$, of the operators $T^\bullet_\star$ of \cref{prop:conditional-star} for $\nu_X=\nu_Y=\lambda$ and $D=D_\bullet$; and $\mathbb K^{\rm st}$ vanishes on the constants. So $\mathbb T\succeq-c'I$ gives $\mathbb K^{\rm st}\succeq-(c'/I_0)I$. \emph{Pure stars.} By \cref{prop:conditional-star}(b),(c), $T^\bullet_\star=\kappa_0r\,\mathcal FM_\bullet(\Phat)\mathcal F^*+T^\bullet_{\rm mean}$, with one contraction $\mathcal F=\mathcal F^\omega_X=\mathcal F^\omega_Y$ for both rows and both laws (it depends only on $\lambda$; take all sets $S\subseteq[n]$, $|S|\ge2$), with $M_\bullet$ built from $D_\bullet$, $A_{D_\bullet}$ and $B_{D_\bullet}$, and with $\norm{T^\bullet_{\rm mean}}\le\kappa_0re_\bullet$. So $\mathbb T=\kappa_0r(\mathcal F\oplus\mathcal F)\mathbb M(\mathcal F\oplus\mathcal F)^* +\mathbb T_{\rm mean}$ with $\norm{\mathbb T_{\rm mean}}\le\kappa_0r(e_{\rm E}+e_{\rm F})$, where $\mathbb M$ has the diagonal entries $M_{\rm E}(\Phat)$ and the off-diagonal entries $M_{\rm F}(\Phat)$ and $M_{\rm F}(\Phat)^*$. As $\Phat^*=-\Phat$, $M_{\rm F}(\Phat)^*$ has the singleton block $-D_{\rm F}^{\mathsf T}\otimes\Phat$, the block $B_{D_{\rm F}}\otimes I$ from the sets to the singletons and $A_{D_{\rm F}}^*\otimes I$ from the singletons to the sets; and $D_{\rm E}^{\mathsf T}=-D_{\rm E}$, $A_{D_{\rm E}}=B_{D_{\rm E}}$ give $M_{\rm E}(\Phat)^*=M_{\rm E}(\Phat)$. Grouping the singletons of the two copies and the sets of the two copies, \[ \mathbb M=\begin{pmatrix}\mathcal Z\otimes\Phat&\mathcal A\otimes I\\ \mathcal A^*\otimes I&0\end{pmatrix}. \] On $\mathcal H_\pm$ it acts as $\begin{psmallmatrix}\pm i\mathcal Z&\mathcal A\\ \mathcal A^*&0\end{psmallmatrix}\otimes I$; these are complex conjugate Hermitian matrices, $\mathcal Z$ being real and antisymmetric. By \cref{lem:block-completion}(a), eliminating the block $\mathsf kI$, the one with $+i$ is $\succeq-\mathsf kI$ if and only if $\mathsf kI+i\mathcal Z-\mathsf k^{-1}\mathcal G\succeq0$, which is \eqref{eq:joint-gate}. So $\mathbb M\succeq-\mathsf kI$ and $\mathbb T\succeq-\kappa_0r(\mathsf k+e_{\rm F}+e_{\rm E})I$, and the three steps give $\mathfrak k_p$. (b) As $C_{{\rm F},p}$ annihilates the constants on both sides, $\bigotimes_p(\Jproj_p+C_{{\rm F},p})=\sum_{S\subseteq\Blk}\bigotimes_{p\in S}C_{{\rm F},p} \otimes\bigotimes_{p\notin S}\Jproj_p$, the term of $S$ acting on the sector of $S$ and vanishing on the others; the same holds for $E_\Blk$. On a sector with $|S|\ge2$ the joint block is $\succeq-(\norm{\bigotimes_{p\in S}C_{{\rm E},p}}+\norm{\bigotimes_{p\in S}C_{{\rm F},p}})I \succeq-(h^{|S|}+c^{|S|})I\succeq-(h^2+c^2)I$; on a singleton sector it is the joint block at the prime. (c) Expand $T_{{\rm F},\Blk}=\bigotimes_p(u_{{\rm L},p}\otimes u_{{\rm R},p}+C_{{\rm F},p})$ over the sets $S\subseteq\Blk$ of the primes at which the factor $C_{{\rm F},p}$ is taken. The term of $S=\emptyset$ is $U_{\rm L}\otimes U_{\rm R}$, and $C_\Blk$ is the sum of the other terms with the marginal rank $\bigotimes_{p\notin S}u_{{\rm L},p}\otimes u_{{\rm R},p}=a\otimes b$ of the inactive primes replaced by $\Jproj=\one\otimes\one$. Since $\E u_{{\rm L},p}=1$, $\norm{\bigotimes_{p\in A}u_{{\rm L},p}-\one}^2=\prod_{p\in A}\norm{u_{{\rm L},p}}^2-1$ is nondecreasing in $A$, so $\norm{a-\one}\le\upsilon$, and likewise $\norm{b-\one}\le\upsilon$; hence $a\otimes b-\one\otimes\one=(a-\one)\otimes b+\one\otimes(b-\one)$ has norm at most $\upsilon(1+\upsilon)+\upsilon$. Summing $\prod_{p\in S}\norm{C_{{\rm F},p}}$ times this over $S\ne\emptyset$ gives the bound, and $1+x\le e^x$ the last one. \end{proof} \begin{corollary}[The joint fluctuation in a positive row]\label{cor:joint-row-split} In \cref{lem:joint-rows}(b) let $h\ge0$ and $\mathsf k_\Blk\ge h$ satisfy $E_\Blk\succeq-hI$ and $\begin{psmallmatrix}E_\Blk&C_\Blk\\C_\Blk^*&E_\Blk\end{psmallmatrix} \succeq-\mathsf k_\Blk I$ (a bound $\mathsf k$ of the joint block with $\mathsf k0$ lie in one member of $\mathcal S$. Let $T$ be a real symmetric $2n\times2n$ matrix with $T\pm i\mathcal Z\succeq0$, for instance $T=|\mathcal Z|=(-\mathcal Z^2)^{1/2}$. If $\mathsf k>0$ and \begin{equation}\label{eq:joint-potential-gate} \mathsf k^2I_S-\mathsf k\kappa_0T_S-\kappa_0^2\mathcal G_S\succeq0\qquad(S\in\mathcal S), \end{equation} where $X_S$ denotes the principal submatrix of $X$ on $S$, then the conclusion of \cref{lem:joint-rows}(a) holds without \eqref{eq:joint-gate} and with $r\mathsf k/I_0$ in place of $\kappa_0r\mathsf k/I_0$ in $\mathfrak k_p$; all other terms are kept. For rational $T$ and rational gate parameters, both $T\pm i\mathcal Z\succeq0$ and \eqref{eq:joint-potential-gate} are rational tests in real form (\cref{rem:realified-gates}). \end{lemma} \begin{proof} In the proof of \cref{lem:joint-rows}(a) only the bound of the pure part $\mathbb P=\kappa_0r(\mathcal F\oplus\mathcal F)\mathbb M(\mathcal F\oplus\mathcal F)^*$ changes. Let $\Psi_i\colon L^2(\lambda_i)\to L^2(\Fp)$, $g\mapsto\sqrt{\rho_i}\,g$, an isometry onto the functions supported in the allowed set of $i$; then $\Psi_i\iota_{\lambda_i}$ is the multiplication by $\sqrt{\rho_i}$, and $U_{\lambda_i}=\Psi_i^*\Pi_i\sqrt{\rho_i}\,|_{\mathcal H}$, where $\Pi_i=\Psi_iP_0\Psi_i^*$ is an orthogonal projection. Let $D_\rho$ be the multiplication by $\sqrt{\rho_i}$ on the copy of $L^2(\Fp)$ of the coordinate $(c,i)$, extend $\Phat$ by zero to the constants, and let $\mathcal W$ be the higher part of $\mathcal F\oplus\mathcal F$, a contraction. Since the singleton part of $\mathcal F$ is $U_{\lambda_i}/\sqrt{\kappa_0}$, $\mathbb P$ is the compression, by $\Pi$ on the singleton coordinates (followed by $\Psi^*$), of \[ \mathbb S=\begin{pmatrix}rD_\rho(\mathcal Z\otimes\Phat)D_\rho& \sqrt{\kappa_0}\,rD_\rho(\mathcal A\otimes I)\mathcal W^*\\ \sqrt{\kappa_0}\,r\mathcal W(\mathcal A^*\otimes I)D_\rho&0\end{pmatrix}, \] and compressions keep lower bounds; so it suffices that $\mathbb S\succeq-r\mathsf kI$. By \cref{lem:block-completion}(a) on the block $r\mathsf kI$ and $\mathcal W^*\mathcal W\preceq I$, this follows from $r\mathsf kI+rD_\rho(\mathcal Z\otimes\Phat)D_\rho-(\kappa_0r/\mathsf k)D_\rho(\mathcal G\otimes I)D_\rho\succeq0$. On the eigenspaces of $\Phat$ for $i$, $-i$ and $0$ the operator $T\otimes I+\mathcal Z\otimes\Phat$ is $T+i\mathcal Z$, $T-i\mathcal Z$ and $T$, all positive semidefinite (the last by averaging the first two); so $D_\rho(\mathcal Z\otimes\Phat)D_\rho\succeq-D_\rho(T\otimes I)D_\rho$, and it suffices that $\mathsf k^2I-D_\rho((\mathsf kT+\kappa_0\mathcal G)\otimes I)D_\rho\succeq0$. This operator is the multiplication by the matrix function $t\mapsto\mathsf k^2I-D(t)(\mathsf kT +\kappa_0\mathcal G)D(t)$, $D(t)=\diag(\sqrt{\rho_i(t)})$. At each $t$, $D(t)$ vanishes outside a set $S\in\mathcal S$ and $0\preceq D(t)\preceq\sqrt{\kappa_0}I$; as $\mathsf kT+\kappa_0\mathcal G\succeq0$, the matrix $D(t)(\mathsf kT+\kappa_0\mathcal G)D(t)$ is at most $\kappa_0\lambda_{\max}((\mathsf kT+\kappa_0\mathcal G)_S)I\preceq\mathsf k^2I$, by \eqref{eq:joint-potential-gate}. For $T=|\mathcal Z|$, $T\pm i\mathcal Z\succeq0$ because $i\mathcal Z$ is Hermitian with $|i\mathcal Z|=|\mathcal Z|$. \end{proof} \begin{remark}[The pinned rows of the construction]\label{rem:pinned-instances} The conditional rows of \cref{subsec:advance:product-rows} come in six geometries (the other type L, F or E, with one or two layers), each for the two laws F and E. In all twelve there are no edges inside a row, $n=z\in\{3,6,12\}$, and the pin bound is $\varpi\in\{0,1,2,4\}$; in the two geometries with other type F the actual pin numbers are mixed ($\{0,1\}$ and $\{0,2\}$) and are majorized by $\varpi$. The classes are those of the compressed partition, grouped with $\mathfrak q=0$: the integer $\mathfrak b=\mathrm{oc}(\mathcal C)$, at most $1280$, is used exactly, and for the classes of case (A) of \cref{lem:advance:compressed-partition}(b) the better of two covers is taken class by class (a class may carry several records, \cref{def:extraction:records}). The E law of the E geometries has no cross pairs, so its nonstar part vanishes; the other ten rows have $7164$ classes, counted with their kernel constants $c_{\rm ker}(\mathcal C)$. In all twelve the multisets of row and column degrees coincide. Hence $\Delta_{\rm pin}=\varpi+\max_i|N_X(i)|$ and $D_X=D_Y$, and the evaluator, which computes $\Upsilon_X(1-e^{\rm pin}_\varpi)^{-n}(e^{U_Y}-1)$, returns this common value. These facts are read off the row geometry and the stored partitions (\path{research/advance_2026_10_17/sparse/product_rows_all.py} and \path{product_rows_all_parts.json}; the exact grouping is \path{research/advance_2026_10_24/upper/conditional_fine_parts.json}, checked by \path{check_conditional_fine_buckets.py} of the same directory into \path{conditional_fine_parts_review.json}). Rows with internal edges, which would need the merge charges of \cref{lem:matching:extractionk}, do not occur. The fold and matching rows of one geometry have the same pins, which is the hypothesis of \cref{lem:joint-rows}. \end{remark} \paragraph{The forms that the certificates evaluate.} \emph{Nonstar bounds.} For the two root cuts of the upper range ($n=36$, $\Delta^+=10$, $\Delta=20$) the partition is a refinement of the compressed partition with witnesses of sizes $2$, $3$ and $4$, and the nonstar bound is \cref{cor:extraction-leaf}(b) with the graded errors, the free partners of the records (\cref{def:extraction:records}) and the constants of \eqref{eq:leaf-factors}, under the monotone-factor condition \eqref{eq:monotone-signature}. For the direct Route~B criterion (\cref{lem:record:direct-star-inputs}), from $\Pthree$ to $2^{52}$, the coefficients are evaluated at the nineteen points $2^{47},\dots,2^{52}$, $167\cdot2^{40}$ and $j2^{42}$, $j\in\{40,42,43,44,46,48,50,52,56,60,80,96\}$, and between consecutive ones bounded by \cref{lem:logconvex-coefficients}. The Route~A criterion from $2^{52}$ on uses the tables $C_k(Q)$ at $Q=2^{50},2^{52},\dots,2^{60}$, each prime using the table of the largest $Q\le p$; these tables are computed with the coarse errors and the constants $\max_i\sum_jw^{\rm m}_{ij}$, $\max_i\sum_jw^\varrho_{ij}$, which dominate the factors of \eqref{eq:leaf-factors}. The classes are stored as a histogram of signatures (the witness size, $\mathrm{ex}^\star$, and the multiset of the pairs (kind, $s_v$), the kind being $\mathsf f_{\rm m}$ on $U_x\cup U_z$ and $\mathsf f_\varrho$ on $C_x\cup C_z$) with integer multiplicities, $30\,645\,955$ distinct signature rows in all ($17\,286\,284$ for LL20 and $13\,359\,671$ for LL22); every square root of a vertex factor is rounded upward to a multiple of $2^{-48}$, and the integer sums over the histogram are exact. The nonroot caps \ref{it:record:upper-F6} and the route-A twelve-label caps (\cref{sec:middle-reference}) use \cref{cor:extraction-compressed} with $\mathfrak q=0$ on the compressed partition, each vertex summand of $\mathrm{oc}(\mathcal C)$ rounded upward at $2^{-20}$. The conditional rows \ref{it:record:upper-F3} of the bands use \cref{prop:pinned-extraction} with $\mathfrak q=0$ (\cref{rem:pinned-instances}), \cref{prop:pinned-collision} and the star matrices of \cref{prop:conditional-star}(a)--(c), and their joint fold and matching bounds \cref{lem:joint-rows} (for the $\rm L$ rows with \cref{lem:joint-potential}); those of the tail datum (\cref{def:record:upper-bands}) are computed with $\mathfrak q=20$ and the scalar majorant \eqref{eq:row-anova-stars}. Soft kernels (\cref{cor:soft-kernels}) are evaluated with every coefficient $D_e$ replaced by $|D_e|$ on its support $\{e:D_e\ne0\}$ (its \emph{Boolean support}), or on a larger set of pairs containing that support whose admissibility is checked in \cref{app:certificates} (a \emph{certified Boolean supergraph}). \emph{Coincidence bounds.} For the root cuts the Route~B criterion takes the minimum in \cref{lem:oct24-collision}(e) of $D_1+D_{\ge2}$ (with one order for each pair $(i,j)$, one order $\pi_k$ for each $k=2,\dots,9$ chosen at each of the points $2^{47},\dots,2^{52}$, and the tail (c) from $k_0=10$), $D_{\rm ord}$ and $D_{\rm nat}$; a band evaluates this minimum at its start $X$, with the orders chosen at the evaluation point of its band (\cref{cert:upper-root-caps}). The Route~A criterion takes $\min(D_{\rm ord},D_{\rm nat})$. The nonroot caps and the route-A twelve-label caps use $D_{\rm nat}$ of \eqref{eq:collision-natural}, the L20 cut of the middle root the balanced bound of \cref{prop:l20-collisions} (\cref{cor:incident-weights}), sharpened, for the rows in which the principal (root) law is the uniform law, by the protected-subspace compression of \cref{imp:local:collision-gap}, and the product rows \cref{prop:pinned-collision}. \paragraph{Consequences and what to read next.} This section uses the labellings and the extension count with its coarse and graded errors (\cref{lem:extension}, \eqref{eq:graphs:et}, \eqref{eq:graphs:graded}, \ref{it:et:mono}--\ref{it:et:poly}); one-step error pairs, sequential counts, vertex densities and marginal ratios (\cref{def:graphs:error-pair,lem:graphs:sequential,lem:graphs:vertex}); spectral data, their elementary symmetries and the cut kernel (\cref{def:spec:data,lem:spec:elementary,lem:spec:cutkernel}); the positive Schur order (\cref{lem:swapped-rectangle}(b)) and the restriction to an injectivity event (\cref{lem:restriction}(a)); the character expansion, the Gauss operator and the real form of the phase gates (\cref{lem:spec:expansion,lem:spec:gauss,rem:realified-gates}); the four-cycle kernel for uniform probability (\cref{cor:dl:normalized}); and admissible majorants (\cref{lem:majorant}). Three standard facts are used without statement: the Schur product theorem, Schur's test for the norm of a kernel or a matrix, and H\"older's inequality. \space % End sections/16_extraction % Begin sections/17_completion_repair \section{Making a graph law reflection positive, and replacing a law at fixed marginals}\label{sec:completion-repair} \paragraph{What this section proves and how to read it.} A graph law need not be reflection positive: its cut operator can have a negative part of size about $gp^{-1/2}$. This section proves three constructions that, with the spectral caps, produce the objects Theorem~C needs. A \emph{completion} adds four smaller summand types (folds, matchings, merges, constants, with weights in powers of $r=p^{-1/2}$) to make the law reflection positive at every cut. \emph{Polarization} dominates two summands by two others in the $2\times2$ block order. A \emph{replacement at fixed marginals} (called a \emph{repair} in Part~V) reweights a coupling by $1+f(x)+g(y)$ to prescribed one-half marginals with the same support; ``repair'' never means a small perturbation, and a repaired record keeps the actual half marginals of the record it replaces, so differences annihilate constants. Inputs: spectral caps (\cref{sec:spectral}). Outputs: the completion, polarization and repair theorems applied in Part~V. A first reading should follow the chamber geometry and the three statements below; weight calculations are reference material. \begin{enumerate}[label=(\arabic*)] \item \emph{The five-type completion} (\cref{lem:five-type}). Adding to a root law its folds, matchings, merges and constants, with weights in powers of $r=p^{-1/2}$ fixed by four scalar inequalities, gives a law that is reflection positive at every chamber cut; adding one-layer diagonals restores the reserved cut $\iota$. This is (CP1) of \cref{def:cp1} for the middle atoms (\cref{lem:front12:reference}), the upper atoms (\cref{lem:upper-reference-rp}) and the tail atoms (\cref{sec:tail-index}). Its joint form (f) completes rows whose fold and matching kernels are bounded together, in one Gram matrix, with a mean allowance $t_Y>0$ for each row subject to $t_Y\le H^{-1}$ and $M\ge H+t_Y$ (\cref{cor:joint-completion-blocks}); the bands of the upper range use it. \item \emph{Polarization} (\cref{lem:tr:polarization}). At the chamber cut $\vartheta_0$ the two nonaligned fold records are dominated by the two matching records plus a merge correction of one more order in $r$. This is the first-stage order (CP2)(a) of \cref{def:cp2} (\cref{sec:middle-frame}), the matching bridge of the variance credits (\cref{sec:variance}) and, in all degrees, the fold coupon of the mean credit (\cref{prop:record:mean-credit}). \item \emph{Additive marginal repair} (\cref{lem:tr:repair}) with the centred norm of an additive reweighting (\cref{lem:record:additive-cancellation}). A coupling with the required support whose prescribed target marginals are $\mu_X=(1+u)\nu_X$ and $\mu_Y=(1+v)\nu_Y$ with $|u|\le U_X$, $|v|\le U_Y$ (and the $L^2$ bounds of \cref{lem:tr:repair}) is reweighted by $1+f(x)+g(y)$ to a coupling with exactly those marginals and the same support, and its centred conditional norm stays of the same order; the centred correction is bounded in the actual marginal space, with separate symmetric and skew parts and, against a law with the same marginals, without a marginal-variance term (\cref{lem:record:centered-correction}). If a coupling with the prescribed marginals and the required support is at hand, a positive kernel is completed by mixing it in (\cref{cor:markov-completion}). Apart from the matching records of the middle range, whose law keeps the half marginals of the records it replaces without a repair (\cref{lem:record:e-law}), the comparison records of (CP4) of \cref{def:cp4} are such repaired records or finite combinations of them: the signed fold law of the middle range combines three positive components completed through an accepting coupling (\cref{sec:middle-records}); the middle merge repairs use \cref{lem:tr:repair} (\cref{lem:merge-repair}); the upper range uses one-way repairs (imposing edges in one direction only across the reserved cut), dense comparisons repaired by the initial-segment bound of \cref{lem:tr:repair}(g) and a convex mixture of such repairs (\cref{sec:upper-comparison}); and the tail uses one-way repairs (\cref{sec:tail-index}). \end{enumerate} A repaired record keeps the actual half marginals of the record it replaces, and so does a signed combination of such records with total coefficient one; so every record difference annihilates the constants on both sides of the reserved cut. This is what makes the sharp prices, the variance credits and the common mean of Part~V (the empty-support component retained in \cref{lem:record:common-mean}(a)) possible. \Cref{subsec:chamber-geometry} fixes the chamber geometry of the records, which all three statements use. \subsection{How records sit inside chambers (supports and symmetries)}\label{subsec:chamber-geometry} Throughout this section the patterns below act in one chamber coordinate $\Z/6\Z$ (two in \cref{lem:five-type}(d)); all remaining slot data of a configuration are carried by the objects in $\mathfrak X$. We use the rotation $\rot$, the chamber reflections $\vartheta_i(j)=2i-1-j$ with plus halves $H_i=\{i,i+1,i+2\}$ ($\vartheta_{i+3}=\vartheta_i$), and the group $\mathcal G_6$ of \cref{def:slot-array,lem:slot-array}(i): the translations $u\mapsto u+2k$ and the reflections $\vartheta_0,\vartheta_1,\vartheta_2$ ($u\mapsto5-u$, $1-u$, $3-u$). An \emph{object} carries the labels of a finite set $\mathfrak X$, and a \emph{configuration} is $\Psi=(\Psi_u)_{u\in\Z/6\Z}\in\mathfrak X^{\Z/6\Z}$. For a cut $\vartheta=\vartheta_i$ we use the cut matrix $C_\vartheta$, the order $\succeq_\vartheta$ and the cut form of \cref{def:cc:order} on configurations, and write the diagonal cut form at a real function $g$ on $\mathfrak X^{H_i}$ as \[ Q^{\vartheta}_\kappa(g)=\int g(\Psi|_{H_i})\,g\bigl((\Psi\circ\vartheta)|_{H_i}\bigr) \,d\kappa(\Psi)=\ip g{C_\vartheta(\kappa)g},\qquad Q_\kappa=Q^{\vartheta_0}_\kappa . \] For a law $\lambda$ on $\mathfrak X^{H_i}$ the diagonal copy $\operatorname{Diag}_\vartheta(\lambda)$ (\cref{lem:commoncut}(i)) is fixed \emph{samplewise} by $\vartheta$, meaning $\Psi\circ\vartheta=\Psi$ for every configuration $\Psi$ in its support, and its cut form is $\E_\lambda g^2$. \begin{definition}[Patterns and types]\label{def:patterns} For a map $\phi\colon\Z/6\Z\to O$ into a finite set of objects and a law $\lambda$ on $\mathfrak X^O$, $\Pi_\phi(\lambda)$ is the law of the configuration $\omega\circ\phi=(\omega_{\phi(u)})_u$, $\omega\sim\lambda$; we write $\Pi_\phi$ when $\lambda$ is clear. The \emph{patterns}, listed as $(\phi(0),\dots,\phi(5))$, are: \begin{itemize} \item the identity of $\Z/6\Z$ (type $\rm L$, the \emph{root}); \item the three \emph{folds} $F_0=(0,1,2,2,1,0)$, $F_1=(1,0,0,1,2,2)$, $F_2=(2,2,1,0,0,1)$ (type $\rm D$), with $O=\{0,1,2\}$; \item the two \emph{matchings} $E_0=(0,1,1,2,2,0)$ and $E_1=(0,0,1,1,2,2)$ (type $\rm S$), constant on the blocks of the pair partitions $\mathcal P_e=\{\{0,5\},\{1,2\},\{3,4\}\}$ and $\mathcal P_o=\{\{0,1\},\{2,3\},\{4,5\}\}$, whose $k$th blocks are $E_0^{-1}(k)$ and $E_1^{-1}(k)$; \item the six \emph{merges} $G_{sk}=\one[E_s(\cdot)=k]$, $s\in\{0,1\}$, $k\in\{0,1,2\}$ (type $\rm R$), with values in $\{0,1\}$: $G_{00}=(1,0,0,0,0,1)$, $G_{01}=(0,1,1,0,0,0)$, $G_{02}=(0,0,0,1,1,0)$, $G_{10}=(1,1,0,0,0,0)$, $G_{11}=(0,0,1,1,0,0)$, $G_{12}=(0,0,0,0,1,1)$; we write $G_e=G_{00}$ and $G_o=G_{11}$; \item the constant map $0$, counted twice as $C_0$ and $C_1$ (type $\rm C$), so that $\pi_{\rm C}$ in \cref{def:five-type-datum} contains two copies of $\Pi_0(\nu)$ and contributes the term $2a_{\rm C}z^2$ in \cref{lem:five-type}(a). \end{itemize} The types $\rm L,D,S,R,C$ have the \emph{multiplicities} $1,3,2,6,2$ and the \emph{formal degrees} $0,1,1,2,3$, where the formal degree is the exponent of $r$ in the graded weight of \cref{lem:five-type}. \end{definition} The geometry of these patterns is the following finite check. The root graph of the middle reference, with one or two layers, is the \emph{rotation lift} $G_{\rm L}$ below; with two layers its uniform law is the twelve-label root of \cref{sec:middle-reference}, and on the three late middle pieces the root is a positive reweighting of this law, with the same support and the same symmetries (\cref{sec:positive-roots}). \begin{table}[ht] \centering\small \begin{tabular}{@{}llll@{}} \toprule pattern & plus half $(\Psi_0,\Psi_1,\Psi_2)$ & reflected half $(\Psi_5,\Psi_4,\Psi_3)$ & position\\ \midrule $F_0$ & $(\omega_0,\omega_1,\omega_2)$ & $(\omega_0,\omega_1,\omega_2)$ & diagonal\\ $F_1$ & $(\omega_1,\omega_0,\omega_0)$ & $(\omega_2,\omega_2,\omega_1)$ & $\mathcal U\to\mathcal V$\\ $F_2$ & $(\omega_2,\omega_2,\omega_1)$ & $(\omega_1,\omega_0,\omega_0)$ & $\mathcal V\to\mathcal U$\\ $E_0$ & $(\omega_0,\omega_1,\omega_1)$ & $(\omega_0,\omega_2,\omega_2)$ & $\mathcal U\to\mathcal U$\\ $E_1$ & $(\omega_0,\omega_0,\omega_1)$ & $(\omega_2,\omega_2,\omega_1)$ & $\mathcal V\to\mathcal V$\\ $G_{00}=G_e$ & $(\omega_1,\omega_0,\omega_0)$ & $(\omega_1,\omega_0,\omega_0)$ & diagonal on $\mathcal U$\\ $G_{01}$ & $(\omega_0,\omega_1,\omega_1)$ & $(\omega_0,\omega_0,\omega_0)$ & $\mathcal U\to\mathcal Z$\\ $G_{02}$ & $(\omega_0,\omega_0,\omega_0)$ & $(\omega_0,\omega_1,\omega_1)$ & $\mathcal Z\to\mathcal U$\\ $G_{10}$ & $(\omega_1,\omega_1,\omega_0)$ & $(\omega_0,\omega_0,\omega_0)$ & $\mathcal V\to\mathcal Z$\\ $G_{11}=G_o$ & $(\omega_0,\omega_0,\omega_1)$ & $(\omega_0,\omega_0,\omega_1)$ & diagonal on $\mathcal V$\\ $G_{12}$ & $(\omega_0,\omega_0,\omega_0)$ & $(\omega_1,\omega_1,\omega_0)$ & $\mathcal Z\to\mathcal V$\\ $C_0,C_1$ & $(\omega_0,\omega_0,\omega_0)$ & $(\omega_0,\omega_0,\omega_0)$ & diagonal on $\mathcal Z$\\ \bottomrule \end{tabular} \caption{The halves of $\omega\circ\phi$ at $\vartheta_0$, for $\omega=(\omega_0,\omega_1,\omega_2)$, and the corners $\mathcal U=\{(b,y,y)\colon y\ne b\}$, $\mathcal V=\{(y,y,b)\colon y\ne b\}$, $\mathcal Z=\{(b,b,b)\}$ of $\mathfrak X^{H_0}$ in which they lie when the labels $\omega_o$ that occur are distinct. In the position column $\mathcal A\to\mathcal B$ means that the plus half lies in $\mathcal A$ and the reflected half in $\mathcal B$.} \label{tab:corner} \end{table} \begin{table}[ht] \centering\small \begin{tabular}{@{}lccc@{}} \toprule $\alpha$ & $(F_0\circ\alpha,F_1\circ\alpha,F_2\circ\alpha)$ & $\psi_{0,\alpha}$ & $\psi_{1,\alpha}$\\ \midrule $\vartheta_1\colon u\mapsto1-u$ & $(F_1,F_0,F_2)$ & $(0\ 1)$ & $(1\ 2)$\\ $\vartheta_2\colon u\mapsto3-u$ & $(F_2,F_1,F_0)$ & $(0\ 2)$ & $(0\ 1)$\\ $\vartheta_0\colon u\mapsto5-u$ & $(F_0,F_2,F_1)$ & $(1\ 2)$ & $(0\ 2)$\\ $u\mapsto u+2$ & $(F_2,F_0,F_1)$ & $(0\ 1\ 2)$ & $(0\ 1\ 2)$\\ \bottomrule \end{tabular} \caption{Precomposition with the generators of $\mathcal G_6$: $E_s\circ\alpha=\psi_{s,\alpha}\circ E_s$, where $(0\ 1\ 2)$ is the cycle $0\mapsto1\mapsto2\mapsto0$.} \label{tab:reflection} \end{table} \begin{lemma}[Chamber geometry of the records]\label{lem:record:fold-identification} Let $\Blk$ be a finite set of primes and $\Lambda$ a finite set of layers. Let $G_{\rm L}$ be the oriented graph on $\Z/6\Z\times\Lambda$ with the edges $(u,\ell)\to(\rot u,\ell')$ for all $u$ and all $\ell,\ell'\in\Lambda$ (all layer lifts of the six rotation edges $0\to2\to4\to0$ and $1\to5\to3\to1$); let $G_{\rm F}$ be the graph on $\{0,1,2\}\times\Lambda$ with the edges $(0,\ell)\to(2,\ell')$ for all $\ell,\ell'\in\Lambda$, and $G_{\rm E}$ the graph on $\{0,1,2\}\times\Lambda$ without edges. An object carries one label of $X_{\Blk}=\prod_{p\in\Blk}\Fp$ per layer, so $\mathfrak X=X_{\Blk}^\Lambda$. The graph law $\lambda_{\Blk}(G_{\rm L})$ is a law on $\mathfrak X^{\Z/6\Z}$; put $\lambda_{\rm F}=\lambda_{\Blk}(G_{\rm F})$ and $\lambda_{\rm E}=\lambda_{\Blk}(G_{\rm E})$. \begin{enumerate}[label=\textup{(\alph*)}] \item The reflections $u\mapsto k-u$ $(k\in\{1,3,5\})$ and the translation $u\mapsto u+2$ map the edge set of $G_{\rm L}$ onto itself. Hence $\lambda_{\Blk}(G_{\rm L})$ is invariant under $\mathcal G_6$, and at each $\vartheta_i$ it is a coupling of two copies of one half law. \item For $j\in\{0,1,2\}$, $F_j\circ\vartheta_{2j}=F_j$, and $F_j$ maps the points $2j,2j+1,2j+2$ of $H_{2j}$ (indices mod $6$) to $0,1,2$. Hence for every law $\lambda$ on $\mathfrak X^{\{0,1,2\}}$, $\Pi_{F_j}(\lambda)=\operatorname{Diag}_{\vartheta_{2j}}(\lambda^{(j)})$, where $\lambda^{(j)}$ is the law on $\mathfrak X^{H_{2j}}$ which puts the labels of the object $o$ at $2j+o$, $o\in\{0,1,2\}$. We call $\vartheta_{2j}$ the \emph{fold chamber} of $F_j$. \item The subgraph of $G_{\rm L}$ induced on $H_{2j}\times\Lambda$, read in the order $(2j,2j+1,2j+2)$, is $G_{\rm F}$. Hence the half marginal of $\lambda_{\Blk}(G_{\rm L})$ on $H_{2j}$, read in this order, is a law on the support of $\lambda_{\rm F}$, and it does not depend on $j$. \item Let $\Lambda=\{0,1\}$ and let $\iota$ be the layer swap, with plus half the layer $0$. If a law $\lambda$ on $\mathfrak X^O$ is invariant under the swap of the two layer labels of every object, then every image $\Pi_\phi(\lambda)$ is symmetric at $\iota$, and its actual half marginal at $\iota$ is the image under $\phi$ of the layer-zero marginal of $\lambda$. In particular $\Pi_{F_j}(\lambda_{\rm F})$ and $\Pi_{E_s}(\lambda_{\rm E})$ are symmetric at $\iota$; the actual half marginal of the first is $\Pi_{F_j}(m_0)$, where $m_0$ is the law of the layer-zero triple under $\lambda_{\rm F}$, that of the second the uniform law on the ordered triples of labels distinct at every prime of $\Blk$, placed by $E_s$. \item Precomposition with $\alpha\in\mathcal G_6$ permutes the folds, maps $E_s$ to $\psi\circ E_s$ for a permutation $\psi=\psi_{s,\alpha}$ of $\{0,1,2\}$, maps $G_{sk}$ to $G_{s,\psi^{-1}(k)}$, and fixes the constant maps; for the generators the action is that of \cref{tab:reflection}. The fold $F_j$ and the merges $G_e$, $G_o$ are fixed by the following chamber reflections: $F_0$, $G_e$ and $G_o$ by $\vartheta_0$, $F_1$ by $\vartheta_2$, $F_2$ by $\vartheta_4=\vartheta_1$. \item At $\vartheta_0$ the halves of $\omega\circ\phi$ are those of \cref{tab:corner}. The corners $\mathcal U$, $\mathcal V$, $\mathcal Z$ are pairwise disjoint. \end{enumerate} Parts (b), (e) and (f) use only the patterns, and hold for objects with labels in any finite set $\mathfrak X$. \end{lemma} \begin{proof} (a) Under $u\mapsto3-u$ the edges $0\to2$, $2\to4$, $4\to0$ go to $3\to1$, $1\to5$, $5\to3$, and conversely; under $u\mapsto1-u$ they go to $1\to5$, $5\to3$, $3\to1$, and under $u\mapsto5-u$ to $5\to3$, $3\to1$, $1\to5$; the translation by two permutes each of the two directed triangles. Since all layer lifts of every rotation edge are edges, these maps, acting on the first factor, are automorphisms of $G_{\rm L}$, and they generate $\mathcal G_6$. A graph automorphism permutes the injective strict-square labellings at every prime, so it preserves $\lambda_{\Blk}(G_{\rm L})$. A law invariant under $\vartheta_i$ has the same law on its two halves. (b) At the points $2j,2j+1,2j+2$ the fold $F_j$ takes the values $0,1,2$ (for $F_2$ the points are $4,5,0$), and $\vartheta_{2j}(u)=4j-1-u$, that is $5-u$, $3-u$ and $1-u$ for $j=0,1,2$; substitution in the tuples gives $F_j(\vartheta_{2j}u)=F_j(u)$. So every configuration $\omega\circ F_j$ is fixed by $\vartheta_{2j}$, and its plus half carries $\omega_o$ at $2j+o$. (c) Inside $H_{2j}$ the only rotation edge is $2j\to2j+2$: $\rot(2j)=2j+2$, while $\rot(2j+1)=2j-1$ and $\rot(2j+2)=2j+4$ lie outside $H_{2j}$, and the odd position $2j+1$ is joined in $G_{\rm L}$ only to odd positions. With all layer lifts the induced graph is $G_{\rm F}$ in the stated order. The restriction of an injective strict-square labelling of $G_{\rm L}$ to $H_{2j}\times\Lambda$ is one of the induced graph. The translation $u\mapsto u+2j$ maps $H_0$ onto $H_{2j}$ in order and preserves $G_{\rm L}$, so by (a) the half marginal does not depend on $j$. (d) The layer swap commutes with $\omega\mapsto\omega\circ\phi$, so the image of a swap-invariant law is $\iota$-invariant, which is the symmetry of its cut matrix at $\iota$; its plus half is the layer-zero part. The swap is an automorphism of $G_{\rm F}$ (all layer lifts of $0\to2$ are edges) and of $G_{\rm E}$, so $\lambda_{\rm F}$ and $\lambda_{\rm E}$ are swap invariant. Under $\lambda_{\rm E}$ the six labels are uniform among those distinct at every prime, so the layer-zero triple is uniform on the ordered triples of distinct labels. (e) Substitution in the tuples gives \cref{tab:reflection}; for instance $E_0(1-u)=(1,0,0,2,2,1)$, which is $E_0$ with the names $0,1$ exchanged, and $F_1(3-u)=F_1(u)$. Since the generators map each block of $\mathcal P_e$ and of $\mathcal P_o$ onto a block of the same partition, so does every $\alpha\in\mathcal G_6$, and $E_s\circ\alpha=\psi\circ E_s$ for the induced permutation $\psi$ of the block names. Then $G_{sk}(\alpha u)=\one[\psi(E_s(u))=k]=G_{s,\psi^{-1}(k)}(u)$. The last sentence is (b) together with $G_{00}(5-u)=G_{00}(u)$ and $G_{11}(5-u)=G_{11}(u)$. (f) Substitution gives \cref{tab:corner}. If $(b,y,y)=(y',y',b')$ with $y\ne b$ and $y'\ne b'$, then $y'=b$ and $y'=y$, contradicting $y\ne b$; a point of $\mathcal Z$ has three equal entries, so in either form above it has $y=b$ and lies in neither $\mathcal U$ nor $\mathcal V$. Hence the corners are pairwise disjoint. \end{proof} The cut forms of all components at $\vartheta_0$ are read off \cref{tab:corner}: the cut form of every component other than the root and the aligned fold $F_0$ depends on a half-function $g$ only through its restrictions to the corners $\mathcal U$, $\mathcal V$ and $\mathcal Z$. In Part~V the two facts used most are (b), which says that the two-layer fold record is the diagonal copy, at its own chamber, of its induced law, and (d), which identifies its actual half marginal at the reserved cut. \subsection{The five-type completion}\label{subsec:five-type} A labelling law is made positive at a chamber cut in steps of one order of $r=p^{-1/2}$ each. Relative to the diagonal of its own half law, its cut operator is bounded below by $-\delta$ with $\delta$ of order $r$ (the \emph{root envelope}, from the spectral caps). In the graph-law applications that diagonal is supplied by the aligned fold (\cref{lem:record:fold-identification}(b),(c)): a copy of the half law placed symmetrically, which is fixed by the cut and positive there. In \cref{lem:five-type} this is the general root-envelope hypothesis $\Pi_{\rm L}\succeq_{\vartheta_0}-\delta\,\Pi_{F_0}$, with $\Pi_{F_0}$ built from $\pi_{\rm F}$. The aligned fold at one cut is a nonaligned fold at the others, where its form couples the two corners $\mathcal U,\mathcal V$; this coupling is dominated by the matchings up to the kernel errors $e_{\rm F},e_{\rm E}$ of \cref{lem:five-type}(b); those errors, and the mean-zero parts $U^\circ,V^\circ$ of (c), are dominated by the merges, and the linear terms of the merges by the constants. So the five types enter with the formal degrees $0,1,1,2,3$, and the constants may carry degree three although the merges have degree two, because the last condition $a_{\rm C}a_{\rm S}\ge a_{\rm R}^2$ of \cref{lem:five-type}(b) has total degree $3+1=2+2$ in the graded weights. \begin{definition}[Five-type datum]\label{def:five-type-datum} A \emph{five-type datum} on a finite set $\mathfrak X$ consists of \begin{enumerate}[label=\textup{(\roman*)}] \item a probability measure $\nu$ on $\mathfrak X$, the law of the middle object $\omega_1$ in (iii) and (iv) below (the \emph{middle law}), and, for each $b\in\supp\nu$, a probability measure $\nu^b$ on $\mathfrak X$ (the \emph{conditional reference}); \item a symmetric probability measure $\Gamma$ on $\mathfrak X^2$ with $\Gamma(dx\,db)=\nu(db)\nu^b(dx)$; \item an exchangeable probability measure $\pi_{\rm E}$ on $\mathfrak X^{\{0,1,2\}}$ with \[ \pi_{\rm E}(d\omega_0\,d\omega_1\,d\omega_2)=\nu(d\omega_1)\,\nu^{\omega_1}(d\omega_0)\, \nu^{\omega_1}(d\omega_2)\,T_{\rm E}^{\omega_1}(\omega_0,\omega_2); \] \item a probability measure $\pi_{\rm F}$ on $\mathfrak X^{\{0,1,2\}}$ with \[ \pi_{\rm F}(d\omega_0\,d\omega_1\,d\omega_2)=\nu(d\omega_1)\,\nu^{\omega_1}(d\omega_0)\, \nu^{\omega_1}(d\omega_2)\,T_{\rm F}^{\omega_1}(\omega_0,\omega_2); \] \item a probability measure $\pi_{\rm L}$ on $\mathfrak X^{\Z/6\Z}$ invariant under $\mathcal G_6$; \end{enumerate} with nonnegative kernels $T_{\rm E}^b,T_{\rm F}^b$. A kernel $T$ is the operator $Th(x)=\int T(x,y)h(y)\,\nu^b(dy)$ on $L^2(\nu^b)$; norms, inner products, means and the projection $\Jproj$ onto the constants refer to $L^2(\nu^b)$. The \emph{components} of the datum are $\Pi_{\rm L}=\pi_{\rm L}$, $\Pi_{F_j}=\Pi_{F_j}(\pi_{\rm F})$, $\Pi_{E_s}=\Pi_{E_s}(\pi_{\rm E})$, $\Pi_{G_{sk}}=\Pi_{G_{sk}}(\Gamma)$ (the objects $0,1$ of $\Gamma$) and $\Pi_{C_0}=\Pi_{C_1}=\Pi_0(\nu)$; $\pi_t$ is the sum of the components of the type $t$, and for weights $a=(a_{\rm L},a_{\rm D},a_{\rm S},a_{\rm R},a_{\rm C})\ge0$ the \emph{five-type measure} is $\mathcal Q_a=\sum_ta_t\pi_t$. \end{definition} In the applications $\Gamma$ is the two-object marginal of $\pi_{\rm E}$ and $\nu$, $\nu^b$ are its one-object marginal and conditional law (the merges and constants use only some objects of the matching law); then (ii) holds, and $T^b_{\rm E}$, the density of the conditional law of the objects $0,2$ given $\omega_1=b$, is a coupling of $\nu^b$ with itself, $T_{\rm E}^b\one= (T_{\rm E}^b)^*\one=\one$. The fold kernel $T_{\rm F}^b$ contains the density of the middle law of $\pi_{\rm F}$ relative to $\nu$ and those of its conditional outer marginals relative to $\nu^b$, so no equality of the middle laws of the fold and matching laws is assumed. \begin{definition}[Two coordinates]\label{def:two-coordinate-five-type} Let $X$ be a finite set of labels, $\Lambda$ a finite set of layers and $W=\Z/6\Z\times\Z/6\Z\times\Lambda$. Put $O_{\rm L}=\Z/6\Z$ and $O_{\rm F}=O_{\rm E}=\{0,1,2\}$. The types $\rm L,D,S,R,C$ have the \emph{field types} (the named graph $G_{\rm L},G_{\rm F}$ or $G_{\rm E}$ from which the coordinate law is taken; ``field'' here does not refer to $\Fp$) $\mathfrak f({\rm L})={\rm L}$, $\mathfrak f({\rm D})={\rm F}$, $\mathfrak f({\rm S})=\mathfrak f({\rm R})=\mathfrak f({\rm C})={\rm E}$ and the pattern sets $P_{\rm L}=\{{\rm id}\}$, $P_{\rm D}=\{F_0,F_1,F_2\}$, $P_{\rm S}=\{E_0,E_1\}$, $P_{\rm R}=\{G_{sk}\}$, $P_{\rm C}=\{C_0,C_1\}$. Suppose given, for each pair of field types, a probability law $\lambda_{\mathfrak f_0\mathfrak f_1}$ on $X^{O_{\mathfrak f_0}\times O_{\mathfrak f_1} \times\Lambda}$. A \emph{state} is $t=(t_0,t_1)$, of degree $\deg t_0+\deg t_1$. For patterns $\phi=(\phi_0,\phi_1)\in P_{t_0}\times P_{t_1}$ the component $\Pi_{t,\phi}$ is the law of $e_\phi(y)$, where $e_\phi(y)_{(u_0,u_1,\ell)}=y_{\phi_0(u_0),\phi_1(u_1),\ell}$ and $y\sim\lambda_{\mathfrak f(t_0)\mathfrak f(t_1)}$; $\pi_t=\sum_\phi\Pi_{t,\phi}$, and for weights $a_t\ge0$ we put $\mathcal Q=\sum_ta_t\pi_t$. The \emph{row data of the coordinate $0$ at the field type $\mathfrak f'$} are the laws, on the row space $\mathfrak X=X^{O_{\mathfrak f'}\times\Lambda}$, of the families of rows $(y_{o,\cdot,\cdot})_o$ of $y\sim\lambda_{{\rm L}\mathfrak f'}$ (this is $\pi_{\rm L}$), $y\sim\lambda_{{\rm F}\mathfrak f'}$ ($\pi_{\rm F}$) and $y\sim\lambda_{{\rm E}\mathfrak f'}$ ($\pi_{\rm E}$), together with the law $\Gamma$ of the rows $0,1$ and the law $\nu$ of the row $0$ of $\lambda_{{\rm E}\mathfrak f'}$, and the conditional law $\nu^b$ of the row $0$ given that the row $1$ is $b$. The row data of the coordinate $1$ are defined in the same way with the two coordinates exchanged. We write $\vartheta_{c,i}$ for the reflection $\vartheta_i$ in the coordinate $c$. \end{definition} \begin{lemma}[Five-type completion]\label{lem:five-type} Let $(\nu,\nu^b,\Gamma,\pi_{\rm E},\pi_{\rm F},\pi_{\rm L})$ be a five-type datum on $\mathfrak X$, and $a\ge0$ weights. \begin{enumerate}[label=\textup{(\alph*)}] \item \emph{Invariance and cut forms.} $\mathcal Q_a$ is invariant under $\mathcal G_6$. For a real function $g$ on $\mathfrak X^{H_0}$ put $U_b(y)=g(b,y,y)$, $V_b(y)=g(y,y,b)$, $z_b=g(b,b,b)$, $u_b=\E_{\nu^b}U_b$ and $v_b=\E_{\nu^b}V_b$, and let $\E_b$ be the average over $b\sim\nu$. Then \begin{gather*} Q_{\Pi_{F_0}}(g)=\E_{\pi_{\rm F}}g(\omega)^2,\qquad Q_{\Pi_{F_1}}(g)=Q_{\Pi_{F_2}}(g)=\E_b\ip{U_b}{T_{\rm F}^bV_b},\\ Q_{\Pi_{E_0}}(g)=\E_b\ip{U_b}{T_{\rm E}^bU_b},\qquad Q_{\Pi_{E_1}}(g)=\E_b\ip{V_b}{T_{\rm E}^bV_b},\\ Q_{\Pi_{G_e}}(g)=\E_b\|U_b\|^2,\qquad Q_{\Pi_{G_o}}(g)=\E_b\|V_b\|^2,\\ Q_{\Pi_{G_{01}}}(g)=Q_{\Pi_{G_{02}}}(g)=\E_b[z_bu_b],\qquad Q_{\Pi_{G_{10}}}(g)=Q_{\Pi_{G_{12}}}(g)=\E_b[z_bv_b],\qquad Q_{\Pi_{C_k}}(g)=\E_bz_b^2 . \end{gather*} For every $b\in\supp\nu$, every linear operator $T$ on $L^2(\nu^b)$, every $e\ge0$ with $\|T-\Jproj\|\le e$ and all real $\Phi,\Psi\in L^2(\nu^b)$, $\ip\Phi{T\Psi}\ge\E_{\nu^b}\Phi\,\E_{\nu^b}\Psi -e\|\Phi\|\|\Psi\|$. \item \emph{Full-norm criterion.} Suppose that $\|T_{\rm F}^b-\Jproj\|\le e_{\rm F}$ and $\|T_{\rm E}^b-\Jproj\|\le e_{\rm E}$ for every $b\in\supp\nu$, and \[ a_{\rm S}\ge a_{\rm D},\qquad a_{\rm R}\ge e_{\rm F}a_{\rm D}+e_{\rm E}a_{\rm S}, \qquad a_{\rm C}a_{\rm S}\ge a_{\rm R}^2 . \] Then $\mathcal Q_a-a_{\rm L}\Pi_{\rm L}\succeq_{\vartheta_0}a_{\rm D}\Pi_{F_0}$. If moreover the root envelope $\Pi_{\rm L}\succeq_{\vartheta_0}-\delta\,\Pi_{F_0}$ holds and $a_{\rm D}\ge\delta a_{\rm L}$ (no condition if $a_{\rm L}=0$), then $\mathcal Q_a$ is reflection positive at every chamber cut $\vartheta_i$, $i\in\Z/6\Z$. For $r>0$ and the \emph{graded weights} $(w_{\rm L},w_{\rm D}r,w_{\rm S}r,w_{\rm R}r^2,w_{\rm C}r^3)$, with $e_{\rm F}=fr$, $e_{\rm E}=hr$ and $\delta=dr$, the conditions read \[ w_{\rm D}\ge d\,w_{\rm L},\qquad w_{\rm S}\ge w_{\rm D},\qquad w_{\rm R}\ge fw_{\rm D}+hw_{\rm S},\qquad w_{\rm C}w_{\rm S}\ge w_{\rm R}^2 . \] \item \emph{Schur criterion.} Suppose that for every $b\in\supp\nu$ the matching kernel has exact marginals, $T_{\rm E}^b\one=(T_{\rm E}^b)^*\one=\one$, with $\|T_{\rm E}^b-\Jproj\|\le\rho_{\rm E}$, and that the fold kernel $K_b=T_{\rm F}^b$ has the \emph{fold data} \[ m_b:=\ip\one{K_b\one}\in[H^{-1},H],\qquad \|(I-\Jproj)K_b\one\|,\ \|(I-\Jproj)K_b^*\one\|\le\beta,\qquad \|(I-\Jproj)K_b(I-\Jproj)\|\le q_\perp . \] Let $a_{\rm D}>0$, $M=a_{\rm S}/a_{\rm D}$, $s=a_{\rm R}/a_{\rm D}$, $k=a_{\rm C}/a_{\rm D}$, and let $t_Y>0$ (the \emph{mean allowance}) satisfy \[ M\ge H+t_Y,\qquad t_Y\le H^{-1},\qquad s\ge q_\perp+M\rho_{\rm E}+\beta^2/t_Y,\qquad kM\ge s^2 . \] Then $\mathcal Q_a-a_{\rm L}\Pi_{\rm L}\succeq_{\vartheta_0}a_{\rm D}\Pi_{F_0}$, and under the root envelope and $a_{\rm D}\ge\delta a_{\rm L}$ of (b) the measure $\mathcal Q_a$ is reflection positive at every chamber cut. For $t_Y=\frac12$ the conditions follow from $H\le\frac32$, $M\ge2$, $s\ge q_\perp+M\rho_{\rm E}+2\beta^2$ and $kM\ge s^2$. For graded weights, with $h=\rho_{\rm E}/r$ and $f_{\rm al}=(q_\perp+\beta^2/t_Y)/r$, the conditions read $w_{\rm D}\ge d\,w_{\rm L}$, $w_{\rm S}\ge(H+t_Y)w_{\rm D}$, $w_{\rm R}\ge f_{\rm al}w_{\rm D}+hw_{\rm S}$ and $w_{\rm C}w_{\rm S}\ge w_{\rm R}^2$, together with $t_Y\le H^{-1}$. \item \emph{Two coordinates (slice principle).} In the setting of \cref{def:two-coordinate-five-type}, suppose that for each coordinate $c$ and each field type $\mathfrak f'$ the row data of $c$ at $\mathfrak f'$ form a five-type datum, and that for each type $t'$ the five weights $a_t$ of the states $t$ with $t_{1-c}=t'$, as $t_c$ ranges over the five types, satisfy the hypotheses of (b), of (c) or of (f) for the row data of $c$ at $\mathfrak f(t')$, these five weights playing the roles of $a_{\rm L},a_{\rm D},a_{\rm S},a_{\rm R},a_{\rm C}$ there respectively, in each case together with the root envelope and the inequality $a_{\rm D}\ge\delta a_{\rm L}$ of (b) in these roles. Then $\mathcal Q$ is reflection positive at every chamber cut $\vartheta_{c,i}$ of both coordinates. More precisely, for fixed $c$, $t'$ and $\phi'\in P_{t'}$, the sum of the components $a_t\Pi_{t,\phi}$ with $t_{1-c}=t'$ and $\phi_{1-c}=\phi'$ is the image of the five-type measure of these row data under the emission (placement map) $e_{\phi'}\colon\mathfrak X^{\Z/6\Z}\to X^W$, $e_{\phi'}(\Psi)_{(u_0,u_1,\ell)}=\Psi_{u_c}(\phi'(u_{1-c}),\ell)$. \item \emph{The reserved cut (fold pairing).} Let $\Lambda=\{0,1\}$, let $\iota$ be the layer swap, and for a one-layer measure $\kappa$ let $\operatorname{Diag}_\iota(\kappa)$ be the law that carries the same one-layer configuration on both layers. Consider the components of one coordinate (objects carrying one label per layer) or of two coordinates as in (d), and the one-layer components $\Pi^{(1)}$ built in the same way from one-layer laws; let $\pi_{t,j}$ be the sum of the $j$-layer components of the type or state $t$. Suppose that every two-layer component $\Pi$ of $t$ satisfies $\Pi\succeq_\iota-k_tr\operatorname{Diag}_\iota(\Pi^{(1)})$, where $\Pi^{(1)}$ is a fixed one-layer component with the same patterns as $\Pi$ (one such component being fixed for each two-layer component), and let $w_t,v_t\ge0$ with $v_t\ge k_tw_t$ for every $t$. Then \[ \widetilde\mu=\sum_tw_tr^{\deg t}\pi_{t,2} +r\sum_tv_tr^{\deg t}\operatorname{Diag}_\iota(\pi_{t,1})\succeq_\iota0 . \] $\operatorname{Diag}_\iota$ preserves the order $\succeq_\vartheta$ at every chamber cut $\vartheta$; in particular it maps a one-layer measure that is reflection positive at a chamber cut to a measure reflection positive there. Hence if the two-layer data with the weights $w_tr^{\deg t}$ and the one-layer data with the weights $v_tr^{\deg t}$ satisfy the hypotheses of (b), (c), (d) or (f), root envelopes included (for (b) in graded form: $v_{\rm D}\ge d_1v_{\rm L}$, $v_{\rm S}\ge v_{\rm D}$, $v_{\rm R}\ge f_1v_{\rm D}+h_1v_{\rm S}$, $v_{\rm C}v_{\rm S}\ge v_{\rm R}^2$ with the one-layer inputs; all these conditions are homogeneous in $v$), then $\widetilde\mu$ is reflection positive at every chamber cut of the active coordinates and at $\iota$. Finally, if a field law $\lambda$ and its one-layer law $\lambda^{(1)}$ satisfy $\lambda\succeq_\iota-kr\operatorname{Diag}_\iota(\lambda^{(1)})$, then so do their images under every emission $e_\phi$ (in one coordinate, the map $\omega\mapsto\omega\circ\phi$); so components that use only some objects of a field law, the merges and the constants, inherit its bound. A component may also be used with a smaller proved coefficient than $k_t$ in its own order at $\iota$, and $\Pi^{(1)}$ need not be the one-layer marginal of $\Pi$: only the order $\Pi\succeq_\iota-k_tr\operatorname{Diag}_\iota(\Pi^{(1)})$ is used. \item \emph{Joint Schur criterion.} Suppose that for every $b\in\supp\nu$ the matching kernel has exact marginals, as in (c), and the fold kernel has the \emph{joint data} \[ K_b=T_{\rm F}^b=m_b\bigl(\varphi_0\otimes\varphi_2+C_b+R_b\bigr),\qquad m_b\in[H^{-1},H], \] with $\E\varphi_0=\E\varphi_2=1$ (both $\varphi_0$ and $\varphi_2$ depend on $b$, the index being suppressed) and $\|\varphi_o-\one\|\le\upsilon$ ($o=0,2$), where $\varphi_0\otimes\varphi_2$ is the kernel $\varphi_0(x)\varphi_2(y)$ and the kernels $C_b$, $R_b$ annihilate the constants on both sides, with $\|R_b\|\le\eps_{\rm T}$; and that, with $E_b=\frac12(T_{\rm E}^b+(T_{\rm E}^b)^*)-\Jproj$, \[ E_b\succeq-\eps_{\rm E}I,\qquad \begin{pmatrix}E_b&C_b\\ C_b^*&E_b\end{pmatrix}\succeq-\kappa_{\rm J}I \quad\text{on }L^2(\nu^b)\oplus L^2(\nu^b). \] Let $a_{\rm D}$, $M$, $s$ and $k$ be as in (c), and let $t_Y>0$ satisfy \[ t_Y\le H^{-1},\qquad M\ge H+t_Y,\qquad s\ge s_{\rm J},\qquad kM\ge s^2, \] where \[ s_{\rm J}=M\eps_{\rm E}+H(\kappa_{\rm J}-\eps_{\rm E})_++H\eps_{\rm T} +\Bigl(H+\frac{H^2}{t_Y}\Bigr)\upsilon^2 . \] Then the conclusions of (c) hold. For graded weights, with $h=\eps_{\rm E}/r$, $k_{\rm J}=\kappa_{\rm J}/r$ and \[ f_{\rm J}=\frac{H\{(k_{\rm J}-h)_+r+\eps_{\rm T}\}+(H+H^2/t_Y)\upsilon^2}{r}, \] the conditions read $w_{\rm D}\ge d\,w_{\rm L}$, $w_{\rm S}\ge(H+t_Y)w_{\rm D}$, $w_{\rm R}\ge f_{\rm J}w_{\rm D}+hw_{\rm S}$ and $w_{\rm C}w_{\rm S}\ge w_{\rm R}^2$, together with $t_Y\le H^{-1}$. \end{enumerate} \end{lemma} \begin{proof} (a) By \cref{lem:record:fold-identification}(e), precomposition with $\alpha\in\mathcal G_6$ permutes the fold patterns, maps $E_s$ to $\psi\circ E_s$, permutes the merges of each partition and fixes the constant maps. The law of $\Psi\circ\alpha$ under $\Pi_\phi(\lambda)$ is $\Pi_{\phi\circ\alpha}(\lambda)$, and $\Pi_{\psi\circ E_s}(\pi_{\rm E})= \Pi_{E_s}(\pi_{\rm E})$ because $\pi_{\rm E}$ is exchangeable. Hence every sum $\pi_t$ with $t\ne{\rm L}$ is invariant, and $\Pi_{\rm L}$ is invariant by (v). The cut forms are read off \cref{tab:corner}. The halves of $\Pi_{F_0}$ coincide. For $F_1$ the halves are $(\omega_1,\omega_0,\omega_0)$ and $(\omega_2,\omega_2,\omega_1)$, so its form is $\E_{\pi_{\rm F}}[U_{\omega_1}(\omega_0)V_{\omega_1}(\omega_2)]=\E_b\ip{U_b}{T_{\rm F}^bV_b}$ by (iv); $F_2$ exchanges the two halves and gives the same value. For $E_1$ the form is $\E_{\pi_{\rm E}}[V_{\omega_1}(\omega_0)V_{\omega_1}(\omega_2)]= \E_b\ip{V_b}{T_{\rm E}^bV_b}$ by (iii). For $E_0$ the object on both halves is $\omega_0$, and the form is $\E_{\pi_{\rm E}}[U_{\omega_0}(\omega_1)U_{\omega_0}(\omega_2)] =\E_b\ip{U_b}{T_{\rm E}^bU_b}$, because $(\omega_1,\omega_0,\omega_2)$ again has the law $\pi_{\rm E}$. For the merges $(\omega_0,\omega_1)\sim\Gamma$: $G_e$ gives $\E_\Gamma[U_{\omega_1}(\omega_0)^2]=\E_b\|U_b\|^2$ by (ii), and $G_{01}$, $G_{02}$ give $\E_\Gamma[z_{\omega_0}U_{\omega_0}(\omega_1)]=\E_b[z_bu_b]$ by (ii) and the symmetry of $\Gamma$; $G_o$, $G_{10}$ and $G_{12}$ are the same with $V$ in place of $U$. The constants give $\E_\nu z_b^2$. Finally $\ip\Phi{T\Psi}=\ip\Phi{\Jproj\Psi}+\ip\Phi{(T-\Jproj)\Psi}$ and $\ip\Phi{\Jproj\Psi}=\E\Phi\,\E\Psi$. (b) Fix $b\in\supp\nu$ and omit it from the notation. Let $\Phi_b$ be the sum of the terms of the integrand of $Q_{\mathcal Q_a-a_{\rm L}\Pi_{\rm L}-a_{\rm D}\Pi_{F_0}}(g)$ given by (a): \[ \Phi_b=2a_{\rm D}\ip U{T_{\rm F}V}+a_{\rm S}\bigl(\ip U{T_{\rm E}U}+\ip V{T_{\rm E}V}\bigr) +a_{\rm R}\bigl(\|U\|^2+\|V\|^2+2z(u+v)\bigr)+2a_{\rm C}z^2 . \] By (a) and $2\|U\|\|V\|\le\|U\|^2+\|V\|^2$, \[ \Phi_b\ge(a_{\rm R}-e_{\rm F}a_{\rm D}-e_{\rm E}a_{\rm S})\bigl(\|U\|^2+\|V\|^2\bigr) +a_{\rm S}(u^2+v^2)+2a_{\rm D}uv+2a_{\rm R}z(u+v)+2a_{\rm C}z^2 . \] The first term is nonnegative. With $w=u+v$, $a_{\rm S}(u^2+v^2)+2a_{\rm D}uv=\frac12(a_{\rm S}+a_{\rm D})w^2 +\frac12(a_{\rm S}-a_{\rm D})(u-v)^2\ge\frac12a_{\rm S}w^2$, because $a_{\rm S}\ge a_{\rm D}\ge0$. The binary form $\frac12a_{\rm S}w^2+2a_{\rm R}zw+2a_{\rm C}z^2$ has nonnegative diagonal coefficients and determinant $a_{\rm S}a_{\rm C}-a_{\rm R}^2\ge0$, so $\Phi_b\ge0$. The cut form at $\vartheta_0$ of $\mathcal Q_a-a_{\rm L}\Pi_{\rm L}-a_{\rm D}\Pi_{F_0}$ at $g$ is $\E_b\Phi_b\ge0$, and its cut matrix is symmetric, because $\mathcal Q_a$ and $\Pi_{\rm L}$ are $\vartheta_0$-invariant by (a) and $\Pi_{F_0}$ is fixed samplewise by $\vartheta_0$ (\cref{lem:record:fold-identification}(b)). This is the first claim. Under the root envelope and $a_{\rm D}\ge\delta a_{\rm L}$ (for $a_{\rm L}=0$ the term $a_{\rm L}\Pi_{\rm L}$ vanishes, and the chain holds with $\delta=0$), \[ \mathcal Q_a\succeq_{\vartheta_0}a_{\rm L}\Pi_{\rm L}+a_{\rm D}\Pi_{F_0} \succeq_{\vartheta_0}(a_{\rm D}-\delta a_{\rm L})\Pi_{F_0}\succeq_{\vartheta_0}0, \] the last step by \cref{lem:commoncut}(i). Since $\mathcal Q_a$ is $\mathcal G_6$-invariant, chamber transport (\cref{lem:slot-array}(i)) gives every cut $\vartheta_i$. For the graded weights, divide $a_{\rm D}\ge\delta a_{\rm L}$ and the first displayed condition by $r$ and the second by $r^2$; in the third both sides carry $r^4$, since $3+1=2+2$. (c) Fix $b$ and omit it. Write $U=u+U^\circ$, $V=v+V^\circ$ with $U^\circ,V^\circ\perp\one$, $\sigma_U=\|U^\circ\|$, $\sigma_V=\|V^\circ\|$, and $K=K_b$; only $m_b$ keeps its index. Then $\ip U{KV}=m_buv+u\ip{(I-\Jproj)K^*\one}{V^\circ}+v\ip{U^\circ}{(I-\Jproj)K\one} +\ip{U^\circ}{(I-\Jproj)K(I-\Jproj)V^\circ}$, so the fold data give \[ 2\ip U{KV}\ge2m_buv-2\beta\bigl(|u|\sigma_V+|v|\sigma_U\bigr) -q_\perp(\sigma_U^2+\sigma_V^2). \] Since $T_{\rm E}$ has exact marginals, $\ip U{T_{\rm E}U}=u^2+\ip{U^\circ}{(T_{\rm E}-\Jproj)U^\circ}\ge u^2-\rho_{\rm E}\sigma_U^2$, and likewise for $V$; and $\|U\|^2=u^2+\sigma_U^2$. Hence $\Phi_b/a_{\rm D}$, with $\Phi_b$ as in (b), is at least \[ (s-q_\perp-M\rho_{\rm E})(\sigma_U^2+\sigma_V^2)+(M+s)(u^2+v^2)+2m_buv -2\beta\bigl(|u|\sigma_V+|v|\sigma_U\bigr)+2sz(u+v)+2kz^2 . \] By $2\beta|u|\sigma_V\le t_Yu^2+\beta^2\sigma_V^2/t_Y$ and the same for $(v,\sigma_U)$, this is at least \[ \Bigl(s-q_\perp-M\rho_{\rm E}-\frac{\beta^2}{t_Y}\Bigr)(\sigma_U^2+\sigma_V^2) +A(u^2+v^2)+2m_buv+2sz(u+v)+2kz^2,\qquad A=M+s-t_Y. \] The fluctuation term is nonnegative. With $w_\pm=(u\pm v)/\sqrt2$ the rest is $(A-m_b)w_-^2+(A+m_b)w_+^2+2\sqrt2\,szw_++2kz^2$. Here $A-m_b\ge M-t_Y-H+s\ge s\ge0$, and $A+m_b\ge M+s-t_Y+H^{-1}\ge M$, so the binary form in $(w_+,z)$ has nonnegative diagonal coefficients and determinant $2k(A+m_b)-2s^2\ge2(kM-s^2)\ge0$. Thus $\Phi_b\ge0$, and the rest of the proof is that of (b). For $t_Y=\frac12$: $M\ge2\ge H+\frac12$ and $\frac12<\frac23\le H^{-1}$. The graded form follows as in (b), since $s=w_{\rm R}r/w_{\rm D}$, $M=w_{\rm S}/w_{\rm D}$ and $k=w_{\rm C}r^2/w_{\rm D}$. (d) Fix $c=0$; the coordinate $1$ is the same with the coordinates exchanged. Fix a type $t'$ of the coordinate $1$ and $\phi_1\in P_{t'}$, and let $\mathcal Q^{\rm row}$ be the five-type measure of the row data of $0$ at $\mathfrak f(t')$ with the weights $a_{(t_0,t')}$. For a type $t_0$ and $\phi_0\in P_{t_0}$, the configuration $\Psi_{u_0}=y_{\phi_0(u_0),\cdot,\cdot}$ of rows of $y\sim\lambda_{\mathfrak f(t_0)\mathfrak f(t')}$ has the law of the component $\phi_0$ of the row data: the rows of $\lambda_{{\rm L}\mathfrak f(t')}$ are $\pi_{\rm L}$, the three rows of $\lambda_{{\rm F}\mathfrak f(t')}$ are $\pi_{\rm F}$, those of $\lambda_{{\rm E}\mathfrak f(t')}$ are $\pi_{\rm E}$, and a merge or a constant reads only the rows $0,1$ or the row $0$, whose laws are $\Gamma$ and $\nu$. Moreover $e_{\phi_1}(\Psi)_{(u_0,u_1,\ell)}=y_{\phi_0(u_0),\phi_1(u_1),\ell}$. So the sum of $a_t\Pi_{t,\phi}$ over the states $t=(t_0,t')$ and the patterns $(\phi_0,\phi_1)$ is $(e_{\phi_1})_*\mathcal Q^{\rm row}$, which is the slice decomposition. Let $\vartheta=\vartheta_{0,i}$, with plus half $W_+=H_i\times\Z/6\Z\times\Lambda$. The emission is half-local for the cuts $\vartheta_i$ of $\Z/6\Z$ and $\vartheta$ of $W$ in the sense of \cref{lem:commoncut}(v): $e_{\phi_1}(\Psi)|_{W_+}=\varphi(\Psi|_{H_i})$ and the reflected half of $e_{\phi_1}(\Psi)$ is $\varphi$ of the reflected half of $\Psi$, with $\varphi(x)=(x_{u_0}(\phi_1(u_1),\ell))_{(u_0,u_1,\ell)\in W_+}$ for $x\in\mathfrak X^{H_i}$; so the image of a measure reflection positive at $\vartheta_i$ is reflection positive at $\vartheta$. By (b), (c) or (f), $\mathcal Q^{\rm row}$ is reflection positive at every $\vartheta_i$, and so is each image. Summing over $t'$ and $\phi_1$ proves the claim. (e) A component $\Pi$ of $t$, with the weight $w_tr^{\deg t}$, together with its one-layer diagonal, with the weight $v_tr^{\deg t+1}$, satisfies \[ w_tr^{\deg t}\Pi+v_tr^{\deg t+1}\operatorname{Diag}_\iota(\Pi^{(1)}) \succeq_\iota(v_t-k_tw_t)\,r^{\deg t+1}\operatorname{Diag}_\iota(\Pi^{(1)}) \succeq_\iota0, \] by the hypothesis and because a diagonal copy is fixed samplewise by $\iota$ (\cref{lem:commoncut}(i)); summing over the components gives $\widetilde\mu\succeq_\iota0$. Let $\vartheta$ be a chamber cut, acting on the chamber coordinates only. The diagonal embedding $z'\mapsto z$, $z_{(u,\ell)}=z'_u$, is half-local for $\vartheta$ on the one-layer and on the two-layer slots, so by \cref{lem:commoncut}(v) it preserves the order $\succeq_\vartheta$; this is the statement about $\operatorname{Diag}_\iota$, and the two sums of $\widetilde\mu$ are then reflection positive at the chamber cuts by (b), (c), (d) or (f). Finally $e_\phi$ is half-local for the layer swaps of the field labels and of the slots, so by \cref{lem:commoncut}(v) the image of $\lambda+kr\operatorname{Diag}_\iota(\lambda^{(1)})\succeq_\iota0$ is $(e_\phi)_*\lambda+kr\operatorname{Diag}_\iota((e_\phi)_*\lambda^{(1)})\succeq_\iota0$. The argument uses each component only through its own order at $\iota$ and the one-layer sums only through their own completion inequalities; this is the last sentence of (e). (f) Fix $b$ and omit it; write $U=u+U^\circ$, $V=v+V^\circ$, $\sigma_U$, $\sigma_V$ as in (c), and $\alpha=\ip{U^\circ}{\varphi_0-\one}$, $\alpha'=\ip{\varphi_2-\one}{V^\circ}$, so that $|\alpha|\le\upsilon\sigma_U$ and $|\alpha'|\le\upsilon\sigma_V$. Since $\E\varphi_0=\E\varphi_2=1$ and $C_b$, $R_b$ annihilate the constants on both sides, \[ \ip U{K_bV}=m_b(u+\alpha)(v+\alpha')+m_b\ip{U^\circ}{(C_b+R_b)V^\circ}. \] By $0\le m_b\le H$ and Young's inequality with the allowance $t_Y$, \begin{gather*} 2m_b(u\alpha'+v\alpha)\ge-t_Y(u^2+v^2) -\frac{H^2\upsilon^2}{t_Y}(\sigma_U^2+\sigma_V^2),\\ 2m_b\bigl(\alpha\alpha'+\ip{U^\circ}{R_bV^\circ}\bigr)\ge -H(\upsilon^2+\eps_{\rm T})(\sigma_U^2+\sigma_V^2). \end{gather*} The matching kernel has exact marginals, so $\ip U{T_{\rm E}U}=u^2+\ip{U^\circ}{E_bU^\circ}$, and likewise for $V$. The remaining terms $a_{\rm S}(\ip{U^\circ}{E_bU^\circ}+\ip{V^\circ}{E_bV^\circ}) +2m_ba_{\rm D}\ip{U^\circ}{C_bV^\circ}$ are the form of the block operator $\bigl(\begin{smallmatrix}a_{\rm S}E_b&m_ba_{\rm D}C_b\\ m_ba_{\rm D}C_b^*&a_{\rm S}E_b\end{smallmatrix}\bigr)$ at $(U^\circ,V^\circ)$. Apply \cref{cor:joint-row-split} with $h=\eps_{\rm E}$, $\mathsf k_\Blk=\max(\kappa_{\rm J},\eps_{\rm E})$ and $m=m_b$. Its hypotheses hold because $a_{\rm S}=Ma_{\rm D}\ge Ha_{\rm D}$ and $m_b\le H$; the splitting uses only these block inequalities, not the prime-product origin of the operators. Thus the remaining terms are at least \[ -\bigl(a_{\rm S}\eps_{\rm E}+Ha_{\rm D}(\kappa_{\rm J}-\eps_{\rm E})_+\bigr) (\sigma_U^2+\sigma_V^2). \] Collecting, $\Phi_b/a_{\rm D}$, with $\Phi_b$ as in (b), is at least \[ (s-s_{\rm J})(\sigma_U^2+\sigma_V^2)+A(u^2+v^2)+2m_buv+2sz(u+v)+2kz^2, \qquad A=M+s-t_Y, \] which is the form of the proof of (c) with the fluctuation coefficient $s-s_{\rm J}\ge0$. Its mean part is nonnegative exactly as there, because $M\ge H+t_Y$, $t_Y\le H^{-1}$ and $kM\ge s^2$; so $\Phi_b\ge0$, and the rest of the proof is that of (b). In graded form $\eps_{\rm E}=hr$ and $\kappa_{\rm J}=k_{\rm J}r$, so $s_{\rm J}=(w_{\rm S}/w_{\rm D})hr+f_{\rm J}r$ and $s\ge s_{\rm J}$ reads $w_{\rm R}\ge f_{\rm J}w_{\rm D}+hw_{\rm S}$; the other conditions read as in (c). \end{proof} \begin{corollary}[Joint rows of a block]\label{cor:joint-completion-blocks} Let $\Blk$ be a finite set of primes with least prime $P$, $r=P^{-1/2}$ and $r_p=p^{-1/2}$. Fix a value $b$ of the middle object of a five-type datum whose conditional kernels at $b$ are products over the primes of $\Blk$: $\nu^b=\bigotimes_p\nu_p$, $T^b_{\rm E}=\bigotimes_pT_{{\rm E},p}$ with $T_{{\rm E},p}$ a self-adjoint coupling of $\nu_p$ with itself, and $T^b_{\rm F}=m_bT_{{\rm F},\Blk}$, $T_{{\rm F},\Blk}=\bigotimes_pT_{{\rm F},p}$, with $T_{{\rm F},p}$ of mass one and marginal densities $u_{{\rm L},p}$, $u_{{\rm R},p}$ relative to $\nu_p$. Let $C_{{\rm F},p}=T_{{\rm F},p}-u_{{\rm L},p}\otimes u_{{\rm R},p}$ and $C_{{\rm E},p}=T_{{\rm E},p}-\Jproj_p$, as in \cref{lem:joint-rows}, and suppose that for every $p\in\Blk$ \[ \|C_{{\rm F},p}\|\le c_{\rm F}r_p,\qquad \|C_{{\rm E},p}\|\le c_{\rm E}r_p,\qquad \begin{pmatrix}C_{{\rm E},p}&C_{{\rm F},p}\\ C_{{\rm F},p}^*&C_{{\rm E},p}\end{pmatrix} \succeq-k_{\rm J}r_pI, \] with $c_{\rm F}r,c_{\rm E}r<1$ and $(c_{\rm F}^2+c_{\rm E}^2)r\le k_{\rm J}$. Let $m_b\in[H^{-1},H]$, let the block marginal densities $U_{\rm L}=\bigotimes_pu_{{\rm L},p}$ and $U_{\rm R}=\bigotimes_pu_{{\rm R},p}$ satisfy $\|U_{\rm L}-\one\|,\|U_{\rm R}-\one\|\le\upsilon$, let $E_\Blk=T^b_{\rm E}-\Jproj\succeq-hrI$, and put \[ E_{\rm T}=(2\upsilon+\upsilon^2)\Bigl(\prod_{p\in\Blk}(1+c_{\rm F}r_p)-1\Bigr), \] which is at most $(2\upsilon+\upsilon^2)(e^{nc_{\rm F}r}-1)$ if $\Blk$ has at most $n$ primes. Then the joint data of \cref{lem:five-type}(f) hold at $b$ with $\varphi_0=U_{\rm L}$, $\varphi_2=U_{\rm R}$, $\eps_{\rm E}=hr$, $\kappa_{\rm J}=k_{\rm J}r$ and $\eps_{\rm T}=E_{\rm T}$. Consequently, if this holds at every $b\in\supp\nu$ and $00$; so $\nu'$ has the support of $\nu$ and satisfies every constraint that holds $\nu$-almost surely. \item \emph{(One-way repair.)} If $|u|,|v|\le U<1$, then $\|f\|_2,\|g\|_2\le U/(1-\rho)$ and $\|f\|_\infty,\|g\|_\infty\le F:=U(1+K_\infty/(1-\rho))$; if $2F<1$, (c) applies. \item \emph{(Swap symmetry.)} If $X=Y$, $\nu$ is invariant under $(x,y)\mapsto(y,x)$ and $\mu_X=\mu_Y$, then $A^*=A$ and $f=g=s$, where $s$ is the centred solution of $(I+A)s=u$; $\nu'$ is swap invariant. \item \emph{(Centred norm and difference.)} Under (c) and $U_X,U_Y<1$, $\nu'$ satisfies the hypotheses of \cref{lem:record:additive-cancellation} with the bounds $U_X,U_Y,e_X,e_Y$ above (or any $e_X,e_Y$ with $e_Xe_Y\ge\|u\|_2\|v\|_2$) and any $F_X\ge\|f\|_\infty$, $F_Y\ge\|g\|_\infty$; so its centred conditional operator, relative to $\mu_X,\mu_Y$, has norm at most \[ \rho'=\frac{\rho(1+F_X+F_Y)+e_Xe_Y}{\sqrt{(1-U_X)(1-U_Y)}}; \] in the case of (d), \[ \rho'\le\frac{\rho(1+2F)+U^2}{1-U}\le\frac{\rho(1+2F)+U^2+2FU}{1-U}. \] If $\pi$ is a coupling of $\mu_X$ and $\mu_Y$ whose centred conditional operator has norm at most $\rho(\pi)$, then $\nu'-\pi$ has zero marginals and, as an operator from $L^2(\mu_Y)$ to $L^2(\mu_X)$, norm at most $\rho'+\rho(\pi)$. \item \emph{(Neumann series split after $N$ terms.)} For this part $\rho<1$ is not assumed. Let $\mathcal V_X\subseteq L^2_0(\nu_X)$ and $\mathcal V_Y\subseteq L^2_0(\nu_Y)$ be subspaces with $A\mathcal V_Y\subseteq\mathcal V_X$, $A^*\mathcal V_X\subseteq\mathcal V_Y$ and $\|A|_{\mathcal V_Y}\|\le\rho_I<1$. If $u\in\mathcal V_X$, $v\in\mathcal V_Y$, $|u|,|v|\le U$ and $\|u-Av\|_2,\|v-A^*u\|_2\le e_I$, then \[ f=\sum_{j\ge0}(AA^*)^j(u-Av)\in\mathcal V_X,\qquad g=\sum_{j\ge0}(A^*A)^j(v-A^*u)\in\mathcal V_Y \] solve the equations of (a), and for every integer $N\ge1$ \[ \|f\|_\infty,\ \|g\|_\infty\le F_N:=2NU+\frac{K_\infty\rho_I^{2N-1}e_I}{1-\rho_I^2} . \] If $2F_N<1$, the conclusions of (c) hold for this solution. If a group acts on $X$ and on $Y$, the diagonal action $(x,y)\mapsto(gx,gy)$ preserves $\nu$, and $\mathcal V_X$, $\mathcal V_Y$ consist of invariant functions, then $f$, $g$ and $\nu'$ are invariant. \end{enumerate} \end{lemma} \begin{proof} (a) $A$ maps centred functions to centred functions, since $\E_{\nu_X}Ag=\E_{\nu_Y}g$. The positive operator $AA^*$ on $L^2_0(\nu_X)$ has norm at most $\rho^2<1$, so $I-AA^*$ is invertible, and substitution gives $f+Ag=(I-AA^*)f+Av=u$ and $g+A^*f=v$; the targets are centred because $\mu_X$ and $\mu_Y$ are probability measures. If $(f,g)$ solves the equations with $u=v=0$, then $f=AA^*f$, so $f=0$ and $g=0$: the solution is unique. For centred $f,g$ the marginal densities of $\nu'$ are $1+f+\E_\nu[g(y)\mid x]=1+f+Ag=1+u$ and $1+v$. Taking norms in each equation separately, $\|f\|\le e_X+\rho\|g\|$ and $\|g\|\le e_Y+\rho\|f\|$, so $\|f\|\le e_X+\rho e_Y+\rho^2\|f\|$, which is the first bound; likewise for $g$. (The norm $\rho$ of the off-diagonal operator on $L^2_0(\nu_X)\oplus L^2_0(\nu_Y)$ alone would give only $\|(f,g)\|\le\|(u,v)\|/(1-\rho)$, a loss of $\sqrt2$ in the one-way case.) A symmetry of the data commutes with $A$ and $A^*$ and maps a centred solution to a centred solution, which is therefore the same one. (b) $f=u-Ag$, so $\|f\|_\infty\le\|u\|_\infty+K_\infty\|g\|_2$, and (a) bounds $\|g\|_2$. If $k=d\nu/d(\nu_X\otimes\nu_Y)$, then $|Ag(x)|^2\le\int k(x,y)^2\,\nu_Y(dy)\,\|g\|_2^2\le\sup k\,\|g\|_2^2$, because $\int k(x,y)\,\nu_Y(dy)=1$. (c) By (a) $\nu'$ has mass one and the marginals $\mu_X,\mu_Y$, and $1+f+g\ge1-\|f\|_\infty-\|g\|_\infty>0$ on the support of $\nu$. (d) With $U_X=U_Y=e_X=e_Y=U$, (a) gives $U(1+\rho)/(1-\rho^2)=U/(1-\rho)$ and (b) gives $U+K_\infty U/(1-\rho)=F$. (e) Under the swap the system for $(f,g)$ becomes the system for $(g,f)$; by uniqueness $f=g$, and then $f+Af=u$. (f) $\nu'\ge0$ by (c), $f,g$ are centred and $1+u,1+v$ are the densities of the marginals of $\nu'$, with $u\ge-U_X$ and $v\ge-U_Y$; \cref{lem:record:additive-cancellation} gives $\rho'$, and in the case of (d) $F_X=F_Y=F$, $e_Xe_Y\le U^2$ and $\sqrt{(1-U)^2}=1-U$. Finally $\nu'$ and $\pi$ have the same marginals; their operators relative to $\mu_X,\mu_Y$ agree on the constants, both fix them on both sides, and both map centred functions to centred functions, so the difference is the difference of the centred parts, of norm at most $\rho'+\rho(\pi)$. (g) Since $A^*\mathcal V_X\subseteq\mathcal V_Y$, the restriction of $A^*$ to $\mathcal V_X$ is the adjoint of $A|_{\mathcal V_Y}\colon\mathcal V_Y\to\mathcal V_X$; so $AA^*$ maps $\mathcal V_X$ into itself with norm at most $\rho_I^2$, and $A^*A$ maps $\mathcal V_Y$ into itself with norm at most $\rho_I^2$. Hence both series converge, $f\in\mathcal V_X$, $g\in\mathcal V_Y$, $(I-AA^*)f=u-Av$, and $A^*(AA^*)^j=(A^*A)^jA^*$ gives $g=\sum_j(A^*A)^jv-\sum_j(A^*A)^jA^*u=v-A^*f$. Then $g+A^*f=v$ and $f+Ag=(I-AA^*)f+Av=u$. The operators $A$ and $A^*$ are conditional expectations, hence contractions of $L^\infty$, so each of the first $N$ terms of the series for $f$ has sup norm at most $\|u-Av\|_\infty\le2U$. For $j\ge N$ write $(AA^*)^j(u-Av)=A\bigl[A^*(AA^*)^{j-1}(u-Av)\bigr]$; its sup norm is at most $K_\infty\|A^*(AA^*)^{j-1}(u-Av)\|_2\le K_\infty\rho_I^{2j-1}e_I$. Summing over $j\ge N$ gives $F_N$, and the same argument with $A$ and $A^*$ exchanged bounds $g$. The marginal densities of $\nu'$ are $1+f+Ag=1+u$ and $1+g+A^*f=1+v$, as in (a), and the proof of (c) applies. In the last claim $f\in\mathcal V_X$ and $g\in\mathcal V_Y$ are invariant, and so is $\nu'=(1+f+g)\nu$, since $\nu$ is. \end{proof} \begin{remark}[Blocks and the certified forms]\label{rem:repair-forms} (1) On a block the replaced and the repaired records are tensor products over the primes whose prime operators fix the constants of the same marginal spaces; if every prime centred norm of both is at most $\frac12$, \cref{lem:sector}(b) bounds the block difference by the largest prime difference: on functions with exact support a set $S$ of $k$ primes the difference is a sum of $k$ terms, each the prime difference at one prime of $S$ times centred factors of norm at most $\frac12$ at the other $k-1$ primes, hence at most $k2^{1-k}\le1$ times the largest prime difference, and on the empty support the difference vanishes. (2) The certificates evaluate (f) in two forms. The middle merge repairs (\cref{lem:merge-repair}) use the weaker form with $+2FU$, which the stronger one implies, with the influence bound for $\rho(\pi)$; the one-way repairs of the upper range (\cref{sec:upper-comparison}) use $(\rho(1+2F)+U^2)/(1-U)$, with the smaller of the influence bound and the spectral bound of the replaced record for $\rho(\pi)$, and in their joint-star refinement a smaller bound for $\|u\|_2\|v\|_2$ in place of $U^2$, which (f) allows. In every case the targets are the actual half marginals of the replaced record, the solution of (a) keeps the support of the new graph law, and (a) makes it invariant under the square-affine maps when the data are. (3) The dense comparisons of the upper range and the components of its six-query mixture (\cref{prop:dense-comparison,prop:le-mixture}) are repaired by (g) on the functions invariant under the square-affine maps, where the centred leading stars vanish; on these subspaces $\|A\|\le\rho_I$ with the certified $\rho_I<1$ of the applications, and the tail of the series in (g) beyond its first $N$ terms contributes at most $K_\infty\rho_I^{2N-1}e_I/(1-\rho_I^2)$ to the $L^\infty$ bound $F_N$ there; the certificates record $N$ for each endpoint ($N=2$ for the dense records, $N=1$ for the components of the mixture). The changes of these records, and those of the forest records (\cref{prop:forest-records}), from the records they replace are bounded in the actual marginal space by \cref{lem:record:centered-correction}: for the dense comparisons and the mixture by its part (c), without a marginal-variance term; for the forest records by its part (b), which also gives the full operator norms on $L^2(m)$ entering the block-gate inequalities \eqref{eq:upper-block-gate} for the forest records, and for the field pairs FE and EF the symmetric part by its part (c). \end{remark} A repaired law is compared with the record it replaces in the space of its actual marginals, while its bounds are proved in one common fixed half chart. The next lemma carries out this change of space for a reweighting $(1+f(x)+g(y))K$. It bounds separately the norm of the centred operator and the norms of its symmetric and skew parts; and against a second law with the same marginals, the rank-one terms produced by centring on the left and on the right cancel, so that no marginal-variance term remains. \begin{lemma}[Centred additive correction]\label{lem:record:centered-correction} Let $\nu$ be a probability measure on a finite set $\mathcal H$, $\Pi_\perp=I-\Jproj$ on $L^2(\nu)$, and $K$ a real kernel on $\mathcal H\times\mathcal H$ with $\int K\,d(\nu\otimes\nu)=1$ (in the applications a probability density relative to $\nu\otimes\nu$). Write $h\otimes k$ for the kernel $h(x)k(y)$, and put $\delta_L=K\one-\one$, $\delta_R=K^*\one-\one$ and $K_c=\Pi_\perp K\Pi_\perp$, so that \[ K=\one\otimes\one+\delta_L\otimes\one+\one\otimes\delta_R+K_c , \] with $\delta_L$, $\delta_R$ centred. Let $\|K_c\|\le c$, $\|\operatorname{Sym}K_c\|\le s$, $\|\operatorname{Skew}K_c\|\le a$ and $\|\delta_L\|_\nu,\|\delta_R\|_\nu\le e$, all on $L^2(\nu)$. Let $f$, $g$ be real functions on $\mathcal H$ with $\|f\|_\infty,\|g\|_\infty\le F$, and $K'=(1+f(x)+g(y))K$. Here a kernel $\kappa$ denotes both the measure $\kappa\,d(\nu\otimes\nu)$ and the operator $h\mapsto\int\kappa(\cdot,y)h(y)\,\nu(dy)$ on $L^2(\nu)$; its half marginals are the marginals of that measure. For a kernel $\kappa$ of mass one with both half marginals equal to a probability measure $m$, the \emph{centred operator} $\mathcal C_\kappa$ on $L^2(m)$ is defined by $\ip\phi{\mathcal C_\kappa\psi}_m=\int\phi(x)\psi(y)\kappa(x,y)\,\nu(dx)\,\nu(dy) -\E_m\phi\,\E_m\psi$; for a probability density it is the centred conditional operator relative to the marginals. \begin{enumerate}[label=\textup{(\alph*)}] \item The centred correction $D=\Pi_\perp(K'-K)\Pi_\perp$ is \[ D=(\Pi_\perp f)\otimes\delta_R+\delta_L\otimes(\Pi_\perp g) +\Pi_\perp(fK_c)\Pi_\perp+\Pi_\perp(K_cg)\Pi_\perp , \] where $fK_c$ and $K_cg$ are the kernels $f(x)K_c(x,y)$ and $K_c(x,y)g(y)$, and \[ \|D\|\le\|f\|_\nu\|\delta_R\|_\nu+\|\delta_L\|_\nu\|g\|_\nu +(\|f\|_\infty+\|g\|_\infty)\|K_c\|\le2F(c+e). \] \item Suppose that $K'$ has mass one and both half marginals $m=(1+u_0)\nu$, with $1+u_0\ge e^{-\ell_m}$ and $\|u_0\|_\nu^2\le b_0$. Then \[ K'-(1+u_0)\otimes(1+u_0)=K_c+D-u_0\otimes u_0 , \] and the norms of $\mathcal C_{K'}$, of its symmetric part and of its skew part are at most \[ e^{\ell_m}\bigl(c+2F(c+e)+b_0\bigr),\qquad e^{\ell_m}\bigl(s+2F(c+e)+b_0\bigr),\qquad e^{\ell_m}\bigl(a+2F(c+e)\bigr). \] \item Suppose moreover that $O$ is a kernel of mass one with the same half marginals $m$ (in the applications the record that is replaced). Then \[ K'-O=\Pi_\perp(K-O)\Pi_\perp+D , \] and the symmetric and skew parts of $\mathcal C_{K'}-\mathcal C_O$ have norms at most $e^{\ell_m}(\|\operatorname{Sym}\Pi_\perp(K-O)\Pi_\perp\|+2F(c+e))$ and $e^{\ell_m}(\|\operatorname{Skew}\Pi_\perp(K-O)\Pi_\perp\|+2F(c+e))$: there is no marginal-variance term. \end{enumerate} \end{lemma} \begin{proof} The kernel $h(x)k(y)$ has the compression $(\Pi_\perp h)(x)(\Pi_\perp k)(y)$, so a term that is constant in $x$ or in $y$ is killed by $\Pi_\perp\cdot\Pi_\perp$. The four terms of the decomposition of $K$ are its four compressions by $\Jproj$ and $\Pi_\perp$: $\Jproj K\Jproj=\one\otimes\one$ because $K$ has mass one, $\Pi_\perp K\Jproj=(K\one-\one)\otimes\one$, $\Jproj K\Pi_\perp=\one\otimes(K^*\one-\one)$, and $\delta_L$, $\delta_R$ are centred for the same reason. (a) Expand $(f(x)+g(y))K$ with this decomposition and compress. In $f(x)K(x,y)$ the terms $f\otimes\one$ and $(f\delta_L)\otimes\one$ are killed, and $f\otimes\delta_R$ and $fK_c$ give $(\Pi_\perp f)\otimes\delta_R$ and $\Pi_\perp(fK_c)\Pi_\perp$, since $\Pi_\perp\delta_R=\delta_R$; in $g(y)K(x,y)$ the terms $\one\otimes g$ and $\one\otimes(g\delta_R)$ are killed, and $\delta_L\otimes g$ and $K_cg$ give the other two terms. The rank-one terms have norms $\|\Pi_\perp f\|_\nu\|\delta_R\|_\nu\le\|f\|_\nu\|\delta_R\|_\nu$ and $\|\delta_L\|_\nu\|\Pi_\perp g\|_\nu\le\|\delta_L\|_\nu\|g\|_\nu$; the last two are compressions of the products of $K_c$ with the multiplications by $f$ and by $g$, of norms at most $\|f\|_\infty\|K_c\|$ and $\|g\|_\infty\|K_c\|$. With $\|f\|_\nu\le\|f\|_\infty\le F$ and $\|g\|_\nu\le F$ this is at most $2F(c+e)$. The bound uses only the sup norms of $f$, $g$, and no centring of them. (b) Since $K'\one=K'^*\one=1+u_0$ and $\E_\nu u_0=0$, the kernel $X=K'-(1+u_0)\otimes(1+u_0)$ annihilates the constants on both sides, so it equals its compression $\Pi_\perp K'\Pi_\perp-u_0\otimes u_0=K_c+D-u_0\otimes u_0$. By the density transport of \cref{lem:record:actual-correlation}(b), with $\psi=1+u_0$ and $W\phi=(1+u_0)^{1/2}\phi$, \[ \mathcal C_{K'}=W^*M_{1+u_0}^{-1/2}XM_{1+u_0}^{-1/2}W. \] Here $M_{1+u_0}$ denotes multiplication by $1+u_0$. The transport multiplies norm bounds by at most $e^{\ell_m}$ and preserves symmetric and skew parts. The rank-one term $u_0\otimes u_0$ is self-adjoint, of norm $\|u_0\|_\nu^2\le b_0$, so it enters the full and the symmetric norms and not the skew one; and the symmetric and skew parts of $D$ have norms at most $\|D\|$. (c) $K'$ and $O$ have mass one and the same half marginals, so $K'-O$ annihilates the constants on both sides and equals its compression $\Pi_\perp(K'-O)\Pi_\perp=\Pi_\perp(K-O)\Pi_\perp+D$. As in (b), $\mathcal C_{K'}-\mathcal C_O=W^*M_{1+u_0}^{-1/2}(K'-O)M_{1+u_0}^{-1/2}W$: the two subtractions $(1+u_0)\otimes(1+u_0)$ cancel. Take symmetric and skew parts. \end{proof} A second way to correct the marginals of a positive kernel adds instead of reweighting. If a coupling $J$ with the prescribed (target) marginals and the required support is at hand, a kernel with marginal defects $\alpha,\beta$ bounded in absolute value by $M$ and satisfying $J\beta=0$ and $J^*\alpha=0$ is corrected by the added term $J(\alpha+\beta+2M)$ of \cref{cor:markov-completion}. This uses neither the inversion of $I-AA^*$ nor a hypothesis $\rho<1$, and the centred change is at most $2M(\|QRQ\|+2\|QJQ\|)$ there. \begin{corollary}[Completion by mixing in a coupling of the target marginals]\label{cor:markov-completion} Let $m_X$, $m_Y$ be probability measures on finite sets $X$, $Y$, and let $R\ge0$ be a density relative to $m_X\otimes m_Y$ of mass one, with marginal defects $\alpha=\one-R\one$ and $\beta=\one-R^*\one$, $|\alpha|,|\beta|\le M$. Let $J\ge0$ be a density relative to $m_X\otimes m_Y$ with $J\one=\one$ and $J^*\one=\one$ (a coupling of $m_X$ and $m_Y$) such that $J\beta=0$ and $J^*\alpha=0$. Then \[ P=\frac{R+J\bigl(\alpha(x)+\beta(y)\bigr)+2MJ}{1+2M}, \] where $J(\alpha(x)+\beta(y))$ is the kernel $J(x,y)(\alpha(x)+\beta(y))$, is a probability density relative to $m_X\otimes m_Y$ with marginals $m_X$ and $m_Y$, it vanishes wherever $R$ and $J$ both vanish, and, with $Q$ the projections off the constants, \[ \|Q(P-R)Q\|\le2M\bigl(\|QRQ\|+2\|QJQ\|\bigr), \] the norms being those of operators from $L^2(m_Y)$ to $L^2(m_X)$. If a group acts on $X$ and on $Y$ preserving $m_X$ and $m_Y$, and the diagonal action on $X\times Y$ preserves the densities $R$ and $J$, then $P$ is invariant under the diagonal action. \end{corollary} \begin{proof} $J(x,y)(\alpha(x)+\beta(y)+2M)\ge0$ because $\alpha+\beta\ge-2M$, so $P\ge0$. As an operator the kernel $J(x,y)(\alpha(x)+\beta(y))$ is $M_\alpha J+JM_\beta$, with $M_\alpha$ the multiplication by $\alpha$. By $J\one=\one$ and $J\beta=0$, $(1+2M)P\one=(\one-\alpha)+\alpha+0+2M\one$; by $J^*\one=\one$ and $J^*\alpha=0$, $(1+2M)P^*\one=(\one-\beta)+0+\beta+2M\one$. So $P$ has the marginals $m_X$ and $m_Y$, and mass one; the support claim is clear. Next, $J$ maps centred functions to centred functions, since $\ip\one{J\psi}=\ip{J^*\one}\psi$, and constants to constants; so $JQ=QJQ$ and $QJ\Jproj=0$. Hence $QM_\alpha JQ=QM_\alpha(QJQ)$ and $QJM_\beta Q=(QJQ)(QM_\beta Q)$, and $\|Q(M_\alpha J+JM_\beta)Q\|\le2M\|QJQ\|$. Therefore \[ Q(P-R)Q=\frac{Q(M_\alpha J+JM_\beta)Q+2M\,QJQ-2M\,QRQ}{1+2M} \] has norm at most $2M(\|QRQ\|+2\|QJQ\|)$. Finally $\alpha$ and $\beta$ are invariant when $R$, $m_X$ and $m_Y$ are, and the formula for $P$ is equivariant. \end{proof} \paragraph{Consequences and what to read next.} From \cref{sec:positivity}: cut matrices and the order $\succeq_\vartheta$ (\cref{def:cc:order}, \eqref{eq:cc:kron}, \cref{rem:cut-symmetries}), diagonal laws of samplewise fixed records and images under half-local maps (\cref{lem:commoncut}(i),(v)), block brackets and their tensorization (\cref{lem:record:block-gram}, with (d) for symmetric brackets), and the chamber group with chamber transport (\cref{def:slot-array,lem:slot-array}). From \cref{sec:lifts}: the sector lemma (\cref{lem:sector}), for block differences. From \cref{sec:labellings}: the laws $\lambda_{\Blk}(G)$ (\cref{def:graphs:labeling}). From \cref{sec:cuts}: the recentering identity (\cref{lem:recentering}(a)) and density transport (\cref{lem:record:actual-correlation}(b)). From \cref{sec:extraction}: the joint fold and matching rows (\cref{lem:joint-rows}(b),(c), \cref{cor:joint-row-split}). Nothing from Part~III or Part~V is used; the references to Part~V name applications. \space % End sections/17_completion_repair % Begin sections/18_design \section{Overview of the construction verifying (CP0)--(CP8)}\label{sec:design} \paragraph{What this section proves and how to read it.} Part~V exhibits laws satisfying (CP0)--(CP8) with baseline $\Theta<\PushTheta<1$. This section specifies the construction once: parameters, queries, prime ranges, and which graph law is used in each range. Later sections verify the hypotheses range by range; each ends by naming the rows of \cref{tab:hypotheses} it proves. Inputs: Theorem~C and Part~IV. Output: the standing data \cref{def:record:parameters} for the baseline. The improved ($\vartheta>1$) parameters differ and are specified in \crefrange{sec:density:moments-prefix}{sec:four-routes-closing}; do not use baseline numbers there. ``Admissible'' in Part~V has three qualified senses, distinguished in \cref{subsec:design-admissibility}: admissible for the energy estimates (\cref{def:admissible}), admissible tuples (local degree conditions), and admissible price bounds $c_{\mathcal C}$ (allowed (CP5) scalars). Where a sum is computed at a smaller evaluation exponent and converted to $a$ (repricing), \cref{lem:record:repricing,cor:first-stage-repricing} justify the step and require $a\ge a_0$. The prime ranges are: prefix $p\equiv1\pmod4$, $p<2^{512}$ (\cref{sec:frontier:iidprefix}); middle $p\equiv3\pmod4$ in $[Q_3,P_3)$ (\crefrange{sec:middle-reference}{sec:matching-mean}); upper $p\equiv3\pmod4$ in $[P_3,2^{512})$ (\cref{sec:upper-reference,sec:upper-comparison}); large primes $p\ge2^{512}$ and the external index (\cref{sec:tail-index}); closing (\cref{sec:closing}). Baseline totals are $L_0,S,A,D,\mathcal E,T,R_I,J,W,m$ as in \cref{subsec:intro:inequality,tab:intro:values}. \subsection{The baseline numerical parameters}\label{subsec:design-parameters} The construction is now fixed completely: exponents, number of intervals, prime ranges, and which law is used in each range. These are the baseline values ($\theta=\vartheta=1$); the improved closing changes only the values named in \cref{sec:four-routes-closing}. \begin{definition}[Parameters]\label{def:record:parameters} The construction has the following data. \begin{enumerate}[label=(\alph*)] \item \emph{Exponents.} The price exponent $a=\PushA$, the density exponent $\theta=1$, and the exponent of the baseline theorem $\eps=a/(72-\theta)=a/71=\PushExponent$. \item \emph{Slots, queries and intervals.} The slot array $V=(\Zsix)^2\times\{0,1\}$ with its family $\mathfrak F$ of cuts and its reserved cut $\iota$ (\cref{def:slot-array}); the six queries $\mathcal E_6$ (\cref{subsec:front6:construction}); and $\Kint=\PushK$ intervals. \item \emph{Prime ranges.} \begin{itemize} \item \emph{Prefix:} the primes $p\equiv1\pmod4$ below $\Pfour=2^{512}$. Each is an atom $\{p\}$ with label group $\Z/p^{e_p}\Z$, $e_p=2\mcl$, $\mcl=8192$ digit pairs, carrying the square-clique law of \cref{def:clique-law}. \item \emph{Small modulus:} $\Mzero=2^{2m_{\rm ext}+1}\prod_{3\le p0$ (\cref{cert:record:frame-data}(a)); the strict inequalities (S1)--(S7) of the analytic stage hold (\cref{cert:record:analytic-stage}), and the gates of the analytic transfer that depend on $a$ hold on the whole interval $0{\raggedright\arraybackslash}p{2.55cm}% >{\raggedright\arraybackslash}p{4.55cm}% >{\raggedright\arraybackslash}p{3.3cm}% >{\raggedright\arraybackslash}p{4.25cm}@{}} \caption{The ranges of primes.}\label{tab:ranges}\\ \toprule Range & Reference law and its positivity & Comparison change & Contribution to $\Theta$\\ \midrule \endfirsthead \toprule Range & Reference law and its positivity & Comparison change & Contribution to $\Theta$\\ \midrule \endhead \bottomrule \endfoot Small modulus: $2^{129}$ and $p^{128}$ for $3\le p{\raggedright\arraybackslash}p{3.45cm}% >{\raggedright\arraybackslash}p{4.4cm}% >{\raggedright\arraybackslash}p{3.65cm}% >{\raggedright\arraybackslash}p{3.15cm}@{}} \caption{The laws of the construction and their admissibility.}\label{tab:admissibility}\\ \toprule Law & Sign; one-slot marginals (O1) & Sharp bounds (O2) & Proved in\\ \midrule \endfirsthead \toprule Law & Sign; one-slot marginals (O1) & Sharp bounds (O2) & Proved in\\ \midrule \endhead \bottomrule \endfoot prefix: $\lambda_p$, the exception $\lambda^{\rm ex}_p$, $\lambda_p-\lambda^{\rm ex}_p$ & nonnegative; invariant under $\mathfrak G_p$ & none; the exception is charged by its mass & \cref{lem:frontier:iidlocal}(vi)\\ middle and upper references $\mu_{\Blk}$ & nonnegative; invariant under the maps of \ref{it:record:R3} & none & \cref{lem:front12:reference}, \cref{lem:positive-root-properties,lem:imp:coherent39-law}, \cref{lem:upper-reference-rp}\\ first-stage and bracket records $F_{\rm fold}$, $E_{\rm fold}$, $E_{\rm add}$, $G$, $H$; $\Nbrz-\mu=E_{\rm add}+G+H$ & nonnegative, reserved diagonal; images of invariant laws under vertex maps, then diagonal copies & none; variation and mass prices & \cref{def:record:frame}, \cref{lem:record:gram}\\ one-stage repair $E_{\rm new}$ & nonnegative, reserved diagonal; invariant & $k_{\rm new}(X)b^{-1/2}$, and $s_{\rm fold}(X)/b$ for the symmetric part, for every value of the shared label, where $X$ is the piece start and $b$ the least prime of the block & \cref{lem:record:one-stage-folded-e}\\ middle comparison records: the three product components of each signed fold record, the law $K_1$, merge and two-layer constant repairs & nonnegative; invariant under the maps of \ref{it:record:R3}, independently at the primes of the block; the actual half marginals of the replaced record & operator norms between actual half spaces at $\iota$, nothing conditioned & \cref{lem:signed-components}, \cref{prop:signed-bounds}, \cref{lem:record:exact-marginal-e}, \cref{lem:merge-repair,lem:record:accepting-c2}; \cref{lem:middle-comparison-prices}\\ upper and tail comparison laws: one-way repairs, the dense EL comparison, the components of the LE mixture & nonnegative; the actual half marginals of the replaced record, each mixture component repaired to them before mixing & as for the middle records & \cref{prop:record:upper}, \cref{prop:dense-comparison}, \cref{prop:le-mixture}, \cref{lem:tail-prices}\\ deleted records (middle, upper, tail) & records of the reference & none; charged by mass (\cref{rem:cp:charging}) & \cref{lem:middle-comparison-prices}, \cref{prop:record:upper}, \cref{lem:tail-prices}\\ tail law $\mu_p$, $p\ge\Pfour$ & as the upper references, at one prime & none & \cref{lem:tail-law}\\ selected laws of the variance credits & positive; invariant under independent translations at the primes of their blocks & $d=1$ for a probability coupling; centred norms of a record's own operator at $\iota$ & \cref{def:record:eligible}, \cref{lem:var-gain}\\ couplings of the positive joint envelopes & normalized positive couplings, among them the singleton couplings $M_{ij}=V_iV_j^*$ (a uniform label and independent conditioned halves); invariant under translations at each prime & none (the envelope bounds are brackets at $\iota$ between actual half spaces) & \cref{thm:envelopes}(iv), \cref{lem:oct24:mask-schur}\\ matching-envelope diagonals $M_{s,\Blk}-\Nbr_{\Blk}$ & positive, reserved diagonal (norm envelopes and chosen side diagonals); normalizations with uniform one-slot marginals & block Grams at $\iota$ between actual half spaces & \cref{prop:record:matching}, \cref{prop:signed-sides}\\ companions of the mean credit & positive normalized laws fixed by $\iota$, uniform one-slot marginals & none & \cref{lem:record:companion-energy}\\ \end{longtable} } \paragraph{How the table is read.} For (O1), every law of the table is nonnegative (a signed fold record of the middle enters only through its three nonnegative product components, each of which is such a law), and its one-slot marginals are uniform for one of two reasons named in the table: it is invariant under the translations, or all square-affine maps, at the primes of its atom, so that \cref{lem:marginals}\ref{it:marg:one} applies; or it is nonnegative with the actual half marginals of such an invariant law, whose one-slot marginals it therefore shares. Invariance passes to every law that the reductions of Part~III produce from these: to variations, normalizations, restrictions to invariant events, half marginals and their diagonal copies, images under folds and pullbacks, products over disjoint atoms and mixtures (\cref{lem:marginals}\ref{it:marg:closure}). Every law of the table is a law of the field labels of its atoms, and the index is external (\cref{def:cp0}(d)); so no law depends on the interval index $b_e$, the residue $s_e$, or the inclusion indices of \cref{def:hyb:coupled}, which is the last clause of (O1). For (O2), the third column says why every sharp bound applied to the law holds uniformly in the shared labels: either it is an operator norm between actual half spaces with nothing conditioned, or it is proved for every value of the shared label. The remaining two obligations concern the reductions, not the laws. (O3): the index-support projections are taken before the field folds and the inclusion conductors are averaged last, in the reductions of Part~III (\cref{lem:record:common-mean,lem:record:wrap-expansion,lem:envelope-energy}), and no section of Part~V changes this order. (O4): every chamber fold commutes with $\iota$ on the slot array (\cref{lem:slot-array}(iii)). \subsection{Where the hypotheses are verified (guide to Part~V)}\label{subsec:design-table} \Cref{tab:hypotheses} lists each hypothesis of \cref{thm:comparison}, what Part~V shows for the construction of \cref{def:construction}, and the statements that show it. The frame data (CP0) are verified by the parameters above, by the slot array (\cref{lem:slot-array}) and by the index law (\cref{prop:oct24-index-cost,lem:index-moments}); the hypotheses (CP1)--(CP7) range by range in the following sections; the admissibility clause (CP8)(a) by \cref{tab:admissibility}; and the summability clause (CP8)(c) because only the tail atoms are infinitely many and their prices are summable (\cref{lem:tail-prices}(iv)), while the auxiliary prices of (CP5) are nonzero only at the finitely many middle atoms. The robustness clause (CP8)(b) follows from \cref{lem:record:rec}(i) (\cref{rem:cp:robust-final}): under the inflation of \cref{def:robust} (multiplying structured energy bounds by $1+z$ and adding remainders at most $zY$), every certified inequality (gate) whose left side changes is strict, except two: the orbit saving of \cref{lem:orbit-coupon}, which is a nonnegativity condition on a coefficient that only grows under inflation, and the hypothesis $\chi<1$ selecting the branch of the restoration function \eqref{eq:density:restoration}, which inflation preserves. The remaining non-strict gates concern fixed numbers of the construction. Only the finitely many middle blocks carry signed comparison laws (\cref{def:construction}(d)), so the variation factor of \cref{def:cp4} is finite and independent of the scale. \paragraph{Consequences and what to read next.} This section uses the slot array and its queries (\cref{def:slot-array}, \cref{lem:slot-array}(iii), (iv), (v)); the comparison data and the hypotheses (CP0)--(CP8) (\cref{def:cp0,def:cp1,def:cp2,def:cp3,def:cp4,def:cp5,def:cp6,def:cp7,def:cp8}); admissibility and its closure under the operations of the reductions (\cref{def:admissible}, \cref{lem:marginals}); the functional, the analytic stage and the repricing (\cref{def:record:functional}, \cref{def:record:analytic-stage}, \cref{cert:record:analytic-stage}, \cref{lem:record:repricing}, \cref{cor:first-stage-repricing}); and, as pointers, the construction lemmas named in \cref{tab:ranges,tab:admissibility}. \paragraph{Hypotheses verified in this section (\cref{tab:hypotheses}).} (CP0)(b) for the construction: the atoms and exponents of \cref{def:record:parameters}, with $a<\sigma$, the stage inequalities (S1)--(S7) and the analytic gates on $00$; for the twelve queries of \cref{subsec:front12:construction}, $\lambda^{\rm ex}_p(1)=\eta_{\mcl}=2^{1-\mcl}-2^{-2\mcl}$. In both cases $\lambda^{\rm ex}_p(1)\le\eta_{\mcl}$. \item The measures $\lambda_p$, $\lambda^{\rm ex}_p$ and $\lambda_p-\lambda^{\rm ex}_p$ are admissible (\cref{def:admissible}). Thus $\mu_p=\lambda_p$ satisfies \ref{it:record:R1}--\ref{it:record:R3} of \cref{hyp:record:reference}, with \ref{it:record:R2} at every cut of $\mathfrak F$, and the accepted part of $\lambda_p-\lambda^{\rm ex}_p$ for $\mathcal Q=\mathcal E_6$ satisfies \ref{it:record:R5}. \end{enumerate} \end{lemma} \begin{proof} \emph{The clique.} Since $A_j\equiv a_j$ and $B_j\equiv b_j\pmod p$ and $b_j-a_j$ is a nonzero square in $\Fp$ by the definition of $\Om$, $A_j\ne B_j$. Let $x=\sum_jp^{2j}x_j$ and $x'=\sum_jp^{2j}x'_j$ be given by two different choices, and let $j$ be the least index with $x_j\ne x'_j$, so that $\{x_j,x'_j\}=\{A_j,B_j\}$. Then $x-x'=p^{2j}u$ with $u=(x_j-x'_j)+p^2w$ for an integer $w$, and $u\equiv\pm(b_j-a_j)\pmod p$. As $p\equiv1\pmod4$, $-1$ is a square modulo $p$, so $u$ is a nonzero square modulo $p$, and since $p$ is odd, Hensel's lemma makes $u$ the square of a unit modulo $p^{2\mcl-2j}$ (the remark after \cref{def:strict-square-class}). As $2j<2\mcl$, $x\ne x'$: the $2^{\mcl}$ choices give $2^{\mcl}$ distinct elements, any two of which differ by $p^{2j}$ times a unit square. A map $g\in\mathfrak G_p$ multiplies differences by the unit square $s$, so the same holds in $g(\mathcal C_p)$; and two labels $z_v=g(y_{v_0})$, $z_w=g(y_{w_0})$ are equal or two distinct elements of $g(\mathcal C_p)$. This is (iii). \emph{Invariance.} The map $g$ is uniform on the group $\mathfrak G_p$ and independent of the clique and of the $y_i$. For fixed $h\in\mathfrak G_p$, $h\circ g$ has the same properties, so $(h(g(y_i)))_i$ has the law of $(g(y_i))_i$, and the pullback $\lambda_p$ is invariant under $z\mapsto(h(z_v))_v$ (\cref{lem:slot-array}(v)(d)). The translations act transitively, so the one-slot marginals are uniform (\cref{lem:marginals}\ref{it:marg:one}). This is (ii). \emph{Positivity.} Let $\omega$ be the clique data together with $g$. Conditionally on $\omega$ the six labels $Y_i=g(y_i)$, $i\in\Zsix$, are independent and uniform on $g(\mathcal C_p)$, and $z_v=Y_{v_0}$. A chamber cut $\vartheta_{1,a}$ of the second coordinate and the cut $\iota$ do not change the first coordinate, so they fix every labelling in the support: the cut matrix of $\lambda_p$ there is nonnegative and diagonal, and $\lambda_p$ is reflection positive (\cref{lem:slot-array}(v)(a), \cref{lem:commoncut}(i)). Consider a chamber cut $\vartheta_{0,a}$ of the first coordinate, with reflection $\vartheta_a$ and plus half $W_a=\{v:v_0\in H_a\}$. The family $(Y_i)_i$ is conditionally exchangeable, so $\lambda_p$ is invariant under the reflection. A real function $F$ of the labels on $W_a$ has the form $F(z_{W_a})=\Phi((Y_i)_{i\in H_a})$, and then $F((z_{\vartheta_{0,a}v})_{v\in W_a})=\Phi((Y_{\vartheta_ai})_{i\in H_a})$. As $\vartheta_a$ maps $H_a$ onto $\Zsix\setminus H_a$, the families $(Y_i)_{i\in H_a}$ and $(Y_{\vartheta_ai})_{i\in H_a}$ are conditionally independent and identically distributed, so \[ \int F(z_{W_a})\,F\bigl((z_{\vartheta_{0,a}v})_{v\in W_a}\bigr)\,d\lambda_p(z) =\E_\omega\Bigl[\Bigl(\E\bigl[\Phi\bigl((Y_i)_{i\in H_a}\bigr)\bigm|\omega\bigr]\Bigr)^2\Bigr]\ge0 , \] which is reflection positivity at $\vartheta_{0,a}$ (\cref{def:rp}). This is (i). \emph{The exception.} The event $\mathsf E$ depends only on the first-coordinate labels and is preserved by every bijection $h\in\mathfrak G_p$; so $\lambda^{\rm ex}_p=\one_{\mathsf E}\lambda_p$ is invariant and its one-slot marginals are $\lambda^{\rm ex}_p(1)$ times the uniform law (\cref{lem:marginals}\ref{it:marg:closure}, \ref{it:marg:one}). Like $\lambda_p$, it is supported on labellings fixed by $\iota$. Off $\mathsf E$ every pair of $\mathcal Q$ has a nonzero difference, of the form stated by (iii). Conditionally on $\omega$ the $Y_i$ are independent and uniform on $2^{\mcl}$ elements, so $\Pr(Y_i=Y_{i'}\mid\omega)=2^{-\mcl}$ for $i\ne i'$; the union bound gives $\lambda^{\rm ex}_p(1)\le n2^{-\mcl}$, and if the $n$ pairs are disjoint the $n$ coincidence events involve disjoint sets of conditionally independent labels, so that $\Pr(\mathsf E^c\mid\omega)=(1-2^{-\mcl})^n$. (v) Every query of $\mathcal E_6$ has the first-coordinate pair $(0,\rot0)=(0,2)$ (\cref{def:slot-array}(e)), so $n=1$. The twelve queries have the disjoint first-coordinate pairs $\{0,2\}$ and $\{5,\rot5\}=\{5,3\}$, so $\lambda^{\rm ex}_p(1)=1-(1-2^{-\mcl})^2=\eta_{\mcl}$; and $\eta_{\mcl}-2^{-\mcl}=2^{-\mcl}-2^{-2\mcl}\ge0$. (vi) The three measures are nonnegative, invariant under $\mathfrak G_p$, so that their one-slot marginals and those of their variations are multiples of the uniform law (\cref{lem:marginals}), and they are measures of the field labels of $\{p\}$ only, so they do not depend on the interval, residue or inclusion indices: this is (O1). No sharp operator bound is applied to them (the exception is charged by its mass, \cref{lem:frontier:iidenergy}), so (O2) holds. The law does not depend on the scale; with (i) and (ii) this gives \ref{it:record:R1}--\ref{it:record:R3}, and \ref{it:record:R5} at a clique prime is (iv) for $\mathcal E_6$, with $2\mcl=e_p$. \end{proof} Outside its own atoms, the prefix enters the estimates of Part~V only through parts (i) and (ii) of \cref{lem:frontier:iidlocal}, as an unchanged tensor factor (a spectator) at other atoms. \subsection{Price of deleting coincident labels}\label{subsec:clique-price} Selecting a prefix atom fixes the full group $\Z/p^{e_p}\Z$ at every slot, so the price of a deletion is its mass times $p^{e_pa}$. With $\mcl$ digit pairs the mass is $2^{-\mcl}$, while the price factor grows only like $p^{2\mcl a}$. \begin{lemma}[The price of the prefix]\label{lem:frontier:iidenergy} Let $a>0$, $\mcl\ge1$ and $P\ge2$. Let every prime $p\equiv1\pmod4$ below $P$ be a prefix atom $\{p\}$ with $e_p=2\mcl$ and reference law $\lambda_p$, and let the comparison law at $p$ be $\nu_p=\lambda_p-\lambda^{\rm ex}_p$, where $\lambda^{\rm ex}_p$ is the exception of a family of queries with $\lambda^{\rm ex}_p(1)\le\eta_{\mcl}$ (\cref{lem:frontier:iidlocal}(iv),(v)). \begin{enumerate}[label=(\roman*)] \item The selection factor of $\{p\}$ is $p^{e_pa}=p^{2\mcl a}$: in every structured energy in which $\{p\}$ is selected it contributes the factor $p^{2\mcl a}$ to the price, density factors included; an unselected prefix atom contributes nothing. \item The change $\nu_p-\lambda_p=-\lambda^{\rm ex}_p$ is symmetric at $\iota$, and (CP4)(b) holds for it with $\zeta^{\rm s}=-\lambda^{\rm ex}_p$, $\zeta^{\rm a}=0$, $D^{\rm s}=\lambda^{\rm ex}_p/\lambda^{\rm ex}_p(1)$ and $\tilde\pi^{\rm s}=\lambda^{\rm ex}_p(1)$: the deletion is charged to the symmetric part only, at the price $\lambda^{\rm ex}_p(1)p^{2\mcl a}\le\eta_{\mcl}p^{2\mcl a}$. Its norm envelope is $\lambda^{\rm ex}_p$, and (CP6) holds at $p$ with $M_{\rm L}=M_{\rm R}=\lambda_p+\lambda^{\rm ex}_p$, at the same price. If $\lambda^{\rm ex}_p(1)=0$, omit the normalized record and take $\zeta^{\rm s}=\zeta^{\rm a}=0$ and price zero. \item The total price of the deletions is at most \[ H_{\rm iid}=\eta_{\mcl}\sum_{\substack{pX_{\rm Ch}$ put $x=\max(X,X_{\rm Ch})$, $\mathsf n=\lceil128\log_2(Y/x)\rceil$ and \[ x_j=x^{1-j/\mathsf n}Y^{j/\mathsf n},\qquad n_j=\Bigl\lfloor\frac L{\log x_{j+1}}\Bigr\rfloor\qquad(0\le j<\mathsf n). \] In the cell $[x_j,x_{j+1})$ group its primes $p\equiv3\pmod4$, in increasing order, into consecutive blocks of $n_j$ primes; the last block of the cell may have fewer. The five pieces above $X_{\rm Ch}$ have $\mathsf n=236,256,512,640,306$; their integers $n_j$ are recorded in \cref{cert:record:middle-price}. \end{enumerate} The \emph{middle blocks} are the blocks of (c) and (d). Each lies in one part or one cell, and therefore in one piece. \end{definition} No endpoint used in (c) or (d) is a prime: $X_{\rm Ch}$, the threshold points and every $Y$ are even, and an interior $x_j$ cannot be an odd prime $p$, because $p^{\mathsf n}=x^{\mathsf n-j}Y^j$ would be even. The cells and the cardinalities are deterministic functions of $L$ and of the endpoints; the bin integers are fixed rational upper logarithms. No numerical choice depends on $a$ or on $N$. \begin{remark}[Restarts and fixed cardinality] \label{rem:middle-restarts} A block never straddles a part or a cell: the partition restarts at every cut. This costs one restart term per cell in \cref{lem:record:block-charge}, but it removes every analysis of blocks that cross a boundary between pieces with different local coefficients, and it lets each piece carry its own local law. Inside a cell all blocks except the last have exactly $n_j$ primes, so the start of every later block is controlled by the full block that precedes it; this turns the sum over block starts into a sum over primes, to which the explicit Chebyshev bound is applied once, on the whole interval. The pieces need not be equally spaced: the threshold points $c'_1,c'_2,c'_3$, together with $c_{98}$, are endpoints $X_i$, so $[c_{97},c_{99})$ is the union of five consecutive pieces, each a union of parts. Each piece carries its own prime counts, product budget and restart, endpoint and jump terms; the pieces are disjoint and cover the range, so adding their charges drops no boundary term. \end{remark} \begin{lemma}[Domain of the local laws]\label{lem:record:local-domain} Let $\Blk$ be a middle block in the piece $[X,Y)$. Then: \begin{enumerate}[label=(\roman*)] \item every prime of $\Blk$ satisfies $p\equiv3\pmod4$ and $X\le b_{\Blk}\le p0$ and $s>0$. \begin{enumerate}[label=(\roman*)] \item \emph{Cells.} Let $[x,Y)$ be an interval with $x\ge X_{\rm Ch}$ and $x,Y$ even, $x_j=x^{1-j/\mathsf n}Y^{j/\mathsf n}$ for $0\le j\le\mathsf n$, and let $n_0,\dots,n_{\mathsf n-1}\ge1$ be integers. Partition the primes $p\equiv3\pmod4$ of each cell $[x_j,x_{j+1})$ into consecutive blocks of $n_j$ primes, the last possibly shorter. Put \[ \Pi_j=\exp(2an_j\log x_{j+1}),\qquad g_j=\Pi_j/n_j,\qquad I_j(s)=\int_{x_j}^{x_{j+1}}\frac{t^{-s}}{\log t}\,dt \] (numbers attached to the cells). Then, with $\mathsf e=\mathsf e_x:=2411/(5000000\log x)$, \begin{equation}\label{eq:record:cell-charge} \begin{split} \sum_{\Blk}q_{\Blk}^{2a}b_{\Blk}^{-s}\le{}&\sum_{j<\mathsf n}\Pi_jx_j^{-s} +\Bigl(\frac12+\mathsf e\Bigr)\sum_{j<\mathsf n}g_jI_j(s)\\ &+2\mathsf e\,\frac{g_0x^{1-s}}{\log x} +2\mathsf e\sum_{00$ and $t>1$), and its jump at an interior endpoint is $\Delta_j=(g_j-g_{j-1})f_s(x_j)$. With $\eta(t)=\theta(t;4,3)-t/2$, \[ \sum_jg_j\sum_{\substack{x_j\le p0}(g_j-g_{j-1})_+ \frac{x_j}{\log x_j}f(x_j). \end{align*} This functional is positive and independent of the degree $s$. Hence any pointwise polynomial inequality in $r=t^{-1/2}$ on $[x,Y]$ may be integrated against $\Phi$, including an inequality with signed coefficients. A common positive repricing factor preserves this property. \end{corollary} \begin{proof} Every displayed weight is nonnegative, and substitution of $f(t)=t^{-s}$ gives \eqref{eq:record:cell-charge}. Apply positivity to the difference of the two sides of the pointwise inequality. \end{proof} The inequality is applied before rounding. Independently rounded upper bounds for different monomials do not define the same positive functional and cannot be substituted into its negative coefficients. For the exact blocks the same principle applies to the actual common block sum; their independently rounded degree histograms supply upper bounds, not signed functional identities. The same partial summation, with the error subtracted, gives lower bounds for the unpriced start sums. \begin{lemma}[Lower start sums]\label{lem:record:lower-start-sums} \leavevmode \begin{enumerate}[label=(\roman*)] \item In the setting of \cref{lem:record:block-charge}(i), \[ \sum_{\Blk}b_{\Blk}^{-1}\ \ge\ \Bigl(\frac12-\mathsf e\Bigr) \sum_{j<\mathsf n}\frac1{n_j}\log\frac{\log x_{j+1}}{\log x_j} -2\mathsf e\Bigl(\frac1{n_0\log x} +\sum_{015$. Fix distinct $u,u'$ and an ordered pair $(x_0,x_0')$ of distinct labels outside $\{u,u'\}$. The number of ordered pairs $(x_2,x_2')$ completing an $F$-configuration lies between $(p-11)(p-15)/16$ and $(p-3)(p-7)/16$. Consequently the conditional laws of $(x_0,x_0')$ and of $(x_2,x_2')$ given $(u,u')$ under $\lambda_p(G_{\rm F,2})$ (\cref{subsec:push:layer12spectral}), relative to the uniform distinct-pair law avoiding the middle pair, have densities in $[R_2^{-1},R_2]$ with $R_2=(p-3)(p-7)/((p-11)(p-15))$. For one layer the same holds with $R_1=(p-1)/(p-3)$. \end{enumerate} \end{lemma} \begin{proof} (i) is part of \cref{lem:paley-triple}. (ii) By (i) there are $p(p-1)\lambda_0(\lambda_0-1)$ ordered outer $K_{2,2}$ embeddings $(x_0,x_0',x_2,x_2')$, with $\lambda_0=(p-3)/4$; each allows $(p-4)(p-5)$ ordered middle pairs. The maps $z\mapsto\alpha z+\beta$ with $\chi(\alpha)=1$ preserve $F$-configurations and act transitively on the ordered distinct pairs $(u,u')$ with fixed $\chi(u'-u)$. The middle labels are unconstrained, so $(u,u')$ and $(u',u)$ have the same number of completions; since $\chi(-1)=-1$, this exchange interchanges the two orbits. Hence the count is constant, equal to $\lambda_0(\lambda_0-1)(p-4)(p-5)=(p-3)(p-7)(p-4)(p-5)/16$. (iii) By (i), the common successors of $x_0,x_0'$ number $\lambda_0$; removing those among $u,u'$ leaves $\lambda_0-h$ with $0\le h\le2$. Ordered pairs of distinct ones number $(\lambda_0-h)(\lambda_0-h-1)$, which lies between $(\lambda_0-2)(\lambda_0-3)$ and $\lambda_0(\lambda_0-1)$. The conditional density of $(x_0,x_0')$ is its count divided by the mean count, so it lies in $[R_2^{-1},R_2]$. The same argument with common predecessors gives the opposite outer marginal. For one layer the successors of $x_0$ other than the middle label number $(p-1)/2$ or $(p-3)/2$, whence $R_1$. \end{proof} \begin{remark}[Why the middle range is class three]\label{rem:middle-class-three} Part (ii) fails for $p\equiv1\pmod4$: at $p=13$ the two orbits of ordered middle pairs have $312$ and $264$ completions. Part (ii) gives the $F$ and $E$ laws the same middle law, so that in the completion and in the first stage the $F$ and $E$ kernels are densities against the one conditional reference of part~(iii) (the uniform distinct-pair law given the middle pair) and the fold kernel has middle-pair density identically $1$ (\cref{rem:polarization-uses}); this is why the middle range consists of class-three primes, every class-one prime below $P_4$ being a prefix prime (\cref{lem:frontier:iidlocal}). \end{remark} \subsection{The twelve-label graphs and bounds \texorpdfstring{$-gp^{-1/2}I\preceq A_p\preceq(1+c^+/p)I$}{-g p\textasciicircum (-1/2) I <= A\_p <= (1+c+/p) I}} \label{subsec:push:layer12spectral} On a block $\Blk$ of class-three primes we write $x\to y$ if $\chi_p(y-x)=1$ at every prime $p$ of $\Blk$. The \emph{twelve-label root} $G_{\rm L,2}$, the \emph{$F$ graph} $G_{\rm F,2}$ and the \emph{$E$ graph} $G_{\rm E,2}$ are the graphs $G_{\rm L}$, $G_{\rm F}$, $G_{\rm E}$ of \cref{lem:record:fold-identification} with the layer set $\{0,1\}$, and $G_{\rm L,1}$, $G_{\rm F,1}$, $G_{\rm E,1}$ are their one-layer versions (layer set $\{0\}$). Thus $G_{\rm L,2}$ has the vertices $(u,\ell)\in\Z/6\Z\times\{0,1\}$ and the edges $(u,\ell)\to(\rot u,\ell')$ for all $u,\ell,\ell'$, the four layer lifts of each of the six rotation edges $0\to2\to4\to0$ and $1\to5\to3\to1$: $12$ vertices, $24$ edges, every degree $4$. The $F$ and $E$ graphs have three \emph{objects} $0,1,2$, each carrying one label per layer; the $F$ graphs have all the edges from the labels of object $0$ to those of object $2$ (four, respectively one), the $E$ graphs no edges. For an oriented graph $G$, $\lambda_{\Blk}(G)=\bigotimes_{p\in\Blk}\lambda_p(G)$ is the product of the uniform laws on the injective strict-square labellings (\cref{def:graphs:labeling}). \begin{lemma}[Twelve-label geometry]\label{lem:layer12-geometry} \leavevmode \begin{enumerate}[label=(\alph*)] \item The chamber reflections $u\mapsto k-u$ ($k\in\{1,3,5\}$), the translation $u\mapsto u+2$ and the layer swap $\ell\mapsto1-\ell$ map the edge set of $G_{\rm L,2}$ onto itself; the first two do the same for $G_{\rm L,1}$; the layer swap is an automorphism of $G_{\rm F,2}$ and $G_{\rm E,2}$. \item The subgraph of $G_{{\rm L},j}$ induced on the objects $0,1,2$ of the plus half $H_0$ is $G_{{\rm F},j}$, $j=1,2$. \item The subgraph of $G_{\mathfrak f,2}$ induced on the layer $\ell=0$ is $G_{\mathfrak f,1}$, $\mathfrak f\in\{\rm L,F,E\}$. \item $G_{{\rm F},j}$ and $G_{{\rm E},j}$ induce the same graph, without edges, on the object pairs $\{0,1\}$ and $\{1,2\}$. \end{enumerate} \end{lemma} \begin{proof} The chamber maps of (a) and part (b) are \cref{lem:record:fold-identification}(a),(c); the layer swap permutes the four layer lifts of every edge. (c) and (d) are read off from the definitions. The script \path{research/push_2026_10_17/sparse/layer12.py} reconstructs these facts. \end{proof} The spectral caps concern five cuts: the first-coordinate cut $\vartheta_0$ of $G_{\rm L,2}$ and of $G_{\rm L,1}$ (named L20 and L10), and the layer cut $\iota$ of $G_{\rm L,2}$, $G_{\rm F,2}$ and $G_{\rm E,2}$ (named L21, F21 and E21). Each is spectral data in the sense of \cref{def:spec:data}, with the deletion order $\mathfrak o$ of that definition fixed as in the data of \cref{cert:layer12-grid}; by \cref{lem:layer12-geometry}(b),(c) its half graph $G^+$ is $G_{{\rm F},j}$ for L20 and L10 and the one-layer graph for the three layer cuts. For a prime $p$ let $\mathsf A_p$ be the normalized cut operator of \cref{lem:spec:cutkernel} on $L^2(\lambda_p(G^+))$, so that $\E_{\lambda_p(G)}[\Phi(x)\Phi(x')]=\ip\Phi{\mathsf A_p\Phi}$ for every real function $\Phi$ on the half, $x$ and $x'$ being the half and the reflected half of a labelling; on a block, $\mathsf A_{\Blk}=\bigotimes_{p\in\Blk}\mathsf A_p$, and the same identity holds for $\lambda_{\Blk}(G)$ (\cref{lem:spec:cutkernel}(e)). Route~A (\cref{thm:spectral-criterion}) gives the caps of L21, E21, L10 and F21 (\cref{lem:layer12-caps}). The cap of L20 of the uniform root is proved directly from complete actual stars (\cref{subsec:middle-l20}); on the seven pieces from $2^{30}$ the caps of L20 and L21 of the positive root are those of \cref{sec:positive-roots}. For the folds the reference uses the cap $k_{\rm D}$ of \cref{lem:old-f-law}, not the F21 cap. \begin{lemma}[Twelve-label caps]\label{lem:layer12-caps} Let $X$ be the start of a middle piece, and for one of the cuts L21, E21, L10 and F21 let $g_X$ be the class-three negative constant and $c^+_X$ the positive constant recorded at the threshold $X$ in \cref{cert:layer12-grid}. \begin{enumerate}[label=(\alph*)] \item For every prime $p\ge X$ with $p\equiv3\pmod4$, $-g_Xp^{-1/2}I\preceq\mathsf A_p\preceq(1+c^+_X/p)I$. \item Let $\Blk$ be a middle block, with least prime $b$, of the piece starting at $X$. Then $\mathsf A_{\Blk}\succeq-g_X\exp\bigl(c^+_XL_{\rm loc}/(X\log X)\bigr)\,b^{-1/2}$. The coefficient $g_X\exp(c^+_XL_{\rm loc}/(X\log X))$ is the \emph{block cap} of the cut for the piece. \end{enumerate} The reference uses the block caps of L21 on the pieces below $2^{30}$ and those of E21 and L10 on every piece; the cap of F21 is recorded but not used. \end{lemma} \begin{proof} (a) This is route~A, \cref{thm:spectral-criterion}(a),(d) for the class $\mathfrak c=3$, with $p_0=X$ and $c^+_X$ the constant $B^+$ of (d). The spectral data satisfy (S1) at $X$: the graphs have at most twelve vertices (half-graphs on $n\le6$ vertices, in the notation of \cref{thm:spectral-criterion}) and maximum degree at most four, and $X\ge Q_3>2^{24}$, so $e_\Delta(X,2n)\le e_4(2^{24},12)<5\cdot10^{-3}$ and $X>4n^2$. The inputs (R1)--(R3) are the standard ones of \cref{rem:spectral-criterion:uses}(i): the nonstar bound of the compressed matching partition for these spectral data (\cref{cor:extraction-compressed}), the natural coincidence bound \eqref{eq:collision-natural} of \cref{lem:oct24-collision}, and the standard star and coupling inputs. The evaluator verifies the test \eqref{eq:spectral-test} in exact rational arithmetic at $X$ for both class-three signs, with one common value of $\tau^{\rm sp}_{3,\pm}$, and records $g_X$, rounded upward, as the class-three constant $g_3$ of the theorem; it computes $c^+_X$ with the largest $g$ of all four tests, which satisfies $gX^{-1/2}<1$ and is at least $g_3$, as (d) allows (\cref{rem:spectral-criterion:certificate}). (b) By \cref{lem:record:local-domain}(i),(ii), the primes of $\Blk$ satisfy $p\equiv3\pmod4$ and $p\ge X$, and $\sum_{p\in\Blk}\log p\le L\le L_{\rm loc}$. Apply \cref{cor:spectral-criterion-blocks} with its $P$ equal to $X$ and its length $L$ equal to $L_{\rm loc}$. \end{proof} \begin{certificate}[The twelve-label grids]\label{cert:layer12-grid} For each of the five cuts of the twelve-label law and each of the $35$ thresholds listed below, the constants of the Route~A criterion (\cref{thm:spectral-criterion}) have been evaluated and its four exact positive-semidefiniteness tests \eqref{eq:spectral-test} pass; every middle piece start is one of the thresholds, so these give the caps at every piece. The values are stored in two data files, built with the spectral evaluator \path{research/push_2026_10_17/sparse/layer72_spectral.py} applied to the twelve-label graphs (\path{research/push_2026_10_17/sparse/layer12_spectral.py}). The record \path{research/frontier_2026_10_17/root/middle12_grid.json}, built by \path{research/frontier_2026_10_17/root/build_middle12_grid.py}, contains $26$ thresholds: $2^{24}$, $2^{25}$, $2^{26}$, the sixteen piece starts from $79\,806\,340$ to $2^{30}$, and $2^{31}$, $2^{32}$, $2^{34}$, $2^{36}$, $2^{40}$, $2^{45}$, $2^{50}$; the replay record \path{research/frontier_2026_10_17/root/middle12_grid_replay.json} repeats its $520$ tests with fresh partitions. The record \path{research/continuation_2026_10_24/global/middle_grid_new.json}, built by \path{research/continuation_2026_10_24/global/middle_grid.py}, contains the nine piece starts $19\,951\,586$, $21\,757\,358$, $23\,726\,568$, $25\,429\,506$, $25\,874\,006$, $28\,215\,802$, $39\,903\,170$, $47\,453\,134$, $56\,431\,604$; the review record \path{research/continuation_2026_10_24/global/middle_grid_review.json} repeats its $180$ tests with fresh partitions. The two records contain the same compressed matching partition of each cut, which each review rebuilds, and, for each threshold and cut, the constants of \cref{thm:spectral-criterion} and four exact rational positive semidefiniteness tests of \eqref{eq:spectral-test} (both real class-one signs and both Hermitian class-three signs); in every record the two class-three tests use the same $\tau^{\rm sp}$. Every piece start is a threshold of one of the records: pieces $1$--$6$ and $8$--$10$ read the second, pieces $7$ and $11$--$33$ the first. The final source stores for each piece and cut the threshold $X$, the length $585$, the class-three $g$, $c^+$ and the block cap; the native check (\path{research/advance_2026_10_24/global/check_low_reference_native.py}) binds every stored route-A spectrum to the record entry at $X$, and the L20 spectrum to the endpoint $X$ of \cref{cert:l20-grid}, and recomputes the block caps; the native check of the final source verifies that its spectra are those of the source so checked, with L20 replaced by the protected collision cap at every start and with both L20 and L21 replaced on the seven middle pieces from $2^{30}$ by \cref{cert:positive-root-caps}. At $Q_3$ the class-three values of $g$ are $2.57407111$ (L21), $0.00454092$ (E21) and $1.75129044$ (L10), with block caps below $2.574071293695$, $0.004540920001$ and $1.751290440133$. The records also contain route-A constants of L20 and F21, which the reference does not use (\cref{subsec:middle-l20}; for the folds \cref{lem:old-f-law}, \cref{cert:record:old-f-cap}), and of L21 at the starts from $2^{30}$, where the root is a positive tilt (\cref{sec:positive-roots}). The finite checks are inputs of the spectral proof, not substitutes for its graph decomposition. The data are listed in \cref{tab:data:layer12-grid}. \end{certificate} \subsection{The chamber symmetry L20 for the uniform principal law}\label{subsec:middle-l20} One cut governs the middle range: the chamber reflection in the first coordinate, called L20 in the tables and certificates. The lower spectral bound (the \emph{cap}) of its operator for the twelve-label principal law is the most negative in the middle range, so it is the bound the completion has to compensate. On the middle intervals (``pieces'') starting below $2^{30}$ the principal law is the uniform law $\lambda_{\Blk}(G_{\rm L,2})$; the tilted laws of \cref{sec:positive-roots} start at $2^{30}$. This subsection bounds the L20 operator for the uniform law directly, by computing its star part exactly in its own half law (\cref{subsec:spec:actual-stars}) instead of using the general criteria of \cref{sec:spectral}. Fix a prime $p\equiv3\pmod4$. By \cref{lem:layer12-geometry}(b) the half graph of L20 is $G_{\rm F,2}$, so the half reference $\mu_p=\lambda_p(G_{\rm F,2})$ is the uniform law on injective tuples $x=(a_0,a_1,b_0,b_1,c_0,c_1)$ with $a_i\to c_j$ for all $i,j$ (the labels of the objects $0,1,2$ in the layers $0,1$; coordinates numbered $0,\dots,5$ in this order). Let $T=\mathsf A_p$ be the L20 cut operator on $L^2(\mu_p)$, $\mathcal I$ the subspace of functions invariant under the simultaneous translations $x_k\mapsto x_k+y$ ($y\in\Fp$), and $\chi^+_p=D_{\rm full}^2/L_{\rm low}^2$ the second bound of \cref{lem:record:root-marginal}(ii), with $D_{\rm full},L_{\rm low}$ as defined there. As $T\one$ is the density of the half law of the root relative to $\mu_p=\lambda_{F,p}$ (\cref{lem:spec:cutkernel}(b)), $\norm{T\one-\one}^2=\chi^2(\nu_{\mathrm L,p}\,\|\,\lambda_{F,p})\le\chi^+_p$, where $\nu_{\mathrm L,p}$ is the $\vartheta_0$-half law of $\lambda_p(G_{{\rm L},2})$. The cross pairs of the cut are the sixteen layer lifts of the four root edges $b'\to a$, $c\to b'$, $b\to a'$ and $c'\to b$ between the half $x$ and the reflected half $x'$. The \emph{soft L20 kernel} is the product over the sixteen cross pairs of the factors $1+(D_{20})_{ij}\chi(x'_j-x_i)$, without the indicator that $x$ and $x'$ have no common label (its factors are the signed factors of the cut, not the soft factors of \cref{cor:soft-kernels}), with the signed cross matrix \begin{equation}\label{eq:l20-cross-matrix} D_{20}=\begin{pmatrix} 0&0&-1&-1&0&0\\0&0&-1&-1&0&0\\ 1&1&0&0&-1&-1\\1&1&0&0&-1&-1\\ 0&0&1&1&0&0\\0&0&1&1&0&0 \end{pmatrix} \end{equation} (rows indexed by the coordinates of $x$, columns by those of $x'$; an edge $y\to y'$ means $\chi(y'-y)=1$, and $\chi(-1)=-1$). The matrix $D_{20}$ is antisymmetric. In the notation of \cref{lem:spec:expansion} the cross signs are $\varsigma_{ij}=(D_{20})_{ij}$, so $T=K_0/Z_0$ and $K_0=K_{\rm soft}-T_{\rm coll}$, where $K_{\rm soft}=\one\otimes\one+\sum_{S\ \rm star}T_S+T_{\rm ns}$ is the soft kernel as an operator on $L^2(\mu_p)$. We call $C=(a_0,a_1,c_0,c_1)$ (coordinates $0,1,4,5$) the \emph{core} of $x$ and $b=(b_0,b_1)$ (coordinates $2,3$; not the least prime $b_{\Blk}$) its \emph{pair}, write $\mathcal H=L^2_0(\Fp)$ and $\Phat=P/r$ for the normalized Paley operator, where $P$ is the Paley operator of \cref{lem:square-shift}, and use the features $V_k$, $W_S$ of \cref{subsec:spec:actual-stars} relative to $\mu_p$ and their synthesis $\mathcal F=(V_k,(W_S/r)_S)$. The signs of the core coordinates are $s=(s_0,s_1,s_4,s_5)=(-1,-1,1,1)$, as in \cref{lem:record:weighted-moment}. \begin{lemma}[Complete stars of L20]\label{lem:l20-star-matrix} Let $p\equiv3\pmod4$ and $p>15$. \begin{enumerate}[label=\textup{(\alph*)}] \item The leaf supports with at least two elements of the stars of $K_{\rm soft}$ are the twelve sets $01$, $014$, $0145$, $015$, $04$, $045$, $05$, $14$, $145$, $15$, $23$, $45$, the subsets with at least two elements of the row supports $\{2,3\}$ and $\{0,1,4,5\}$ of $D_{20}$. With the six singletons, the Hermitian matrix $M(\Phat)$ of \cref{cor:star-matrix} satisfies \[ \det(\lambda I-M(i))=\lambda^{14}(\lambda^2-4)(\lambda^2-30); \] in particular $\norm{M(i)}=\sqrt{30}$. \item Under $\mu_p$ the conditional probability of each value of a core coordinate given the other five coordinates is at most $D_j/p$ with $D_j=4/(1-15q)$, and that of a pair coordinate is $D_j/p$ with $D_j=1/(1-5q)$. Let $\Gamma_{20}$ be one plus the largest row sum of the symmetric $18\times18$ matrix, indexed by the six singletons $V_k$ and the twelve supports $S$ of part~(a) (the features $W_S/r$), whose diagonal entries are $0$ and whose off-diagonal entries are: for two supports $S\ne T$, the bound of \cref{lem:general-star}(c) with the pivot $j\in S\triangle T$ of least $D_j$; for a singleton $k$ and a support $S$, the bound of \cref{lem:general-star}(d); and for two singletons, the bound of \cref{lem:general-star}(c) applied to their pair. Then $\norm{\mathcal F}^2\le\Gamma_{20}$; $\Gamma_{20}$ is a nondecreasing function of $r$ (with $q=r^2$), and $\Gamma_{20}\to1$ as $p\to\infty$. \item For a label $z$ put \begin{gather*} \mathsf K(z,C)=\prod_{i=0,1}\bigl(1-\chi(z-a_i)\bigr) \prod_{j=0,1}\bigl(1+\chi(z-c_j)\bigr),\\ \ell(z,C)=-\chi(z-a_0)-\chi(z-a_1)+\chi(z-c_0)+\chi(z-c_1), \end{gather*} $\mathsf K_\star=\mathsf K-1-\ell$ and $(W_\star h)(x)=\E_z\mathsf K_\star(z,C)h(z)$ for $h\in\mathcal H$, and put \begin{gather*} \mathbf u=\tfrac12(V_0+V_1-V_4-V_5),\qquad \mathbf v=\tfrac1{\sqrt2}(V_2+V_3),\qquad \mathbf w=\tfrac12(V_0+V_1+V_4+V_5),\\ \mathbf e=W_{23}/r,\qquad \mathbf z=\tfrac1{\sqrt{15}}\bigl(W_\star/r-2\mathbf u\Phat\bigr). \end{gather*} Then $\mathsf K=16\cdot\one\{c_0,c_1\to z\to a_0,a_1\}$; in particular $\mathsf K$ vanishes at the core labels, $\mathsf K^2=16\mathsf K$, $\mathsf K\ell=4\mathsf K$ and $\E_z\ell^2=4$. The function $\mathsf K_\star$ is the signed sum $\sum_S\sigma_S\psi_S$ of the eleven higher stars on the core, $\sigma_S=\prod_{k\in S}s_k$, $\psi_S(z,x)=\prod_{k\in S}\chi(z-x_k)$, and the doubly centred complete star part of $K_{\rm soft}$ is \begin{equation}\label{eq:l20-rank4-operator} T_\star=r\bigl\{\sqrt{30}(\mathbf v\mathbf z^*+\mathbf z\mathbf v^*) +2(\mathbf w\mathbf e^*+\mathbf e\mathbf w^*)\bigr\}. \end{equation} \end{enumerate} \end{lemma} \begin{proof} (c) For $z$ outside the core each factor of $\mathsf K$ is $0$ or $2$, and all four are $2$ exactly when $\chi(z-a_i)=-1$ and $\chi(z-c_j)=1$ for all $i,j$, that is, when $z\to a_i$ and $c_j\to z$. At $z=a_i$ the factor $1+\chi(a_i-c_j)$ vanishes, because $a_i\to c_j$ and $\chi(-1)=-1$; at $z=c_j$ the factor $1-\chi(c_j-a_i)$ vanishes. Hence $\mathsf K\in\{0,16\}$, $\mathsf K^2=16\mathsf K$, and $\ell=4$ where $\mathsf K\ne0$. Since $\E_z\chi(z-y)\chi(z-y')=\one_{y=y'}-q$ \eqref{eq:two-root} and $\sum_ks_k=0$, $\E_z\ell^2=4(1-q)+4q=4$. Expanding the product, $\mathsf K=\sum_S\sigma_S\psi_S$ over all $S\subseteq\{0,1,4,5\}$; the empty set gives $1$ and the singletons give $\ell$, so $\mathsf K_\star$ is the sum over the eleven sets with at least two elements. (a) and \eqref{eq:l20-rank4-operator}. By \cref{cor:star-matrix}, $M(\Phat)$ has the singleton block $D_{20}\otimes\Phat$, the entry $(-1)^{|S|}\prod_{j\in S}(D_{20})_{kj}$ at (singleton $k$, support $S$) and $\prod_{i\in S}(D_{20})_{ij}$ at (support $S$, singleton $j$). The leaf sets of the left stars are the subsets of the row supports of $D_{20}$, those of the right stars the subsets of its column supports, and these are the same because $D_{20}$ is antisymmetric; this gives the twelve supports. In $\C^{18}$, with the coordinate vectors $e_k$ ($0\le k\le5$) and $e_S$, put, at the phase $\Phat=i$, \begin{gather*} \hat{\mathbf u}=\tfrac12(e_0+e_1-e_4-e_5),\quad \hat{\mathbf v}=\tfrac1{\sqrt2}(e_2+e_3),\quad \hat{\mathbf w}=\tfrac12(e_0+e_1+e_4+e_5),\quad \hat{\mathbf e}=e_{23},\\ \hat{\mathbf z}=\tfrac1{\sqrt{15}}\Bigl(\sum_S\sigma_Se_S-2i\,\hat{\mathbf u}\Bigr), \end{gather*} the sum over the eleven supports contained in $\{0,1,4,5\}$. The four vectors $\hat{\mathbf v},\hat{\mathbf z},\hat{\mathbf w},\hat{\mathbf e}$ are orthonormal ($|\hat{\mathbf z}|^2=(11+4)/15$), and \[ M(i)=\sqrt{30}\bigl(\hat{\mathbf v}\hat{\mathbf z}^*+\hat{\mathbf z}\hat{\mathbf v}^*\bigr) +2\bigl(\hat{\mathbf w}\hat{\mathbf e}^*+\hat{\mathbf e}\hat{\mathbf w}^*\bigr), \] as a comparison of entries shows: on the right the singleton entries are $i$ at $(b_l,a_k)$ and $(c_k,b_l)$ and $-i$ at $(b_l,c_k)$ and $(a_k,b_l)$, which are those of $iD_{20}$; the entries at $(b_l,S)$ and $(S,b_l)$, $S\subseteq \{0,1,4,5\}$, are $\sigma_S=(-1)^{|S|}\prod_{j\in S}(D_{20})_{2j} =\prod_{i\in S}(D_{20})_{i2}$; the entries at $(k,23)$ and $(23,k)$, $k$ a core coordinate, are $1=(D_{20})_{k2}(D_{20})_{k3}$; and all other entries vanish on both sides, since a core row of $D_{20}$ has the support $\{2,3\}$ and a pair row the support $\{0,1,4,5\}$. So $M(i)$ has the eigenvalues $\pm\sqrt{30}$ and $\pm2$ on the span of the four vectors and $0$ on its orthogonal complement, which is (a). The synthesis maps $e_k$ to $V_k$ and $e_S$ to $W_S/r$, the phase acting as $\Phat$ on the label input; it maps $\hat{\mathbf v}$, $\hat{\mathbf w}$, $\hat{\mathbf e}$ to $\mathbf v$, $\mathbf w$, $\mathbf e$, and $\hat{\mathbf z}$ to $\mathbf z$, since $\sum_S\sigma_SW_S=W_\star$ by (c). The identity $T_\star=r\mathcal FM(\Phat)\mathcal F^*$ of \cref{cor:star-matrix} is therefore \eqref{eq:l20-rank4-operator}. (b) The coordinate $a_0$ is a common predecessor of $c_0,c_1$ distinct from $a_1,b_0,b_1$. By \cref{lem:record:class-three}(i) two distinct labels have exactly $(p-3)/4$ common predecessors, so given the other coordinates $a_0$ is uniform on at least $(p-3)/4-3=(p-15)/4$ labels; the same holds for $a_1$ and, with common successors of $a_0,a_1$, for $c_0,c_1$. A pair coordinate is uniform on the $p-5$ labels outside the other five. This gives the $D_j$. The off-diagonal Grams of $\mathcal F$ are bounded by the entries of the matrix (\cref{lem:general-star}(c),(d)), the diagonal ones are at most one (\cref{lem:general-star}(a)), and \cref{lem:general-star}(f) gives $\norm{\mathcal F}^2\le\Gamma_{20}$. Every entry is built from $q$, $r$ and $D_j-1\in\{(3+15q)/(1-15q),\,5q/(1-5q)\}$ by sums, products, square roots and division by $1-q$, so it is admissible (\cref{lem:majorant}) and tends to $0$. \end{proof} The synthesis bound $\norm{\mathcal F}^2\le\Gamma_{20}$ alone gives the coefficient $\sqrt{30}\,\Gamma_{20}$ of $r$ in the negative cap; its excess over $\sqrt{30}$ is of order $r$, with a large coefficient coming from the overlaps of the eighteen features. The following propositions separate the translation-invariant part of the kernel (\cref{prop:l20-completion}), replace this synthesis bound by the exact Gram matrices of the four features of \eqref{eq:l20-rank4-operator}, so that the leading coefficient becomes $\sqrt{30}+O(q)$ (\cref{prop:l20-rank4}), and factor the root through a rectangular kernel whose nonstar part is priced quadratically (\cref{prop:l20-rectangular,prop:l20-pair-gap}). What remains of order $r$ is the collision cap (\cref{prop:l20-collisions} and the remark after it). \begin{proposition}[Translation sectors]\label{prop:l20-completion} Let $p\equiv3\pmod4$, $p\ge2^{20}$, let $N_{\rm ns}$ and $D_{\rm col}$ be raw nonstar and collision caps of the soft L20 kernel (``raw'': bounds for the unnormalized kernel $K_0$, before division by $Z_0$), $\norm{T_{\rm ns}}\le N_{\rm ns}$ and $\norm{T_{\rm coll}}\le D_{\rm col}$ (\cref{cor:extraction-compressed,lem:oct24-collision}), let $m_\star$ be the averaged-star mean bound of \cref{lem:l20-star-mean}, and put $\eps_Z=N_{\rm ns}+D_{\rm col}+m_\star$ and $H_{20}=(N_{\rm ns}+D_{\rm col})/(1-\eps_Z)$, assuming $\eps_Z<1$. Then $T$ preserves $\mathcal I$ and $\mathcal I^\perp$, the ranges of the features $V_k$, $W_S$ lie in $\mathcal I^\perp$, and the centred block of $T$ on $\mathcal I\cap\one^\perp$ has norm at most $H_{20}$. If moreover $H_{20}<1$ and $C_\perp<1$ satisfy $T\succeq-C_\perp I$ and $\norm{T|_{\mathcal I^\perp}}\le C_\perp$, then \begin{equation}\label{eq:l20-caps} -g\,rI\preceq T\preceq(1+c^+/p)I,\qquad g=C_\perp/r,\qquad c^+=\frac{p\chi^+_p}{1-H_{20}}. \end{equation} \end{proposition} \begin{proof} By \cref{lem:spec:expansion}, $T=K_0/Z_0$ with $Z_0=\ip\one{K_0\one}_{\mu_p}$, and by \cref{lem:l20-star-mean} the star means of $K_{\rm soft}$ sum to at most $m_\star$ in modulus, so $Z_0\ge1-\eps_Z>0$. The simultaneous translations preserve $\mu_p$ and $K_0$, so $T$ commutes with them and preserves $\mathcal I$, and $\mathcal I^\perp$ as it is self-adjoint. The ranges of the features lie in $\mathcal I^\perp$ by \cref{lem:general-star}. Let $h,h'\in\mathcal I\cap\one^\perp$. Then $\E_{\mu_p}[h\mid x_k]=0$ for every coordinate $k$ (\cref{lem:spec:affpair}(d)), so $T_Sh=0$ for every column star $S$ (\cref{lem:spec:stars}(a)) and $\ip{h'}{T_Sh}=\ip{T_{S^{\mathsf t}}h'}h=0$ for every row star (\cref{lem:spec:stars}(b)); also $(\one\otimes\one)h=0$. By \eqref{eq:record:root-kernel}, $\ip{h'}{K_0h}=\ip{h'}{(T_{\rm ns}-T_{\rm coll})h}$, of modulus at most $(N_{\rm ns}+D_{\rm col})\norm h\norm{h'}$, and division by $Z_0$ bounds the centred block by $H_{20}$. The vector $T\one-\one$ is translation invariant and orthogonal to $\one$, as $\ip\one{T\one}=1$, and its squared norm is at most $\chi^+_p$. Now \cref{prop:matching:positive}(a$''$), for the group of translations, gives $T\preceq\max\bigl(C_\perp,1+\chi^+_p/(1-H_{20})\bigr)I=(1+c^+/p)I$, as $C_\perp<1$. The lower bound is the hypothesis. \end{proof} The lower bound is required on the whole space; \cref{prop:l20-rectangular} supplies it. \begin{proposition}[Gram bounds for the four L20 star features]\label{prop:l20-rank4} Let $p\equiv3\pmod4$, $p\ge2^{20}$, let $\bar{\mathsf K}(C)=\E_z\mathsf K(z,C)$, $m_{\mathsf K}=\E_{\mu_p}\bar{\mathsf K}-1$ and $v_{\mathsf K}=\E_{\mu_p}(\bar{\mathsf K}-1)^2$, let $m_\star$ be the bound of \cref{lem:l20-star-mean}, and put \begin{gather*} \mathfrak m_+=2q+\tfrac14m_\star,\qquad g_{\mathbf z}=\frac{1+\frac{14}{15}\mathfrak m_+}{1-q},\qquad \rho=\frac{(12+8r)q^2}{(1-4q)(1-5q)},\\ \rho_{\mathbf v\mathbf z}=\frac{4\sqrt{2/15}\,qr(1+\mathfrak m_+)}{(1-4q)(1-q)},\qquad \rho_{\mathbf v\mathbf w}=\frac{2\sqrt2\,q}{1-q},\qquad \rho_{\mathbf v\mathbf e}=\frac{\sqrt2\,qr}{1-q},\\ \rho_{\mathbf z\mathbf w}=\frac{2r(1+\mathfrak m_+)}{\sqrt{15}(1-q)},\qquad \rho_{\mathbf z\mathbf e}=\sqrt{g_{\mathbf z}}\,\rho,\qquad k_{\rm top}=\sqrt{30}\,(g_{\mathbf z}+\rho_{\mathbf v\mathbf z}),\qquad k_{\rm low}=2(1+\rho),\\ k_\times^2=2\sqrt{30}\bigl(\rho_{\mathbf v\mathbf w}^2+\rho_{\mathbf v\mathbf e}^2 +\rho_{\mathbf z\mathbf w}^2+\rho_{\mathbf z\mathbf e}^2\bigr),\qquad k_4=k_{\rm top}+\frac{k_\times^2}{\sqrt{30}-k_{\rm low}}. \end{gather*} Then $\sqrt{30}-k_{\rm low}>0$, $|m_{\mathsf K}|\le\mathfrak m_+$, and on $\mathcal H$: \begin{enumerate}[label=\textup{(\alph*)}] \item $\mathbf u^*\mathbf u=\frac1{1-q}I$, $\mathbf w^*\mathbf w=\frac{1-4q}{1-q}I$, $\mathbf u^*\mathbf w=\frac{2r}{1-q}\Phat$ and $\mathbf v^*\mathbf v=\frac{1-2q}{1-q}I$; \item $W_\star^*W_\star=\frac{q(11+6m_{\mathsf K}-v_{\mathsf K})}{1-q}I$, $\mathbf u^*W_\star=-\frac{2m_{\mathsf K}r}{1-q}\Phat$ and $\mathbf w^*W_\star=\frac{2q(1-m_{\mathsf K})}{1-q}I$; \item $\mathbf z^*\mathbf z=\frac{15+14m_{\mathsf K}-v_{\mathsf K}}{15(1-q)}I \preceq g_{\mathbf z}I$, $\mathbf w^*\mathbf z=-\frac{2r(1+m_{\mathsf K})}{\sqrt{15}(1-q)}I$, $\mathbf v^*\mathbf z=\frac{4\sqrt{2/15}\,qr(1+m_{\mathsf K})}{(1-4q)(1-q)}I$ and $\mathbf v^*\mathbf w=-\frac{2\sqrt2\,q}{1-q}I$; \item $\mathbf e^*\mathbf e=\frac{1-2q-q^2}{1-q}I$, $\mathbf v^*\mathbf e=\frac{\sqrt2\,qr}{1-q}I$, $\norm{\mathbf w^*\mathbf e}\le\rho$ and $\norm{\mathbf z^*\mathbf e}\le\rho_{\mathbf z\mathbf e}$. \end{enumerate} Consequently, if $\mathfrak F=(\mathbf v,\mathbf z,\mathbf w,\mathbf e)$ and $\Xi$ is a real symmetric $4\times4$ matrix with $-\Delta_\star\preceq\Xi\preceq\Delta_\star$, $\Delta_\star=\operatorname{diag}(\sqrt{30},\sqrt{30},2,2)$, then $\norm{\mathfrak F\Xi\mathfrak F^*}\le k_4$. In particular $\norm{T_\star}\le k_4r$. \end{proposition} \begin{proof} For $p\ge2^{20}$, $\rho<1/2$, so $k_{\rm low}<3<\sqrt{30}$. \emph{The mean.} By \cref{lem:l20-star-matrix}(c), $\bar{\mathsf K}-1=\sum_S\sigma_Sw_S$ over the eleven higher supports $S$ on the core, with $w_S(C)=\E_z\psi_S(z,x)$. The six two-element supports have $w_S=-q$ \eqref{eq:two-root} and $\sum\sigma_S=\frac12((\sum_ks_k)^2-4)=-2$, which contributes $2q$. Under $\mu_p$ the core is uniform on the admissible quadruples of \cref{lem:record:weighted-moment} (each has exactly $(p-4)(p-5)$ completions by the pair), whose probability under independent uniform labels is $Z_4/16$ with $Z_4=(1-q)(1-3q)(1-7q)$, while $P_{\rm adm}D_4=16$ on them ($D_4$ the indicator that the four labels are distinct, and $P_{\rm adm}$ the product of \cref{lem:record:weighted-moment}, $16$ on admissible quadruples and $0$ on the other distinct quadruples). In the notation of \cref{lem:l20-star-mean} the three- and four-element supports therefore contribute $\E_{\mu_p}[\mathcal W_3/p]=0$ and $\E_{\mu_p}[\mathcal W_4/p]=(M_{G_5}+8q^2-33q^3+25q^4)/Z_4$ \eqref{eq:l20-star-identities}, and $|M_{G_5}|\le(1-q)(q^2+2qr)$ (\cref{lem:record:weighted-moment}(b)) gives $|m_{\mathsf K}-2q|\le m_\star/4$. \emph{The Grams.} Each operator below commutes with the square-affine maps acting on the label input and on all coordinates, so on $\mathcal H$ it is $\alpha I+\gamma\Phat$, where $\alpha$ is its trace divided by $p-1$ and $\gamma(p-1)$ is the trace of its product with $\Phat^*$; if it is self-adjoint, $\gamma=0$ (\cref{lem:spec:affpair}(d)). For an orthonormal basis $(h)$ of $\mathcal H$, $\sum_hh(y)h(y')=p\one_{y=y'}-1$, which gives the traces. (a) Two core coordinates on the same side form a uniform distinct pair, and $(a_i,c_j)$ a uniform directed pair, so $V_k^*V_{k'}=-\frac q{1-q}I$ for a same-side pair and $V_{a_i}^*V_{c_j}=-\frac q{1-q}I+\frac r{1-q}\Phat$. The coefficients of $\mathbf u$ sum to zero, and the Paley parts of $V_{a_i}^*V_{c_j}$ and $V_{c_j}^*V_{a_i}$ cancel in $\mathbf u^*\mathbf u$ and $\mathbf w^*\mathbf w$ and add up in $\mathbf u^*\mathbf w$; this gives (a) for $\mathbf u$ and $\mathbf w$. The pair $(b_0,b_1)$ is a uniform distinct pair, which gives $\mathbf v^*\mathbf v$. (b) By \cref{lem:l20-star-matrix}(c), $\E_z\mathsf K_\star^2=16\bar{\mathsf K}+1+4-2\bar{\mathsf K}-8\bar{\mathsf K} =6\bar{\mathsf K}+5$ and $\E_z\mathsf K_\star=\bar{\mathsf K}-1$, so the trace of $W_\star^*W_\star$ is $\E_{\mu_p}\Var_z\mathsf K_\star=11+6m_{\mathsf K}-v_{\mathsf K}$. For a core coordinate $k$, $\mathsf K(x_k,C)=0$ and $\ell(x_k,C)=-2\pm\chi(x_k-x_{k'})$, $k'$ the other coordinate on the same side, so $\E_{\mu_p}\mathsf K_\star(x_k,C)=1$ by the exchange of $x_k$ and $x_{k'}$, and the trace of $V_k^*W_\star$ is $1-m_{\mathsf K}$. Where $\mathsf K\ne0$, $\chi(z-x_k)=s_k$, and $\E_z\chi(z-x_k)\ell=s_k$; so $\E_z\chi(z-x_k)\mathsf K_\star=s_k(\bar{\mathsf K}-1)$ and $V_k^*W_\star=\frac{q(1-m_{\mathsf K})}{1-q}I+\frac{s_km_{\mathsf K}r}{1-q}\Phat$. Summing with the coefficients of $\mathbf u$ and of $\mathbf w$ gives (b). (c) By (a), (b), $\Phat^2=-I$ and $\Phat^*=-\Phat$ on $\mathcal H$, $15\,\mathbf z^*\mathbf z=W_\star^*W_\star/q+8m_{\mathsf K}(1-q)^{-1}I +4\,\mathbf u^*\mathbf u$ and $\sqrt{15}\,\mathbf w^*\mathbf z=\mathbf w^*W_\star/r-2\mathbf w^*\mathbf u\Phat$; this gives $\mathbf z^*\mathbf z$ and $\mathbf w^*\mathbf z$, and $\mathbf z^*\mathbf z\preceq g_{\mathbf z}I$ as $v_{\mathsf K}\ge0$. Given the core, each pair coordinate is uniform on the $p-4$ labels outside it, so $\E_{\mu_p}[h(b_l)\mid C]=-2(\mathbf wh)(C)/(p-4)$ for $h\in\mathcal H$; hence $\mathbf v^*Y=-\frac{2\sqrt2\,q}{1-4q}\mathbf w^*Y$ for every operator $Y$ with values in the functions of the core, and $Y=\mathbf w,\mathbf z$ give $\mathbf v^*\mathbf w$ and $\mathbf v^*\mathbf z$. (d) \Cref{lem:general-star}(a) with $w_{23}=-q$ gives $\mathbf e^*\mathbf e$. The trace of $V_2^*W_{23}$ is $\E[\chi(0)\chi(b_0-b_1)]+q=q$, and the trace of its product with $\Phat^*$ is $r^{-1}\E\,\E_z\chi(z-b_0)^2\chi(z-b_1) =-qr^{-1}\E\chi(b_0-b_1)=0$; so $V_2^*W_{23}=V_3^*W_{23}=\frac{q^2}{1-q}I$, which gives $\mathbf v^*\mathbf e$. Given the core, $(b_0,b_1)$ is uniform on the ordered distinct pairs outside it, and expanding $\sum_{y\ne y'}\chi(z-y)\chi(z-y')$ over such pairs gives, on $\mathcal H$, \[ \E_{\mu_p}[W_{23}\mid C]=\frac{-2q\sum_kV_k+2\sum_{|S|=2}W_S}{(p-4)(p-5)}, \] the sums over the core coordinates and over the six two-element subsets of the core. As $\norm{V_k}=1$ and $\norm{W_S}\le r$ (\cref{lem:general-star}(a)), the conditional expectation $\Pi_C\mathbf e$ of $\mathbf e$ onto the functions of the core has norm at most $\rho$. For $Y=\mathbf w,\mathbf z$, which take values in the functions of the core, $\mathbf e^*Y=(\Pi_C\mathbf e)^*Y$, and $\norm{\mathbf w}\le1$, $\norm{\mathbf z}\le\sqrt{g_{\mathbf z}}$. \emph{The consequence.} As $-\Delta_\star\preceq\Xi\preceq\Delta_\star$, $\norm{\mathfrak F\Xi\mathfrak F^*}\le\norm{\mathfrak F\Delta_\star\mathfrak F^*} =\norm{\Delta_\star^{1/2}\mathfrak G\Delta_\star^{1/2}}$, where $\mathfrak G=\mathfrak F^*\mathfrak F$ is the Gram of the four features. In the blocks $(\mathbf v,\mathbf z)$ and $(\mathbf w,\mathbf e)$ this matrix has diagonal blocks of norms at most $k_{\rm top}$ and $k_{\rm low}$, by (a)--(d), and an off-diagonal block of squared norm at most $k_\times^2$, the weighted sum of the squared norms of its four entries. Since $k_{\rm top}\ge\sqrt{30}>k_{\rm low}$, the largest eigenvalue of $\bigl(\begin{smallmatrix}k_{\rm top}&k_\times\\k_\times&k_{\rm low}\end{smallmatrix}\bigr)$, at most $k_{\rm top}+k_\times^2/(k_{\rm top}-k_{\rm low})\le k_4$, bounds the norm. By \eqref{eq:l20-rank4-operator}, $T_\star/r=\mathfrak F\Xi_\star\mathfrak F^*$ with $\Xi_\star=\bigl(\begin{smallmatrix}0&\sqrt{30}\\\sqrt{30}&0\end{smallmatrix}\bigr) \oplus\bigl(\begin{smallmatrix}0&2\\2&0\end{smallmatrix}\bigr)$, and $-\Delta_\star\preceq\Xi_\star\preceq\Delta_\star$. \end{proof} The coefficient $k_4$ is $\sqrt{30}+O(q)$: the only overlap of order $r$, the entry $\rho_{\mathbf z\mathbf w}$ between the two blocks, enters quadratically across the gap $\sqrt{30}-2$. \begin{proposition}[The soft L20 kernel as a swapped rectangle product]\label{prop:l20-rectangular} Let $p\equiv3\pmod4$, $p\ge2^{20}$. Let $\mu^{\rm core}$ be the uniform law on the admissible cores $C$ (distinct labels with $a_i\to c_j$) and $\mu^{\rm pair}$ the uniform law on the ordered distinct pairs $b$, and let $\mathsf R\colon L^2(\mu^{\rm pair})\to L^2(\mu^{\rm core})$ have the kernel $\mathsf R(C;b)=\mathsf K(b_0,C)\mathsf K(b_1,C)$; the features $\mathbf z,\mathbf w$ of the core and $\mathbf v,\mathbf e$ of the pair are those of \cref{lem:l20-star-matrix}, read in these laws. \begin{enumerate}[label=\textup{(\alph*)}] \item $\mathsf R$ has the row mass $\mathfrak r(C)=\mathsf R\one(C)=(\bar{\mathsf K}(C)^2-16q\bar{\mathsf K}(C))/(1-q)$ and a constant column mass, and $\mathsf R_c=\mathsf R-\mathfrak r\otimes\one$ (where $(\mathfrak r\otimes\one)h=(\E h)\,\mathfrak r$) satisfies $\mathsf R_c\one=\mathsf R_c^*\one=0$ and $\mathsf R_c^*\mathfrak r=0$. \item Let $N_A$ be an upper bound for the norm of the double-centred nonstar remainder $P_0(\text{nonstars})P_0$. A raw cap from \cref{cor:soft-kernels}(a) suffices; the sharper bound of \cref{thm:rectangle-gram} also applies. Then \begin{equation}\label{eq:l20-rectangle} \mathsf R=\mathfrak r\otimes\one+\mathsf R_\star+\mathsf R_\circ,\qquad \mathsf R_\star=r\bigl(\sqrt{30}\,\mathbf z\mathbf v^*+2\mathbf w\mathbf e^*\bigr),\qquad \norm{\mathsf R_\circ}\le N_A , \end{equation} and $\norm{\mathsf R_\star}\le k_4r$; hence $\norm{\mathsf R_c}\le k_4r+N_A$. \item On $L^2(\mu^{\rm core}\otimes\mu^{\rm pair})$ the soft L20 kernel is \begin{equation}\label{eq:l20-swap} K_{\rm soft}\bigl((C,b),(C',b')\bigr)=\mathsf R(C;b')\,\mathsf R(C';b),\qquad K_{\rm soft}=T[\mathsf R,\mathsf R]=(\mathsf R\otimes\mathsf R^*)\operatorname{Swap}. \end{equation} \item Put $\eta=2q+11r$, $h_p=(1-4q)(1-5q)/(1-q)$ and \[ s_p=\frac{\bigl[1+4\mathfrak m_++(6+4\eta+\eta^2)\eta^2 +256q^2(1+2\mathfrak m_++\eta^2)\bigr]^{1/2}}{1-q}. \] Then $\norm{\mathfrak r}\le s_p$. If $\norm{\mathsf R_c}\le c_{\rm R}<1$, then for every collision cap $D_{\rm col}$ with $\eps_Z=N_{\rm ns}+D_{\rm col}+m_\star<1$ as in \cref{prop:l20-completion}, \[ T\succeq-C'I,\qquad\norm{T|_{\mathcal I^\perp}}\le C',\qquad C'=\frac{s_pc_{\rm R}/h_p+D_{\rm col}}{1-\eps_Z}. \] \end{enumerate} \end{proposition} \begin{proof} (a) Given $C$, under $\mu^{\rm pair}$, $\mathfrak r(C)=\frac1{p(p-1)}\sum_{y\ne y'} \mathsf K(y,C)\mathsf K(y',C)=\frac{p^2\bar{\mathsf K}^2-\sum_y\mathsf K(y,C)^2}{p(p-1)}$, which is the stated formula by $\mathsf K^2=16\mathsf K$. If $\varphi$ is a function of the core invariant under the square-affine maps, then $\mathsf R^*\varphi(b)=\E_{\mu^{\rm core}}[\mathsf R(C;b)\varphi(C)]$ is invariant under these maps acting on $b$, hence constant on each of the two orbits of ordered distinct pairs (the sign of $\chi(b_1-b_0)$); $\mathsf R$ is symmetric in $b_0,b_1$, and the exchange maps one orbit onto the other because $\chi(-1)=-1$, so $\mathsf R^*\varphi$ is constant. With $\varphi=\one$ and $\varphi=\mathfrak r$ this gives the constant column mass $\E\mathfrak r$ and $\mathsf R^*\mathfrak r=\norm{\mathfrak r}^2\one$; hence $\mathsf R_c\one=0$, $\mathsf R_c^*\one=0$ and $\mathsf R_c^*\mathfrak r=0$. (b) By (a), $\mathsf R_c=P_0\mathsf RP_0$, with $P_0$ the projections onto the mean-zero functions. Expand $\mathsf R=\prod(1+s_k\chi(b_l-x_k))$ over the eight cross pairs (core coordinate $k$, pair coordinate $b_l$) into its $256$ subset terms: the constant, $34$ stars ($8$ single pairs, $22$ sets of at least two pairs at one pair coordinate and $4$ pairs $\{(k,b_0),(k,b_1)\}$ at one core coordinate) and $221$ nonstars. The double centring removes the constant. The stars at $b_l$ add up to $(\ell+\mathsf K_\star)(b_l,C)$, and $\E_z\ell(z,C)h(z)=\sum_ks_k(Ph)(x_k)=-2r(\mathbf u\Phat h)(C)$; so after the double centring they give $(W_\star-2r\mathbf u\Phat)V^*_{b_l}=\sqrt{15}\,r\,\mathbf zV^*_{b_l}$, with $V_{b_l}h=h(b_l)$; the stars at the core coordinates give $\sum_kV_kW_{23}^*=2r\mathbf w\mathbf e^*$, their rank-one marginal terms being exactly those removed by the double centring (\cref{cor:star-matrix}). Hence the centred stars give $\sqrt{15}\,r\,\mathbf z(V^*_{b_0}+V^*_{b_1})+2r\mathbf w\mathbf e^*=\mathsf R_\star$, and $\mathsf R_\circ=P_0(\text{nonstars})P_0$ has norm at most that of the sum of the nonstar terms. The raw extraction bound of \cref{cor:soft-kernels}(a) also bounds this compression: the core and pair coordinate embeddings are isometries, and the eight-edge kernel uses the same $221$ subsets. The sharper direct calculation is \cref{thm:rectangle-gram}. Finally $\mathsf R_\star$ maps the mean-zero functions of the pair to those of the core. Its Hermitian dilation on $L^2(\mu^{\rm core})\oplus L^2(\mu^{\rm pair})$ is $r\mathfrak F'\Xi_\star\mathfrak F'^*$ for the four features placed in their summands; their Gram has the blocks of \cref{prop:l20-rank4} inside each summand ($\mathbf z,\mathbf w$ depend only on the core and $\mathbf v,\mathbf e$ only on the pair, whose laws under $\mu_p$ are $\mu^{\rm core}$ and $\mu^{\rm pair}$) and zero blocks across them. The argument of \cref{prop:l20-rank4} gives $\norm{\mathsf R_\star}\le k_4r$. (c) The cross factors between the core of $x$ and the pair of $x'$ are $1-\chi(b'_l-a_i)$ and $1+\chi(b'_l-c_j)$, the entries $-1$ and $1$ of $D_{20}$ in the rows of $a_i$ and $c_j$; their product is $\mathsf R(C;b')$. By the antisymmetry of $D_{20}$ the factors between the pair of $x$ and the core of $x'$ are $1+\chi(a'_i-b_l)=1-\chi(b_l-a'_i)$ and $1-\chi(c'_j-b_l)=1+\chi(b_l-c'_j)$, with product $\mathsf R(C';b)$, and $D_{20}$ has no other nonzero entries. The second form is \cref{lem:swapped-rectangle}(a). (d) Write $\bar{\mathsf K}=1+y$. By \cref{lem:l20-star-matrix}(c) and \cref{thm:weil}, $|y|\le2q+4\cdot2r+3r=\eta$ (six two-root, four three-root and one four-root sum), and $\E_{\mu^{\rm core}}y=m_{\mathsf K}\le\mathfrak m_+$ (\cref{prop:l20-rank4}). Hence $\E\bar{\mathsf K}^4\le1+4\mathfrak m_++(6+4\eta+\eta^2)\eta^2$ and $\E\bar{\mathsf K}^2\le1+2\mathfrak m_++\eta^2$, and dropping the term $-32q\bar{\mathsf K}^3\le0$ in $(1-q)^2\mathfrak r^2$ gives $\norm{\mathfrak r}\le s_p$; note $s_p\ge1$. By (a), $\mathsf R$ has the singular pair $(\mathfrak r/\norm{\mathfrak r},\one)$ with the value $\norm{\mathfrak r}$, and all its other singular values are at most $c_{\rm R}$. By \cref{lem:swapped-rectangle}(a) the eigenvalues of $T[\mathsf R,\mathsf R]$ are $0$, the squares of the singular values and their products $\pm\sigma_i\sigma_j$ ($i\ne j$); as $c_{\rm R}<1\le s_p$, all negative eigenvalues are at least $-s_pc_{\rm R}$, and all eigenvalues except the one at the translation-invariant vector $(\mathfrak r/\norm{\mathfrak r})\otimes\one$ have modulus at most $s_pc_{\rm R}$. The law $\mu_p$ is $\mu^{\rm core}\otimes\mu^{\rm pair}$ conditioned on the translation-invariant event $\mathcal E$ that the pair avoids the core, which has probability $h_p$ for every core. With the isometry $Jf=\one_{\mathcal E}f/\sqrt{h_p}$ of $L^2(\mu_p)$ into $L^2(\mu^{\rm core}\otimes\mu^{\rm pair})$, $K_{\rm soft}=h_p^{-1}J^*T[\mathsf R,\mathsf R]J$ on $L^2(\mu_p)$, and $J$ maps $\mathcal I^\perp$ into the orthogonal complement of the translation-invariant functions. So $K_{\rm soft}\succeq-(s_pc_{\rm R}/h_p)I$ and $\norm{K_{\rm soft}|_{\mathcal I^\perp}}\le s_pc_{\rm R}/h_p$. Finally $T=(K_{\rm soft}-T_{\rm coll})/Z_0$ with $\norm{T_{\rm coll}}\le D_{\rm col}$ and $Z_0\ge1-\eps_Z$ (proof of \cref{prop:l20-completion}). \end{proof} % Begin sections/20a_rectangle_gram \subsubsection{Bounding the centred remainder through its Gram} The $221$ nonstar terms of the rectangle share their four core variables. Estimating the Gram of their sum retains cancellations that are lost when the $221$ terms are bounded separately and their norms are then added. The following estimate is for precisely $\mathsf R_\circ$ in \eqref{eq:l20-rectangle}. \begin{lemma}[Two-sided bounds for the squared cubic trace $H_u$]\label{lem:rectangle-mellin} For $u\in\Fp$, on counting measure on $\Fp\setminus\{u\}$, put \[ T_u(v,w)=\E_y\chi(u-y)\chi(v-y)\chi(w-y),\qquad H_u=T_u\circ T_u. \] Then $\|T_u\|\le1$, $\|H_u\|\le1-2q-2q^2$, and \[ H_u\succeq-(3r+q-q^2)I. \] \end{lemma} \begin{proof} The full character matrix $C$ satisfies $CC^*=pI-J$. The matrix $T_u$ is a compression of $qC\diag(\chi(u-y))C^*$, so has norm at most $1$. Character orthogonality gives each row sum of the nonnegative matrix $H_u$ as $1-2q-2q^2$, proving its absolute norm bound. For the lower bound translate $u$ to zero. Dilation gives $T_0(v,w)=\chi(v)T_0(1,w/v)$, so $H_0$ is multiplicative convolution. Its trivial-character eigenvalue is its positive row sum. For a nontrivial multiplicative character $\rho$, the eigenvalue is \[ -q+q^2+p^{-2}\sum_{\lambda\ne0,1}\rho(\lambda) \tr(\operatorname{Frob}_\lambda\mid\operatorname{Sym}^2\mathcal F), \] where $\mathcal F$ is the Legendre sheaf of \cref{thm:prelim:ks} with $h(X)=X(X-1)$. Indeed its determinant is $\overline{\Q}_\ell(-1)$, so the symmetric-square trace is the square of the cubic character sum minus $p$; the missing value at $1$ is $q^2$. The Kummer sheaf for $\rho$ is the corresponding eigensheaf of $z\mapsto z^{p-1}$ on $\mathbb G_m$. It has weight zero and is tame. The twist of $\operatorname{Sym}^2\mathcal F$ has rank $3$, weight $2$, and is tame at $0,1,\infty$. Its geometric irreducibility follows from the $\mathrm{SL}_2$ monodromy of $\mathcal F$ and irreducibility of the symmetric square. Thus its invariants and coinvariants vanish. By \cref{thm:prelim:curves,thm:prelim:gos}, $H_c^0=H_c^2=0$ and $\dim H_c^1=3$. The trace formula and Deligne's bound (\cref{thm:prelim:lefschetz,thm:prelim:weights}) bound the sum by $3p^{3/2}$. All eigenvalues are real because $H_0$ is symmetric. This proves the stated lower bound. \end{proof} \begin{theorem}[The centred accepting rectangle]\label{thm:rectangle-gram} For $p\equiv3\pmod4$, $p\ge2^{20}$, let $Z_4=(1-q)(1-3q)(1-7q)$. Then \begin{equation}\label{eq:rectangle-gram-cap} \|\mathsf R_\circ\|\le 4q\sqrt{\frac{920+4012r+48641q+3008q^2+320q^3}{(1-q)Z_4}} \le121.588q. \end{equation} For $p\ge2^{36}$ the last bound improves to $121.328q$. Without \cref{lem:rectangle-mellin}, the same argument gives $128q$. These are centred bounds; they do not replace a raw nonstar or collision bound elsewhere in the proof. \end{theorem} \begin{proof} Put $h=1-q$ for this proof. Initially give the four core coordinates independent uniform laws and retain the uniform distinct private pair. With $s=(-1,-1,1,1)$, set \[ k_x(t)=\prod_{i=1}^4(1+s_i\chi(t-x_i)),\qquad N(x;b_0,b_1)=(k_x(b_0)-1)(k_x(b_1)-1) -\sum_i\chi(b_0-x_i)\chi(b_1-x_i). \] This is exactly the sum of the nonstar terms. The accepting-core event has probability $Z_4/16$: each distinct ordered $c$-pair has $(p-3)/4$ common predecessors, from which the ordered $a$-pair is chosen distinctly. Restriction therefore costs $4/\sqrt{Z_4}$; output centring is a contraction. We bound $NP_0$ on the full core cube. \emph{The Gram away from private overlaps.} For four distinct private labels $z_1,z_2,z_3,z_4$, write \[ v=\E_y\prod_i\chi(z_i-y),\qquad t_i=\E_y\prod_{j\ne i}\chi(z_j-y),\qquad T=\sum_i t_i. \] Independent integration in the four core variables gives \begin{align} G={}&[(1-6q+v)^2-T^2]^2 -\sum_i[(1-3q)^2-t_i^2]^2+6h^4-3\notag\\ &-8[h^3(v-q)+q]+4v+12q^2.\label{eq:rectangle-gram-polynomial} \end{align} Denote the same polynomial on all private pair pairs by $\widetilde G$. With $a=1-6q$, $b=1-3q$, its nonconstant part is \begin{align*} \alpha v+6a^2v^2+(12q-54q^2)\sum_i t_i^2 -4a^2\sum_{i0$. Exact evaluation at $(q,r)=(2^{-20},2^{-10})$ and $(2^{-36},2^{-18})$ gives respectively coefficients less than $121.588$ and $121.328$. The elementary overlap bound gives instead \[ \|NP_0\|^2\le q^2\left(516+ \frac{500+3724r+48641q+96q^2}{h}\right), \] which proves the stated $128q$ alternative on the same domain. \end{proof} The coefficient in \eqref{eq:rectangle-gram-cap} may be used as $N_A/q$ in the gap estimate below. The selected completion weights and their certificates retain the larger, previously certified rectangle prices. They remain valid upper assignments; no global saving is claimed merely by reducing this local norm bound. \space % End sections/20a_rectangle_gram \begin{proposition}[Sharper bound for the centred rectangle, using the gap $30q-\ell_g^2$]\label{prop:l20-pair-gap} In the setting of \cref{prop:l20-rectangular} put \begin{gather*} g_{\mathbf v}=\frac{1-2q}{1-q},\qquad M_g=15+44\mathfrak m_++(42+12\eta)\eta^2,\qquad \tau_g^2=\frac{2qM_g}{(1-q)^2(1-2q)},\\ e_g=\frac{\sqrt{30}\,r(\eta+15q)\sqrt{g_{\mathbf z}}}{(1-q)\sqrt{g_{\mathbf v}}},\qquad w_g=\frac{\sqrt{30}\,r\rho_{\mathbf z\mathbf w}}{\sqrt{g_{\mathbf v}}}+e_g,\qquad l_g=2r+N_A,\\ x_g=2rw_g+\tau_gN_A,\qquad\Delta_g=30q-l_g^2 . \end{gather*} If $\Delta_g>0$, then $\norm{\mathsf R_c}\le c_{\rm gap}:=\bigl(\tau_g^2+x_g^2/\Delta_g\bigr)^{1/2}$. \end{proposition} \begin{proof} On $\mathcal H$, $\mathbf v^*\mathbf v=g_{\mathbf v}I$, so $\mathbf v'=\mathbf v/\sqrt{g_{\mathbf v}}$ is an isometry into the mean-zero functions of the pair. As $\E_z\ell(z,C)h(z)=-2r(\mathbf u\Phat h)(C)$ (proof of \cref{prop:l20-rectangular}(b)), $\mathbf zh=\E_z\mathsf K(z,C)h(z)/(\sqrt{15}\,r)$ for $h\in\mathcal H$. Given $b_0=y$, the label $b_1$ is uniform on the other $p-1$ labels and $\sum_{y'\ne y}\mathsf K(y',C)=p\bar{\mathsf K}-\mathsf K(y,C)$; with $\mathsf K^2=16\mathsf K$ this gives the exact action \[ \mathsf R\mathbf v=\sqrt{30}\,r\,\frac{\bar{\mathsf K}-16q}{1-q}\,\mathbf z . \] The Gram $(\mathsf R\mathbf v')^*\mathsf R\mathbf v'$ is self-adjoint and commutes with the square-affine maps, so it is a scalar (\cref{lem:spec:affpair}(d)); its trace is $30q\,\E[(\bar{\mathsf K}-16q)^2(1-q)^{-2}\norm{P_0\mathsf K(\cdot,C)}^2] /(15q\,g_{\mathbf v})$ with $\norm{P_0\mathsf K(\cdot,C)}^2=16\bar{\mathsf K}-\bar{\mathsf K}^2$, and division by $p-1$ gives \[ (\mathsf R\mathbf v')^*\mathsf R\mathbf v' =\frac{2q\,\E\bigl[(\bar{\mathsf K}-16q)^2(16\bar{\mathsf K}-\bar{\mathsf K}^2)\bigr]} {(1-q)^2(1-2q)}I . \] Here $\bar{\mathsf K}=16n/p=16nq$, where $n=\#\{z:\mathsf K(z,C)=16\}$; the weight vanishes at $n=0$, and for $n\ge1$, $0\le\bar{\mathsf K}-16q\le\bar{\mathsf K}\le16$, so the expectation is at most $\E(16\bar{\mathsf K}^3-\bar{\mathsf K}^4)$; expanding at $\bar{\mathsf K}=1+y$, $16\bar{\mathsf K}^3-\bar{\mathsf K}^4=15+44y+42y^2+12y^3-y^4$, and $|y|\le\eta$, $\E y\le\mathfrak m_+$ bound it by $M_g$. Thus $\norm{\mathsf R\mathbf v'}\le\tau_g$, and $\tau_g^2\ge30q$ as $M_g\ge15$. On the orthogonal complement of the range of $\mathbf v'$ in the mean-zero functions of the pair, $\mathbf v^*=0$, so there $\mathsf R_c=2r\mathbf w\mathbf e^*+\mathsf R_\circ$ has norm at most $l_g$, as $\norm{\mathbf w},\norm{\mathbf e}\le1$. Moreover $|(\bar{\mathsf K}-16q)/(1-q)-1|\le(\eta+15q)/(1-q)$ gives $\norm{\mathsf R\mathbf v'-\sqrt{30}\,r\mathbf z/\sqrt{g_{\mathbf v}}}\le e_g$ and $\norm{(\mathsf R\mathbf v')^*\mathbf w}\le w_g$, so the off-diagonal block of $\mathsf R_c^*\mathsf R_c$ in this decomposition has norm at most $2rw_g+\tau_gN_A=x_g$. The diagonal blocks have norms at most $\tau_g^2$ and $l_g^2$, and $\tau_g^2-l_g^2\ge\Delta_g>0$, so the largest eigenvalue of the scalar comparison matrix, and with it $\norm{\mathsf R_c}^2$, is at most $\tau_g^2+x_g^2/\Delta_g$. \end{proof} The nonstar term $N_A$ enters $c_{\rm gap}^2$ through $x_g$, of order $qr$, across the gap $\Delta_g$ of order $q$, and through $l_g$ in the gap itself, at relative order $r$; so it changes $(c_{\rm gap}/r)^2$ by $O(q)$, whereas in $k_4r+N_A$ it enters $c/r$ linearly, at order $r$. \begin{proposition}[Collisions with the core--pair weights of the proof; the caps of L20] \label{prop:l20-collisions} For $p\equiv3\pmod4$, $p\ge2^{20}$, put $E_{c,j}=e_j(p,12) =((j/2-1)2^j+1)r+12\cdot2^jq$ ($j=2,3,4$), $\Lambda_c=(1-e_2(p,6))^4(1-e_0(p,6))^2=(1-r-24q)^4(1-6q)^2$, $U_c=(1+E_{c,4})^6$, \begin{gather*} P_c(q)=96q+3712q^2+81920q^3+1245184q^4+12582912q^5+67108864q^6,\\ S_c=32q(1+E_{c,3})^2(1+E_{c,4})^3+64q(1+E_{c,2})(1+E_{c,3})^2(1+E_{c,4})^2,\\ D_{\rm bal}=\frac{S_c+U_c(P_c-96q)}{\Lambda_c}. \end{gather*} \begin{enumerate}[label=\textup{(\alph*)}] \item $\norm{T_{\rm coll}}\le D_{\rm bal}$ for the soft L20 kernel. \item Put $\eps_Z=N_{\rm ns}+D_{\rm bal}+m_\star$, $C_{20}=(s_pc_{\rm gap}/h_p+D_{\rm bal})/(1-\eps_Z)$, $H_{20}=(N_{\rm ns}+D_{\rm bal})/(1-\eps_Z)$, $g_{20}=C_{20}/r$ and $c^+_{20}=p\chi^+_p/(1-H_{20})$. If $\eps_Z<1/2$, $\Delta_g>0$, $c_{\rm gap}<1$, $C_{20}<1$ and $H_{20}<1$ at an endpoint $P\ge2^{20}$ (that is, with $q=1/P$ and $r=P^{-1/2}$), then $-g_{20}(P)p^{-1/2}\le\mathsf A_p\le1+c^+_{20}(P)/p$ for every prime $p\ge P$ with $p\equiv3\pmod4$, and a middle block $\Blk$ of a piece starting at $X\ge P$, with least prime $b$, has \[ \mathsf A_{\Blk}\succeq-g_{20}(P)\exp\bigl(c^+_{20}(P)L_{\rm loc}/(X\log X)\bigr) \,b^{-1/2}. \] \end{enumerate} \end{proposition} \begin{proof} (a) The soft kernel contains the factors $\mathsf K(b'_l,C)$ and $\mathsf K(b_l,C')$ (\cref{prop:l20-rectangular}(c)), which vanish at the core labels (\cref{lem:l20-star-matrix}(c)). So the strata of $T_{\rm coll}$ with a coincidence between a pair label of one half and a core label of the other contribute nothing, and in the bounds of \cref{cor:incident-weights} the weights $\alpha_{ij}(x)$ of the $16$ pairs $(i,j)$ joining a core coordinate and a pair coordinate may be replaced by zero: a stratum containing such a pair is bounded by zero, and the bounds of the other strata do not change. The remaining coincidences $x'_i=x_j$ join two core coordinates ($16$ choices of $(i,j)$) or two pair coordinates ($4$ choices); for these, $j\notin N(i)$ and $\mathrm{mg}(j,i)=0$ in \cref{lem:oct24-collision}. Fix $x$ and apply \cref{cor:incident-weights} with the actual incident weights $\alpha_{ij}(x)=w_i(x_j)$, where $w_i$ is the cross factor at vertex $i$ of that corollary. For an $a$-coordinate $i$ of $x'$ and a core coordinate $j$, $w_i(x_j)=\prod_{l=0,1}(1-\chi(b_l-x_j))$; for a $c$-coordinate, $w_i(x_j)=\prod_{l=0,1}(1+\chi(b_l-x_j))$; for a pair coordinate $i$ and a pair coordinate $j$, $w_i(x_j)=\mathsf K(x_j,C)$. At a core label $y$ of $x$ the labels $y,b_0,b_1$ are distinct, so the two products are $0$ or $4$, and not both are $4$. Let $n_-$ and $n_+$ count the core labels of $x$ at which the first, respectively the second, product is $4$; then $n_-+n_+\le4$, and the row charges $\rho_i(x)=q\sum_j\alpha_{ij}(x)$ are $\rho_a=4n_-q$ for the two $a$-coordinates, $\rho_c=4n_+q$ for the two $c$-coordinates and $\rho_{b_l}=q(\mathsf K(b_0,C)+\mathsf K(b_1,C))\le32q$ for the two pair coordinates. \emph{One coincidence.} Order the other vertices so that, for a coincident core coordinate, its two neighbours on the opposite side of the core come before the other coordinate on its side, and, for a coincident pair coordinate, the core alternates between the sides. The five remaining vertices then have $t^{ij}_\ell$ equal to $3,3,4,4,4$, respectively $2,3,3,4,4$, and \cref{cor:incident-weights} bounds the row sum of $T_{\rm coll,1}$ by $\Lambda_c^{-1}$ times \[ \sum_{i\ \rm core}\rho_i(x)(1+E_{c,3})^2(1+E_{c,4})^3 +\sum_{i\ \rm pair}\rho_i(x)(1+E_{c,2})(1+E_{c,3})^2(1+E_{c,4})^2\le S_c, \] since the core charges add up to $8(n_-+n_+)q\le32q$ and the pair charges to at most $64q$; here $\Lambda_c=L_{\rm int}$ and $e_t(p,2n)=E_{c,t}$. \emph{Two or more coincidences.} Every vertex has degree $d_i=4$, so $\Upsilon_k\le(1+E_{c,4})^6=U_c$, and the row sum of $T_{\rm coll,\ge2}$ is at most $U_c\Lambda_c^{-1}$ times the part of degree at least two of $\sum_I2^{e(I)}\prod_{i\in I}\rho_i(x)$. The internal edges join the $a$-coordinates to the $c$-coordinates, so this sum is $F(\rho_a,\rho_c)(1+\rho_{b_0})(1+\rho_{b_1})$ with \begin{align*} F(\rho_a,\rho_c)&=\sum_{k,l=0}^2\tbinom2k\tbinom2l2^{kl}\rho_a^k\rho_c^l\\ &=1+2(\rho_a+\rho_c)+(\rho_a+\rho_c)^2+6\rho_a\rho_c +8(\rho_a+\rho_c)\rho_a\rho_c+16\rho_a^2\rho_c^2 . \end{align*} As a polynomial in $\rho_a+\rho_c$, $\rho_a\rho_c$, $\rho_{b_0}$, $\rho_{b_1}$ its part of degree at least two has nonnegative coefficients, and $\rho_a+\rho_c\le16q$, $\rho_a\rho_c\le(\rho_a+\rho_c)^2/4$, $\rho_{b_l}\le32q$; so it is at most its value at $\rho_a=\rho_c=8q$, $\rho_{b_l}=32q$, which is $(1+32q)^2F(8q,8q)-1-96q=P_c-96q$. All these bounds are pointwise in $x$, and \cref{cor:incident-weights} turns them into the norm bound $\norm{T_{\rm coll}}\le D_{\rm bal}$. (b) \emph{Endpoint monotonicity.} Write every quantity as a function of $r=p^{-1/2}$, with $q=r^2$, on $(0,P^{-1/2}]$. The functions $N_{\rm ns}/q$ and $N_A/q$ are admissible in the sense of \cref{lem:majorant} (\cref{cor:extraction-compressed,cor:extraction-leaf}), and so is $D_{\rm bal}/q$: its numerator divided by $q$ is a polynomial with nonnegative coefficients in $r$ and the count errors, and $\Lambda_c$ is a product of factors $1-\varphi$ with admissible $\varphi<1$. The functions $m_\star/q$, $\mathfrak m_+/q$ and $\chi^+_p/q$ are nondecreasing: written in $r$, the numerator of $m_\star/q$ is nondecreasing on $(0,1]$ and its denominator $Z_4$ is positive and nonincreasing, and $\chi^+_p/q=(D_{\rm full}/r)^2/L_{\rm low}^2$ with $L_{\rm low}$ positive and nonincreasing (\cref{lem:record:root-marginal}(iii)) and $D_{\rm full}/r$ nondecreasing, since each term of $D_{\rm full}$ carries one of the factors $\Delta_2$, $q$, $\mathfrak a_p$, and $\Delta_2/r$, $q/r$ and $\mathfrak a_p/r$ are nondecreasing. The quantities $g_{\mathbf z}$, $1/g_{\mathbf v}=1+q/(1-2q)$, $1/h_p=(1+3q/(1-4q))/(1-5q)$, $\rho/q$, $\eta/r$, $s_p$ and $k_4$ are built from these by sums, products, square roots and quotients by positive nonincreasing denominators. Hence $\eps_Z$, $H_{20}$, $\tau_g/r$, $w_g/q$, $x_g/q=2r\,w_g/q+r(\tau_g/r)(N_A/q)$ and $c^+_{20}=(\chi^+_p/q)/(1-H_{20})$ are nondecreasing in $r$ while $\eps_Z$ and $H_{20}$ are below one; $\Delta_g/q=30-(l_g/r)^2$, with $l_g/r=2+r\,N_A/q$, is nonincreasing; and where $\Delta_g>0$ the functions $(c_{\rm gap}/r)^2=(\tau_g/r)^2+(x_g/q)^2/(\Delta_g/q)$ and $C_{20}/r=(s_p(c_{\rm gap}/r)/h_p+D_{\rm bal}/r)/(1-\eps_Z)$ are nondecreasing. If the gates hold at $P$, they therefore hold at every prime $p\ge P$, with $g_{20}(p)\le g_{20}(P)$ and $c^+_{20}(p)\le c^+_{20}(P)$. \emph{The caps.} At such a prime, \cref{prop:l20-pair-gap} gives $\norm{\mathsf R_c}\le c_{\rm gap}<1$, \cref{prop:l20-rectangular}(d) with $c_{\rm R}=c_{\rm gap}$ and $D_{\rm col}=D_{\rm bal}$ from (a) gives $T\succeq-C_{20}I$ and $\norm{T|_{\mathcal I^\perp}}\le C_{20}$, and \cref{prop:l20-completion} with $C_\perp=C_{20}$ gives $-g_{20}(p)rI\preceq\mathsf A_p\preceq(1+c^+_{20}(p)/p)I$. The block bound follows from \cref{lem:spec:tensorcomp}(b) with $g=g_{20}(P)$ and $c^+=c^+_{20}(P)$, where $g_{20}(P)p^{-1/2}\le C_{20}(P)<1$, and from $\sum_{p\in\Blk}1/p\le L/(X\log X)\le L_{\rm loc}/(X\log X)$ (\cref{lem:record:local-domain}(ii)). \end{proof} At the endpoint $p=Q_3$ (just below the middle primes) the main terms of $C_{20}/r$ are $s_pc_{\rm gap}/(h_pr)=5.47787\ldots$, against their limit $\sqrt{30}=5.47723\ldots$ as $p\to\infty$, and $D_{\rm bal}/r=0.02176\ldots$ ($D_{\rm bal}/q=97.18\ldots$, close to its leading coefficient $96$); the normalizer $h_p^{-1}$ adds about $4.01\cdot10^{-7}$ as a relative correction. So the collision bound $D_{\rm bal}$ is the largest correction, and $g_{20}-\sqrt{30}$ is asymptotic to $96r$ as $p\to\infty$. The other inputs at $Q_3$ are $N_{\rm ns}=7.336\cdot10^{-5}$ up to the displayed digits, $N_A/q=281.37$, $k_4=5.4772264$, $c_{\rm gap}=1.226351\cdot10^{-3}$, $\chi^+_p=1.0341\cdot10^{-6}$ and $H_{20}=7.8240\cdot10^{-5}$. \begin{certificate}[The L20 grid]\label{cert:l20-grid} At each of the $45$ endpoints below, the quantities $N_{\rm ns}$, $N_A$, $D_{\rm bal}$, $m_\star$, $\eps_Z$, $k_4$, $s_P$, $h_P$, $c_{\rm gap}$, $C_{20}$, $H_{20}$ and $\chi^+_P$ of the L20 estimates satisfy $\eps_Z<1/2$, $\Delta_g>0$, $c_{\rm gap}<1$, $C_{20}<1$ and $H_{20}<1$ in outward rational interval arithmetic, with the recorded values of $g_{20}$ and $c^+_{20}$ stated below. The scripts and records are in the directory \path{research/advance_2026_10_24/local/}. The record \path{l20_refined_Q_grid.json}, built by \path{l20_collision_balanced.py} on the rank-four, rectangular and gap evaluators \path{l20_rank4.py}, \path{l20_rectangular.py} and \path{l20_rectangular_gap.py} (and on the star matrix and the frame cap of \path{l20_full_star.py}, which asserts the characteristic polynomial of \cref{lem:l20-star-matrix}(a) in exact symbolic arithmetic), contains $45$ endpoints from $2^{20}$ to $2^{50}$, among them the $33$ piece starts. The nonstar ledger of $N_A$ (\cref{prop:l20-rectangular}(b)) is the histogram \path{middle_factor_probe/rectangular_A.hist.json.gz} of the same directory. At each endpoint $P$ it evaluates in outward rational interval arithmetic $N_{\rm ns}$, $N_A$, $D_{\rm bal}$, $m_\star$, $\eps_Z$, $k_4$, $s_P$, $h_P$, $c_{\rm gap}$, $C_{20}$, $H_{20}$ and $\chi^+_P$, checks $\eps_Z<1/2$, $\Delta_g>0$, $c_{\rm gap}<1$, $C_{20}<1$ and $H_{20}<1$, and records $g_{20}(P)$, rounded up to $10^{-12}$, and $c^+_{20}(P)$. At $Q_3$ it gives $g_{20}=5.500057067029$ and $c^+_{20}<20.633953751661$, hence a block cap below $5.500255036718$ at $L_{\rm loc}$; at $2^{20}$, $g_{20}=5.597878403332$; the limit is $\sqrt{30}$. These are the inherited uniform-root prices, preserved as a baseline in \cref{tab:data:l20-grid}. The selected native reconstruction recomputes the protected collision price of \cref{imp:local:collision-gap} at all 33 piece starts, with the same positive coefficient and marginal data. It then replaces L20 and L21 on the seven middle pieces from $2^{30}$ by the prices of \cref{cert:positive-root-caps}. The reference uses the selected value at $Q_3$, $g_{20}=5.481634403216$, proved through \cref{imp:local:collision-gap}; the larger value $5.500057067029$ recorded above is the weaker bound of \cref{prop:l20-collisions}, retained only as a comparison. At $Q_3$ the selected uniform root also has $c^+_{20}=20.633953751661$ and block cap below $5.481831709798$ at budget $585$. The exact selected spectra and weights are in \path{research/push_2026_10_25/global/refined_L570_source.json}; \path{research/improvements_2026_10_25/verify.py} independently checks the collision, endpoint and native-completion interfaces, and \path{research/push_2026_10_25/verify.py} authenticates their unchanged identity after scalar reanchoring. \end{certificate} \paragraph{Consequences and what to read next.} \Cref{thm:bmor} (the cell charges above $X_{\rm Ch}$); \cref{lem:paley-triple} (class-three counts); \cref{lem:record:fold-identification}, \cref{def:graphs:labeling} and \cref{def:spec:data} (the twelve-label graphs and their cuts); \cref{thm:spectral-criterion} and \cref{cor:spectral-criterion-blocks}, with the inputs of \cref{cor:extraction-compressed,lem:oct24-collision} (the route-A caps); \cref{lem:majorant} (evaluation at the piece start and at the endpoints); \cref{lem:spec:expansion,lem:spec:stars}, \cref{lem:general-star}, \cref{cor:star-matrix}, \cref{lem:spec:affpair}(d), \cref{lem:l20-star-mean} and \cref{lem:record:weighted-moment}, \cref{lem:swapped-rectangle}, \cref{prop:matching:positive}(a$''$), \cref{thm:weil}, \eqref{eq:two-root}, \cref{cor:soft-kernels}(a), \cref{cor:extraction-leaf}, \cref{cor:incident-weights} and \cref{lem:record:root-marginal}(ii),(iii) (the cap of L20); \cref{lem:spec:cutkernel} and \cref{lem:spec:tensorcomp}(b) (block caps); \cref{lem:record:repricing} and \cref{def:closing-quantities} (prices and the selection factor at $a$). Certificates: \cref{cert:record:middle-price,cert:layer12-grid,cert:l20-grid}. \paragraph{Hypotheses verified in this section (\cref{tab:hypotheses}).} the inputs of the rows ``(CP1) middle'' and ``$P$, $V$, $D$, $U_0$, tags'' that do not depend on the reference: the middle partition and its charges (\cref{def:record:exact-blocks,lem:record:block-charge,lem:record:lower-start-sums}, \cref{cert:record:middle-price}) and the caps of the twelve-label cuts L21, E21 and L10 and of the cut L20 of the uniform root (\cref{lem:layer12-caps,prop:l20-collisions}; \cref{cert:layer12-grid,cert:l20-grid}); and the piece caps of the restorations (\cref{lem:piece-caps}), an input of the row ``(CP5) variance classes''. The first two rows are completed in \cref{sec:middle-frame}. \space % End sections/20_middle_reference % Begin sections/20b_positive_roots \section{Middle primes II: reweighting the principal law on seven intervals} \label{sec:positive-roots} \paragraph{What this section proves and how to read it.} On seven middle intervals from $2^{30}$ onward, the uniform twelve-label law has spectral bound $g\to\sqrt{30}$, which forces completion weights too large for $\Theta<1$. This section reweights it by an explicit nonnegative function (a \emph{tilted law}, called a \emph{positive root} in the text) that preserves support and one-slot marginals and improves the bound to $g(\lambda)<\sqrt{30}$ (where $\lambda=2\ulaw/(1+\ulaw^2)$ in terms of the tilt parameter $\ulaw$ of \cref{def:positive-root}, and $g(\lambda)$ is the leading coefficient defined there), at the price of a larger bound at a second cut and a changed one-half marginal, both bounded here. The other $26$ intervals use the uniform law of \cref{sec:middle-reference}; the choice of which intervals are reweighted is part of the construction (\cref{sec:design}). Inputs: \cref{sec:middle-reference} and Part~IV trace estimates. Outputs: the two cut bounds and marginal controls used in \cref{sec:middle-frame}. A first reading should follow the definition and the two bound statements; the pair-score calculations are reference material. On seven pieces of the middle range, from $2^{30}$ onward, the two-layer root is a positive reweighting of the uniform twelve-label law. Six pieces use individual squares of the three quartic pair scores; the last uses 39 coherent traces, with a positive floor. The support, invariance under the chamber reflections and layer swap of \cref{lem:layer12-geometry}(a) and uniform one-slot marginals are preserved. We bound the chamber and layer operators in the fixed uniform induced-half charts used by \cref{sec:middle-frame}, and give the actual marginal variance and range needed by \cref{lem:record:root-marginal}(iv). The pair-score toolkit is proved first; then come the sharper collision bound on the two protected subspaces, the interpolation between the pair bounds for the actual (physical) kernel (\cref{imp:env:physical-interpolation}), the layer remainder summed without expanding all monomials (\cref{imp:env:layer-resummation}), and the finite bounds for the coherent law. The seven endpoint caps $g,c^+$ are in \cref{cert:positive-root-caps}. These caps determine the completion weights $w_{\rm D}$ and $v_{\rm L}$. The reason for the tilt is visible in the leading matrices. The negative cap of L20 of the uniform root tends to $\sqrt{30}$, the norm of the complete star matrix of its soft kernel (\cref{lem:l20-star-matrix}), and through the completion inequality $w_{\rm D}\ge d$ of \cref{lem:front12:reference}(iii), where $d$ is the block cap of L20, this cap fixes the first-order weights $w_{\rm D}=w_{\rm S}$ of the reference. The linear part $2\ulaw\Hbar$ of a tilt adds to that matrix a coupling of the pairs of opposite base labels, and the eigenvector of the least eigenvalue has a component along this coupling; the least eigenvalue rises to $-g(\lambda)$ with $g(\lambda)<\sqrt{30}$ (\cref{lem:root-pair-matrix}). This gain is at order one in the coefficient of $r$. The costs are of order $r$: the layer cut of the tilted root has a larger cap, which enters the reference only through the larger one-layer weight $v_{\rm L}$ it forces (\cref{rem:middle-weights}), and the half marginal of the root changes, which the restorations pay through its range ratio and its chi-square. \emph{Conventions.} Those of \cref{sec:middle-reference}. Throughout $p\equiv3\pmod4$, $q=1/p$, $r=p^{-1/2}$, every space carries a probability measure, $\ulaw\ge0$ is rational, and $P_0$ is the projection onto mean-zero functions. In \cref{imp:local:collision-gap} the same centering $P_0$ is written $Q$, with protected subspaces $P_{\rm c},P_{\rm p}$ defined there. For an operator $T$ with a kernel on a product of two spaces and a function $f$ on that product, $T\circ f$ is the operator whose kernel is the pointwise product of the kernel of $T$ with $f$, as in \cref{lem:swapped-rectangle,lem:tilt-marginals}. \subsection{The tilted law \texorpdfstring{$\Gamma_{p,\ulaw}$}{Gamma\_(p,u)}}\label{subsec:positive-root-law} On seven middle intervals the uniform twelve-label law is reweighted (tilted) by an explicit sum of squares, hence by a nonnegative weight with the same support. This one-parameter family is the positive root; the definition fixes the weight and the parameter value used on each interval. \begin{definition}[Positive roots]\label{def:positive-root} Let $x$ be a labelling of the twelve vertices $(u,\ell)$ of $G_{\rm L,2}$ at the prime $p$. For $j\in\{0,1,2\}$ let \[ \Hs j(x)=r\sum_{z\in\Fp}\chi\Bigl(\prod_{u\in\{j,j+3\}}\ \prod_{\ell\in\{0,1\}} (z-x_{u,\ell})\Bigr) \] be the normalized trace score of the opposite base pair $\{j,j+3\}$, and $\Hbar=(\Hs0+\Hs1+\Hs2)/3$. For rational $\ulaw\ge0$ the \emph{individual-square positive root} is \begin{equation}\label{eq:positive-root} \Gamma_{p,\ulaw}=\frac{w_\ulaw}{\E w_\ulaw}\,\lambda_p(G_{\rm L,2}),\qquad w_\ulaw=\frac13\sum_{j=0}^2(1+\ulaw\Hs j)^2, \end{equation} the expectation being under $\lambda_p(G_{\rm L,2})=\Gamma_{p,0}$. Thus \[ w_\ulaw=1+2\ulaw\Hbar+\ulaw^2 V, \qquad V=\frac13\sum_j\Hs j^2. \] We put $\gamma=\ulaw^2$, $s=1+\gamma$ and $\lambda=2\ulaw/s$, the \emph{strength} of the tilt. On a block, $\Gamma_{\Blk,\ulaw}=\bigotimes_{p\in\Blk}\Gamma_{p,\ulaw}$. The selected construction uses individual squares on the six successive middle pieces starting at $2^{30},2^{31},2^{32},2^{34},2^{36},2^{40}$, with parameters $711/4096$, $1021/4096$, $1455/4096$, $833/1024$, $3851/4096$, $4049/4096$, respectively. On $[2^{45},P_3)$ it uses instead \[ \Gamma_{p,\ulaw}= \frac{1/100+(1+\ulaw H_{\mathcal D_{39}})^2} {\E[1/100+(1+\ulaw H_{\mathcal D_{39}})^2]} \,\lambda_p(G_{\rm L,2}),\qquad \ulaw=67/40, \] where $H_{\mathcal D_{39}}=\sum_{S\in\mathcal D_{39}}c_SH_S$ with coefficients $c_S\in\{\pm1/15\}$ and $H_S$ the trace function of the support $S$; the list $\mathcal D_{39}$ of $39$ subsets (``supports'') of the twelve label positions, with the signs $c_S$, is defined in \cref{imp:local:filtered-coherent}. All expectations normalising these weights are under the uniform law $\lambda_p(G_{\rm L,2})$. Below $2^{30}$ the principal law remains uniform. \end{definition} Why squares of the individual scores, rather than the square $(1+\ulaw\Hbar)^2$ of their average? The two weights have the same linear term $2\ulaw\Hbar$, but the square of the average also contains the mixed products $\Hs j\Hs k$ ($j\ne k$), whose cut operators are harder to bound; the individual-square weight avoids them. On the last interval such products are instead included in a controlled form: the score $H_{\mathcal D_{39}}$ is one symmetrised list of trace functions, invariant under all chamber reflections and the layer swap, so that the same tilted law can be bounded at every sorting cut. It is called the \emph{coherent} law for this reason, and the list of supports with their coefficients is called its \emph{dictionary}. The three base pairs are $\{0,3\}$, $\{1,4\}$ and $\{2,5\}$: each consists of a base of the even component $\{0,2,4\}$ of $G_{\rm L,2}$ and a base of the odd component $\{1,3,5\}$, and a score is a quartic character sum over the four labels of the pair, two in each layer. \begin{lemma}[Properties of the positive roots]\label{lem:positive-root-properties} Let $\Gamma_{p,\ulaw}$ be the individual-square root of \eqref{eq:positive-root}. The coherent root has the separate admissibility statement of \cref{lem:imp:coherent39-law}. \begin{enumerate}[label=(\alph*)] \item On the support of $\Gamma_{p,0}$ every score lies in $r\Z$ and satisfies $|\Hs j|\le2+r$, and $w_\ulaw>0$. Hence $\Gamma_{p,\ulaw}$ is a probability law with the support of $\Gamma_{p,0}$, and it accepts the six queries. \item The chamber reflections $u\mapsto k-u$ ($k\in\{1,3,5\}$) and the translation $u\mapsto u+2$ permute the three scores, and the layer swap $\ell\mapsto1-\ell$ and every map $z\mapsto\alpha z+\beta$ of the labels with $\alpha\ne0$ fix each of them. Hence $\Gamma_{p,\ulaw}$, and $\Gamma_{\Blk,\ulaw}$ on a block, is invariant under the maps of \cref{lem:layer12-geometry}(a) and under the square-affine maps, and every slot is uniform. \item At the chamber cut $\vartheta_0$, with plus half $(a,b,c)$ on the objects $0,1,2$ and reflected half $(a',b',c')$ on the objects $5,4,3$, the scores pair $a$ with $c'$, $b$ with $b'$ and $c$ with $a'$; the reflection exchanges $\Hs0$ and $\Hs2$ and fixes $\Hs1$. At the layer cut $\iota$ each score selects in each layer one label of each of the two components of $G_{\rm L,2}$, at the same bases. \end{enumerate} The half marginals of $\Gamma_{p,\ulaw}$ differ from the uniform induced half laws at order $r$, as quantified in \cref{prop:root-chamber,prop:root-layer}; all caps below are proved in those fixed uniform half charts, which are the diagonal measures of the completion. \end{lemma} \begin{proof} (a) On the support all twelve labels are distinct, so the four labels of a base pair are distinct. The sum in $\Hs j$ is an integer, and \cref{thm:weil}(b) with $t=4$ bounds its modulus by $2\sqrt p+1$; hence $\Hs j\in r\Z$ and $|\Hs j|\le2+r$. Let $\ulaw>0$. If $1+\ulaw\Hs j=0$ with $\Hs j=rn$, $n\in\Z$, then $\sqrt p=-\ulaw n$ would be rational; so every square in $w_\ulaw$ is strictly positive on the support (and $w_0=1$), $\E w_\ulaw>0$, and $\Gamma_{p,\ulaw}$ has the support of $\Gamma_{p,0}$. Acceptance of a query is a property of the support, and $\Gamma_{p,0}$ accepts the six queries. (b) $\Hs j$ depends only on the four labels on the vertices $(u,\ell)$ with $u\in\{j,j+3\}$, symmetrically. The map $u\mapsto k-u$ sends $\{j,j+3\}$ to $\{k-j,k-j+3\}$ and $u\mapsto u+2$ sends it to $\{j+2,j+5\}$ (indices mod $6$), both base pairs; the layer swap fixes the vertex set of each base pair. Under $z\mapsto\alpha z+\beta$ the substitution $z=\alpha z'+\beta$ in the defining sum multiplies the product by $\alpha^4$, and $\chi(\alpha^4)=1$. The weight $w_\ulaw$ is a symmetric function of $(\Hs0,\Hs1,\Hs2)$, so every map that preserves $\Gamma_{p,0}$ and permutes the scores preserves $w_\ulaw$ and $\Gamma_{p,\ulaw}$. The maps of \cref{lem:layer12-geometry}(a) are automorphisms of $G_{\rm L,2}$ and preserve its uniform labelling law, and so do the square-affine maps, which preserve strict squareness of differences; a block law is a product. Translations act transitively on the labels, so every slot is uniform (\cref{lem:marginals}). (c) At $\vartheta_0$ the reflection is $u\mapsto5-u$, so the objects $0,1,2$ of the plus half face $5,4,3$. The base pairs $\{0,3\}$, $\{1,4\}$, $\{2,5\}$ therefore join $a$ with $c'$, $b$ with $b'$ and $c$ with $a'$, and $u\mapsto5-u$ maps $\{0,3\}$ to $\{2,5\}$ and $\{1,4\}$ to itself. At $\iota$ the plus half is the layer $\ell=0$, and the base pair $\{j,j+3\}$ has one base in each component. \end{proof} \subsection{The chamber symmetry for the tilted law}\label{subsec:positive-root-chamber} This subsection proves the cap of the chamber cut L20 of a positive root. The proof follows that of \cref{subsec:middle-l20} for the uniform root: the soft kernel is a swapped rectangle, its leading part is a complete star matrix synthesized by the actual frame, and everything else is a remainder of order $q$. The tilt adds to the leading part one exact matrix term, the coupling of the pair features by the linear term $2\ulaw\Hbar$ (\cref{lem:root-pair-matrix}); its square terms are, up to order $q$, multiples of the untilted kernel (\cref{lem:root-square}); the linear term has an explicit remainder (\cref{lem:root-linear}); and the normalization, the half marginal and the pointwise conditional score mean are bounded in \cref{lem:root-normalization}. All estimates are written so that they can be evaluated at a prime endpoint and hold for every larger prime. \paragraph{The chart.} At $\vartheta_0$ the half graph of the root is $G_{\rm F,2}$ (\cref{lem:layer12-geometry}(b)), and the half reference is $\mu_p=\lambda_p(G_{\rm F,2})=\lambda_{F,p}$, the uniform law on injective tuples $x=(a_0,a_1,b_0,b_1,c_0,c_1)$ with $a_i\to c_j$. We use the notation of \cref{subsec:middle-l20}: the \emph{core} $C=(a_0,a_1,c_0,c_1)$ and the \emph{pair} $b=(b_0,b_1)$ of $x$; the independent laws $\mu^{\rm core}$ (the uniform law of the admissible cores, injective directed copies of $K_{2,2}$) and $\mu^{\rm pair}$ (the uniform law of the ordered distinct pairs) of \cref{prop:l20-rectangular}; and the features $V_k$, $W_S$, $\mathbf u,\mathbf v,\mathbf w,\mathbf z,\mathbf e$ of \cref{lem:l20-star-matrix}, the same formulas defining them on $\mu_p$ and on $\mu^{\rm core}\otimes\mu^{\rm pair}$. The law $\mu_p$ is $\mu^{\rm core}\otimes\mu^{\rm pair}$ conditioned on $b\cap C=\emptyset$, an event of probability \[ h_p=\frac{(1-4q)(1-5q)}{1-q}\ \ge\ h'_p=(1-4q)(1-5q), \] and $J_\mu\colon L^2(\mu_p)\to L^2(\mu^{\rm core}\otimes\mu^{\rm pair})$ denotes its isometric embedding (\cref{lem:restriction}(a)). The rectangle of \cref{prop:l20-rectangular} is built from $\mathsf K(z,C)$, $\bar{\mathsf K}(C)=\E_z\mathsf K(z,C)$, $\mathsf R(C;b)=\mathsf K(b_0,C)\mathsf K(b_1,C)$ and $\mathfrak r=\mathsf R\one$: \[ \mathsf R=\mathfrak r\otimes\one+\mathsf R_\star+\mathsf R_\circ,\qquad \mathsf R_\star=r\bigl(\sqrt{30}\,\mathbf z\mathbf v^*+2\mathbf w\mathbf e^*\bigr),\qquad \|\mathsf R_\circ\|\le N_A,\qquad\mathsf R_\circ\one=\mathsf R_\circ^*\one=0 \] \eqref{eq:l20-rectangle}, with $\|\mathbf z\|^2\le g_{\mathbf z}$, $\|\mathbf w\|,\|\mathbf v\|,\|\mathbf e\|\le1$ (\cref{prop:l20-rank4}) and $\|\mathsf R_\star\|\le k_4r$ (\cref{prop:l20-rectangular}(b)), and $\mathsf R^*\one=\E\mathfrak r$ is constant. The soft L20 kernel on $L^2(\mu^{\rm core}\otimes\mu^{\rm pair})$ is $K_{\rm soft}=T[\mathsf R,\mathsf R]=(\mathsf R\otimes\mathsf R^*)\operatorname{Swap}$ \eqref{eq:l20-swap}, with kernel $\mathsf R(C;b')\mathsf R(C';b)$ at a pair of halves $x=(C,b)$, $x'=(C',b')$. Further \begin{gather*} Z_4=(1-q)(1-3q)(1-7q),\qquad\eta=11r+2q,\qquad c_0=\frac4{1-q}+2q,\\ \mathfrak r_+=\frac{(1+\eta)^2}{1-q},\qquad\mathfrak r_-=(1-\eta)(1-\eta-16q), \end{gather*} so that $\mathfrak r_-\le\mathfrak r\le\mathfrak r_+$, as $|\bar{\mathsf K}-1|\le\eta$ (\cref{prop:l20-rectangular}(d)). We write $\mathfrak r_2=s_p\ge\|\mathfrak r\|_2$ for the bound of \cref{prop:l20-rectangular}(d), $\mathfrak m_+\ge|\E\bar{\mathsf K}-1|$ for that of \cref{prop:l20-rank4}, $\Gamma_{20}\ge\|\mathcal F\|^2$ for the frame cap of \cref{lem:l20-star-matrix}(b) ($\mathcal F$ the synthesis of the eighteen features on $L^2(\mu_p)$, in the coefficient space of \cref{lem:l20-star-matrix}), $N_A$, $D_{\rm bal}$ and $\eps_Z$ for the caps and the normalizer error of \cref{prop:l20-rectangular,prop:l20-collisions}, $\chi^+_p\ge\|T_0\one-\one\|^2$ for the root-half chi-square bound of \cref{subsec:middle-l20} (\cref{lem:record:root-marginal}(ii)), and $R_p$ for that of \cref{lem:record:root-marginal}(i). For a feature map $Y$ on $\mu^{\rm core}\otimes\mu^{\rm pair}$ and the same map $Y_\mu$ on $\mu_p$, $J_\mu^*Y=\sqrt{h_p}\,Y_\mu$ (\cref{lem:restriction}(a)); hence a leading operator $YMY'^*$ of the soft kernel becomes $Y_\mu MY_\mu'^*$ under the compression $h_p^{-1}J_\mu^*(\cdot)J_\mu$, with no factor $h_p^{-1}$, which only norm remainders pay. The cut operator of the uniform root on $L^2(\mu_p)$ is the operator $T$ of \cref{subsec:middle-l20}, which we write $T_0$: \[ T_0=K_0/Z_0,\qquad K_0=K^\mu_{\rm soft}-T_{\rm coll},\qquad K^\mu_{\rm soft}=h_p^{-1}J_\mu^*K_{\rm soft}J_\mu , \] where $K^\mu_{\rm soft}$ is the soft kernel as an operator on $L^2(\mu_p)$, $T_{\rm coll}$ is its restriction to the pairs of halves with a common label, a nonnegative kernel with $\|T_{\rm coll}\|\le D_{\rm bal}$ (\cref{prop:l20-collisions}(a)), and $Z_0=\ip\one{K_0\one}\ge1-\eps_Z$ (\cref{prop:l20-completion,prop:l20-rectangular}); on cross-injective pairs every factor of the soft kernel is $0$ or $2$, so the \emph{raw kernel} $K_0$ is $2^{16}$ times the indicator that $(x,x')$ join to a labelling of $G_{\rm L,2}$. By \cref{lem:spec:cutkernel}(f) the cut operator of $\Gamma_{p,\ulaw}$ on $L^2(\mu_p)$ is \[ T_\ulaw=\frac{T_0\circ w_\ulaw}{\E_{\Gamma_{p,0}}w_\ulaw} =\frac{K_0\circ w_\ulaw}{\ip\one{(K_0\circ w_\ulaw)\one}}, \] self-adjoint because $w_\ulaw$ is invariant under the reflection (\cref{lem:positive-root-properties}(c)). \paragraph{The scores as kernels.} For a pair $y=(y_0,y_1)$ of labels put $\psi_y(z)=\chi(z-y_0)\chi(z-y_1)$. By \cref{lem:positive-root-properties}(c), at $\vartheta_0$ \[ \Hs0(x,x')=\frac1r\E_z\psi_a(z)\psi_{c'}(z),\qquad \Hs1(x,x')=\frac1r\E_z\psi_b(z)\psi_{b'}(z),\qquad \Hs2(x,x')=\frac1r\E_z\psi_c(z)\psi_{a'}(z), \] where $a,b,c$ are the pairs of $x$ and $a',b',c'$ those of $x'$; so the multiplier of a score is a scalar product of rows of raw pair maps, the setting of \cref{lem:swapped-rectangle}(d), and we call $\Hs0,\Hs2$ the \emph{core scores} and $\Hs1$ the \emph{private score}. Let $\mathcal U_a=W_{01}/r$ and $\mathcal U_c=W_{45}/r$ be the normalized pair features of the core and $\mathcal U_b=W_{23}/r=\mathbf e$ that of the private pair. Since $\E_z\psi_y(z)=-q$ for distinct labels, $W_{01}$ has the kernel $\psi_a(z)+q$ on mean-zero label functions, and \begin{equation}\label{eq:root-score-feature} \Hs0=r\,\mathcal U_a\mathcal U_c^*+qr,\qquad \Hs1=r\,\mathcal U_b\mathcal U_b^*+qr,\qquad \Hs2=r\,\mathcal U_c\mathcal U_a^*+qr \end{equation} as kernels on the half, the term $qr$ denoting the constant kernel $qr\,\one\otimes\one$. In the coefficient space of \cref{lem:l20-star-matrix} the three couplings are $e_{01}e_{45}^*$, $e_{23}e_{23}^*$ and $e_{45}e_{01}^*$. \begin{lemma}[The pair-feature matrix of a tilt]\label{lem:root-pair-matrix} In the coefficient space of \cref{lem:l20-star-matrix}, with orthonormal coordinates $e_i$ ($0\le i\le5$) and $e_S$ (the twelve supports) and $\Phat$ specialized to $i$ (\cref{rem:realified-gates}), let $M$ be the star matrix of the soft L20 kernel and, for $\lambda\ge0$, \[ M_\lambda=M+\tfrac\lambda3\bigl(e_{01}e_{45}^*+e_{45}e_{01}^*+e_{23}e_{23}^*\bigr). \] Then $M_\lambda$ is unitarily equivalent to the direct sum of $\left(\begin{smallmatrix}0&2&\sqrt{26}\\2&\lambda/3&0\\\sqrt{26}&0&0\end{smallmatrix}\right)$, $\left(\begin{smallmatrix}0&2\\2&\lambda/3\end{smallmatrix}\right)$, $(-\lambda/3)$ and the zero matrix of size twelve; its characteristic polynomial is $x^{12}(x+\frac\lambda3)(x^2-\frac\lambda3x-4)(x^3-\frac\lambda3x^2-30x+\frac{26\lambda}3)$. Consequently, for $0\le\lambda\le3\sqrt{26}$ the least eigenvalue of $M_\lambda$ is $-g(\lambda)$, where $g(\lambda)\in(\sqrt{26},\sqrt{30}]$ is the root of \begin{equation}\label{eq:root-cubic} 3g^3+\lambda g^2-90g-26\lambda=0 , \end{equation} decreasing in $\lambda$, $g(0)=\sqrt{30}$; every other negative eigenvalue is at least $-\max(2,\lambda/3)$; and $\|M_\lambda\|\le\sqrt{30}+\lambda/3$. The same holds at $\Phat=-i$. \end{lemma} \begin{proof} (1) As in the proof of \cref{lem:l20-star-matrix}(a) put $\hat{\mathbf v}=(e_2+e_3)/\sqrt2$, $\hat{\mathbf w}=(e_0+e_1+e_4+e_5)/2$, $\hat{\mathbf e}=e_{23}$, $\hat{\mathbf u}=(e_0+e_1-e_4-e_5)/2$ and \[ \hat{\mathbf z}=\frac1{\sqrt{15}}\Bigl(\sum_S\sigma_Se_S-2i\,\hat{\mathbf u}\Bigr),\qquad \sigma_S=(-1)^{|S\cap\{0,1\}|}, \] the sum running over the eleven supports $S\subseteq\{0,1,4,5\}$ of the core stars, and $\sigma_S$ being the sign of the star $S$ in the expansion of $\mathsf K$. The vectors $\hat{\mathbf v},\hat{\mathbf z},\hat{\mathbf w},\hat{\mathbf e}$ are orthonormal ($|\hat{\mathbf z}|^2=(11+4)/15$), and a comparison of entries gives \[ M=\sqrt{30}\,(\hat{\mathbf v}\hat{\mathbf z}^*+\hat{\mathbf z}\hat{\mathbf v}^*) +2(\hat{\mathbf w}\hat{\mathbf e}^*+\hat{\mathbf e}\hat{\mathbf w}^*). \] (2) $\sigma_{01}=\sigma_{45}=1$, so the coordinates of $\hat{\mathbf z}$ along $e_{01}$ and $e_{45}$ are both $1/\sqrt{15}$. With $\hat{\mathbf u}_\pm=(e_{01}\pm e_{45})/\sqrt2$ this gives \[ \hat{\mathbf z}=\sqrt{2/15}\;\hat{\mathbf u}_++\sqrt{13/15}\;\hat{\mathbf z}_\perp \] with a unit vector $\hat{\mathbf z}_\perp$ orthogonal to $\hat{\mathbf v}$, $\hat{\mathbf w}$, $\hat{\mathbf e}$, $\hat{\mathbf u}_+$ and $\hat{\mathbf u}_-$; the six vectors $\hat{\mathbf v},\hat{\mathbf u}_+,\hat{\mathbf z}_\perp,\hat{\mathbf w},\hat{\mathbf e}, \hat{\mathbf u}_-$ are orthonormal. (3) $e_{01}e_{45}^*+e_{45}e_{01}^*=\hat{\mathbf u}_+\hat{\mathbf u}_+^*-\hat{\mathbf u}_-\hat{\mathbf u}_-^*$, so the pair term is $\frac\lambda3(\hat{\mathbf u}_+\hat{\mathbf u}_+^*-\hat{\mathbf u}_-\hat{\mathbf u}_-^*+\hat{\mathbf e}\hat{\mathbf e}^*)$. (4) As $\sqrt{30}\sqrt{2/15}=2$ and $\sqrt{30}\sqrt{13/15}=\sqrt{26}$, \begin{multline*} M_\lambda=2(\hat{\mathbf v}\hat{\mathbf u}_+^*+\hat{\mathbf u}_+\hat{\mathbf v}^*) +\sqrt{26}\,(\hat{\mathbf v}\hat{\mathbf z}_\perp^*+\hat{\mathbf z}_\perp\hat{\mathbf v}^*) +\tfrac\lambda3\hat{\mathbf u}_+\hat{\mathbf u}_+^*\\ +2(\hat{\mathbf w}\hat{\mathbf e}^*+\hat{\mathbf e}\hat{\mathbf w}^*)+\tfrac\lambda3\hat{\mathbf e}\hat{\mathbf e}^* -\tfrac\lambda3\hat{\mathbf u}_-\hat{\mathbf u}_-^*. \end{multline*} In the orthonormal bases $(\hat{\mathbf v},\hat{\mathbf u}_+,\hat{\mathbf z}_\perp)$, $(\hat{\mathbf w},\hat{\mathbf e})$, $\hat{\mathbf u}_-$, completed by an orthonormal basis of the complement, on which $M_\lambda$ vanishes, this is the displayed direct sum. Its blocks have the characteristic polynomials $x^3-\frac\lambda3x^2-30x+\frac{26\lambda}3$, $x^2-\frac\lambda3x-4$ and $x+\frac\lambda3$. (5) For $g>0$ the value of the cubic at $x=-g$ is $-f(g)/3$ with $f(g)=3g^3+\lambda g^2-90g-26\lambda$. Since $f(0)=-26\lambda\le0$ and $f''\ge0$ on $[0,\infty)$, $f$ has exactly one positive root $g(\lambda)$ (for $\lambda=0$ it is $\sqrt{30}$); as $f(\sqrt{26})=-12\sqrt{26}<0$ and $f(\sqrt{30})=4\lambda\ge0$, it lies in $(\sqrt{26},\sqrt{30}]$. At the root $\partial_gf=9g^2+2\lambda g-90>0$ and $\partial_\lambda f=g^2-26>0$, so $g$ decreases in $\lambda$. So the $3\times3$ block has the single negative eigenvalue $-g(\lambda)$. The $2\times2$ block has the negative eigenvalue $\lambda/6-(\lambda^2/36+4)^{1/2}\in[-2,0)$, and the last block $-\lambda/3$; for $\lambda\le3\sqrt{26}<3g(\lambda)$ both lie above $-g(\lambda)$. The $3\times3$ block is $B_0+\frac\lambda3\hat{\mathbf u}_+\hat{\mathbf u}_+^*$, where $B_0$ has the characteristic polynomial $x^3-30x$, so its norm is at most $\sqrt{30}+\lambda/3$; the $2\times2$ block has norm $\lambda/6+(\lambda^2/36+4)^{1/2}\le2+\lambda/3$. At $\Phat=-i$ the matrix is the complex conjugate (\cref{rem:realified-gates}), with the same spectrum. \end{proof} The orientation of the pair term matters. The scores couple the core pair $a$ of one half with the core pair $c'$ of the other, and the leading vector $\hat{\mathbf z}$ has a component along $\hat{\mathbf u}_+$, on which this coupling is positive. With the opposite sign on the two core couplings, $\hat{\mathbf u}_+$ and $\hat{\mathbf u}_-$ exchange their roles, the cubic becomes $3g^3-\lambda g^2-90g+26\lambda=0$, and its root exceeds $\sqrt{30}$. \begin{lemma}[Square of a score on the rectangle]\label{lem:root-square} Suppose $k_4r+N_A<1$. Then for each score, on $L^2(\mu^{\rm core}\otimes\mu^{\rm pair})$, \[ \bigl\|K_{\rm soft}\circ\Hs j^2-(1-2q)^2\,K_{\rm soft}\bigr\|\le256c_0\mathfrak r_+q, \qquad \bigl\|K_{\rm soft}\circ\Hs j^2-K_{\rm soft}\bigr\|\le4q\mathfrak r_2^2+256c_0\mathfrak r_+q . \] \end{lemma} \begin{proof} Take the core score $\Hs0$; $\Hs2$ is its transpose. For a pair $y$ of distinct labels let $\Psi_y(z,z')=\psi_y(z)\psi_y(z')$ in $L^2(\Fp^2)$, so that $\Hs0^2(x,x')=q^{-1}\ip{\Psi_a}{\Psi_{c'}}$. By \cref{cor:raw-pair-maps}(b), $\Psi_y=r(1-2q)d+\rho_y$, where $d=\sqrt p\,\one_{z=z'}$ is a unit vector, $\rho_y\perp d$ is the row of the remainder of \eqref{eq:raw-pair-split}, and the map $F\mapsto\ip{\rho_y}F$ has norm at most $\sqrt{c_0}\,q$ into $L^2$ of a uniform distinct pair $y$. Under $\mu^{\rm core}$ the pairs $a$ and $c$ of a core are uniform distinct pairs, so the same bound holds into $L^2(\mu^{\rm core})$. Since $\rho\perp d$, the cross terms vanish and \[ \Hs0^2=(1-2q)^2+q^{-1}\ip{\rho_a}{\rho_{c'}},\qquad K_{\rm soft}\circ\Hs0^2-(1-2q)^2K_{\rm soft} =q^{-1}\,T[\mathsf R,\mathsf R]\circ\ip{\rho_a}{\rho_{c'}} . \] By \cref{lem:swapped-rectangle}(d) the right side is $q^{-1}(\mathcal Y_a\otimes I)\operatorname{Swap}(\mathcal Y_c^*\otimes I)$, the auxiliary label being shared and the private variables exchanged, where $\mathcal Y_a$ has the kernel $\mathsf R(C;b)\rho_{a(C)}$ from $L^2(\mu^{\rm pair})\otimes L^2(\Fp^2)$ to $L^2(\mu^{\rm core})$, and $\mathcal Y_c$ likewise. The Gram $\mathcal Y_a\mathcal Y_a^*$ is the pointwise product of the positive semidefinite kernel $\mathsf R\mathsf R^*$, whose diagonal is $\E_b\mathsf R(C;b)^2=256\,\mathfrak r(C)\le256\,\mathfrak r_+$ ($\mathsf R$ takes the values $0$ and $256$), with the Gram of the residual pair map, which lies between $0$ and $c_0q^2$. By the positive Schur order of \cref{lem:swapped-rectangle}(b), $\|\mathcal Y_a\|^2\le256c_0\mathfrak r_+q^2$, and likewise for $\mathcal Y_c$; this proves the first bound for the core scores. For the private score the pairs $b$ and $b'$ are the input variables of $\mathsf R$: in the variables $(b,C)$ the soft kernel is $T[\mathsf R^*,\mathsf R^*]$ (the last sentence of \cref{lem:swapped-rectangle}), and the same argument applies with the rows of $\mathsf R^*$, whose square norm is the constant $256\,\E\mathfrak r\le256\,\mathfrak r_+$. For the second bound, $\mathsf R=\mathfrak r\otimes\one+\mathsf R_c$ with $\mathsf R_c\one=0$ and $\mathsf R_c^*\mathfrak r=0$ (\cref{prop:l20-rectangular}(a)), so $\mathsf R$ maps $\one$ to $\mathfrak r$ and $\one^\perp$ into $\mathfrak r^\perp$, and its norm is the larger of $\|\mathfrak r\|_2\le\mathfrak r_2$ and $\|\mathsf R_c\|\le k_4r+N_A<1$ (\cref{prop:l20-rectangular}(b),(d)). As $\mathfrak r_2=s_p\ge1/(1-q)>1$, $\|K_{\rm soft}\|=\|\mathsf R\|^2\le\mathfrak r_2^2$ (\cref{lem:swapped-rectangle}(a)), and $1-(1-2q)^2\le4q$. \end{proof} The estimate bounds the square of a score on the whole rectangle at once, with the coefficient $4\mathfrak r_2^2+256c_0\mathfrak r_+$ of $q$, which tends to $1028$ as $p\to\infty$. Bounded class by class instead, the remainder class of the rectangle alone would give about $N_A^2/q$, about $8\cdot10^4q$. \paragraph{Linear prices.} The linear part of the tilt is $K_{\rm soft}\circ\Hbar$. Its finite price uses the following constants. Put \[ d_{\mathsf K}=\Bigl(\frac{5q+34qr+11q^3}{Z_4}\Bigr)^{1/2}+2q,\quad d_{\mathfrak r}=\frac{(2+\eta+16q)d_{\mathsf K}+15q}{1-q},\quad \delta_{\mathfrak r}=\frac{d_{\mathfrak r}}{\sqrt{1-q}},\quad A_{\mathfrak r}=1+\delta_{\mathfrak r}. \] In the expansion of $\bar{\mathsf K}-1$ the single terms vanish and the pair terms sum to exactly $2q$; the higher terms are $\mathcal W/p$ in the notation of \cref{lem:record:weighted-moment} (signs $(-1,-1,1,1)$ on $(a_0,a_1,c_0,c_1)$), and the core law $\mu^{\rm core}$ has the density $P_{\rm adm}D_4/Z_4$ relative to independent uniform labels ($D_4$ is the indicator that the four labels are distinct, and $P_{\rm adm}$ is $16$ on the admissible cores, of total probability $Z_4/16$, and $0$ on the other distinct quadruples), so $\E_{\mu^{\rm core}}(\mathcal W/p)^2\le\E[P_{\rm adm}\mathcal W^2]/(p^2Z_4)$. Hence \cref{lem:record:weighted-moment}(b) gives $\|\bar{\mathsf K}-1\|_2\le d_{\mathsf K}$, and since $(1-q)(\mathfrak r-1)=(\bar{\mathsf K}-1)(\bar{\mathsf K}+1-16q)-15q$, $\|\mathfrak r-1\|_2\le d_{\mathfrak r}$. For a core function $f$ invariant under the square-affine maps and a normalized core star $\mathcal U_S=W_S/r$, the Gram of $f\mathcal U_S$ commutes with the affine group and is self-adjoint, hence scalar (\cref{lem:spec:affpair}(d)), and its trace gives $\|f\mathcal U_S\|\le\|f\|_2/\sqrt{1-q}$ (as in \cref{lem:general-star}(a)). So multiplying a core star by $\mathfrak r$ changes it by at most $\delta_{\mathfrak r}$ and enlarges its norm by at most the factor $A_{\mathfrak r}$; for the private features, which are independent of the core, the change is at most $d_{\mathfrak r}\le\delta_{\mathfrak r}$. \emph{Product maps.} Fix a same-side core pair $A_0$ (the pair $a$ or the pair $c$), with normalized pair feature $\mathcal U_{A_0}$. For a core support $S$ with $2\le|S|\le4$ the product map $\mathcal U_S\times\mathcal U_{A_0}\colon\mathcal H\otimes\mathcal H\to L^2(\mu^{\rm core})$, $F\mapsto\E_{t,z}\,\mathcal U_S(\cdot;t)\,\mathcal U_{A_0}(\cdot;z)F(t,z)$ ($\mathcal H=L^2_0(\Fp)$), is bounded on three orthogonal pieces of $\mathcal H\otimes\mathcal H$: the functions vanishing on the diagonal $t=z$, the mean-zero diagonal functions $D_{\mathcal H}f=(P_0\otimes P_0)\sqrt p\,\one_{t=z}f(t)$, $f\in\mathcal H$, whose Gram is $(1-2q)I$, and the constant diagonal vector $e_0=(p\one_{t=z}-1)/\sqrt{p-1}$ of \cref{lem:swapped-rectangle}(c). With $d=|S\triangle A_0|$, $c=|S\cap A_0|$, $u=|S\cup A_0|$, the densities $\mathfrak d_2=1/(1-q)$, $\mathfrak d_3=4/((1-q)(1-3q))$, $\mathfrak d_4=16/Z_4$ of a same-side pair, a triple of core labels consisting of one same-side pair and one further core label, and the whole core relative to independent uniform labels, and the bounds $\omega_1=0$, $\omega_2=q$, $\omega_3=2r$, $\omega_4=2r+q$ for the complete character mean $|\E_t\psi_S(t)|$ of $1,\dots,4$ distinct labels, put \begin{gather*} \varrho^o_S=\begin{cases}2\sqrt{\mathfrak d_2},&S=A_0,\\\sqrt{\mathfrak d_u},&S\ne A_0,\end{cases} \qquad \varrho^d_S=\frac{\one_{d\ne0}+cr+q+\omega_{|S|}}{\sqrt{1-2q}},\qquad \varrho^c_S=\begin{cases}0,&S=A_0,\\[2pt] \dfrac{\omega_d+cq+\omega_{|S|}q}{r\sqrt{1-q}},&S\ne A_0,\end{cases}\\ R_S=\bigl((\varrho^o_S)^2+(\varrho^d_S)^2+(\varrho^c_S)^2\bigr)^{1/2}. \end{gather*} Then $\mathcal U_S\times\mathcal U_{A_0}$ has norm at most $R_S$, except that for $S=A_0$ the vector $e_0$ has the constant image $h_{A_0}\one$, $h_{A_0}=(1-2q-q^2)/(r\sqrt{1-q})$, which is set apart. Indeed, on the off-diagonal piece choose an output label in $S\setminus A_0$ and one in $A_0$: with the two auxiliary labels they span a matching or a three-edge path, of norm $q$ by two Paley transforms (\cref{lem:matching:kernel}(a)), the other labels entering as bounded multipliers and the density of the $u$ labels costing $\sqrt{\mathfrak d_u}$; for $S=A_0$ the incidence is a $K_{2,2}$, of counting norm $2p$ (\cref{thm:dl:K}), whence $2q$; the separate distinctness compressions stay in place. On $D_{\mathcal H}\mathcal H$ the image is $r^{-1}(W_{S\triangle A_0}-\text{$c$ holes}-w_{A_0}W_S-w_SW_{A_0})$, with $w_{A_0}=-q$, each hole (evaluation at a common label) costing $q$ and every nonempty star having norm at most $r$. On $e_0$ the image is $(\E_t\psi_S\psi_{A_0}-w_Sw_{A_0})/(r\sqrt{1-q})$, bounded by $\varrho^c_S$ for $S\ne A_0$ and equal to $h_{A_0}$ for $S=A_0$. A singleton inside $A_0$ times $\mathcal U_{A_0}$ costs $1/\sqrt{1-q}$ and one outside $A_0$ costs $\sqrt{\mathfrak d_3}$; so the products of $\mathbf w$, and of $\mathbf u$ and $\mathbf u\Phat$ ($\Phat$ is unitary on $\mathcal H$), with $\mathcal U_{A_0}$ have norm at most $R_{\mathbf w}=1/\sqrt{1-q}+\sqrt{\mathfrak d_3}$. With $\mathbf z=(\sum_S\sigma_S\mathcal U_S-2\mathbf u\Phat)/\sqrt{15}$ and $\sigma_{A_0}=1$, \begin{gather*} \mathbf z\times\mathcal U_{A_0}=h'_{\mathbf z}\,\one e_0^*+(\text{residual}),\qquad 0\le h'_{\mathbf z}\le h_{\mathbf z}=\frac1{r\sqrt{15(1-q)}},\\ \|\text{residual}\|\le R_{\mathbf z}=\frac{\sum_SR_S+2R_{\mathbf w}}{\sqrt{15}}, \end{gather*} the sum running over the eleven core supports. For the private pair, $\mathbf v\times\mathbf e$ has norm at most $R_{\mathbf v}=(2/(1-q))^{1/2}$, and $\mathbf e\times\mathbf e=h'_{\mathbf e}\one e_0^*+(\text{residual})$ with residual norm at most $R_{\mathbf e}=(4/(1-q)+(2r+2q)^2/(1-2q))^{1/2}$ and $0\le h'_{\mathbf e}\le h_{\mathbf e}=1/(r\sqrt{1-q})$, by the computation for $S=A_0$, the private pair being a uniform distinct pair. As $p\to\infty$, $R_{\mathbf z}$ tends to about $10.14$, $R_{\mathbf w}$ to $3$, $R_{\mathbf v}$ to $\sqrt2$ and $R_{\mathbf e}$ to $2$. The class prices are \begin{align*} \eps_{00}&=r(2\delta_{\mathfrak r}+\delta_{\mathfrak r}^2),\qquad \eps_{01,c}=2qA_{\mathfrak r}(\sqrt{30}R_{\mathbf z}+2R_{\mathbf w}),\\ \eps_{01,b}&=2q\bigl\{\sqrt{30}\sqrt{g_{\mathbf z}}\,\mathfrak r_2R_{\mathbf v} +2(\mathfrak r_2R_{\mathbf e}+h_{\mathbf e}d_{\mathfrak r})\bigr\},\\ \eps_{11,c}&=r^3\bigl\{30\bigl(R_{\mathbf z}^2+2h_{\mathbf z}R_{\mathbf z} +\tfrac{h_{\mathbf z}^2}{p-1}\bigr)+4\sqrt{30}(R_{\mathbf z}+h_{\mathbf z})R_{\mathbf w} +4R_{\mathbf w}^2\bigr\},\\ \eps_{11,b}&=r^3\bigl\{30g_{\mathbf z}R_{\mathbf v}^2 +4\sqrt{30}\sqrt{g_{\mathbf z}}\,R_{\mathbf v}(R_{\mathbf e}+h_{\mathbf e}) +4\bigl(R_{\mathbf e}^2+2h_{\mathbf e}R_{\mathbf e}+\tfrac{h_{\mathbf e}^2}{p-1}\bigr)\bigr\},\\ \eps_{02}&=2A_{\mathfrak r}N_A,\qquad \eps_{12,c}=2N_A\bigl\{\sqrt{30}(rh_{\mathbf z}+rR_{\mathbf z})+2rR_{\mathbf w}\bigr\},\\ \eps_{12,b}&=2N_A\bigl\{\sqrt{30}\sqrt{g_{\mathbf z}}\,rR_{\mathbf v} +2(rh_{\mathbf e}+rR_{\mathbf e})\bigr\},\qquad \eps_{22}=N_A^2/r, \end{align*} and, a core value counted twice and the private value once, \begin{gather*} \eps_{\rm lin}=\eps_{00}+\frac{2\eps_{01,c}+\eps_{01,b}}3+\frac{2\eps_{11,c}+\eps_{11,b}}3 +\eps_{02}+\frac{2\eps_{12,c}+\eps_{12,b}}3+\eps_{22}+qr\mathfrak r_2^2,\\ \mathfrak l_0=\frac{2\sqrt{30}\,rh_{\mathbf z}A_{\mathfrak r}+2rh_{\mathbf e}\mathfrak r_2}3 . \end{gather*} \begin{lemma}[Linear root trace]\label{lem:root-linear} Suppose $k_4r+N_A<1$. On $L^2(\mu^{\rm core}\otimes\mu^{\rm pair})$, \[ P_0(K_{\rm soft}\circ\Hbar)P_0=\frac r3\bigl(\mathcal U_a\mathcal U_c^*+\mathcal U_c\mathcal U_a^* +\mathcal U_b\mathcal U_b^*\bigr)+\mathcal R_{\rm lin},\qquad \|\mathcal R_{\rm lin}\|\le\eps_{\rm lin}, \] the leading term being the pair term of \cref{lem:root-pair-matrix} with coefficient $r/3$ per score, synthesized by the features. Moreover $\|P_0(K_{\rm soft}\circ\Hbar)\one\|\le\mathfrak l_0r+\eps_{\rm lin}$ and $\|P_0(K_{\rm soft}\circ\Hbar)\|\le r(1+2\mathfrak l_0)+\eps_{\rm lin}$, and $\mathfrak l_0\to(2\sqrt2+2)/3$. \end{lemma} \begin{proof} By \eqref{eq:root-score-feature}, $K_{\rm soft}\circ\Hs0=r\,K_{\rm soft}\circ\mathcal U_a\mathcal U_c^* +qr\,K_{\rm soft}$, and the last term has norm at most $qr\mathfrak r_2^2$ (proof of \cref{lem:root-square}); the same holds for the other scores. Expand both factors of $K_{\rm soft}=T[\mathsf R,\mathsf R]$ by \eqref{eq:l20-rectangle}: $K_{\rm soft}$ is the sum of the operators $T[X,Y]$ with $X,Y$ the rank $\mathfrak r\otimes\one$, the star $\mathsf R_\star$ or the remainder $\mathsf R_\circ$, six classes up to transposition. For a core score write the kernel of $T[X,Y]\circ\mathcal U_a\mathcal U_c^*$ at $(x,x')$ as $\E_z[X(C;b')\mathcal U_a(C;z)]\,[Y(C';b)\mathcal U_c(C';z)]$: it factors through the shared auxiliary label $z$ and the exchange of the private variables (\cref{lem:swapped-rectangle}(d)), and its norm is at most the product of the norms of the two factors, each a product map of the arms (core or pair feature factors) of $X$ or $Y$ with a pair feature. The star $\mathsf R_\star$ has the two arms $(\mathbf z,\mathbf v)$ and $(\mathbf w,\mathbf e)$ with the coefficients $\sqrt{30}\,r$ and $2r$. \emph{Rank/rank.} The factors are $\mathfrak r\,\mathcal U_a$ and $\mathfrak r\,\mathcal U_c$, so the class is $r\,(\mathfrak r\,\mathcal U_a)(\mathfrak r\,\mathcal U_c)^*$. Since $P_0(\mathfrak r\,\mathcal U_a)-\mathcal U_a=P_0((\mathfrak r-1)\mathcal U_a)$ has norm at most $\delta_{\mathfrak r}$, it is the leading term $r\,\mathcal U_a\mathcal U_c^*$ up to $\eps_{00}$ after centring on both sides. \emph{Rank/star.} The factors are $\mathfrak r\,\mathcal U_a$ (norm at most $A_{\mathfrak r}$) tensored with the private arm, and the product of the core arm with $\mathcal U_c$, with the coefficient $r\cdot r=q$ of the star and the score. By the product maps the second factor is bounded by $R_{\mathbf z}$ or $R_{\mathbf w}$ except for the large constant $h'_{\mathbf z}\one e_0^*$ of $\mathbf z\times\mathcal U_c$, which yields an operator whose input is the constant function of $x'$: a constant-to-feature rank, killed by $P_0$ on the right. The two placements give $\eps_{01,c}$. For the private score the large constant is that of $\mathbf e\times\mathbf e$; its output is $\mathfrak r$ times a constant, and $P_0(\mathfrak r h)=hP_0\mathfrak r$ is paid by $h_{\mathbf e}d_{\mathfrak r}$ in $\eps_{01,b}$. \emph{Star/star.} The coefficient is $r\cdot r\cdot r$ and the four arm pairs give the products of the bounds above. The only term with a large constant on both sides is $\mathbf z\times\mathcal U_a$ against $\mathbf z\times\mathcal U_c$ (for the private score $\mathbf e\times\mathbf e$ against itself); there the two vectors $e_0$ meet through the exchange of the auxiliary labels, and the entangled swap of \cref{lem:swapped-rectangle}(c) reduces the term to $I/(p-1)$. This gives $\eps_{11,c}$ and $\eps_{11,b}$. \emph{Classes with the remainder.} Apply $\mathsf R_\circ$ fibrewise in its own core and private variables, keeping the shared auxiliary label (it is not duplicated), then the free feature on the other side: rank/remainder costs $2A_{\mathfrak r}N_A$, star/remainder $\eps_{12,c}$ or $\eps_{12,b}$ (here the large constant costs $rh_{\mathbf z}$ or $rh_{\mathbf e}$), and remainder/remainder $N_A^2/r$, the raw pair rows having norm at most one. Averaging the three scores, a core value twice and the private value once, gives the first assertion. The constant-to-feature ranks are explicit: at a core score the vector obtained by contracting $e_0$ with $\mathfrak r\,\mathcal U\otimes\mathbf v$ has norm at most $A_{\mathfrak r}$ and mean zero, by translation invariance and independence, with the coefficient $\sqrt{30}\,rh_{\mathbf z}\cdot r$; at the private score the vector from $\mathbf w\otimes\mathbf e$ has norm at most $\E\mathfrak r\le\mathfrak r_2$, with the coefficient $2rh_{\mathbf e}\cdot r$. Exactly one of the two orientations survives in $P_0(K_{\rm soft}\circ\Hbar)\one$, which gives $\mathfrak l_0r$ rather than twice that number; the other parts of $P_0(K_{\rm soft}\circ\Hbar)\one$ are bounded by their norms. The leading pair term has norm at most $r$, which gives the bound for $\|P_0(K_{\rm soft}\circ\Hbar)\|$. As $p\to\infty$, $A_{\mathfrak r},\mathfrak r_2\to1$ and $\mathfrak l_0\to(2\sqrt{30}/\sqrt{15}+2)/3$. \end{proof} \begin{lemma}[Normalization, marginal and conditional prices]\label{lem:root-normalization} Let $p\ge2^{20}$. Put \begin{gather*} \bar{\mathfrak r}=\frac{1+2\mathfrak m_++d_{\mathsf K}^2}{1-q},\qquad \mathfrak s_b=\frac{512\,\bar{\mathfrak r}q^2}{1-q},\qquad \mathfrak s_c=\frac{32\,\mathfrak r_+(1+\eta)^2q^2}{Z_4},\qquad \mathfrak s=\frac{2\mathfrak s_c+\mathfrak s_b}3,\\ c_{\rm lin}=(2+r)D_{\rm bal}+\frac{\mathfrak s}{h'_pr},\qquad \eps^{\rm raw}_{\rm lin}=\frac{\eps_{\rm lin}}{h'_p}+c_{\rm lin},\\ \eps^{\rm raw}_{\rm sq}=\frac{4q\mathfrak r_2^2+256c_0\mathfrak r_+q}{h'_p} +\bigl((2+r)^2-1\bigr)D_{\rm bal}+\frac{\mathfrak s}{h'_pq},\qquad \eps_{\rm sq}=\frac{\eps^{\rm raw}_{\rm sq}}{1-\eps_Z},\\ \mathfrak l=\frac1{1-\eps_Z}\Bigl\{\frac{\mathfrak l_0r+\eps_{\rm lin}}{\sqrt{h'_p}} +\frac{[r(1+2\mathfrak l_0)+\eps_{\rm lin}]\sqrt{8q/(1-q)}}{h'_p}+c_{\rm lin}\Bigr\},\\ h_0=\frac{72q+37qr+2qr/(1-q)}{1-36q}. \end{gather*} \begin{enumerate}[label=(\alph*)] \item If $k_4r+N_A<1$, then in the fixed half chart $L^2(\mu_p)$, $\bigl\|K_0\circ\tfrac13\sum_j\Hs j^2-K_0\bigr\|\le\eps^{\rm raw}_{\rm sq}$ and \[ \Bigl\|P_0(K_0\circ\Hbar)P_0-\frac r3\,\mathcal F\bigl(e_{01}e_{45}^*+e_{45}e_{01}^* +e_{23}e_{23}^*\bigr)\mathcal F^*\Bigr\|\le\eps^{\rm raw}_{\rm lin}; \] consequently $\bigl\|T_0\circ\tfrac13\sum_j\Hs j^2-T_0\bigr\|\le\eps_{\rm sq}$ and $\|P_0(T_0\circ\Hbar)\one\|\le\mathfrak l$. \item For each score, $|\E_{\Gamma_{p,0}}\Hs j|\le h_0$ and $\E_{\Gamma_{p,0}}\Hs j^2\ge1-4q-36q(2+r)^2-2q/(1-q)$; in particular $|\E_{\Gamma_{p,0}}\Hbar|\le h_0$. \item Put $\Delta_{\rm core}=(1-q)^4-16r-144q-512qr-512q^2$, positive for $p\ge2^{20}$, and \begin{gather*} c_{\rm core}=\frac{148q+616qr+580q^2}{r\Delta_{\rm core}}+2r,\qquad \varphi_b=\frac{24r+8q}{1-\eta},\qquad d_b=\frac{16q}{1-\eta-16q},\\ c_b=\frac{4q+(1+d_b)\varphi_b^2+d_b}r,\qquad c_{\rm avg}=\frac{2c_{\rm core}+c_b}3,\qquad I_{\rm in}=\frac{128\,q\,\mathfrak r_+\bar{\mathfrak r}}{1-\eta},\qquad \rho_{\rm in}=\mathfrak r_-^2-I_{\rm in}-D_{\rm bal}. \end{gather*} If $\rho_{\rm in}>0$, then for every half $x$ \[ \bigl|\E_{\Gamma_{p,0}}[\Hbar\mid x]\bigr|\le c_{\rm cond} :=\frac{\mathfrak r_+\bar{\mathfrak r}\,c_{\rm avg}+(2+r)(I_{\rm in}+D_{\rm bal}) +\mathfrak s/r}{\rho_{\rm in}} . \] \end{enumerate} \end{lemma} \begin{proof} (a) \emph{Spikes.} $\bar{\mathfrak r}$ bounds $\E\mathfrak r\le\E\bar{\mathsf K}^2/(1-q)$, as $\E\bar{\mathsf K}^2\le1+2\mathfrak m_++d_{\mathsf K}^2$. When the two halves share a label, the only large values of a score occur when the two selected pairs are equal as sets; there $\Hs j=(1-2q)/r$, and otherwise $|\Hs j|\le2+r$. For the private score, $\{b'\}=\{b\}$ has probability $2q^2/(1-q)$ and $\mathsf R\le256$; integrating the core of the other half gives the column mass $\E\mathfrak r\le\bar{\mathfrak r}$, so the rows and columns of the soft kernel on this event are at most $\mathfrak s_b$. For a core score, $\{c'\}=\{a\}$ has the same probability; given it, the labels $a'$ are a uniform ordered distinct pair among the $(p-3)/4$ common predecessors of the pinned pair (\cref{lem:paley-triple}(a)), and both must lie in the set of labels that extend $(b,c')$ cyclically, of at most $p(1+\eta)/16$ points, so the conditional mean of $\mathsf R(C';b)$ is at most $16(1+\eta)^2/((1-3q)(1-7q))$; integrating the pair of the other half gives $\mathfrak r(C)\le\mathfrak r_+$, and this gives $\mathfrak s_c$. Away from these events a score has $|\Hs j|\le2+r$, as a single repeated label leaves a character sum of degree two, so $|\Hs j^2-1|\le(2+r)^2-1$, and the nonnegative kernel $T_{\rm coll}$ contributes in the displayed directions. The spike prices are row and column bounds of nonnegative kernels (Schur's test), compressed with the factor $1/h_p\le1/h'_p$. \emph{Squares.} For $V=\frac13\sum_j\Hs j^2$, $K_0\circ V-K_0=h_p^{-1}J_\mu^*(K_{\rm soft}\circ V-K_{\rm soft})J_\mu -T_{\rm coll}\circ(V-1)$, and \cref{lem:root-square,lem:restriction}(b) bound the first term by $(4q\mathfrak r_2^2+256c_0\mathfrak r_+q)/h'_p$; with the collision bounds this is $\eps^{\rm raw}_{\rm sq}$, and division by $Z_0\ge1-\eps_Z$ gives $\eps_{\rm sq}$. \emph{Linear term.} By \cref{lem:restriction}(a) the embedding maps centred functions to centred functions and $J_\mu^*\one=\sqrt{h_p}\one$, so $P_0(K^\mu_{\rm soft}\circ\Hbar)P_0=h_p^{-1}P_0J_\mu^*\bigl[P_0(K_{\rm soft}\circ\Hbar)P_0\bigr] J_\mu P_0$. By \cref{lem:root-linear} and the identity $J_\mu^*Y=\sqrt{h_p}Y_\mu$ for the features, the leading term becomes $\frac r3\mathcal F(e_{01}e_{45}^*+e_{45}e_{01}^*+e_{23}e_{23}^*)\mathcal F^*$ and the remainder has norm at most $\eps_{\rm lin}/h'_p$; the collision part $T_{\rm coll}\circ\Hbar$ has norm at most $c_{\rm lin}$. For the marginal, \cref{lem:restriction}(b) with both events of probability $h_p$ gives \[ \|P_0(K^\mu_{\rm soft}\circ\Hbar)\one\|\le\frac{\|P_0(K_{\rm soft}\circ\Hbar)\one\|}{\sqrt{h_p}} +\|P_0(K_{\rm soft}\circ\Hbar)P_0\|\,\frac{(1-h_p)^{1/2}}{h_p}, \] where $1-h_p=(8q-20q^2)/(1-q)\le8q/(1-q)$ and \cref{lem:root-linear} bounds the two norms. Adding $c_{\rm lin}$ and dividing by $Z_0$ gives $\mathfrak l$. (b) Before global injectivity the root is the product of the uniform laws of its two components, each a cyclic $K_{2,2,2}$ on the bases of one parity (the parts being the two layer labels at each of the three bases, with all edges directed cyclically to the next base), and each score pairs the two labels of one base of one component with those of a base of the other. Each such pair is a uniform ordered distinct pair: square-affine maps act transitively on each of the two orbits of ordered distinct pairs and the layer swap exchanges them. Hence, with $\E\psi_y(z)=-q$, $\E\Hs j=r^{-1}\E_z(\E\psi_y(z))^2=qr$, and \[ \E\Hs j^2=q^{-1}\E_{z,z'}\bigl(\E_y\psi_y(z)\psi_y(z')\bigr)^2 =(1-2q)^2+\frac{q(1-3q)^2}{1-q}\ \ge\ 1-4q, \] as $\E_y\psi_y(z)^2=1-2q$ and $\E_y\psi_y(z)\psi_y(z')=-q(1-3q)/(1-q)$ for $z\ne z'$. The thirty-six coincidences between the labels of the two components have total probability at most $36q$; on them $|\Hs j|\le2+r$, except on the events where the two selected pairs are equal as sets, of probability at most $2q^2/(1-q)$, where $|\Hs j|\le1/r$. Conditioning on injectivity therefore gives $|\E_{\Gamma_{p,0}}\Hs j|\le(qr+36q(2+r)+2qr/(1-q))/(1-36q)=h_0$ and $\E_{\Gamma_{p,0}}\Hs j^2\ge\E\Hs j^2-36q(2+r)^2-2q(1-2q)^2/(1-q)$, whence the bounds. (c) Fix $x=(C,b)$. On $\mu^{\rm core}\otimes\mu^{\rm pair}$ the soft conditional law of $x'=(C',b')$ given $x$ is proportional to $\mathsf R(C;b')\mathsf R(C';b)$; it is the product of a law of $C'$ that depends on $b$ and a law of $b'$ that depends on $C$, and $\E_{x'}K_{\rm soft}(x,x')=\mathfrak r(C)\E\mathfrak r$. \emph{A core score.} Take $\Hs0$, which tests the pair $c'$ of $C'$: $\E[\Hs0\mid x]=r^{-1}\E_z\psi_a(z)\,\E[\psi_{c'}(z)\mid b]$. In independent uniform labels $(a'_0,a'_1,c'_0,c'_1)$ the law of $C'$ given $b$ has a density proportional to the product of the four internal edge factors $1+\chi(c'_j-a'_i)$, of the vertex weights $w_A(a'_i)$ and $w_C(c'_j)$, with $w_A(y)=(1-\chi(b_0-y))(1-\chi(b_1-y))$ and $w_C(y)=(1+\chi(b_0-y))(1+\chi(b_1-y))$, and of the indicator that the four labels are distinct. Each weight has mean $1-q$, $L^2$ norm at most $2$ and supremum at most $4$; testing a vertex by $\chi(z-y)$, for $z\notin\{b_0,b_1\}$, gives a weight of mean at most $2r+2q$ in modulus (two quadratic character sums contribute $q$ each and the cubic one $2r$), with the same norm bounds. Expand the four internal edge factors into the $16$ subsets of edges. A single edge, a Paley operator of norm $r$ between two weights of norm $2$, costs $4r$; each of the two matchings costs $16q$; each of the four adjacent two-edge paths costs $16q$ (integrate the two leaf Paley transforms first and use the supremum of the internal weight); each of the four three-edge paths costs $64qr$; and the cycle costs $16q$, as a product of two operators $M_{w_1}PM_{w_2}P$, each of Hilbert--Schmidt norm at most $4r$. The distinctness costs only the same-side coincidences: $w_A(y)w_C(y)=(1-\chi(b_0-y)^2)(1-\chi(b_1-y)^2)=0$ kills the four cross-side ones, and on a same-side coincidence $w^2\le4w$ and every doubled edge factor is at most twice the original, so its mass is at most $16q\,\E_a[w_A(a)(\E_cw_C(c)(1+\chi(c-a)))^2]\le16q(1+8r+16q)$; the two such events cost $C_{\rm coll}=32q+256qr+512q^2$. Without tests this bounds the normalizing mass below by $(1-q)^4-16r-112q-256qr-C_{\rm coll}=\Delta_{\rm core}$. With the two vertices of $c'$ tested, the empty graph gives $m^2$, the four single edges $16rm$, the matchings $32q$, the two paths centred on the untested side $32q$, the two paths centred at a tested vertex $32qm$, the three-edge paths $256qr$, the cycle $16q$ and the coincidences $C_{\rm coll}$; the sum is \[ m^2+16rm+80q+32qm+256qr+C_{\rm coll}=148q+616qr+580q^2 . \] Hence $|\E[\psi_{c'}(z)\mid b]|\le(148q+616qr+580q^2)/\Delta_{\rm core}$ for $z\notin\{b_0,b_1\}$, and the two exceptional labels cost $2q$, which gives the soft bound $c_{\rm core}$. The lower bound $\Delta_{\rm core}$ increases with $p$ and is positive at $p=2^{20}$, hence for $p\ge2^{20}$. \emph{The private score.} $\E[\Hs1\mid x]=r^{-1}\E_z\psi_b(z)\E[\psi_{b'}(z)\mid C]$, and given $C$ the pair $b'$ is a uniform ordered distinct pair from the set $L_C$ of cyclic extensions of $C$, of $n=p\bar{\mathsf K}(C)/16\ge p(1-\eta)/16$ points. For $z\notin C$, expanding $\mathsf K(t,C)\chi(z-t)$ in $t$ gives $|\E_{t\in L_C}\chi(z-t)|\le\varphi_b$: the four terms with one further character cost $q$ each, the six cubic terms $2r$ each, the four quartic terms $2r+q$ each (\cref{thm:weil}(b)) and the quintic term $4r$, and the mass is $\bar{\mathsf K}\ge1-\eta$. Sampling without replacement gives $\E\chi(z-b'_0)\chi(z-b'_1)=(n\gamma_C^2-\E_{t\in L_C}\chi(z-t)^2)/(n-1)$ with $\gamma_C=\E_{t\in L_C}\chi(z-t)$, of modulus at most $(1+d_b)\varphi_b^2+d_b$, as $1/(n-1)\le d_b$; the four labels $z\in C$ cost $4q$. This gives the soft bound $c_b$, and $c_{\rm avg}$ for $\Hbar$. \emph{The row of the actual kernel.} (``Physical'' in this proof means: of the actual kernel $K_0$, as opposed to the soft kernel $K_{\rm soft}$.) The soft row of $K_{\rm soft}\circ\Hbar$ at $x$ is at most $c_{\rm avg}\,\mathfrak r(C)\E\mathfrak r\le\mathfrak r_+\bar{\mathfrak r}\,c_{\rm avg}$ in modulus, and the soft row of $K_{\rm soft}$ is at least $\mathfrak r_-^2$. Passing to the physical conditional law removes, first, the eight coincidences of $b'$ with the core $C'$, which are excluded from the actual half: given $C$ the pair $b'$ is uniform in $L_C$, so each costs at most $16q/(1-\eta)$ of the row mass $\mathfrak r(C)\E\mathfrak r$, together $I_{\rm in}$; second, the coincidences across the cut, of row mass at most $D_{\rm bal}$ (\cref{prop:l20-collisions}(a), the compression factor $h_p\le1$ being used in the conservative direction); third, the equal-pair spikes, of score at most $1/r$ and row mass at most $\mathfrak s$. On the first two kinds $|\Hbar|\le2+r$. The ratio of the remaining numerator and denominator is at most $c_{\rm cond}$. \end{proof} The conditional bound $c_{\rm cond}$ is about $299r$; it is used only for the range of the tilted marginal, by Jensen's inequality in \cref{lem:tilt-marginals}, while the much smaller $L^2$ bound $\mathfrak l$ prices its variance. \begin{proposition}[The chamber cut of a positive root]\label{prop:root-chamber} Let $p\ge2^{30}$, suppose $k_4r+N_A<1$ and $\rho_{\rm in}>0$, and let $\Gamma_{p,\ulaw}$ be the individual-square root, with $s=1+\ulaw^2$, $\lambda=2\ulaw/s$, and $g=g(\lambda)$ of \eqref{eq:root-cubic}. Put \begin{gather*} \eps_0=\frac{2rd_{\mathfrak r}(\sqrt{30}\sqrt{g_{\mathbf z}}+2)+k_4^2q+2\mathfrak r_2N_A +2k_4rN_A+N_A^2}{h'_p}+D_{\rm bal},\qquad \eps_\ulaw=s\eps_0+2\ulaw\eps^{\rm raw}_{\rm lin}+\ulaw^2\eps^{\rm raw}_{\rm sq},\\ z_-=s-2\ulaw h_0-\ulaw^2\eps_{\rm sq},\qquad z_{\rm raw}=(1-\eps_Z)z_-,\qquad g_{\rm ch}=\frac{sg\,r\Gamma_{20}+\eps_\ulaw}{z_{\rm raw}},\\ c_{\rm ch}=\frac{s(\sqrt{30}+\lambda/3)r\Gamma_{20}+\eps_\ulaw+sd_{\mathfrak r}^2/h'_p}{z_{\rm raw}}, \qquad d_\ulaw=\frac{s\sqrt{\chi^+_p}+2\ulaw\mathfrak l+\ulaw^2\eps_{\rm sq}}{z_-}. \end{gather*} If $z_->0$, $\ulaw c_{\rm cond}<1$, $c_{\rm ch}<1$ and $d_\ulaw<1$, the cut operator $T_\ulaw$ of $\Gamma_{p,\ulaw}$ at $\vartheta_0$ in the fixed uniform actual half chart $L^2(\mu_p)$ satisfies \begin{gather*} -\Bigl(g_{\rm ch}+\frac{d_\ulaw^2}{1+g_{\rm ch}}\Bigr)I\preceq T_\ulaw\preceq \Bigl(1+\frac{d_\ulaw^2}{1-c_{\rm ch}}\Bigr)I,\qquad \|T_\ulaw\one-\one\|^2\le d_\ulaw^2,\\ \frac{\sup T_\ulaw\one}{\inf T_\ulaw\one}\le R_p\,\frac{(1+\ulaw(2+r))^2}{(1-\ulaw c_{\rm cond})^2}. \end{gather*} With $g^\ulaw_{20}=(g_{\rm ch}+d_\ulaw^2/(1+g_{\rm ch}))/r$ and $c^{+,\ulaw}_{20}=d_\ulaw^2/(q(1-c_{\rm ch}))$ evaluated at an endpoint $P$, the same bounds, $-g^\ulaw_{20}p^{-1/2}\le T_\ulaw\le1+c^{+,\ulaw}_{20}/p$, the variance $d_\ulaw^2$ and the range ratio hold for every prime $p\ge P$ with the same $\ulaw$. The block caps follow from \cref{lem:spec:tensorcomp}(b): a middle block $\Blk$ of a piece starting at $X\ge P$, with least prime $b$ and $\sum_{p\in\Blk}\log p\le L_{\rm loc}$, has $T_{\Blk,\ulaw}\succeq-g^\ulaw_{20}\exp\bigl(c^{+,\ulaw}_{20}L_{\rm loc}/(X\log X)\bigr)b^{-1/2}$ if $g^\ulaw_{20}X^{-1/2}<1$. \end{proposition} \begin{proof} \emph{The base kernel.} Expand $K_{\rm soft}=T[\mathsf R,\mathsf R]$ by \eqref{eq:l20-rectangle} and keep the positive rank: $T[\mathfrak r\otimes\one,\mathfrak r\otimes\one]$ is the rank-one operator $(\mathfrak r\otimes\one)\ip{\mathfrak r\otimes\one}{\cdot}$. The two rank/star classes are the star part $T_\star=r\{\sqrt{30}(\mathbf v\mathbf z^*+\mathbf z\mathbf v^*) +2(\mathbf w\mathbf e^*+\mathbf e\mathbf w^*)\}$ of \eqref{eq:l20-rank4-operator}, up to the factor $\mathfrak r$ on one side, which costs $2rd_{\mathfrak r}(\sqrt{30}\sqrt{g_{\mathbf z}}+2)$; star/star costs $k_4^2q$, rank/remainder $2\mathfrak r_2N_A$, star/remainder $2k_4rN_A$ and remainder/remainder $N_A^2$, as $\|T[X,Y]\|\le\|X\|\|Y\|$. The compression to $\mu_p$ (\cref{lem:restriction}) and the collisions give, in the coefficient space, \[ P_0K_0P_0=r\,\mathcal FM\mathcal F^*+P_0\mathfrak r_\mu\mathfrak r_\mu^*P_0+\mathcal R_0, \qquad\|\mathcal R_0\|\le\eps_0, \] where $\mathfrak r_\mu$ is the function $\mathfrak r(C)$ on the actual half; the centred rank $P_0\mathfrak r_\mu\mathfrak r_\mu^*P_0$ is positive semidefinite, of norm at most $\|\mathfrak r-1\|_2^2/h_p\le d_{\mathfrak r}^2/h'_p$, and enters only the absolute norm. \emph{The tilt.} By \cref{def:positive-root}, $K_0\circ w_\ulaw=K_0+2\ulaw\,K_0\circ\Hbar+\ulaw^2\,K_0\circ V$ with $V=\frac13\sum_j\Hs j^2$. By \cref{lem:root-normalization}(a), $K_0\circ V=K_0+\mathcal R_V$ with $\|\mathcal R_V\|\le\eps^{\rm raw}_{\rm sq}$, and $P_0(K_0\circ\Hbar)P_0$ is the pair term up to $\eps^{\rm raw}_{\rm lin}$. As $1+\ulaw^2=s$ and $2\ulaw/s=\lambda$, \[ P_0(K_0\circ w_\ulaw)P_0=s\,r\,\mathcal FM_\lambda\mathcal F^* +sP_0\mathfrak r_\mu\mathfrak r_\mu^*P_0+\mathcal R_\ulaw,\qquad\|\mathcal R_\ulaw\|\le\eps_\ulaw . \] By \cref{lem:root-pair-matrix}, applicable since $\lambda\le1$, $M_\lambda\succeq-gI$ and $\|M_\lambda\|\le\sqrt{30}+\lambda/3$, so $\mathcal FM_\lambda\mathcal F^*\succeq-g\Gamma_{20}$ and $\|\mathcal FM_\lambda\mathcal F^*\|\le(\sqrt{30}+\lambda/3)\Gamma_{20}$, the features mapping into mean-zero functions. \emph{Mass, marginal and range.} Apply \cref{lem:tilt-marginals} to the kernel of $T_0$, which has mass one, $\|T_0\one-\one\|\le(\chi^+_p)^{1/2}$ (\cref{lem:record:root-marginal}(ii)) and range ratio $\sup T_0\one/\inf T_0\one\le R_p$: by \eqref{eq:record:root-count} the density is a ratio of completion counts between two bounds whose quotient is $R_p$. Take the scores $\eta_j=\Hs j$, which the transposition permutes (\cref{lem:positive-root-properties}(c)), and the constants \[ (c_V,\delta_0,e,\ell,h,c,b)=\bigl(1,(\chi^+_p)^{1/2},\eps_{\rm sq},\mathfrak l, h_0,c_{\rm cond},2+r\bigr) \] of \cref{lem:root-normalization} and \cref{lem:positive-root-properties}(a). It gives $\E_{\Gamma_{p,0}}w_\ulaw\ge z_-$, $\|T_\ulaw\one-\one\|\le d_\ulaw$ and the range ratio. Since the raw mass of $K_0\circ w_\ulaw$ is $Z_0\,\E_{\Gamma_{p,0}}w_\ulaw\ge z_{\rm raw}$, $P_0T_\ulaw P_0\succeq-g_{\rm ch}P_0$ and $\|P_0T_\ulaw P_0\|\le c_{\rm ch}$. \emph{The constant block.} $T_\ulaw$ is self-adjoint with $\ip\one{T_\ulaw\one}=1$ and $\|P_0T_\ulaw\one\|=\|T_\ulaw\one-\one\|\le d_\ulaw$, so \cref{prop:matching:positive}(a) and (a$'$) give the two full bounds; no alignment of spectral directions is assumed. \emph{Uniformity.} The quantities $\mathfrak r_-$, $h'_p$, the square term $4q\mathfrak r_2^2$ and the conditional ratio were coarsened so that every normalized remainder has a positive increasing numerator and a positive decreasing denominator in $q,r$; the retained $N_A/q$, $D_{\rm bal}/q$, frame cap, normalizer error, $\chi^+_p$ and $R_p$ have this property (\cref{prop:l20-collisions}, \cref{lem:record:root-marginal}). Thus $G=g_{\rm ch}/r$, $c_{\rm ch}/r$ and $D=d_\ulaw/r$ increase toward a smaller prime endpoint. The negative coefficient is $G+D^2r/(1+Gr)$; its derivative in $G$ is $1-D^2r^2/(1+Gr)^2>0$, as $Dr<1$, and its derivatives in $D$ and $r$ are nonnegative (\cref{lem:majorant}(ii)). The positive coefficient $D^2/(1-(c_{\rm ch}/r)\,r)$, the variance divided by $q$ and the range multiplier increase as well on the gated domain, so the values at $P$ bound every prime $p\ge P$. For the block caps, the primes of $\Blk$ satisfy the prime bounds and $\sum_{p\in\Blk}1/p\le L_{\rm loc}/(X\log X)$ (\cref{lem:record:local-domain}), the cut operator of $\Gamma_{\Blk,\ulaw}$ is the tensor product of the prime operators (\cref{lem:spec:cutkernel}(f)), and \cref{lem:spec:tensorcomp}(b) applies. \end{proof} \subsection{The layer-flip symmetry \texorpdfstring{$\iota$}{iota} for the tilted law}\label{subsec:positive-root-layer} This subsection bounds the reserved cut $\iota$ of a positive root, the cut L21. Here the scores are positive Gram kernels, so the tilt costs only at order $r$; the bounds are proved on the fixed uniform induced layer half, the half law of the one-layer root, which is not tilted. \paragraph{The two components.} At $\iota$ the half graph of $G_{\rm L,2}$ is $G_{\rm L,1}$, two directed triangles on the bases $\{0,2,4\}$ and $\{1,5,3\}$ (\cref{lem:layer12-geometry}(c)). Let $\mu_\triangle$ be the uniform law of a directed cyclic triangle $x_0\to x_1\to x_2\to x_0$ of $\Fp$, let $\nu_\triangle=\mu_\triangle\otimes\mu_\triangle$ (one triangle for each component), and let $\nu=\lambda_p(G_{\rm L,1})$ be $\nu_\triangle$ conditioned on its six labels being distinct, an event of probability $h\ge h_-=1-9q$. In a component, with the labels $x$ of the layer $0$ and $x'$ of the layer $1$ indexed along the triangle, the cross edges are $x_i\to x'_{i+1}$ and $x'_i\to x_{i+1}$: a six-cycle without an edge between the two labels of one base. The soft kernel of a component is \[ \Phi(x,x')=\prod_{i\ne j}\bigl(1+(D_\triangle)_{ij}\chi(x'_j-x_i)\bigr),\qquad N_\Phi=\Phi-1, \] $D_\triangle$ being the skew adjacency matrix of the directed triangle ($(D_\triangle)_{i,i+1}=1$, $(D_\triangle)_{i+1,i}=-1$ with indices mod $3$, and $0$ on the diagonal), and the soft layer kernel on $\nu_\triangle\otimes\nu_\triangle$ is $\Phi\otimes\Phi$. A score $\Hs j$ multiplies the kernel by $r^{-1}\ip{f_j(x)}{f_j(x')}$, $f_j(x)(z)=\chi(z-x_j)\chi(z-x_{j+3})$, the product of the raw pair rows of the two selected labels of a half, one from each component. Put \begin{gather*} d_2=\frac2{1-q},\quad d_\mu=\frac8{1-q^2},\quad \kappa=\frac{\sqrt3+\sqrt7}2,\\ \mathfrak b=6+15d_2+18\sqrt{d_2d_\mu}+4d_\mu+14d_\mu r,\quad \mathfrak n=\kappa(1+5r)r+\mathfrak bq,\quad M_\Phi=d_\mu(1+q)^3,\\ Z_-=(1-\mathfrak bq)^2-q\bigl[18M_\Phi^2+384M_\Phi+72d_\mu^2(1+q)^5\bigr], \end{gather*} and let $p\ge2^{30}$. The following facts hold for every score. \begin{enumerate}[label=(L\arabic*)] \item $\|N_\Phi\|\le\mathfrak n$ and $\|N_\Phi\one\|\le\mathfrak bq$ on $L^2(\mu_\triangle)$. Indeed the six single edges and the six two-edge stars have the coefficient matrix $\left(\begin{smallmatrix}iD_\triangle&-I_3\\-I_3&0\end{smallmatrix}\right)$ (\cref{cor:star-matrix}), whose characteristic polynomial is $(z^2-1)(z^4-5z^2+1)$ and whose norm is $\kappa$. The six features (the coordinate isometries $V_i$ and the pair stars $W_{\{j,k\}}/r$) have actual Gram at most $(1+5r)I$ for $p\ge2^{20}$ (\cref{lem:general-star}): the off-diagonal norms are at most $r\sqrt{1+q}/(1-q)$ (singleton/singleton), $2q/(1-q)$ (incident singleton/pair), exactly $r$ (opposite singleton/pair: condition on that coordinate and negate while swapping the other two) and $(3q+\sqrt3r)/(1-q)$ (pair/pair), with row sums at most $5r$. The uncentred stars leave $+6q$ times the constant kernel, each pair mean being $-q$ and each star coefficient $-1$. The remaining $51$ masks can be priced using just their active coordinates. The one-, two-, and three-coordinate densities of a directed triangle are $1,d_2,d_\mu$. A kernel using $u$ output and $v$ input coordinates therefore incurs only $\sqrt{d_ud_v}$. The exact mask partition is \[ \begin{array}{c|c|c|c} \text{mask type}&(u,v)&\text{number}&\text{bound per mask}\\ \hline \text{two-edge matching or forest}&(2,2)&15&d_2q\\ \text{matching number two forest}&(2,3),(3,2)&9+9&\sqrt{d_2d_\mu}q\\ \text{two disjoint two-edge stars}&(3,3)&3&d_\mu q\\ \text{matching number three forest}&(3,3)&14&d_\mu rq\\ \text{full six-cycle}&(3,3)&1&d_\mu q \end{array} \] A path of $k\le5$ edges has full-cube norm at most $r^{\lceil k/2\rceil}$: the two-edge star has squared norm $q(1-q)$, the three- and five-edge paths factor into Paley transforms with intervening contractions, and the four-edge path is bounded by fixing its middle vertex and applying two transforms. Disconnected components tensor. For the full cycle, fix one coordinate on each side and apply the two-edge matching/path bound, at cost $q$; no $r^3$ estimate for that cycle is used. Summing the table and the six means gives $\mathfrak b$. In particular \[ \mathfrak b\le6+\frac{102}{1-q} +\frac{32+112r}{1-q^2}<140.004 \qquad(p\ge2^{30}), \] with limit $140$. All these majorants are increasing in $q,r$. \item The passive selected-coordinate maps $h\mapsto\E_z\chi(z-y)h(z)$ and $F\mapsto\E_{z,z'}\chi(z-y)\chi(z'-y)F(z,z')$ have norms $r$ and $(q(1-q))^{1/2}$ (\cref{cor:raw-pair-maps}(a)). \item \emph{Insertion of a score multiplier in a monomial of $N_\Phi\otimes N_\Phi$.} In a monomial of $N_\Phi\otimes N_\Phi$ choose one cross edge in each component; it has at most one endpoint among the selected labels of a score, as no cross edge joins the two labels of a base. With the other vertices pinned, a bounded multiplier depending on at most one endpoint of each chosen edge can be placed between the two Paley transforms, or before or after their tensor product, so the kernel has norm at most $q$ times the supremum of the multiplier (\cref{lem:matching:kernel}(d)). Given the other two vertices of a triangle, the active vertex has exactly $(p+1)/4$ completions (\cref{lem:paley-triple}(a)), a conditional density at most $4/(1+q)\le4$; Cauchy--Schwarz over the pinned vertices recovers the triangle energies, at the cost $16$. \item \emph{Rows and coincidences.} Each two-edge column of $\Phi$ has uniform mean $1+q$, so the rows of $\Phi$ are at most $M_\Phi$. A cross-component equality across the cut costs at most $4d_\mu^2(1+q)^5q$ of row mass (given a coordinate, the other two of its triangle have density $d_\mu$), a twin equality $x_u=x'_u$ at most $64M_\Phi q$, an equality between the two components inside one half at most $M_\Phi^2q$ (integrate the other half against the two row bounds), and a same-component equality at different bases makes $\Phi$ vanish, the third base supplying a contradictory edge. The soft mass is at least $(1-\mathfrak bq)^2$ by (L1); counting the eighteen cross-component coincidences inside the two halves, the six twins and the eighteen cross-component coincidences across the cut, the raw mass of the uniform root relative to $\nu\otimes\nu$ is at least $Z_-$; division by the half probability squared only increases it. \end{enumerate} \begin{lemma}[Inserting an opposite-base-pair score into the soft kernel]\label{lem:native-pair-linear} Fix one of the opposite-base-pair scores $\Hs0,\Hs1,\Hs2$ introduced above and denote it by $\mathsf H$. On the two independent cyclic triangles put $K=\Phi\otimes\Phi$, $e=\mathfrak b-6$. Then, for $p\ge2^{30}$, \[ \|K\circ\mathsf H-\mathsf H\|\le C_{\rm pair}q,\qquad C_{\rm pair}=2304+2\kappa(1+5r)(1+e) +r(12+14e+e^2)<2897. \] Restriction to the actual six-distinct half costs at most $(1-9q)^{-1}$. Cross-cut collisions must still be charged separately. \end{lemma} \begin{proof} Keep the same auxiliary label in the two raw pair rows. For an operator $A$ on the first triangle, let \[ (VF)(x,y)=\E_s\chi(s-x_i)\chi(s-y_j)F(x,s). \] Uniformity of $y_j$ and the Paley bound give $\|V\|\le r$, while direct composition gives $(A\otimes J)\circ\mathsf H=r^{-1}V(A\otimes I)V^*$. Thus this term has norm at most $r\|A\|$. Write $\Phi=J+S+R$, with $S$ the twelve raw star monomials. The preceding bounds give $\|S\|\le\kappa(1+5r)r+6q$ and $\|R\|\le eq$. Each nonempty old-edge monomial times $\mathsf H$ costs at most $16q$: select one old edge and the passive score coordinate in the other triangle. The passive Paley map and the two-edge matching/path bound leave $r^3$ before the raw factor $r^{-1}$; the conditional triangle densities cost $16$. The absence of an old edge at the selected base is used here. Apply this bound to the $12^2=144$ terms of $S\otimes S$. The one-sided $S$ and $R$ terms use the displayed sandwich. The remaining $R\otimes S$, $S\otimes R$, $R\otimes R$ terms use the Schur multiplier norm at most $r^{-1}$ of the positive raw pair Gram. Summing gives the stated bound $C_{\rm pair}q$. The endpoint inequality uses $r\le2^{-15}$ and the rational upper bound for $\mathfrak b$ above. Conditioning both half laws on six distinct labels gives the single factor $(1-9q)^{-1}$. \end{proof} \begin{proposition}[The layer cut of a positive root]\label{prop:root-layer} Let $p\ge2^{30}$ and let $\Gamma_{p,\ulaw}$ be the individual-square root, with $\gamma=\ulaw^2$. Let $\nu$ be the fixed uniform induced layer half. With $d_\mu,\mathfrak b,\mathfrak n,M_\Phi,Z_-$ as above and $h_0$ of \cref{lem:root-normalization}, put $B_H=2+r$ and \begin{gather*} m_\ulaw=1+2\ulaw r+\gamma,\qquad F_\ulaw=1+2\ulaw B_H+\gamma B_H^2,\qquad C_{\rm nn,\ulaw}=3969\cdot16\,F_\ulaw,\\ C_{\rm sc,\ulaw}=127\bigl[4(1+4\ulaw r+4\gamma q)+2(q+2\ulaw r+\gamma)\bigr],\qquad C_{\rm cr,\ulaw}=\bigl[256M_\Phi+64d_\mu^2(1+q)^5\bigr]F_\ulaw,\\ C_\ulaw=C_{\rm nn,\ulaw}+C_{\rm sc,\ulaw}+C_{\rm cr,\ulaw},\qquad C_{\rm in,\ulaw}=127\bigl[9F_\ulaw+2(q+2\ulaw r+\gamma)\bigr],\\ z^\iota_\ulaw=1+\gamma-\gamma\Bigl[4q+36qB_H^2+\frac{2q}{1-q}\Bigr]-2\ulaw h_0, \end{gather*} and \begin{align*} g^\iota_\ulaw&=\frac{2\mathfrak nm_\ulaw+C_\ulaw q}{rz^\iota_\ulaw h_-Z_-},\\ c^\iota_\ulaw&=\frac{2\ulaw r+\gamma c_0q +(2\mathfrak nm_\ulaw+C_\ulaw q)/h_-}{z^\iota_\ulaw Z_-},\\ A^\iota_\ulaw&=\frac{C_\ulaw+C_{\rm in,\ulaw}+910\gamma +2(1+\gamma)\mathfrak b/h_-}{z^\iota_\ulaw h_-Z_-},\qquad c^{+,\iota}_\ulaw=\frac{q(A^\iota_\ulaw)^2}{1-c^\iota_\ulaw}. \end{align*} Here $C_{\rm nn,\ulaw}$ bounds the $N_\Phi\otimes N_\Phi$ monomials, $C_{\rm sc,\ulaw}$ the selected-label coincidences, $C_{\rm cr,\ulaw}$ the other cross coincidences, and $C_{\rm in,\ulaw}$ the input-half coincidences. If $z^\iota_\ulaw>0$ and $c^\iota_\ulaw<1$, the cut operator $T^\iota_\ulaw$ of $\Gamma_{p,\ulaw}$ at $\iota$ on $L^2(\nu)$ satisfies \[ -g^\iota_\ulaw rI\preceq T^\iota_\ulaw\preceq(1+c^{+,\iota}_\ulaw q)I,\qquad \|P_0T^\iota_\ulaw\one\|\le qA^\iota_\ulaw,\qquad\|P_0T^\iota_\ulaw P_0\|\le c^\iota_\ulaw . \] The bounds at an endpoint hold for all larger primes with the same $\ulaw$, and $g^\iota_\ulaw\to\sqrt3+\sqrt7$. The block caps follow from \cref{lem:spec:tensorcomp}(b), as in \cref{prop:root-chamber}. \end{proposition} \begin{proof} Write $w_\ulaw=\frac13\sum_j\Upsilon_j$, with $\Upsilon_j=1+2\ulaw\Hs j+\gamma\Hs j^2$. It suffices to bound the soft operator of one polynomial $\Upsilon=1+2\ulaw\mathsf H+\gamma\mathsf H^2$ and then average and normalize. By \cref{lem:spec:cutkernel}(f), $T^\iota_\ulaw=(T^\iota_0\circ w_\ulaw)/\E_{\Gamma_{p,0}}w_\ulaw$. \emph{Soft expansion.} $\Phi\otimes\Phi=1\otimes1+N_\Phi\otimes1+1\otimes N_\Phi+N_\Phi\otimes N_\Phi$. The base term $(1\otimes1)\circ\Upsilon$ is positive semidefinite: $\mathsf H$ is a positive Gram kernel, so is its pointwise square, and the coefficients of $\Upsilon$ are nonnegative. In $(N_\Phi\otimes1)\circ\Upsilon$ the passive component carries the constant kernel and its selected labels; retaining the auxiliary variables, (L1) and (L2) give the absolute price $\mathfrak n[1+2\ulaw r+\gamma(1-q)]\le\mathfrak nm_\ulaw$ in both orders, and the other component the same. For the $63^2$ monomials of $N_\Phi\otimes N_\Phi$, (L3) with the multiplier $\Upsilon$ on four distinct selected labels, where $|\mathsf H|\le B_H$ (\cref{thm:weil}(b)) and $|\Upsilon|\le F_\ulaw$, gives $16F_\ulaw q$ each, together $C_{\rm nn,\ulaw}q$. The strict score mask is part of this multiplier; no other cross-injectivity mask is removed inside a norm. \emph{Coincidences.} The four single coincidences between the selected labels of the two halves have, before the input half is conditioned, total row and column mass at most $4q$, and there $|\mathsf H|\le2r$, so $|\Upsilon|\le1+4\ulaw r+4\gamma q$; the two equal-pair events have mass at most $2q^2$ and $\mathsf H=(1-2q)/r$, so $|\Upsilon|\le1+2\ulaw/r+\gamma/q$. They are deleted from the unmasked part $1+N_\Phi\otimes1+1\otimes N_\Phi$, whose kernel is pointwise at most $1+2\cdot63=127$ in absolute value ($N_\Phi$ being a sum of $63$ character monomials of modulus at most $1$), which costs $C_{\rm sc,\ulaw}q$. After these four, the coincidences across the cut are four twins and sixteen cross-component equalities, on which $|\Upsilon|\le F_\ulaw$, and (L4) gives $C_{\rm cr,\ulaw}q$. These are positive row and column bounds of the deleted kernels, not Schur monotonicity of signed kernels. \emph{Mass.} The raw mass of the uniform root is at least $Z_-$ (L4). Its scores have $|\E_{\Gamma_{p,0}}\Hs j|\le h_0$ and $\E_{\Gamma_{p,0}}\Hs j^2\ge1-4q-36qB_H^2-2q/(1-q)$ (\cref{lem:root-normalization}(b)); so $\E_{\Gamma_{p,0}}w_\ulaw\ge z^\iota_\ulaw$. \emph{Lower bound.} The restriction to $\nu$ costs $h_-^{-1}$ (\cref{lem:restriction}) and the normalization $Z_-^{-1}$ of the uniform root. Dividing by the tilt mass gives $T^\iota_\ulaw\succeq-g^\iota_\ulaw r$. \emph{Centred norm.} The selected pair of a half is a uniform distinct pair under $\nu$, by square-affine invariance and the interchange of the two components, so the centred base is at most $2\ulaw r+\gamma c_0q$: $P_0\mathsf HP_0=r\,\mathcal U\mathcal U^*$ with $\|\mathcal U\|\le1$, and \cref{cor:raw-pair-maps}(b) gives $\|P_0\mathsf H^2P_0\|\le c_0q$. The other terms are those of the lower bound, which gives $c^\iota_\ulaw$. \emph{Row.} On a six-distinct output half the unconditioned base row is constant, as $\mathsf H$ has mean $0$ and $\mathsf H^2$ has mean $(1-2q)^2+q^3$ when the other half is unconditioned. In a one-component term the linear row vanishes after the passive coordinate is integrated, and the square row multiplies $N_\Phi(x,x')$ by \[ \E_z\bigl[\chi(z-y)^2\chi(z-y')^2\chi(z-y'')^2\bigr]-\bigl(\E_z\chi(z-y)\chi(z-y')\chi(z-y'')\bigr)^2, \qquad y\ne y'', \] where $y,y''$ are the two selected labels of the output half and $y'$ that of the input half in the active component; this differs from one by at most $7q$, also when $y'\in\{y,y''\}$. With $|N_\Phi|\le65$ this costs $455q$. The two components therefore have row price $2(1+\gamma)\mathfrak bq/\sqrt h+910\gamma q$. The nine input-half coincidences and their pair spikes cost $C_{\rm in,\ulaw}q$, by the same ordinary/equal-pair split; all other errors cost $C_\ulaw q$. With $h^{-1/2}\le h_-^{-1}$, the half compression, the normalization of the uniform root and the tilt mass this gives $\|P_0T^\iota_\ulaw\one\|\le qA^\iota_\ulaw$. \emph{Upper bound.} $T^\iota_\ulaw$ is self-adjoint of mass one, so \cref{prop:matching:positive}(a) gives $T^\iota_\ulaw\preceq1+q^2(A^\iota_\ulaw)^2/(1-c^\iota_\ulaw)$. \emph{Uniformity.} After the explicit factor $r$ in $g^\iota_\ulaw$ is cancelled, all numerators are positive increasing in $q,r$ and all lower denominators positive decreasing, so evaluation at $q=1/P$, $r=P^{-1/2}$ is uniform for $p\ge P$. As $q\to0$, $\mathfrak n/r\to\kappa$ and $m_\ulaw$ and $z^\iota_\ulaw$ tend to $1+\gamma$, so $g^\iota_\ulaw\to2\kappa=\sqrt3+\sqrt7$. \end{proof} For $\gamma=1$, the individual squares at $\ulaw=1$, the proposition is the individual-square layer bound at that parameter; then $z^\iota_1=2-4q-36qB_H^2-2q/(1-q)-2h_0$, $2\mathfrak nm_1/r=2[\kappa(1+5r)+\mathfrak br](2+2r)$ and $F_1=(3+r)^2$. The proved coefficient tends to $2\kappa$ for every $\ulaw>0$, because the two one-component terms are priced separately; the larger layer cap costs only through the weight $v_{\rm L}$ of the completion (\cref{rem:middle-weights}). \paragraph{Sharper bounds for the tilted law (next nine subsections).} The following subsections sharpen the two cut bounds above at the seven interval starts. In order they: isolate collision terms on two explicit subspaces; give a finite gap for the uniform law; split a remainder across that gap; retain a constant term at the layer-flip cut; list supports for the $39$-trace law; extend it to all sorting cuts; use one parameter for both cuts; evaluate an explicit layer price; and evaluate a finite chamber price. A first reading can skip to \cref{subsec:positive-root-caps} and use the stated bounds. % Begin sections/20b_selected_refinements \subsection{Isolating collision terms on two explicit subspaces} \label{imp:local:protected-section} The remaining subsections of this section are finite calculations at one prime $p\equiv3\pmod4$, used only to evaluate the caps tabulated in \cref{subsec:positive-root-caps}. They do two things. First, they sharpen the collision part of the L20 bound for the uniform principal law, by computing it exactly on two explicit subspaces. Second, they construct and bound the coherent tilted law of the last interval $[2^{45},P_3)$: its score is an explicit linear combination of the trace functions $\E_s\prod_{i\in D}\chi(s-x_i)$ over a list of $39$ supports $D$ (subsets of the twelve label positions), symmetrised so that one law serves at every sorting cut. Its matrix bounds are first proved at the endpoint parameter $t_*=12/5$ and then transferred by convexity to the parameter $t=67/40$ used in the construction. In this part of the paper a support or a law is called \emph{physical} when it is described in the original twelve labels, as opposed to coordinates of a chosen half chart; a \emph{gate} is one finite matrix or positivity inequality checked exactly (\cref{app:certificates}). A reader who accepts the caps of \cref{cert:positive-root-caps} can skip to \cref{sec:middle-frame}. Local words in this part: a \emph{pin} is a label fixed by conditioning (core pins $C_i$, private pins $b_l$); a \emph{mask} is a subset of the edge set of the small graph under discussion, determining one character product; an \emph{arm} is one synthesis factor (feature map) in a product of two stars, and a \emph{free leaf} is a label coordinate occurring in no other factor; a \emph{spike} is an exceptional large value of a trace or score at special configurations (in particular at equal score pairs), always bounded separately; a \emph{hole term} is a term in which the common auxiliary label equals one of the fixed labels; an argument is \emph{rooted} when it keeps the common auxiliary summation label $s$ unintegrated, and \emph{unrooted} when $s$ is integrated out first; a star factor is \emph{passive} when it carries none of the displayed characters; the \emph{realification} of a complex feature space is the real span of the real and imaginary parts of its functions; an \emph{endpoint} $X$ is the lower endpoint of an interval, at which bounds are evaluated; and \emph{physical} (as defined above) is opposed to \emph{soft}: the physical kernel is the actual kernel $K_0$ in the original labels, the soft kernel its expansion without distinctness. We begin with the uniform law, before any tilt. The collision part of its L20 kernel---the terms where labels of the two halves coincide---is split according as the test function lies in one of two explicit subspaces or in their orthogonal complement; on the two subspaces it is computed exactly below. In the following local calculations write $A=\mathsf R$, $a=\mathfrak r$ for the rectangle and its private mean in \cref{prop:l20-rectangular}, $C_0=A-a\otimes1$, and $Z=\boldsymbol z$, with the other normalized star features $v,w,e$ as in \cref{prop:l20-rank4}. All spaces have probability normalization, $q=p^{-1}$ and $r=\sqrt q$. The letter $a$ in these local formulas denotes a function on the core; the scalar exponent does not enter this calculation. Likewise $t$ below denotes the root parameter $\ulaw$, not scalar repricing. Write $Q=I-J$ for ordinary centering (subtracting the mean). Put $a_2=\|a\|_2$, $P_a=aa^*/a_2^2$ and \[ P_{\rm c}=I_{\rm core}\otimes J_{\rm pair},\qquad P_{\rm p}=P_a\otimes Q_{\rm pair},\qquad P=P_{\rm c}+P_{\rm p},\qquad R=Q_a\otimes Q_{\rm pair}. \] The core labels are $C=(a_0,a_1,c_0,c_1)=(C_0,C_1,C_2,C_3)$, with $a_i\to c_j$, and the private pair is $b=(b_0,b_1)$. Set \[ K_C(s)=\prod_i(1-\chi(s-a_i))\prod_j(1+\chi(s-c_j)), \qquad\kappa_C=\E_sK_C(s),\qquad Z_C=(K_C-\kappa_C)/(\sqrt{15}r). \] The six-distinct induced half is obtained by conditioning the independent core and distinct private pair on the six labels being pairwise distinct. \begin{lemma}[Compression of the constant kernels at pinned labels] \label{imp:local:pin-projections} For $h\in H=L^2_0(\mathbb F_p)$, let $\sigma=(-1,-1,1,1)$, $V_i h=h(C_i)$, $B_lh=h(b_l)$, $w=\sum_iV_i/2$, $u=(V_0+V_1-V_2-V_3)/2$, $v=(B_0+B_1)/\sqrt2$, and \[ W h(b)=\mathbb E_s\chi(s-b_0)\chi(s-b_1)h(s),\quad e=W/r, \quad R_lh(b)=\mathbb E_s\chi(b_l-s)h(s). \] On $H$, for $\epsilon\in\{-1,1\}$, define \[ F_i^\epsilon h=\prod_{l=0}^1(1+\epsilon\chi(b_l-C_i))h(C_i), \qquad G_lh=K_C(b_l)h(b_l), \] and set $k=\mathbb E a/a_2$, $k'=\mathbb E(a\kappa)/a_2$, where $\kappa$ denotes the function $C\mapsto\kappa_C$ and the expectations are under the core law (uniform on core configurations). The sixteen core-pin constant kernels and the four private-pin constant kernels have auxiliary-mean-zero parts \[ K_c=q\sum_{i,j}F_i^{\sigma_j}(F_j^{\sigma_i})^*, \qquad K_b=q(G_0+G_1)(G_0+G_1)^*. \] Their protected blocks are \begin{equation}\label{eq:merge-local-I-14} \begin{array}{c|c|c|c} &P_{\rm c}KP_{\rm c}&P_{\rm p}KP_{\rm p}&P_{\rm c}KP_{\rm p}\\ \hline K_c&4q(1-q)^2ww^*&16q^2k^2ee^* &4q(1-q)k[-2u(R_0+R_1)^*+2wW^*]\\ K_b&60q^2ZZ^*&2q(k')^2vv^*&2\sqrt{30}qrk'Zv^* \end{array} \end{equation} The full auxiliary constant-label pieces contribute, respectively, $16q(1-q)^2J$ and $4q\kappa\otimes\kappa$ on $P_{\rm c}$, and zero other protected blocks. \end{lemma} \begin{proof} Uniformity of the private pair and affine invariance of the actual core give exactly \[ P_{\rm c}F_i^\epsilon=(1-q)V_i,\quad P_{\rm p}F_i^\epsilon=k[\epsilon(R_0+R_1)+W],\quad P_{\rm c}G_l=\sqrt{15}rZ,\quad P_{\rm p}G_l=k'B_l. \] Indeed $\mathbb E[a\mid C_i=s]=\mathbb E a$ and $\mathbb E_C[aK_C(s)]=\mathbb E(a\kappa)$, independently of $s$. Summing uses $\sum\sigma_i=0$, $\sum V_i=2w$, and $\sum\sigma_iV_i=-2u$, proving \eqref{eq:merge-local-I-14}. On the constant label, $P_{\rm c}F_i^\epsilon1=(1-q)1$, $P_{\rm p}F_i^\epsilon1=0$, $P_{\rm c}G_l1=\kappa$, and $P_{\rm p}G_l1=0$, which proves the last assertion. \end{proof} \subsection{A finite collision bound for the uniform law} \label{imp:local:finite-collision-section} This result is a finite bound for the uniform (untilted) L20 root in the original twelve labels. Its positive coefficient, marginal range, variance and layer data are consequently unchanged. Retain the independent-half rectangle $A=a\otimes1+C_0$ and the certified bounds for the rectangle and its domain gap from \cref{prop:l20-rectangular} and \cref{prop:l20-pair-gap}: numbers again called $a_2,c$ with $a_2\ge\|a\|_2$, $c\ge\|C_0\|$, $z_2\ge\|Z\|^2$ (here $a_2,c$ are upper bounds, although the same letters denoted the exact norms above). Put \[ \theta=(1-q)(1-3q)(1-7q),\quad h_-=(1-4q)(1-5q), \quad \eta=11r+2q, \] \begin{equation}\label{eq:merge-local-I-15} \begin{aligned} d_\kappa&=\sqrt{\frac{5q+34qr+11q^3}{\theta}}+2q,\qquad d_a=\frac{(2+\eta+16q)d_\kappa+15q}{1-q},\\ a_-&=(1-\eta)(1-\eta-16q),\qquad \omega=d_a/a_-. \end{aligned} \end{equation} From the rectangle estimates of \cref{sec:middle-reference} we retain the bounds $|\kappa-1|\le\eta$, $\|a-1\|_2\le d_a$ and $a\ge a_-$. \begin{proposition}[Finite bound for the collision term on the two protected subspaces] \label{imp:local:collision-gap} Define \[ \delta_c=\frac{4(4r+92q)}{\sqrt{\theta(1-q)}}, \qquad \delta_b=\frac{4\sqrt{15}\,r}{\sqrt{\theta(1-q)}}, \] \begin{equation}\label{eq:merge-local-I-16} E_{\rm pin}=256q(2\delta_c+\delta_c^2) +1024q(2\delta_b+\delta_b^2),\qquad E_{\rm mult}=\frac{24903680q^2}{1-q}, \end{equation} and \begin{equation}\label{eq:merge-local-I-17} \begin{aligned} b_B&=64q(2+\eta),\\ A_0&=4q+60q^2z_2,\qquad A_1=2q(1+\eta)^2+16q^2,\\ X&=8qr\bigl(\sqrt{2/(1-q)}+1\bigr) +2\sqrt{30}qr(1+\eta)\sqrt{z_2},\\ \alpha&=\max(A_0,A_1)+X+16q\omega^2+4q(\eta+\omega)^2,\\ E_S&=\frac{b_B^2}{a_-^2-b_B},\qquad G=a_2c+\alpha,\qquad D=c^2+b_B . \end{aligned} \end{equation} For $p\equiv3\pmod4$ satisfying $a_-^2>b_B$ and $G>D$, the old mass-one root operator on its fixed induced half satisfies \begin{equation}\label{eq:merge-local-I-18} T_{\rm old}\succeq-g_{\rm pin}rI,\qquad g_{\rm pin}= \frac{E_S+G+b_B^2/(G-D)+E_{\rm pin}+E_{\rm mult}} {h_-(1-\varepsilon_Z)r}. \end{equation} Here $\varepsilon_Z$ is the normalizer error of the uniform (untilted) law from \cref{prop:l20-completion}. Exact rational endpoint evaluation is valid uniformly for every prime above the endpoint. For example, the endpoint $19951586$ gives $g_{\rm pin}<5.481634404$, compared with the retained $5.500057067029$. \end{proposition} \begin{proof} Let $B$ be the sum of the twenty full-label constant pin-incidence kernels in Lemma~\ref{imp:local:pin-projections}. For a core pin $C_i=C'_j=t$, where $C'$ denotes the core labels of the second half, its incident factors are two half multipliers bounded by four. After removing them, the cross polynomial is a swapped product of two $3$-by-$2$ rectangles. Given one core coordinate, the remaining three have density $16/\theta$ relative to the three-label cube; the private distinct-pair density is $1/(1-q)$. The six-edge rectangle has seventeen nonempty stars and forty-six other masks (edge subsets that are not stars). Group the stars on the full independent cube. Every raw star has norm at most $r$, because its Gram is a Schur product of Paley Grams with diagonal at most one and norm at most $q$. Distinct output supports are orthogonal ANOVA spaces. On nonzero translation sectors, the three singleton and four higher output supports, and the two singleton and one pair input supports, give a seven-by-three matrix. Collapsing the two equal singleton columns gives Gram \[ \begin{pmatrix}14&\pm i\sqrt2\\\mp i\sqrt2&3\end{pmatrix}, \] whose largest eigenvalue is below sixteen: the three retained core signs sum to $\pm1$. On zero translation frequency the blocks are $2\sum_{|S|\ge2}\sigma_Sm_S\otimes1$, of norm at most $4r$, and $3\,1\otimes m_{\rm pair}$, of norm at most $3r$. Their input and output spaces are orthogonal. This retains the full auxiliary constant sector and proves that the seventeen stars together have norm at most $4r$. Every other mask contains two disjoint edges whose induced subkernel is a matching, a path, or a restricted $K_{2,2}$, of norm at most $2q$. Fixing the third output coordinate inserts only one-variable input multipliers and separate output exclusions. Distinctness of the selected input and output pairs stays inside the restricted kernel. Density congruence gives $\|A_i-J\|\le\delta_c$. For a private pin the two incident factors are bounded by sixteen. The remaining rectangle is $K_C(s)$ with $s$ uniform outside the pinned label. Its fifteen nonempty output supports are orthogonal on the full four-label cube, giving norm $\sqrt{15}r$ before the same density congruence. Its defect from $J$ is at most $\delta_b$. A swapped product of two $J+$defect rectangles differs from $J$ by at most $2\delta+\delta^2$. Equality of two uniform coordinates disintegrates exactly as $q\mathbb E_t$; conditional Cauchy--Schwarz recovers the original half norms. The sixteen core pins and four private pins therefore give $\|D_{\rm sum}-B\|\le E_{\rm pin}$, where $D_{\rm sum}$ is the sum of those twenty pin terms, with multipliers $16\cdot4^2$ and $4\cdot16^2$. The condition that the labels involved are distinct is retained inside every norm estimated above. The sixteen core/private equalities vanish because $K_C$ is zero at every core label. Of the other twenty events, compatible double equalities form matchings on two six-distinct halves. Every two-coordinate input marginal has point mass at most $2q^2/(1-q)$: this is attained by a directed core pair; same-side and private pairs have mass $q^2/(1-q)$, and core/private pairs have mass $q^2$. The soft density is at most $65536$. For multiplicity $m$, $m-1\le\binom m2$. Counting even all $\binom{20}{2}=190$ pairs bounds the positive overlap correction by $E_{\rm mult}$. Conditioning on the input half contributes the single factor $h_-^{-1}$ in \eqref{eq:merge-local-I-18}, which also covers every higher coincidence. With $f_\epsilon(s)=\prod_l(1+\epsilon\chi(b_l-s))$ the private factor in $F_i^\epsilon$, the exact second moment $\mathbb E f_\epsilon^2=4(1-2q)$ gives $\|F_i^\epsilon\|^2=4(1-2q)$, while $\|G_l\|^2=16\mathbb E\kappa\le16(1+\eta)$. Hence $\|B\|\le b_B$. In \eqref{eq:merge-local-I-14}, use $\|w\|,\|v\|,\|e\|\le1$, $\|u\|\le(1-q)^{-1/2}$, $k\le1$ and $k'\le1+\eta$. The nonconstant protected blocks are bounded by $A_0,A_1,X$. On the core space orthogonal to $a$, the constant-label blocks cost at most $16q\omega^2$ and $4q(\eta+\omega)^2$. Thus $P_-BP_-$ (with $P_-$ as defined in the next paragraph) has norm at most $\alpha$; no auxiliary constant mode is omitted. Let $S=\operatorname{span}(a\otimes1)$ and $P_-=P\ominus S$. The old rectangle reduces $S$, $P_-$ and $R$. Its lower diagonal bounds are $\|a\|_2^2$, $-\|a\|_2\|C_0\|$, and $-\|C_0\|^2$. After subtracting $B$, the $S$ block is at least $a_-^2-b_B$; its off-diagonal norm is at most $b_B$. The positive-block elimination in \cref{lem:block-completion}(a) costs at most $E_S$ times the remaining identity. The other two blocks have lower bounds $-G,-D$ and off-diagonal norm at most $b_B$. Since $G>D$, \cref{lem:block-completion}(b) gives their lower bound $-G-b_B^2/(G-D)$. Adding the two pin errors, compressing to the physical half and dividing by the old normalizer proves \eqref{eq:merge-local-I-18}. For uniform endpoint evaluation, retain certified endpoint upper bounds on $a_2,c/r,z_2,\varepsilon_Z$. All normalized numerators are positive increasing in $q,r$, and the lower denominators are positive decreasing on the gates. Before the last Schur step replace $G/r,D/r,b_B/r$ by endpoint majorants $G_0,D_0,B_0$. The lower block matrix with these fixed entries is valid at every larger prime; use $G_0+B_0^2/(G_0-D_0)$ after checking $G_0>D_0$. No monotonicity of a moving gap denominator is assumed. \end{proof} \subsection{Allocating the pair-square remainder across a spectral gap} \label{imp:env:gap-section} All spaces in this subsection carry probability measures; its $C$ is the rectangle $C_0$ above. Let $U$ be the uniform directed $K_{2,2}$ core, with ordered side pairs $a(u),c(u)$, and let $V$ be the uniform ordered distinct-pair space. Put \begin{align*} A(u;b)&=K_u(b_0)K_u(b_1),\quad a=A1,\quad C=A-a\otimes1,\\ a_2&=\|a\|_2,\quad a_\infty=\|a\|_\infty,\quad c=\|C\|. \end{align*} Here $K_u$ is the function $K_C$ above with core $C=u$. The rectangle identities used in Proposition~\ref{prop:root-chamber} give $C1=C^*1=C^*a=0$. Write $M^2=\sup_u\int|C(u;b)|^2\,db$; the exact row square $256a(u)-a(u)^2$ permits $M^2\le256a_\infty$. The column square is constant. Indeed square-affine changes and private-pair exchange act transitively on $V$ and preserve $C$. If $F_a,F_c:L^2(V)\to L^2(U)$ are the side-pair pullbacks, the same symmetry proves \begin{equation}\label{imp:env:conditional-square} F_a^*M_{a^2}F_a=F_c^*M_{a^2}F_c=a_2^2I. \end{equation} For real kernels $X,Y:V\to U$, define \[ T[X,Y]((u,b),(u',b'))=X(u;b')Y(u';b). \] Set \[ P_{\rm c}=I_U\otimes J_V,\quad P_{\rm p}=P_a\otimes Q_V,\quad P=P_{\rm c}+P_{\rm p},\quad R=Q_a\otimes Q_V,\quad P_a=aa^*/a_2^2. \] Put $K=T[A,A]$; expanding $A=a\otimes1+C$ shows that $P,R$ reduce $K$ exactly. The $R$ block is $T[C,C]$, of norm at most $c^2$. On $P$, the positive rank-one term $aa^*\otimes J$ and the two adjoint blocks $a_2C,C^*a_2$ give a lower bound $-a_2c$. \begin{lemma}[The pair-square residual] \label{imp:env:pair-residual} Put $q=p^{-1}$, $r=\sqrt q$, and $H(b,d)=r^{-1}\mathbb E_s\chi(s-b_0)\chi(s-b_1) \chi(s-d_0)\chi(s-d_1)$. Then \begin{align*} \sigma&=(1-2q)^2+\frac{q(1-3q)^2}{1-q},\qquad L=H^{\circ2}-\sigma J,\\ 0&\preceq L\preceq\rho I,\quad L1=0, \quad\rho=q\left(\frac4{1-q}+2q\right). \end{align*} For \begin{align*} E_c&=\tfrac12K\circ\{L(a(u),c(u'))+L(c(u),a(u'))\},\\ E_b&=K\circ L(b,b'),\qquad E=(2E_c+E_b)/3, \end{align*} one has \[ PEP\succeq-\alpha P,\quad\|REP\|\le b,\quad \|RER\|\le\gamma, \] where \[ \alpha=\frac{2\rho}{3}\max(a_2^2,c^2),\quad \gamma=\rho M^2,\quad b=\frac{\rho M}{3} \sqrt{(2a_2+c)^2+(a_2+2a_\infty c/a_2)^2}. \] The separate $R\leftarrow P_{\rm c}$ bound (the norm of the block $REP_{\rm c}$) is $b_0=\rho M(2a_2+c)/3$. \end{lemma} \begin{proof} For the raw pair map $W$ with kernel $\chi(s-b_0)\chi(s-b_1)$, the exact Paley Gram is $W^*W=qg_eQ+q^2J$, where $g_e=(1-2q-q^2)/(1-q)$. This gives the constant row sum $\sigma=(1-q)g_e^2+q^3$. The auxiliary constant diagonal contributes $(1-2q)^2J$ to $H^{\circ2}$; the part of $H^{\circ2}$ orthogonal to that contribution is positive with norm at most $\rho$, by the distinct-pair $K_{2,2}$ bound and the mean-zero diagonal bound. Removing its constant eigenvalue proves the asserted bounds on $L$. Consider first the unaveraged core placement $L(a(u),c(u'))$. Its rank/rank term (the part $a\otimes1$ in both factors; the rank/centered and centered/centered terms below are analogous) is supported on $P_{\rm c}$ and costs at most $\rho a_2^2$, by \eqref{imp:env:conditional-square}. The rank/centered terms have zero $P$ compression: use $C1=0$ on $P_{\rm c}$, and \eqref{imp:env:conditional-square} followed by $L1=0$ on $P_{\rm p}$. Their $R\leftrightarrow P_{\rm c}$ norm is at most $a_2\rho M$. To see the normalization explicitly, their squared Gram is bounded by $a_2^2\rho^2(CC^*)\circ(F_aF_a^*)$; the last operator is a direct integral over pair fibers, each with trace at most $M^2$. The centered/centered term kills $P_{\rm c}$. Its $P_{\rm p}$ compression is $B_a^*LB_c/a_2^2$, where $M_a$ is multiplication by the function $a$, $B_a=F_a^*M_aC$, and $B_c=F_c^*M_aC$. Equation~\eqref{imp:env:conditional-square} gives $\|B_a\|,\|B_c\|\le a_2c$, so this compression costs $\rho c^2$. The full image of $a\otimes g/a_2$ is \[ (Cg)(u)(LF_c^*M_aC)(a(u);b)/a_2. \] The second factor has constant squared row norm, at most $\rho^2a_\infty^2M^2$, giving the $R\leftarrow P_{\rm p}$ bound $\rho a_\infty Mc/a_2$. Factoring $L$ into two square roots, retaining the same auxiliary label in the two product maps and the private-coordinate swap, gives the whole centered/centered norm at most $\rho M^2$. For the private placement, the rank/rank term is $aa^*\otimes L$ and is positive on $P_{\rm p}$. The rank/centered term couples $P_{\rm p},R$ with norm at most $a_2\rho M$: its squared Gram is bounded by $\rho^2(C^*C)\circ I$, whose diagonal is the constant column square. The centered/centered term kills $P_{\rm p}$, has positive $P_{\rm c}$ compression $CLC^*$, and has $R\leftarrow P_{\rm c}$ norm at most $\rho Mc$. The same square-root factorization bounds its full norm by $\rho M^2$. Thus the two columns of $REP$ cost respectively $\rho M(2a_2+c)/3$ and $\rho M(a_2+2a_\infty c/a_2)/3$. Their squared sum proves the result. These are product-operator bounds, not an arbitrary-kernel Schur-multiplier assertion. \end{proof} \begin{proposition}[Finite chamber-cut price for the pair-square law, with the gap bound] \label{imp:env:finite-gap-chamber} Use the retained finite constants of Proposition~\ref{prop:root-chamber}. In its notation (the following ten aliases are used only in this proposition; in particular $N,\Gamma,h,\varepsilon,e$ do not have their earlier meanings here), $N=N_A$, $\Gamma=\Gamma_{20}$, $E_L=\eps_{\rm lin}$, $\ell_0=\mathfrak l_0$, $h=h'_p$, $D_{\rm old}=D_{\rm bal}$, $P_{\rm spike}=\mathfrak s$, $\varepsilon=\eps_Z$, $h_{\rm mean}=h_0$ and $e=\eps_{\rm sq}$. Use $a_-\le a$, $a_+\ge\|a\|_\infty$, $d\ge\|a-1\|_2$, $\delta=d/\sqrt{1-q}$, and \[ \|QL_{\rm soft}Q-rM_{\rm pair}\|\le E_L,\qquad \|QL_{\rm soft}1\|\le\ell_0r+E_L, \] where $L_{\rm soft}=K\circ\Hbar$ is the soft kernel multiplied by the mean score and $M_{\rm pair}$ the leading pair matrix of \cref{prop:root-chamber}. Let $c$ be an upper bound for $\|C\|$, namely the retained rectangular-domain-gap bound, and assume $c\sqrt{26}$ of $3g^3+\Lambda g^2-90g-26\Lambda=0$ (the cubic is negative at $\sqrt{26}$ and strictly increasing beyond it). Define \begin{align*} G&=(s_+-k)a_2c+k\{g(\Lambda)r\Gamma+E_{0P}\} +2tE_{\rm rank}+\tfrac{4t}{3}rc^2+t^2\alpha,\\ d_L&=E_L+rd_a^2/3+qrc^2,\\ b_L&=E_L+rd_a/3+d_a(\ell_0r+E_L),\\ h_L&=\ell_0r+E_L(1+d_a),\\ D&=s_+c^2+2td_L+t^2\gamma+ \frac{(2th_L+t^2b_0)^2}{s_-a_-^2}, \qquad B=2tb_L+t^2b. \end{align*} Here the residual constants are those of Lemma~\ref{imp:env:pair-residual}, with $M=16\sqrt{a_+}$ and $a_2$ in denominators replaced by the smaller bound $a_-$, which only enlarges the constants. If $G>D$, the independent-half weighted rectangle satisfies \[ K\circ\frac13\sum_{j=0}^2(1+t\Hs j)^2 \succeq-\left(G+\frac{B^2}{G-D}\right)I. \] For the actual normalized root, the following number $g$ is valid in the bound $T\succeq-grI$ for its chamber operator $T$ in the fixed half chart (a \emph{full fixed-half negative coefficient}): \begin{equation}\label{imp:env:physical-gap} \begin{gathered} \frac{h^{-1}[G+B^2/(G-D)]+C_w}{(1-\varepsilon)zr},\\ C_w=(1+2tB_H+t^2B_H^2)D_{\rm old} +\left(\frac{2t}{hr}+\frac{t^2}{hq}\right)P_{\rm spike}. \end{gathered} \end{equation} Here $B_H=2+r$, $h$, $D_{\rm old}$, $P_{\rm spike}$, $\varepsilon$, and $z=1+t^2-2t h_{\rm mean}-t^2e$ are the retained conditioning, collision, spike, normalizer and moment bounds. The upper bounds for the norm, variance and range of that same law at the same parameter, proved in \cref{prop:root-chamber}, remain valid. \end{proposition} \begin{proof} Let $S$ project onto $(a/a_2)\otimes1$, and set $P_-=P-S$. The exact scalar pair mean is $qr$. With $L_0=K\circ\frac13\sum_j(H_j-qr)$, the weighted rectangle is $sK+2tL_0+t^2E$, where $s=1+2tqr+t^2\sigma\in[s_-,s_+]$. Conditional identity \eqref{imp:env:conditional-square} and the centered pair kernels imply $SL_0S=SES=SL_0P_-=SEP_-=0$. The positive $S$ block is therefore $sa_2^2$. On $P_-$, the exact old bound is $-a_2c$. In comparing $K$ with its leading stars, $T[C,C]$ has zero $P$ compression, so only the rank/centered remainder $E_{0P}$ is charged. The inherited eighteen-feature Gram bound $\Gamma$ also applies on the independent half: cross-factor Grams vanish, and within-core and within-private conditional counts dominate the smaller counts used in its original proof. The finite leading matrix has negative norm $g(\Lambda)$; its remaining blocks cost at most $\max(2,\Lambda/3)\le5D_0$. Use $G_0+B_0^2/(G_0-D_0)$ at every larger prime. All constituent normalized numerators increase in $q,r$, and all positive lower denominators decrease. This order of operations avoids assuming monotonicity of a quotient with a moving gap. The fixed $\Lambda$ remains feasible: at the endpoint $X$ (the lower endpoint of the interval) $k\le s_-(X)$, and $s_-(p)$ is nondecreasing in $p$, so $k\le s_-(p)$ for all $p\ge X$. \end{proof} \begin{corollary}[Interpolation after physical normalization] \label{imp:env:physical-interpolation} Let $g_0r$ be any full negative price for the mass-one unchanged physical root $\Gamma_0$. Fix $0<\tau\le1$. In Proposition~\ref{imp:env:finite-gap-chamber}, replace \[ s_+=\tau+t^2+2tqr,\qquad s_-=\tau+t^2(1-4q), \] and replace the constant $1$ in the collision coefficient $1+2tB_H+t^2B_H^2$ by $\tau$. Keep all linear and square coefficients $2t,t^2$, and check the same positive-block and gap conditions. After these replacements, choose endpoint majorants $G_0,D_0,B_0$ for $G/r,D/r,B/r$, respectively, with $G_0>D_0$, as in the final paragraph of the proposition's proof, and set \[ C_{\rm soft}=G_0+\frac{B_0^2}{G_0-D_0}. \] This is the raw soft coefficient, before half-conditioning, scalar normalization and collision corrections. If $C_{w,\tau}$ is the corresponding collision price in \eqref{imp:env:physical-gap}, then \[ g_{\rm int}= \frac{(1-\tau)g_0+ [C_{\rm soft}/h+C_{w,\tau}/r]/(1-\varepsilon)}{z} \] is a full negative coefficient, in the sense above ($T\succeq-g_{\rm int}rI$), for the original individual-square (pair-score) law. Here $h$, $\varepsilon$ and $z$ are those of the proposition at the same $t$. Its marginal and layer data remain those at the original parameter $t$. \end{corollary} \begin{proof} Before normalizing the new tilt, split its exact physical operator as \[ (1-\tau)\Gamma_0+ \Gamma_0\left(\tau+2t\,\frac13\sum_jH_j +t^2\,\frac13\sum_jH_j^2\right). \] The first summand has lower price $(1-\tau)g_0r$ in the mass-one physical convention. The second summand can have signed entries; the three-block argument requires only its positive $S$ block and the stated gap gates. Its raw scalar normalization alone costs $(1-\varepsilon)^{-1}$. Absolute collision weights are bounded by $\tau+2tB_H+t^2B_H^2$, with the same exceptional-pair terms. Add these two lower prices and divide once by the common new mass lower bound $z$. No second old-normalizer or half-conditioning factor belongs to the first summand. \end{proof} \subsection{Retaining the constant coefficient at the layer cut} \label{imp:env:layer-section} \begin{proposition}[Layer-cut remainder, summed without expanding all monomials] \label{imp:env:layer-resummation} For the individual-square law in Proposition~\ref{prop:root-layer}, put \begin{align*} d_\mu&=\frac8{1-q^2},\quad M_\Phi=d_\mu(1+q)^3, \quad b_*=6+51d_\mu,\\ n&=r\{\kappa(1+5r)+b_*r\},\quad \kappa=(\sqrt3+\sqrt7)/2,\quad B_H=2+r. \end{align*} Replace its remainder coefficients by \begin{align*} C_{\rm nn}&=(n/r)^2+3969\cdot16(2tB_H+t^2B_H^2),\\ C_0&=128M_\Phi+8d_\mu^2(1+q)^5,\\ C_{\rm sc}&=C_0+127(20tr+16t^2q+2t^2). \end{align*} Keep $C_{\rm cr},C_{\rm in}$ and both mass lower bounds unchanged, and substitute $C_{\rm nn}+C_{\rm sc}+C_{\rm cr}$ in its negative, centered and marginal formulas. The resulting prices hold for the same positive law, with no change to its support or parameter. \end{proposition} \begin{proof} Write the probability-normalized triangle operator of \cref{prop:root-layer} as $\Phi=J+N$, where $\|N\|\le n$. In the score-independent coefficient retain the full $N\otimes N$, of norm at most $n^2$, instead of expanding its $63^2$ nonempty monomials. The score-containing terms retain their specified four-label mask, with all labels distinct, and the two-Paley price, giving $C_{\rm nn}$. Delete the removed constant mask from the whole positive $\Phi_1\Phi_2$ of the two triangle operators. Among its four specified equalities, two twins cost $64M_\Phi q$ each and two cross-component pins cost $4d_\mu^2(1+q)^5q$ each. Their positive union bound gives $C_0$, including all intersections. For terms containing a score, single coincidences in the specified single strata have $|H|\le2r$ for the pair score $H$ of \cref{def:positive-root}, and equal unordered pairs have $|H|\le1/r$; the unchanged mass bounds $4q,2q^2$ and absolute base density $127$ give the remaining terms of $C_{\rm sc}$. In particular no mask is deleted through a signed $N\otimes N$ kernel. Its row contribution is bounded by its full norm, so the same replacement is valid in the marginal estimate. The input-half conditioning factor from \cref{prop:root-layer} remains an upper bound here. The saving in the remainder coefficient is exactly \[ 3969\cdot16-(n/r)^2+127(4+2q)-C_0, \] whose limit is $62476-\kappa^2>62471$. After cancellation of $r$, every displayed endpoint expression has positive increasing numerators and decreasing positive lower denominators. The explicit mass, centered-gap and tensor-domain gates (\cref{app:certificates}) therefore certify uniform prices above the endpoint. They must still be combined with a chamber price for the same $t$, fresh native completion, and the corresponding marginal restoration. \end{proof} \subsection{Supports of the \texorpdfstring{$39$}{39}-trace law} The tilted law of the last interval has weight $\eta+(1+tH)^2$, where each trace in $H$ uses the same auxiliary summation label on its two halves. Squaring introduces two auxiliary labels; their diagonal must be retained. The following lemma bounds the product synthesis on one half, including this diagonal, before it is contracted with the other half. \begin{lemma}[Higher-star products] \label{imp:local:star-product} Let $H=L^2_0(\mathbb F_p)$ and $U_S=(\psi_S-\mathbb E\psi_S)/r:H\to L^2(C)$, where $\psi_S(s)=\prod_{i\in S}\chi(s-C_i)$. For subsets $S,T$ of the four core coordinates with $S$ nonempty and $|T|\ge2$, let $U_S\cdot U_T:H\otimes H\to L^2(C)$ be the pointwise product synthesis, defined on simple tensors by $(U_S\cdot U_T)(f\otimes g)=(U_Sf)(U_Tg)$. It has the decomposition \begin{equation}\label{eq:merge-local-I-4} \begin{aligned} U_S\cdot U_T&=h e_0^*+R,\quad Re_0=0,\quad \|R\|=O(1),\\ h&=1_{S=T}/r+O(1)\ \text{pointwise},\qquad e_0(s,u)=\frac{p1_{s=u}-1}{\sqrt{p-1}}. \end{aligned} \end{equation} Here $h$ is a function on core configurations and the $O(1)$ constants are absolute, uniformly in $p$ and in the labels. The same conclusion holds for fixed linear combinations, with the coefficient of $1/r$ equal to their coefficient-vector inner product. A coordinate evaluation times a higher star has product norm bounded by an absolute constant. The assertion does not include a shared singleton--singleton support. \end{lemma} \begin{proof} For $Df(s,u)=\sqrt p1_{s=u}f(s)$, its projection $D_H$ to $H\otimes H$ obeys \begin{equation}\label{eq:merge-local-I-5} D_H^*D_H=(1-2q)P_H+(1-q)J. \end{equation} On the orthogonal complement of its range, auxiliary functions vanish on $s=u$ and all auxiliary centering terms disappear. If $S\ne T$, choose two output coordinates whose incidence with $s,u$ is a matching or a three-edge path. Such coordinates exist also when one support contains the other. Two Paley transforms give norm $q$, with a bounded middle multiplication for the path. If $S=T$, choose two common coordinates and use the restricted $K_{2,2}$ estimate $2q$, retaining distinctness of both output and auxiliary pairs. After fixing all other core coordinates, their characters are bounded auxiliary multipliers. Exclusions of fixed coordinates are separate output restrictions. The actual core density is $16/\theta$, $\theta=(1-q)(1-3q)(1-7q)$, so output compression costs at most $4/\sqrt\theta$. Division by $r^2=q$ proves the off-diagonal bound without deleting a coupled injectivity mask. On the mean-zero part of $D_H$, repeated-root cancellation gives $U_{S\triangle T}$, or zero if $S\triangle T$ is empty, plus at most four evaluation terms of size $q/r=r$. Terms containing an auxiliary mean are bounded by the degree-four character estimate (\cref{thm:weil}). Equation \eqref{eq:merge-local-I-5} gives a bounded diagonal inverse. Finally the $e_0$ image is \[ \frac{\mathbb E_s[(\psi_S-m_S)(\psi_T-m_T)]} {r\sqrt{1-q}},\qquad m_S=\mathbb E_s\psi_S. \] Its numerator is $1+O(q)$ when $S=T$ and $O(r)$ otherwise. For evaluation times a higher star, fix the evaluated coordinate; one other leaf supplies a Paley factor $r$, canceling the star's normalization. Passing from the product law to the actual law changes the bound only by the density factor $\prod_jD_j$ of \cref{lem:l20-star-matrix}, an absolute constant. \end{proof} \subsection{The \texorpdfstring{$39$}{39}-trace law at every sorting cut} \label{imp:local:filtered-coherent} We now define the list of supports. A symmetrised list $\mathcal D_{51}$ of $51$ supports is defined first, and the action of its score and of its square on the soft kernel (the kernel without the distinctness indicator) is computed, keeping every mean term of a star, including the functions invariant under simultaneous translation of all labels. Removing the twelve supports with fewer than three labels in one layer then leaves the list $\mathcal D_{39}$ used in the law, and explicit finite matrix bounds at the endpoint parameter $t_*=12/5$ follow. The twelve vertices are grouped into six bases, numbered $0,\ldots,5$, each carrying two labels $(j,\ell)$, $\ell\in\{0,1\}$, in the two layers (the ``twins'' $(j,0),(j,1)$). The directed edges between the bases are \begin{equation}\label{eq:merge-local-I-19} 0\longrightarrow2\longrightarrow4\longrightarrow0,\qquad 1\longrightarrow5\longrightarrow3\longrightarrow1. \end{equation} At the first chamber cut, with the two halves identified by the reflection (the reflected chart), the halves are $(a,b,c)=(0,1,2)$ and $(a',b',c')=(5,4,3)$. On each four-label core retain the four cubic supports and the quartic support. Give a support $S$ sign $(-1)^{|S\cap a|}$. Form the twenty-five products of pairs of supports, one from each core, divide their coefficients by five, and average over \begin{equation}\label{eq:merge-local-I-20} j\mapsto j,\ j+2,\ j+4,\ 1-j,\ 3-j,\ 5-j\pmod6. \end{equation} After collecting equal physical supports this gives seventy-five nonzero coefficients, each $\pm1/15$. Retain a support if, at every chamber cut, either its intersections with the core labels of both halves have size at least two, or its intersections with the private labels of both halves have size two. Denote this fifty-one-element dictionary by $\mathcal D_{51}$, retaining the collected coefficients $c_D$. Put \begin{equation}\label{eq:merge-local-I-21} H_{\mathcal D} =\frac1r\sum_{D\in\mathcal D}c_D\, \mathbb E_s\prod_{i\in D}\chi(s-x_i), \qquad \sigma_{\mathcal D}=\sum_D c_D^2 . \end{equation} Here $x=(x_i)$ is the configuration of the twelve labels. This definition uses physical labels and is independent of a chosen cut. In particular $\sigma_{51}=17/75$ and $\sum|c_D|=17/5$. We give the complete argument keeping the common auxiliary label $s$ (the root) unintegrated, since integrating it out first and using only moment orthogonality would not suffice. Write $K_{\rm soft}=T[A,A]$, with $A$ the exact swapped rectangle of \cref{prop:l20-rectangular}, and \begin{equation}\label{eq:merge-local-I-23} A=a\otimes1+r(\sqrt{30}\,Zv^*+2we^*)+E,\qquad \|E\|=O(q),\quad a=1+O(r). \end{equation} Both row and column squared norms of $A$ are at most $256a_\infty$ (with $a_\infty=\|a\|_\infty$). For two trace supports, retain their common auxiliary labels $s,t$ and split $s=t$ from $s\ne t$. If two nonempty raw supports have union of size at least two, their off-diagonal two-auxiliary map has norm $O(q)$. Distinct supports use a matching or three-edge path; equal supports use the restricted $K_{2,2}$ estimate. Output and auxiliary distinctness are both retained. If the two maps obtained from the core part of $A$ have the property of the preceding paragraph (norm $O(r)$ after one free transform) on both halves, write the modulated rectangles (rectangles $A$ with left and right multiplication operators $M_f,M_g$ by the displayed private multiplier functions $f,g$ and their reflected counterparts $\tilde f,\tilde g$) as $B_{st}=M_fAM_g$ and $D_{st}=M_{\tilde f}AM_{\tilde g}$. The private multipliers have modulus at most one, so positive Gram Schur order gives \begin{equation}\label{eq:merge-local-I-24} \left\|\mathbb E_{s\ne t}B_{st}B_{st}^*\right\| \le256a_\infty\|F_{\rm core}\|^2=O(q^2), \end{equation} where $F_{\rm core}$ is the core synthesis operator of \eqref{eq:merge-local-I-23}; and the same for $D$. Operator Cauchy--Schwarz bounds $\mathbb E B_{st}\otimes D_{st}^*$ by $O(q^2)$, with the private swap unchanged. Division by the score-square normalization $q$ gives $O(q)$. If both private maps instead have the property, use the input Grams and the column bound. Exact support enumeration covers all $51^2$ ordered pairs: 2537 use core output Grams and 64 use private input Grams. On $s=t$, cancel repeated roots. The identical-support term is $K_{\rm soft}+O(q)$. Other terms are raw traces on the symmetric difference, with at most twelve hole terms (terms where the common auxiliary label equals a fixed label) of size $q$. A raw trace with nonempty supports on both halves costs $O(q)$ after multiplication by $K_{\rm soft}$. For core/core or private/private placement, use the one-auxiliary form of \eqref{eq:merge-local-I-24}, with two raw norms $O(r)$. Pure core/private placement reduces to $A$ times a raw-star cross-kernel; expand \eqref{eq:merge-local-I-23}. Rank and remainder terms cost $O(q)$. Every leading edge has a coordinate evaluation at one endpoint. The higher/raw product has a bounded exceptional $e_0$ image and an $O(r)$ remainder, whereas the evaluation/raw image is \begin{equation}\label{eq:merge-local-I-25} \frac{\psi_S(x_i)-\mathbb E\psi_S}{\sqrt{p-1}}=O(r). \end{equation} The old factor $r$ makes these terms $O(q)$. A shared singleton pair gives $1_{x_i=y_j}-q$, whose positive equality mass is $O(q)$. One-sided differences give invariant functions of size $O(r)$; their leading one-sided ranks vanish under ordinary centering, and multiplication by $K_{\rm soft}-J=O(r)$ costs $O(q)$. Thus \begin{equation}\label{eq:merge-local-I-26} Q(K_{\rm soft}\odot H^2)Q=\sigma QK_{\rm soft}Q+O(q). \end{equation} The corresponding linear calculation gives \begin{equation}\label{eq:merge-local-I-27} Q(K_{\rm soft}\odot H)Q=QHQ+O(q),\qquad \|K_{\rm soft}\odot H\|=O(r). \end{equation} Here are the exceptional shared-label cases. Rank/star terms have a free raw core and private transform, each $O(r)$. For the product of two stars, the two arms (synthesis factors) from the untilted law are $(Z,v)$ and $(w,e)$. The cross pairing has a free leaf at its $(w,v)$ endpoint, since each half score uses at least three labels. For equal $(Z,v)$ pairings, two private leaves again give a free transform. Otherwise the private support is a singleton and the core support has at least two labels. Split its higher/raw product into the constant exceptional image plus an $O(r)$ remainder. The two exceptional images contract against the swapped private evaluations; the delta terms vanish by $\chi(0)=0$ and the remaining probability operator is $qQ/(p-1)$. It is $O(q^2)$, not an omitted order-$r$ block. The equal $(w,e)$ case exchanges core and private. Every single remainder costs $O(q)$. An $E$/star term applies $E$ fiberwise between two bounded product maps with the shared label retained. The $E$/rank term has free raw transforms; $E$/$E$ costs $O(\|E\|^2/r)$. These prove \eqref{eq:merge-local-I-27}. For a half support $S$ (a support contained in one half), extending the notation of \cref{imp:local:star-product}, let $U_S=(\psi_S-m_S)/r$ on mean-zero auxiliary labels and $M_S=m_S/r$. With $C$ the symmetric matrix, indexed by the half supports, whose entries are the collected coefficients $c_D$ of \eqref{eq:merge-local-I-21}, and $U$ the row of operators $(U_S)_S$, \begin{equation}\label{eq:merge-local-I-28} H=rUCU^*+rMCM^* . \end{equation} The two terms occupy respectively nontrivial translation sectors and the invariant sector. To specify the finite matrix gate without ambiguity, index all nonempty half supports by $S$. Let $D_{ij}$ be $+1$ or $-1$ according to the directed cross edge between coordinate $i$ and the reflected coordinate $j$, and zero if it is absent. The old matrix has singleton block $iD$, higher/singleton entry $\prod_{i\in S}D_{ij}$, its adjoint entry, and zero higher/higher block. The Gram matrix of the core raw mean functions $M_S$ is at most $16+O(r)$, by cube orthogonality and the core density. Group mixed means by their private singleton or pair support. Their raw Gram is at most $q[1+q/(1-q)+2qr/(1-q)]I$; for each fixed injective core the character supports have Gram $I+O(r)$. Conditional synthesis gives mixed mean Gram $I+O(r)$. The Gram matrix of the common actual stars is likewise $I+O(r)$ on nonconstant auxiliary labels. These estimates will price the invariant sector as well as the nonzero translation sectors. \paragraph{Physical completion.} Each half support has at least three labels. Complete character cancellation therefore requires at least three cross identifications, of positive row/column mass $O(q^3)$. Everywhere each single-support trace factor in \eqref{eq:merge-local-I-21}, before its coefficient, is at most $1/r$ in absolute value, so even at the configurations where a trace takes an exceptional value (the spikes), its square contributes $O(q^2)$ after the normalizations. Other collisions have mass $O(q)$ and bounded score by the repeated-root Weil bound (\cref{thm:weil}). This controls all physical deletions and their intersections. The positive constant $\eta=1/100$ added in the weight (its floor) and the Weil bound on the strict support (distinct labels) give uniformly positive bounded new marginal densities. The full identities for the new half-marginal density $g$ with respect to the fixed half law give $\|g-1\|_2=O(r)$. For each normalized star, the weighted affine Gram with weight $(g^{-1/2}-1)^2$ is real symmetric and a scalar multiple of the identity on mean-zero labels, with scalar its trace divided by $p-1$; this shows that multiplying the finite feature synthesis by $g^{-1/2}-1$ changes its norm by $O(r)$. Thus the leading $r$ operator changes by $O(q)$ under actual-marginal congruence. The finitely many invariant mean arms are pointwise bounded; their multiplication by $g^{-1/2}-1$ likewise has norm $O(r)$ by its $L^2$ bound, covering the second term of \eqref{eq:merge-local-I-28}. Finally, writing $T$ for the chamber operator of the tilted law on the induced half, \begin{equation}\label{eq:merge-local-I-29} T=g\otimes g+QTQ-(g-1)\otimes(g-1) \end{equation} keeps the constant rank positive and charges only $O(q)$. This proves that the leading bound transfers from the fixed half chart to the actual half marginal at every chamber cut. Remove from $\mathcal D_{51}$ the twelve supports containing fewer than three labels in one layer. Call the remaining dictionary $\mathcal D_{39}$. It has twelve supports of degree six, twenty-four of degree seven, and three of degree eight. Consequently \begin{equation}\label{eq:merge-local-I-30} \sigma_{39}=13/75,\quad \sum|c_D|=13/5,\quad |H_{\mathcal D_{39}}|\le14+r \quad\hbox{on strict physical support}. \end{equation} The last bound uses $(k-2)r+q$ for even degree $k$ and $(k-1)r$ for odd degree, before dividing by $r$. \begin{lemma}[Admissibility of the coherent root] \label{lem:imp:coherent39-law} For every rational $t\ge0$ and every $\eta>0$, normalize $\eta+(1+tH_{\mathcal D_{39}})^2$ against the old physical root at the prime $p\equiv3\pmod4$ fixed above. The resulting probability law has exactly the old root's support and accepts the six queries. It is invariant under the three chamber reflections $j\mapsto2a-1-j$, $a=0,1,2$, the rotation $j\mapsto j+2$, the simultaneous layer interchange, and the square-affine maps of the labels. Every slot is uniform. These assertions also hold for the primewise product on a block. In particular they hold at the selected parameter $t=67/40$ and floor $\eta=1/100$. \end{lemma} \begin{proof} The initial average in \eqref{eq:merge-local-I-20} makes the signed support dictionary invariant under the chamber reflections and the rotation. Simultaneous layer interchange permutes the four cubic supports and fixes the quartic support in each core; it preserves their signs and the twenty-five corresponding products. The filter defining $\mathcal D_{51}$ is imposed at every chamber and is unchanged by these permutations. The subsequent filter requiring at least three labels in each layer is also unchanged. Thus each of these permutations preserves the collected coefficients of $\mathcal D_{39}$ and fixes its score. Under $x_i\mapsto\alpha x_i+\beta$, with $\chi(\alpha)=1$, the substitution $s=\alpha s'+\beta$ fixes every character product in \eqref{eq:merge-local-I-21}, in both odd and even degrees. All the stated maps preserve the old physical root, so they preserve its tilted weight and normalizer. Since the weight is at least $\eta>0$, normalization is defined and the support is unchanged; query acceptance follows from that of the old root. Translations act transitively on the labels, so every slot is uniform. Tensor products give the block assertions. Only the simultaneous layer interchange is needed; independent flips of individual twins are not asserted. \end{proof} \begin{proposition}[Thirty-nine coherent traces at every sorting cut: the leading coefficients] \label{imp:local:coherent-39} Let $\Gamma$ be the coherent law at the endpoint parameter $t_*=12/5$, that is, the uniform law reweighted by $1/100+(1+(12/5)H_{\mathcal D_{39}})^2$ and normalized. It is invariant under the chamber reflections $j\mapsto2a-1-j$, $a=0,1,2$, and under the simultaneous interchange of the two layers $(j,\ell)\mapsto(j,1-\ell)$; these are the reflections occurring in the sorting sequences. (Independent flips of single twins are not symmetries and are not used.) There are absolute constants $C$ and $P_0$ such that for every prime $p\equiv3\pmod4$ with $p\ge P_0$ the Markov operators of $\Gamma$ at its cuts, on its actual marginals, obey \begin{equation}\label{eq:merge-local-I-31} T_{\rm chamber}\succeq-(5.413r+Cq)I,\qquad T_{\rm layer}\succeq-(2.19r+Cq)I, \end{equation} the first at all three chamber cuts. This proposition identifies only the leading coefficients $5.413$ and $2.19$; by itself it gives no bound at any specified prime. The explicit bounds used in the construction, with every remainder evaluated, are \cref{imp:local:finite-coherent-layer,imp:env:finite-coherent-chamber}. \end{proposition} \begin{proof} The chamber calculation for $\mathcal D_{51}$ above applies to the retained dictionary $\mathcal D_{39}$. There are 1493 core-output and 28 private-input covariance cases. Its strength is $\lambda=2t/(1+\eta+t^2\sigma)=12000/5021$. Exact rational gates (\cref{app:certificates}) give chamber coefficient $5413/1000$, core mean coefficient $7/100$ and mixed mean coefficient $21/100$. The invariant chamber price is below $\lambda(16\cdot7/100+21/100)<16/5$. At the layer cut a half is initially two independent directed cyclic triangles, on bases $\mathcal A=\{0,2,4\}$ and $\mathcal B=\{1,3,5\}$. The actual half conditions their six labels to be distinct, at cost $1+O(q)$. Each component has \begin{equation}\label{eq:merge-local-I-32} \Phi=J+rFM_0F^*+E,\quad \|E\|=O(q),\qquad M_0=\begin{pmatrix}iD_0&-I_3\\-I_3&0\end{pmatrix}, \end{equation} where $F$ is the synthesis operator assembled from the six feature maps of the preceding paragraph. Its arms (factors) are the three evaluations and three pair stars. The six omitted pair means give $+6qJ$, included in $E$. There is no higher/higher edge. For every retained trace each half support meets both triangles in one or two coordinates and has size at least three. In the quadratic product use $q^{-1}\mathbb E_{s\ne t}B_{st}\otimes D_{st}$. Operator Cauchy--Schwarz now uses $BB^*$ and $D^*D$: the small raw maps must be output $\mathcal A$ and input $\mathcal B$, or input $\mathcal A$ and output $\mathcal B$. The exact enumeration gives 1437 cases of the first kind and 84 of the second. Each raw map is $O(q)$; the component density $8/(1-q^2)$ and bounded row/column squares of $\Phi$ give the full $O(q)$ off-diagonal contribution. On the auxiliary diagonal, supports in opposite components use the one-label crossed argument with two $O(r)$ maps. If both lie in the same component, expand \eqref{eq:merge-local-I-32}. The rank and remainder terms cost $O(q)$; each star has an evaluation endpoint, so \eqref{eq:merge-local-I-25} controls the exceptional image. Two singleton supports instead give an equality kernel of bounded-density mass $O(q)$. For this particular dictionary, collecting all one-sided symmetric differences gives thirty pair supports of total absolute coefficient mass $8/25$. After conditioning the half to be six-distinct, every such raw trace is exactly $-q$. Therefore at either cut the full covariance, in the fixed induced-half chart, is, writing $K$ for the tensor square of the layer-cut kernel, \begin{equation}\label{eq:merge-local-I-33} K\odot H^2=\sigma K+O(q). \end{equation} This full-norm identity is not asserted on the independent triangle chart before conditioning. For the layer linear term expand the two copies of \eqref{eq:merge-local-I-32}. One star term and one rank term have, on both sides, free raw star factors carrying none of the displayed characters (passive factors). For two stars, the scalar is $r^2/r=r$. A coordinate/coordinate endpoint has a free leaf because the score uses at least three coordinates. Every higher/higher endpoint is opposite one of this type. The remaining coordinate/higher against higher/coordinate case either has a free leaf or has two identical pair-star exceptional images. The latter is the same shared-label $qQ/(p-1)$ contraction used above; all single remainders have norm $O(r)$. An $E$/star term is a fiberwise $E$ between bounded product maps; $E$/rank has free raw transforms and $E$/$E$ costs $O(\|E\|^2/r)$. Hence $K\odot H=H+O(q)$ on the induced half. The real vector space spanned by the real and imaginary parts of the layer feature functions that occur (the active layer realification) has dimension $54$; rational elimination proves coefficient $219/100$. Its raw-mean coefficient matrix is bounded below by $-21/100$. Group mean arms by the singleton or pair in one triangle. The normalized six-arm nonconstant Gram is $I+O(r)$; the three pair constant images add only $3q^2J$ before normalization. Fixed opposite-triangle character Grams are $I+O(r)$, so the complete mean frame is $I+O(r)$. Its invariant negative coefficient is below $\lambda(21/100)<1$. Thus no invariant sector is omitted. Physical collision deletion, positivity and actual-marginal transport follow exactly as in the physical-completion argument above: all retained half supports still have size at least three. The dictionary, all 1521 crossed cases, chamber and layer matrix gates and separate mean gates are reconstructed by \texttt{check\_coherent\_39\_all\_cuts.py} (\cref{app:certificates}). \end{proof} \subsection{One parameter \texorpdfstring{$\ulaw$}{u} for both cuts of the \texorpdfstring{$39$}{39}-trace law} The matrix bounds above were proved at the endpoint parameter $t_*=12/5$, because the finite checks are cleanest there. The law used in the construction has the smaller parameter $t=67/40$. The following proposition transfers the endpoint bounds to every $0\le t\le t_*$ by convexity---the leading matrix is affine in an explicit interpolation parameter $\alpha(t)$---at both the chamber cut and the layer cut simultaneously; all remaining terms are then evaluated directly at $t=67/40$. \begin{proposition}[The common coherent parameter interval] \label{imp:local:coherent-parameter} \label{imp:env:coherent-parameter} Keep $\eta=1/100$, $\sigma=13/75$ and the 39-trace score, and let $0\le t\le t_*=12/5$. Set \begin{equation}\label{eq:merge-local-I-43} z(t)=1+\eta+\sigma t^2,\qquad \lambda(t)=\frac{2t}{z(t)},\qquad \alpha(t)=\frac{\lambda(t)}{12000/5021}. \end{equation} Then $0\le\alpha(t)\le1$. In the leading matrices of the normalized coherent law, valid negative coefficients are \[ g_{\rm ch}(t)=(1-\alpha(t))\sqrt{30} +\alpha(t)\frac{5413}{1000},\qquad g_{\rm lay}(t)=\frac{219}{100}. \] The invariant mean branches obey the same displayed bounds. Each estimate in \cref{imp:local:finite-coherent-layer,imp:env:finite-coherent-chamber} below applies to the physical weight $\eta+(1+tH)^2$ by using this $t$, its scalar leading mass $z(t)$, and the corresponding leading coefficient. The error terms in the linear and covariance identities for the score itself do not change with $t$. A separately certified matrix bound at a specified parameter may improve its leading coefficient, provided the separate invariant-mean price remains below it. This changes neither the law nor its other prices. \end{proposition} \begin{proof} The exact factorization \begin{equation}\label{eq:merge-local-I-44} t_*z(t)-tz(t_*)=(t_*-t)(1+\eta-\sigma tt_*),\qquad 1+\eta-\sigma t_*^2=29/2500 \end{equation} gives $0\le\alpha\le1$. At either cut, with $M_{\rm old}$ and $C$ denoting the untilted leading matrix and the score coefficient matrix at that cut, the leading coefficient matrix is \[ M_{\rm old}+\lambda(t)C =(1-\alpha)M_{\rm old} +\alpha\bigl(M_{\rm old}+(12000/5021)C\bigr). \] The endpoint orders are those proved in \cref{imp:local:coherent-39}. The old chamber coefficient is $\sqrt{30}$; the old layer coefficient $(\sqrt3+\sqrt7)/2$ is less than $219/100$. Convexity gives the stated bounds. The old invariant centered leading operator is zero, so the separate invariant branches interpolate as well. For the finite calculation, expand the raw weight before normalizing. The old-root, linear and covariance terms have coefficients $z(t),2t,t^2$, respectively; the regular and exceptional collision weights are their explicit positive quadratic polynomials. Each primitive error is bounded separately below. Substituting these coefficients therefore prices the same physical law at both cuts. The $10q$ allowance for centering the layer mean arms is bounded at $t_*$ and remains valid for smaller $t$ (see the proof of \cref{imp:local:finite-coherent-layer}). For each fixed $t$, the positive endpoint majorants give uniformity in $p$; no monotonicity of the final price in $t$ is needed. \end{proof} \subsection{An explicit layer price for the coherent law} \label{imp:local:finite-coherent-layer-section} We now evaluate the layer-cut bound for the same $39$-trace law numerically. All norms in this subsection are taken in $L^2$ of the fixed uniform half law (the fixed chart), not in the tilted law's own marginal; the passage from the chart to the actual marginal was already bounded in the transport estimates above, so no extra factor for that change of measure is charged here. Fix $0\le t\le12/5$ and keep $\eta=1/100$, $L=13/5$, $\sigma=13/75$ and $z=z(t)=1+\eta+t^2\sigma$ from \cref{imp:local:coherent-parameter}. For $p\ge2^{32}$ set \begin{equation}\label{eq:merge-local-I-34} \begin{aligned} h&=1-9q,& d&=\frac8{1-q^2},& M&=d(1+q)^3,& \Gamma&=1+1000r,\\ B_H&=14+r,& W&=\eta+(1+tB_H)^2 . \end{aligned} \end{equation} Define positive coefficients \begin{equation}\label{eq:merge-local-I-35} \begin{aligned} C_{\rm soft} &=\frac{1100z+2tL\cdot100000+t^2\cdot200000+10}{h},\\ C_\times&=\frac W h[384M+72d^2(1+q)^5],\\ C_{\rm exc} &=\frac{9830400d^2}{h} [(1+\eta)q^2+2tLqr+t^2L^2q],\qquad C=C_{\rm soft}+C_\times+C_{\rm exc}. \end{aligned} \end{equation} Here $C$ is a finite coefficient, not an unspecified asymptotic constant. Put \begin{equation}\label{eq:merge-local-I-36} m=z-Cq,\qquad \delta=\frac{Cq}{m},\qquad c=\frac{4z\Gamma r+Cq}{m}. \end{equation} \begin{proposition}[Finite layer-cut bound for the coherent law in the fixed half chart] \label{imp:local:finite-coherent-layer} With $p\ge2^{32}$ and $0\le t\le12/5$ as fixed above, on the explicit gates $m>0$ and $c<1$, the normalized physical layer operator of the law in \cref{lem:imp:coherent39-law}, represented on the fixed uniform six-distinct induced half and written $T$, satisfies \begin{equation}\label{eq:merge-local-I-37} -g_{21}rI\preceq T\preceq(1+B_{21}q)I, \end{equation} where \begin{equation}\label{eq:merge-local-I-38} g_{21}=\frac{z(219/100)\Gamma+Cr}{m} +\frac{C^2qr}{m^2},\qquad B_{21}=\frac{C^2q}{m^2(1-c)}. \end{equation} Its marginal defect (the difference between its actual half marginal and the fixed chart marginal, as a density minus $1$) has $L^2$ norm at most $\delta$, hence variance at most $\delta^2$. Its pointwise marginal range ratio is at most the old range ratio multiplied by $W/\eta$. Evaluation of these positive majorants at the endpoint $p=X$ (the lower endpoint of the interval) is valid uniformly for every prime $p\ge X$. The separate chamber inequalities and the completion inequalities for the law itself (not a converted one) remain to be checked. \end{proposition} \begin{proof} We first justify every finite constant. A cyclic triangle has density $d=8/(1-q^2)$ relative to its three-label cube and exactly $(p+1)/4$ completions of a directed pair. The inherited six-cycle expansion gives \eqref{eq:merge-local-I-32} with \begin{equation}\label{eq:merge-local-I-39} \|E\|\le(6+51d)q<500q,\qquad \|rFM_0F^*\|\le\kappa(1+5r)r,\quad \kappa=(\sqrt3+\sqrt7)/2 . \end{equation} The twelve star entries are six evaluation/evaluation and six evaluation/pair entries. The positive row and column bound is $M$, and $0\le\Phi\le64$, so their squared norms are at most $64M<600$; also $\|\Phi\|<2$. Consequently the old two-component root equals its constant plus leading star operator with remainder at most $1100q$, since $1000+[\kappa(1+5r)+500r]^2<1100$. For completeness the finite product bounds used next hold also when a raw symmetric-difference support is the full triangle. If $|S|=2$ and $1\le|T|\le3$, the normalized pair star times $\psi_T$ has decomposition $h_{ST}e_0^*+R_{ST}$. The exact diagonal image is $(\mathbb E\psi_S\psi_T-m_Sm_T)/\sqrt{1-q}$. Off the auxiliary diagonal, a matching/path or restricted $K_{2,2}$ map costs at most $2\sqrt d\,r<6r$. The mean-zero diagonal part is below $2r$, using $D_H^*D_H=(1-2q)P_H+(1-q)J$ and the at-most-three removed roots. The constant-input part is at most $2r$. Thus $\|R_{ST}\|\le10r$, $|h_{ST}|\le2$, and $S\ne T$ gives $|h_{ST}|\le3r$. A raw singleton gives a whole product at most $13r$. A coordinate times a raw pair or triple has norm at most $\sqrt d\,r<3r$, by fixing that coordinate and retaining a free Paley transform. Every whole product has norm at most two. The coarser constants $100r,4r,2$ will suffice. There are 24 one-component leading terms in the linear rooted expansion. Each costs at most $4q$. Of the 144 two-component terms, 126 have a free evaluated leaf and cost at most $10q$ each; fixing that coordinate leaves conditional density at most $4/(1+q)<4$. The 18 exceptional evaluation/pair against pair/evaluation terms have residual at most $400r+10000q+8q^2<500r$ before their old factor $r$. This includes the exact double-$e_0$ contraction. The 24 remainder/star placements cost at most $24\cdot4\cdot500q$; the two remainder/rank terms cost $1000rq$, and the remainder/remainder term costs $250000rq$. Their sum is below $100000q$ per trace. Summing the absolute coefficient mass $L$ proves the linear price used in \eqref{eq:merge-local-I-35}. For the quadratic term, each of the 1521 valid crossed factorizations has two raw two-label maps at most $6q$. Its positive Gram CS bound is at most $600\cdot9\cdot4q=21600q$. The diagonal two-sided raw-trace bound is at most $6100q$: opposite components use two raw transforms of norm at most $2r$, giving $2400q$, while a common component uses its rank, twelve star entries and $500q$ remainder, followed by the other component of norm less than two. The evaluation endpoint controls its exceptional diagonal image. Holes cost at most $32L^2q$. Collect the one-sided pair terms only after conditioning both halves to be distinct; then they are exactly $-q$ and have absolute coefficient mass $8/25$. Thus the full induced-half covariance error is at most \begin{equation}\label{eq:merge-local-I-40} \frac qh\{(21600+6100+32)L^2+4(8/25)\} <200000q/h. \end{equation} Before conditioning a pair spanning the two triangles may have trace $1_{x_i=x_j}-q$, so no unconditioned full-norm claim is used here. For collisions in the actual kernel, twelve equalities between labels at different bases make the untilted (old) root kernel vanish. The six remaining twin events have positive total price $384Mq/h$; the eighteen cross-component events cost $72d^2(1+q)^5q/h$. Multiply their union by $W$. Partial root repetitions still satisfy the even/odd degree bound in \eqref{eq:merge-local-I-30}. Complete cancellation requires a three-matching between the halves. There are at most $\binom63^2\,3!=2400$ such matchings. The input-half cube density is at most $d^2/h$, the root kernel at most 4096, and each matching has mass $q^3$. The unrestricted score bound $L/r$ therefore gives exactly $qC_{\rm exc}$. Positive unions include all further collisions and intersections; no coupled mask was removed inside a norm. The finite actual-star Gram is at most $1+182r$. Indeed every conditional vertex has at least $(p-11)/4$ choices, and the common actual-star identities give off-diagonal Gram entries at most $7r$ among 27 active arms. The fifteen mean arms have Gram at most \begin{equation}\label{eq:merge-local-I-41} \frac{(1+5r)(1+10r+5q)}{1-9q}\le1+16r: \end{equation} grouping by singleton/pair support in one triangle, using its raw six-arm frame, and then using the pointwise character Gram of the other triangle. Both are bounded by $\Gamma$. Each mean arm has expectation at most $100q/h$. Before half conditioning its raw mean is zero when the support meets the two triangles in $1$ and $2$ labels, and $q^2$ when it meets them in $2$ and $2$ labels. Removing nine equalities costs $27qr$, except complete two-pair cancellation of probability at most $18q^2$; division by $r h$ gives $(27+19r)q/h<100q/h$. With mean synthesis norm at most two, coefficient norm at most $\sqrt\sigma<1/2$, and fifteen arms, centering the raw-mean contribution to $2tH$ costs less than $10q$. Nonconstant auxiliary arms already kill constants by translation invariance. We have therefore proved the exact decomposition $T_{\rm raw}=zJ+L_{\rm cen}+R$ with \begin{equation}\label{eq:merge-local-I-42} L_{\rm cen}1=0,\quad \|R\|\le Cq,\quad L_{\rm cen}\succeq-z(219/100)\Gamma rI,\quad \|L_{\rm cen}\|\le4z\Gamma r . \end{equation} The lower order uses the 54-dimensional rational gate, the separate invariant mean gate and \cref{imp:local:coherent-parameter}; the upper norm follows from $\kappa+\lambda\sqrt\sigma<4$. The actual raw scalar mass is at least $m$. After normalization the constant entry is exactly one, the off-diagonal vector has norm at most $\delta$, and the centered block has norm at most $c$. By \cref{lem:block-completion}, the positive constant square costs at most $\delta^2$ below, and the separated upper blocks cost $\delta^2/(1-c)$. These are precisely \eqref{eq:merge-local-I-38}. The pointwise weight bounds $\eta\le w\le W$ prove the range assertion without a pointwise closeness claim. Finally every numerator after its indicated power of $q$ or $r$ is removed has nonnegative coefficients and increases with $q,r$; $h,m,1-c$ decrease on their positive gates. Rational outward endpoint evaluation is uniform. The independent checker rebuilds the 39-support dictionary, both collected diagonals and 136 scalar quantities at eight endpoints, authenticating the separate matrix and triangle-product certificates. Its parameter replay checks 72 endpoint/parameter cases and 1296 rational quantities, recovering the values at the fixed parameter $t=t_*$. At $X=2^{45}$ the selected $t=67/40$ gives $g_{21}<2.869198$ and $B_{21}<0.460808$, compared with $g_{21}<3.163793$ and $B_{21}<0.947552$ at $t=t_*$. \end{proof} At the selected exact parameter $t=67/40$, the chamber strength is $\lambda=402000/179557$ and a rational matrix gate improves the convex chamber coefficient to $5.41674864$. The checker \texttt{check\_coherent\_39\_selected\_matrix.py} reconstructs the physical dictionary and directed reflected matrix, proves all 56 rational LDL pivots positive, and verifies all 1596 exact reconstruction identities. The invariant mean order remains below $3.2$. The parameter interval above is used for the finite remainder and layer estimates; this stronger matrix gate is used only at its stated exact parameter. \subsection{A finite chamber price for the coherent law} \label{imp:env:finite-coherent-section} This is the corresponding numerical evaluation at the chamber cut, for the same law \cref{lem:imp:coherent39-law} and with the same convention: all norms are in $L^2$ of the fixed uniform chamber half law, and no extra change-of-measure factor is charged here. Throughout this subsection \begin{gather*} q=p^{-1},\quad r=\sqrt q,\quad p\equiv3\pmod4, \quad p\ge2^{40},\\ 0\le t\le\frac{12}{5},\quad\eta=\frac1{100},\quad \sigma=\frac{13}{75},\quad s=z(t)=1+\eta+t^2\sigma. \end{gather*} The weight of the law (before normalization) is $w=\eta+(1+tH)^2$. Recall that the $39$ coefficients in $H$ are $\pm1/15$, of total absolute mass $\ell=13/5$ (denoted $L$ in the preceding subsection). The degree count and Weil estimate in \eqref{eq:merge-local-I-30} give \begin{equation} |H|\le B_H:=14+r \label{imp:env:coherent-score-bound} \end{equation} on the support of the uniform law. Use the exact rectangle of the uniform law (\cref{prop:l20-rectangular}) and its probability-normalized decomposition \[ A=a\otimes1+r(\sqrt{30}Zv^*+2we^*)+E, \qquad \|E\|\le N_0, \] with $N_0$ the nonstar bound of \cref{imp:env:finite-coherent-chamber}, and where the repeated letter $w$ in this rectangle denotes its four-coordinate feature function, not the weight $w$ above. Write $a_+$ for a pointwise upper bound on $a$, $a_2$ for its $L^2$ bound, and put \[ \theta=(1-q)(1-3q)(1-7q),\qquad h=(1-4q)(1-5q),\qquad D_6=\frac{16}{\theta h}. \] The row and column squared norms of $A$ are at most $256a_+$. Let $K_\nu$ be its swapped product after compression to the old six-distinct induced half. A norm-bounded independent-half remainder costs at most $1/h$; an unchanged leading feature has its original coefficient after compression. \begin{lemma}[Full coherent covariance] \label{imp:env:coherent-full-covariance} One has \[ \|K_\nu\odot H^2-\sigma K_\nu\|\le E_2/h, \] where \begin{align} E_2=q\biggl[256a_+\biggl\{ \frac{20992}{225\theta}+\frac{2108}{225(1-q)}\biggr\} +\biggl(\frac{32}{225}+\frac8{25}+\frac{2028}{25}\biggr)a_2^2 \biggr]<26400q.\label{imp:env:coherent-E2} \end{align} This is a full operator estimate, including its constant sector. \end{lemma} \begin{proof} For each ordered pair of score supports, keep their common auxiliary labels and split the diagonal from its complement. On the complement, use the cheaper of the two valid whole-rectangle Cauchy--Schwarz factorizations. A different-support core product costs $4q/\sqrt\theta$ and an equal-support product twice that; the private costs are $q/\sqrt{1-q}$ and twice that. The exact ordered counts of support pairs, by core and private product coefficient, are \[ \begin{array}{c|rrr} \text{core product coefficient}&16&32&64\\ \text{number}&804&56&41\\ \hline \text{private product coefficient}&1&2&4\\ \text{number}&184&240&196. \end{array} \] Multiplying by the rectangle row or column square and by $1/225$ gives \[ 256a_+q\left\{\frac{17280}{225\theta} +\frac{1448}{225(1-q)}\right\}. \] The operator Cauchy--Schwarz uses the two output Grams for the swapped rectangle, or the two input Grams in its private version. It does not introduce a second copy of either auxiliary label. On the auxiliary diagonal, collect equal symmetric differences before taking absolute values. Every nonzero one-sided difference has size two. Its trace in the induced half is exactly $-q$; the absolute coefficient mass is $4/25$ on each side. For the two-sided differences, the private raw-star maps give weighted cost $44/15$, and the remaining core maps give $3712/225$. A core singleton has norm $r$; a higher raw core star has norm at most $4r/\sqrt\theta$. The only unmatched terms are sixteen core-singleton/private-singleton terms of total mass $32/225$. Their raw trace is $1_{x=y}-q$, and the accepting rectangle vanishes at $x=y$, so their operator is exactly $-qK_\nu$. Finally the repeated-root holes cost at most $12\ell^2q\|K_\nu\|$. These are precisely the remaining terms in \eqref{imp:env:coherent-E2}. The one-sided identities are asserted after induced-half conditioning; before conditioning a core/private pair may coincide. The other remainder estimates are compressed with the single factor $1/h$. \end{proof} \begin{lemma}[Finite coherent linear error] \label{imp:env:coherent-linear-finite} With $E_1=12500q$, \[ \|Q(K_\nu\odot H-H)Q\|\le E_1/h, \qquad \|K_\nu\odot H\|\le(12r+E_1)/h. \] \end{lemma} \begin{proof} Here are explicit rounded product bounds sufficient for the assertion. The inherited positive endpoint majorants give \[ N\le282q,\qquad \|a-1\|_2\le4.5r, \qquad a_+,a_2,\|Z\|<1.001, \qquad \|K_\nu-J\|<15r. \] For higher core supports $S,T$, split the normalized product map by the constant diagonal vector $e_0=(p1_{u=v}-1)/\sqrt{p-1}$, its mean-zero diagonal, and its off-diagonal complement. Set \begin{gather*} b_1=0,\quad b_2=q,\quad b_3=2r,\quad b_4=2r+q,\\ D_2=\frac2{1-q},\quad D_3=\frac4{(1-q)(1-3q)},\quad D_4=\frac{16}{\theta}. \end{gather*} For $S\ne T$, writing $c=|S\cap T|$ and $d=|S\triangle T|$, the three pieces are bounded respectively by \[ \sqrt{D_{|S\cup T|}},\qquad \frac{1+cr+b_{|S|}+b_{|T|}}{\sqrt{1-2q}},\qquad \frac{b_d+cq+b_{|S|}b_{|T|}}{r\sqrt{1-q}}. \] For $S=T$ double the first bound, omit the last, and remove the constant image $1/[r\sqrt{1-q}]$. Its remaining variation is at most $(|T|q+b_{|T|}^2)/[r\sqrt{1-q}]$. These bounds follow from the two-Paley matching/path extraction or the restricted $K_{2,2}$ bound, and the exact Gram of the projected auxiliary diagonal. Their orthogonal-input square sum, the eleven-star expression for $Z$, and its singleton correction give residual bound 22 and exceptional coefficient at most $.259/r$. The four-singleton aggregate has product bound 9. Each expression is a positive endpoint majorant; the displayed rational constants hold already at $p=2^{40}$. There are thirteen pure-core terms (whose supports at this cut lie in the core labels of the halves). For each, the rectangle expansion prices the three rank and star classes, the three classes containing a nonstar remainder, and the raw invariant means by the following coefficients of $q$: \[ 9.1,\quad278,\quad400,\quad565,\quad801,\quad1,\quad61. \] For clarity the nontrivial rounded expressions are \begin{align*} 278&>2(1+4.5r)(22\sqrt{30}+18),\\ 400&>30r\,22^2+60(.259)22 +\frac{30(.259)^2r}{1-q} +4\sqrt{30}r\,22\cdot9 +4\sqrt{30}(.259)9+4r\,9^2,\\ 801&>2\cdot282\{\sqrt{30}(.259+22r)+18r\}. \end{align*} The factor $1+4.5r$ is the invariant weighted-star correction from $a-1$. The large constant output of a pure-core rank/star term is killed by $Q$ on that half; its nonconstant variation was included in the residual bound 22. The retained uncentered rank/star norm, after weighting all thirteen terms, is below $6r$. The mean contribution uses $(2+r)^2\|K_\nu-J\|r<61q$. The sum of these seven prices is below 2300. The other twenty-six terms are mixed. Weighted raw-star synthesis gives a rank/rank cost of at most $91q$. The free core and private transforms give a rank/star cost of $61q$. For the two cross-arm star/star terms, the $w,v$ triple map has a free Paley leaf and norm below $6r$, while $Z,e$ has norm below 1.001; their price is 132. Equal $Z,v$ arms have exceptional amplitude at most $.259$ and residual $24r$; equal $w,e$ arms have amplitude at most $.501$ and residual $6r$. The double exceptional contractions are exactly $qQ/(p-1)$, not products of their separate norms. These prices are 375 and 26. The nonstar/star chain applies the input product, then $E$ fiberwise, then the output product, keeping both shared labels. Their norms are at most 1.04 and 1.001, so both placements cost less than \[ 2(\sqrt{30}+2)(1.04)(1.001)282q<4500q. \] Nonstar/rank and nonstar/nonstar cost 566 and 1. Thus the mixed price is below 6000. The total is bounded by $(13\cdot2300+26\cdot6000)q/15<12500q$. For the full-norm assertion, the raw score coefficient matrix has absolute row sum at most $1/3$. Cube star ranges are orthogonal, so compression gives $\|H\|\le D_6r/3<5.334r$. Adding the retained rank/star norm below $6r$ and the error just proved gives the stated $12r+E_1$ bound, with its compression price. \end{proof} We state the final finite scalar interface explicitly. Let $N_0,D, \epsilon,\chi$ be the authenticated old raw nonstar, positive collision, scalar-normalizer and normalized marginal-variance bounds: $N_0=N_{\rm ns}$, $D=D_{\rm bal}$, $\epsilon=\eps_Z$ and $\chi=\chi_p^+$ in the notation of \cref{prop:l20-completion,prop:l20-collisions}. Put \begin{align} P_*&=144\cdot65536D_6q^3,\nonumber\\ C_w&=[\eta+(1+tB_H)^2]D +P_*[\eta+1+2t\ell/r+t^2\ell^2/q],\nonumber\\ L&=\frac{(12r+E_1)/h+B_HD+\ell P_*/r}{1-\epsilon},\nonumber\\ V&=\frac{E_2/h+(B_H^2+\sigma)D+(\ell^2/q+\sigma)P_*} {1-\epsilon},\nonumber\\ z&=s-2tL-t^2V,\qquad \delta=\frac{s\sqrt\chi+2tL+t^2V}{z}. \label{imp:env:coherent-normalization} \end{align} (From here $z$ denotes the proved lower bound $s-2tL-t^2V$ for the scalar mass whose leading value was called $z(t)$ above; the letter $L$ in $z$ is the linear error term of the display, not the block budget.) Let $\Gamma=1+434r$. Let $g_*$ be any number such that both the nontrivial and invariant branches at the specified $t$ have leading negative coefficient at most $g_*$; the value $g_{\rm ch}(t)$ of \cref{imp:env:coherent-parameter} may be used, or a sharper certified coefficient at the specified $t$. In particular the selected $t=67/40$ uses $g_*=5.41674864$. Define \begin{align} E_*&=sN_0+2tE_1/h+t^2E_2/h+C_w,\nonumber\\ G&=\frac{s g_*\Gamma r+E_*}{(1-\epsilon)z},\qquad c=\frac{s\sqrt{30}\Gamma r+2tD_6r/3+E_*}{(1-\epsilon)z}. \label{imp:env:coherent-final-prices} \end{align} \begin{proposition}[Finite chamber-cut bound and marginal data for the coherent law] \label{imp:env:finite-coherent-chamber} The explicit gates $z>0$, $c<1$, and $\delta<1$ hold on the stated domain. The normalized physical operator of \cref{lem:imp:coherent39-law}, on the fixed old induced half and written $T$, satisfies \[ -(G+\delta^2)I\preceq T \preceq\left(1+\frac{\delta^2}{1-c}\right)I. \] Its marginal variance is at most $\delta^2$, and its marginal range ratio is at most the old ratio times $[\eta+(1+tB_H)^2]/\eta$. Every endpoint price is uniform for all primes $p\equiv3\pmod4$ above the endpoint. \end{proposition} \begin{proof} Complete character-root cancellation needs three cross identifications for each of the twelve degree-six traces, or four for each of the three degree-eight traces. There are at most $12\cdot3!+3\cdot4!=144$ matchings. The raw root is bounded by 65536 and the input half has cube density at most $D_6$, giving the positive exceptional row/column mass $P_*$. Outside it, cancellation only reduces the Weil price in \eqref{imp:env:coherent-score-bound}; everywhere $|H|\le\ell/r$. Thus $C_w$ bounds the difference between the soft kernel and the kernel with the distinctness conditions imposed, including all intersections. The same argument and the two lemmas give the full normalized-old prices $L$ and $V$. The new scalar mass is at least $z$, and its centered row has norm at most $\delta$. The general actual-star Gram bound applies to all 63 nonempty supports. Every distinct-feature entry is at most $7r$, giving $\Gamma$. The exact matrix inequality of \cref{imp:env:coherent-parameter} (its certified gate) gives the nontrivial negative leading price $s g_*\Gamma r$. In the invariant sector the bound from the core mean features price is $16/(\theta h)$, and the mixed price is at most \[ \frac{[1+q/(1-q)+2qr/(1-q)](1+45r+60q)}h. \] The latter follows by enlarging the core character list to all 15 nonempty supports: each distinct-support entry is at most $3r+4q$, so its row sum is at most $1+42r+56q$. The respective negative coefficient orders $-7/100$ and $-21/100$ keep this invariant branch strictly below the nontrivial branch. The full positive centered price follows from $\|M_{\rm old}\|=\sqrt{30}$ and $\|H\|\le D_6r/3$. This proves the centered bounds $-G$ and $c$. The constant-block bounds of \cref{lem:block-completion} cost at most $\delta^2$ below and $\delta^2/(1-c)$ above. The pointwise multiplier lies between $\eta$ and $\eta+(1+tB_H)^2$, proving the range statement. After substituting $q=r^2$, all new normalized numerator majorants are positive increasing functions of $r$, while $z$ and $1-c$ decrease. For example the three exceptional terms in $C_w/r$ have powers $r^5,r^4,r^3$. The inherited majorants have the same endpoint property. Thus the gates and orders extend uniformly above the endpoint. Exact coefficient collection, finite product gates and an independently assembled scalar replay accompany the proof (\cref{app:certificates}). For the endpoint parameter $t=t_*$ at $2^{45}$, with $g_{20}$ the negative coefficient in $T\succeq-g_{20}rI$ and $B_{20}$ the excess in $T\preceq(1+B_{20}q)I$ (both formed from $G,\delta,c$ by the formulas above, as $g_{21},B_{21}$ are for the layer cut), the values are $g_{20}<5.441282211737$ and $B_{20}<1100.871034665$. These are local interfaces; the layer price, native completion and full scalar comparison are checked separately. \end{proof} \begin{proposition}[The coherent score on a single collision] \label{imp:env:coherent-single-pin} For the same $39$-trace coherent law, put \[ B_c=\frac{64}5+\frac85r,\qquad B_s=10+\frac{11}5r,\qquad B_x=\frac{26}3+\frac{31}{15}r,\qquad B=14+r. \] Let $A_c,A_p,A_m$ be the positive collision bounds \[ \begin{split} e_2&=r+48q,\quad e_3=5r+96q,\quad e_4=17r+192q,\\ \Lambda_c&=(1-r-24q)^4(1-6q)^2,\\ A_c&=\frac{32q(1+e_3)^2(1+e_4)^3}{\Lambda_c},\\ A_p&=\frac{32q(1+e_2)(1+e_3)^2(1+e_4)^2}{\Lambda_c},\\ A_m&=\frac{(1+e_4)^6}{\Lambda_c} (3712q^2+81920q^3+1245184q^4+12582912q^5+67108864q^6). \end{split} \] With $w(x)=\eta+(1+tx)^2$, replace only $C_w$ in the negative price of Proposition~\ref{imp:env:finite-coherent-chamber} by \[ C_{\rm pin}=A_cw(B_c)+A_p[w(B_s)+w(B_x)]+A_mw(B) +P_*[\eta+1+2t\ell/r+t^2\ell^2/q]. \] Retain the previous $z,\delta,c$ and all positive, variance and range prices. The resulting lower coefficient is uniformly valid for $p\ge2^{40}$ and each fixed parameter $t$ for which the leading matrix bound has been certified. \end{proposition} \begin{proof} At the chosen chamber cut, numbering the label $(j,\ell)$ by $2j+\ell$, the coordinate sets are \[ \text{cores: }\{0,1,4,5\},\ \{6,7,10,11\}; \qquad \text{private pairs: }\{2,3\},\ \{8,9\}. \] Only their sixteen core/core and four private/private coincidences survive the soft accepting kernel. For exactly one equality $x_a=x_b=u$, use $\chi(v-u)^2=1-1_{\{v=u\}}$ in every score monomial and collect the remaining supports. In the score divided by $r$, the deleted evaluation contributes at most $r$ times its absolute coefficient. No remaining support has fewer than four labels. For a remaining support of degree $d$, the even-degree character price is $d-2+r$ and the odd-degree price is $d-1$. Exact collection gives eight pins with bound $B_c$, six with $B_s$, and six with $B_x$. The eight $B_c$ pins join the output $a$ pair to the input $a$ pair, or output $c$ to input $c$. The other two classes are \[ \begin{array}{c|l} B_s&(0,6),(1,7),(4,10),(5,11),(2,8),(3,9)\\ B_x&(0,7),(1,6),(4,11),(5,10),(2,9),(3,8). \end{array} \] For $p\ge2^{40}$, $B_c$ dominates the other two prices, so the original mutually exclusive core orientations retain their total incident charge $32q$. For each output private coordinate, the two input private pins have the same incident cyclic-extension weight, at most $16$, and one belongs to each of the $B_s,B_x$ classes. Their row charges are therefore $32q$ each. The counts of extensions of a pinned pair to full labellings (the extension histograms) are unchanged within the two groups and give $A_c,A_p$; transposition gives the same column bounds. The strata with exactly one coincidence are disjoint from the set with at least two coincidences, already bounded by $A_m$. Keep the original $A_m$ with the generic score bound $B$, and the entire exceptional mass $P_*$ with the worst score $\ell/r$. Schur's test gives the displayed collision price. Recompute the numerator of $G$ in \eqref{imp:env:coherent-final-prices}, with $C_{\rm pin}$ in place of $C_w$ in $E_*$, using only positive terms, retaining the old denominator and constant-block charge. This proves the same-law substitution without subtracting monotone majorants. All normalized numerator prices increase with $q$ and $r$, and the previous denominators decrease on their gates, proving endpoint uniformity. The independent replay verifies the 20 support collections, 180 finite identities and all 35 endpoint/parameter cases. At $p=2^{45}$ and the rational parameter $t=3337/2048$ (a rational below the endpoint $t_*=12/5$ at which this refined check is run; the selected construction uses $t=67/40$ with the coefficient above), the refined coefficient is $g_{20}<5.434524687965$, with the positive and marginal prices unchanged. \end{proof} \space % End sections/20b_selected_refinements \subsection{Values of the bounds at the seven interval starts}\label{subsec:positive-root-caps} The preceding subsections proved bounds for the tilted law in terms of quantities evaluated at the start of each interval. The following certificate records those values at the seven starts, checked by exact and outward-interval arithmetic; the table at its end is the form in which later sections use them. \begin{certificate}[The positive roots]\label{cert:positive-root-caps} The chamber caps for the selected individual-square (pair-score) laws combine \cref{imp:local:collision-gap,imp:env:finite-gap-chamber,imp:env:physical-interpolation}; their layer prices use \cref{imp:env:layer-resummation} where it improves the retained finite price. The last band uses \cref{imp:local:coherent-parameter,imp:env:coherent-parameter,imp:env:coherent-single-pin}, with the exact matrix gate at $\ulaw=67/40$. All prices concern the same tilted law at both cuts, and that law's actual marginal enters the restoration. Every positivity or contractivity condition required above --- in particular $z_->0$, $\Delta_g>0$, $\rho_{\rm in}>0$, $c_{\rm ch}<1$, $d_\ulaw<1$ and $gX^{-1/2}<1$ at each endpoint $X$ --- is checked in outward interval arithmetic, with the uniform endpoint majorants proved above. The exact selected data are the \texttt{local.spectra} and \texttt{local.further\_root\_law} entries of \path{research/push_2026_10_25/global/refined_parent.json}. They agree exactly with the native data authenticated by \path{research/improvements_2026_10_25/verify.py}; only scalar charges are reanchored by \path{research/push_2026_10_25/verify.py}. The former reruns independent collision, pair-gap, interpolation, resummation, coherent covariance, selected matrix, finite chamber, finite layer and single-pin checkers. Its full tier regenerates the native completion. The latter checks exact equality of all native records and reruns the independent closing and restoration assemblies. At $L_{\rm loc}=585$, the exported prices, rounded upward, are: \begin{center}\scriptsize \begin{tabular}{@{}llllll@{}} \toprule piece start & law, $\ulaw$ & cut & $g$ & $c^+$ & block cap\\ \midrule $2^{30}$ & individual squares, $711/4096$ & L20 & $5.476619678296$ & $25.456659470084$ & $5.476623331076$\\ & & L21 & $6.313078885225$ & $3.988889092310$ & $6.313079545011$\\ $2^{31}$ & individual squares, $1021/4096$ & L20 & $5.474335244881$ & $27.623843030000$ & $5.474337162024$\\ & & L21 & $6.315256713466$ & $3.962812801799$ & $6.315257030740$\\ $2^{32}$ & individual squares, $1455/4096$ & L20 & $5.471257426364$ & $30.397461416086$ & $5.471258447645$\\ & & L21 & $6.312562621834$ & $3.927444212402$ & $6.312562774077$\\ $2^{34}$ & individual squares, $833/1024$ & L20 & $5.464133834236$ & $36.835698528597$ & $5.464134125055$\\ & & L21 & $6.307298870667$ & $3.877354549660$ & $6.307298906003$\\ $2^{36}$ & individual squares, $3851/4096$ & L20 & $5.460775686025$ & $37.085210712622$ & $5.460775755114$\\ & & L21 & $5.426082230198$ & $1.143781717023$ & $5.426082232316$\\ $2^{40}$ & individual squares, $4049/4096$ & L20 & $5.457521105807$ & $37.019255725148$ & $5.457521109684$\\ & & L21 & $4.646587567237$ & $0.075183415124$ & $4.646587567244$\\ $2^{45}$ & coherent 39, $67/40$ & L20 & $5.434450251962$ & $983.324753609660$ & $5.434450254811$\\ & & L21 & $2.869197519095$ & $0.460807795864$ & $2.869197519096$\\ \bottomrule \end{tabular} \end{center} The seven per-prime marginal variances and range ratios are recorded as exact rationals in the corresponding rows of the data file named above and displayed in \cref{tab:data:positive-roots}. They are bounds in the fixed uniform chamber half, with its actual root marginal retained. No return to a uniform root is made in computing the restorations. \end{certificate} The finite tables retain the larger choice $\mathfrak b_{\rm cert}=6+51d_\mu$ in the layer formulas and the corresponding certified remainder prices. Since $\mathfrak b\le\mathfrak b_{\rm cert}$, these remain valid majorants for the same laws. The sharper triangle estimate and \cref{lem:native-pair-linear} do not change the chosen weights or permit an uncharged change of the actual half marginals. The block caps of L20, rounded upward, give $w_{\rm D}=w_{\rm S}$, and those of L21 give $v_{\rm L}$ (\cref{rem:middle-weights}). The restorations use actual budget $570$ and the respective maximum block cardinalities $\lfloor L/\log X\rfloor$ ($L=570$), namely $27,26,25,24,22,20,18$ at the seven starts; local operator tensorization uses budget $585$. \begin{remark}[The family of tilts]\label{rem:positive-root-family} The root $g(\lambda)$ of \eqref{eq:root-cubic} is the limit of the chamber coefficient $g^\ulaw_{20}$ as $p\to\infty$ (\cref{prop:root-chamber}: $\Gamma_{20}\to1$, $z_{\rm raw}\to s$). It decreases from $g(0)=\sqrt{30}$, the limit of the uniform root, to about $5.466411$ at $\lambda=1/2$, $5.456962$ at $\lambda=24/25$ ($\ulaw=3/4$), $5.456161$ at $\lambda=1$ ($\ulaw=1$, the largest value of $2\ulaw/(1+\ulaw^2)$). For comparison, the leading matrix of a square-of-the-average weight has strength $6\ulaw/(3+\ulaw^2)$: the same cubic gives $5.443543$ at $\lambda=4080/2467$ ($\ulaw=51/40$) and $5.442090$ at its maximum $\lambda=\sqrt3$. These matrix values explain the historical interest in that family; a finite law must also pay its mixed-product errors. The gain is at order one; the costs are at order $r$: the layer coefficient tends to $\sqrt3+\sqrt7$ for every $\ulaw$, the half marginal moves, and the range ratio grows like $(1+\ulaw(2+r))^2/(1-\ulaw c_{\rm cond})^2$ and enters the restorations through the per-block product of the per-prime range ratios, bounded by $M_{\Blk}\le R_\ulaw(X)^n$ in \cref{lem:record:root-marginal}(iv). The selected seven middle pieces and their parameters are those of \cref{def:positive-root}. The coherent last-band law has its own full chamber and layer estimates above; the one-layer root is unchanged. \end{remark} \paragraph{Consequences and what to read next.} \Cref{thm:weil} (the scores); \cref{lem:layer12-geometry} and \cref{lem:marginals} (the symmetries); \cref{lem:l20-star-matrix,prop:l20-completion,prop:l20-rank4,prop:l20-rectangular,prop:l20-collisions} (the star matrix and the frame cap, the normalizer, the rank-four Gram, the rectangle and the collision cap of the uniform root); \cref{lem:general-star,cor:star-matrix,rem:realified-gates} and \cref{lem:spec:affpair}(d) (stars); \cref{cor:raw-pair-maps,lem:swapped-rectangle,lem:l20-star-mean} (pair maps, swapped products, star means), with \cref{thm:dl:K}, \cref{lem:matching:kernel} and \cref{lem:paley-triple} (witness kernels and completion counts); \cref{lem:record:weighted-moment} (the fluctuation of the extension count); \cref{lem:restriction} (the actual half); \cref{lem:tilt-marginals} and \cref{prop:matching:positive}(a),(a$'$) (mass, marginal, range and the constant block); \cref{lem:record:root-marginal}(i),(ii) and \eqref{eq:record:root-count} ($R_p$, $\chi^+_p$); \cref{lem:spec:cutkernel}(f) and \cref{lem:spec:tensorcomp}(b) (cut operators of a reweighted law, block caps); \cref{lem:majorant} (evaluation at an endpoint); \cref{lem:record:local-domain} (the block budget). Certificate: \cref{cert:positive-root-caps}. \paragraph{Hypotheses verified in this section (\cref{tab:hypotheses}).} the seven positive-root bands supply the root inputs of ``(CP1) middle'': positivity, support, native sorting symmetries, uniform single-slot marginals, and finite chamber and layer caps. Pair laws use \cref{lem:positive-root-properties}; the coherent law uses the physical dictionary, positive floor and square-affine invariance of \cref{lem:imp:coherent39-law}. Their common finite interfaces and actual marginal data are certified in \cref{cert:positive-root-caps}. The completion is in \cref{sec:middle-frame}; restorations use \cref{lem:record:root-marginal}(iv). \space % End sections/20b_positive_roots % Begin sections/20c_middle_frame \section{Middle primes III: the reference law \texorpdfstring{$\mu$}{mu}, first stage \texorpdfstring{$\lambda$}{lambda}, and its dominator} \label{sec:middle-frame} \paragraph{What this section proves and how to read it.} This section builds $\mu$ (five-type completion of the twelve-label principal law), $\lambda$ (polarization and one-stage replacements), and the law $\Nbr$ dominating $\lambda$ at $\iota$, and proves (CP1)--(CP3) for middle atoms with prices $L_0,B$. Inputs: caps of \cref{sec:middle-reference,sec:positive-roots}. Outputs: $\mu,\lambda,\Nbr$ for \cref{sec:middle-records}. A first reading should follow the three constructions and the (CP1)--(CP3) statements; weight verification is reference material. ``Frame'' in labels below means the package of these three laws together with the records and prices defined with them, as defined in \cref{def:record:frame}. On a middle block the reference (\cref{subsec:middle-reference-law}) is the five-type completion of the twelve-label principal law, which is uniform on the intervals below $2^{30}$ and tilted (\cref{sec:positive-roots}) on the seven intervals from $2^{30}$; its completion weights use the caps of the principal law (\cref{sec:middle-reference,sec:positive-roots}) and of the reference fold record (\cref{lem:old-f-law}). The first stage (\cref{subsec:middle-first-stage}) is obtained by polarization at one chamber cut, which removes the two nonaccepting one-layer fold copies $\operatorname{Diag}_\iota(\Pi^{(1)}_{F_1})$, $\operatorname{Diag}_\iota(\Pi^{(1)}_{F_2})$, and by replacing the one-layer matching copies by accepting laws with the same actual conditional marginals; the two resulting record differences are the tags of (CP2)(b). The law $\Nbr$ (\cref{subsec:middle-gram}) then dominates $\lambda$ at $\iota$ in a $2\times2$ block, giving (CP3), and \cref{subsec:middle-frame-prices} computes the resulting prices $L_0$ and $B$. Later sections build the comparison records on this reference (\cref{sec:middle-records}) and compare them with $\mu$, $\lambda$ and $\Nbr$ through the variance savings (\cref{sec:variance}), the dominating matrices (\cref{sec:envelopes}) and the matching envelopes (\cref{sec:matching-mean}); the closing (\cref{sec:closing}) uses the prices through $B$, $R_{\rm err}$ and $L_0$. The middle reference uses twelve labels, two layers over one chamber coordinate, and is pulled back to the slot array $V$ by ignoring the second chamber coordinate. It is the five-type completion of \cref{lem:five-type} applied to the twelve-label root: folds, matchings, merges and constants are added with weights in powers of $r=b^{-1/2}$ ($b$ the least prime of the block) until every chamber cut is positive, and one-layer copies placed on the reserved diagonal restore positivity at the layer flip $\iota$. On the seven tilted pieces the positive root changes two inputs of the completion, its caps at the chamber cut L20 and at the layer cut L21, both proved in fixed half charts (\cref{rem:root-charts}). (\Cref{sec:history} explains how this completion developed from an earlier version on $216$ slots; nothing here depends on that history.) The comparison law built on this reference need not be reflection positive; it is compared with the first stage $\lambda$ only at $\iota$, through the $2\times2$ block of \cref{subsec:middle-gram}, with symmetric and skew errors priced separately. \emph{Conventions.} In this section $\vartheta_a$ is the chamber cut $\vartheta_{0,a}$ of the first coordinate: the reflection $u_0\mapsto2a-1-u_0$ with plus half $H_a=\{a,a+1,a+2\}$ (indices mod $6$), $a\in\Z/6\Z$. The reserved cut $\iota$ flips the layer $\ell$ and has plus half $V_+=\{\ell=0\}$. For a prime $p$ we write $r=p^{-1/2}$ and $q=1/p$; on a block $\Blk$ with least prime $b=b_{\Blk}$, $r=b^{-1/2}$ and $q=1/b$, while $q_{\Blk}=\prod_{p\in\Blk}p$. The order $\succeq_c$ of cut matrices is that of \cref{def:cc:order}. The pieces, the blocks, the twelve-label graphs and the caps of their cuts are those of \cref{sec:middle-reference,sec:positive-roots}. Every middle block has $\log q_{\Blk}\le L=570$; the local data of a piece are evaluated at its start $X$ and at the local cap $L_{\rm loc}=585$ (\cref{lem:record:local-domain}). \subsection{The reference law of a middle block} \label{subsec:middle-reference-law} Fix a middle block $\Blk$ of a piece starting at $X$, with least prime $b$, $r=b^{-1/2}$ and $q=1/b$. An \emph{object} carries one label of $X_{\Blk}$ per layer. Write $\lambda_{\rm F}=\lambda_{\Blk}(G_{\rm F,2})$ and $\lambda_{\rm E}=\lambda_{\Blk}(G_{\rm E,2})$ for the two-layer $F$ and $E$ laws of three objects $(y_0,y_1,y_2)$, $y_o=(y_{o,0},y_{o,1})$, and $\lambda^{(1)}_{\rm F}$, $\lambda^{(1)}_{\rm E}$ for their one-layer versions. The components of the reference are images of these laws under the patterns of \cref{def:patterns}: the folds $F_0=(0,1,2,2,1,0)$, $F_1=(1,0,0,1,2,2)$ and $F_2=(2,2,1,0,0,1)$ applied to the $F$ law, and the matchings $E_0=(0,1,1,2,2,0)$ and $E_1=(0,0,1,1,2,2)$, the six merges $G_{sk}$ (which use the objects $0,1$) and the two constants $C_0,C_1$ (which use the object $0$) applied to the $E$ law. Under a pattern $\phi$, a configuration $(y_0,y_1,y_2)$ of three objects gives the slot $(u_0,u_1,\ell)$ of $V$ the label $y_{\phi(u_0),\ell}$, whatever $u_1$ is. We write $\Pi_\phi$ ($\Pi_{\phi,\Blk}$ when the block matters) for the resulting image on $X_{\Blk}^V$ of the two-layer law, $\Pi^{(1)}_\phi$ for that of the one-layer law, and $\Pi_{\rm L}$ for the two-layer root of the block pulled back in the same way: the uniform law $\lambda_{\Blk}(G_{\rm L,2})$ on the pieces below $2^{30}$, and on the pieces from $2^{30}$ the positive root $\Gamma_{\Blk,\ulaw}$ of \cref{def:positive-root} with the parameter of the piece; $\Pi^{(1)}_{\rm L}$ is the pullback of the one-layer root $\lambda_{\Blk}(G_{\rm L,1})$, which is not tilted. The five types $\rm L,D,S,R,C$, with multiplicities $1,3,2,6,2$ and degrees $0,1,1,2,3$, are those of \cref{def:patterns}; $\pi_{\mathfrak t,j}$ is the sum of the $j$-layer components of type $\mathfrak t$, of mass equal to the multiplicity. For a law $\kappa$ of one-layer configurations, $\operatorname{Diag}_\iota(\kappa)$ places the same configuration on both layers (the diagonal copy of \cref{lem:commoncut}(i)); it is fixed samplewise by $\iota$. The halves of the components at $\vartheta_0$ are listed in \cref{tab:corner}. \paragraph{Rows.} Let $j\in\{1,2\}$. Under the $j$-layer $E$ law let $\nu$ be the law of one object (in this paragraph $\nu$ is this one-object law, not the comparison law) and $\nu^\xi$ the conditional law of an outer object given that the middle object $y_1$ equals $\xi$: $\nu$ is uniform on the $j$-tuples, indexed by the layers, of block labels whose labels at each prime are pairwise distinct, and $\nu^\xi$ is uniform on those whose labels avoid the labels of $\xi$ at every prime. Let $T^\xi_{\rm F}$ and $T^\xi_{\rm E}$ be the densities, relative to $\nu^\xi\otimes\nu^\xi$, of the conditional law of $(y_0,y_2)$ given $y_1=\xi$ under the $j$-layer $F$ and $E$ laws, regarded as operators on $L^2(\nu^\xi)$. For a prime $p$ let $\rho_{{\rm F},j}(p)$ and $\rho_{{\rm E},j}(p)$ be the Schur-test bounds of \cref{cor:influence-schur} for the conditional maximal correlation of the labels of objects $0$ and $2$, with the labels of object $1$ pinned, under $\lambda_p(G_{{\rm F},j})$ and $\lambda_p(G_{{\rm E},j})$, in the form of \cref{rem:influence-uses}(1) (graded count errors; the two vertex sets of the corollary are the labels of the two outer objects); they are explicit functions of $r=p^{-1/2}$, and $\rho_{{\rm F},j}(X)$, $R_j(X)$ below denote their values at $r=X^{-1/2}$. With $n=L_{\rm loc}/\log X$, $R_1(p)=(p-1)/(p-3)$, $R_2(p)=(p-3)(p-7)/((p-11)(p-15))$ and $\upsilon_j=(e^{n(R_j(X)-1)^2}-1)^{1/2}$, the \emph{row constants} of the piece are \[ f_j=\frac{R_j(X)^n\rho_{{\rm F},j}(X)+2\upsilon_j+\upsilon_j^2}{X^{-1/2}}, \qquad h_j=\frac{\rho_{{\rm E},j}(X)}{X^{-1/2}} . \] These are the row constants that the certificate evaluates (\cref{rem:row-comparison-uses}(1)). \begin{lemma}[The reference]\label{lem:front12:reference} Let $\Blk$ be a middle block of a piece starting at $X$, with least prime $b$ and $r=b^{-1/2}$. \begin{enumerate}[label=(\roman*)] \item \emph{Rows.} For $j\in\{1,2\}$ the middle object has the law $\nu$ under the $j$-layer $F$ law as well as under the $j$-layer $E$ law, and for every value $\xi$, \[ \|T^\xi_{\rm F}-\Jproj\|\le f_jr,\qquad \|T^\xi_{\rm E}-\Jproj\|\le h_jr \] on $L^2(\nu^\xi)$, $\Jproj$ being the projection onto constants. \item \emph{Negative envelopes.} Let $d$, $d_1$, $k_{\rm L}$ and $k_{\rm E}$ be the block caps, at the piece start $X$ and the local cap $L_{\rm loc}$, of the root cuts L20 and L10 and of the layer cuts L21 and E21: for L10 and E21, and for L21 on the pieces below $2^{30}$, those of \cref{lem:layer12-caps}(b); for L20 on the pieces below $2^{30}$ that of \cref{imp:local:collision-gap}; for L20 and L21 on the pieces from $2^{30}$ those of the positive root (\cref{cert:positive-root-caps}). Let $k_{\rm D}=k_{\rm D}(X,L_{\rm loc})$ be the cap of the reference fold record of \cref{lem:old-f-law}(e), and put $k_{\rm S}=k_{\rm R}=k_{\rm C}=k_{\rm E}$. Then \[ \Pi_{\rm L}\succeq_{\vartheta_0}-dr\,\Pi_{F_0},\qquad \Pi^{(1)}_{\rm L}\succeq_{\vartheta_0}-d_1r\,\Pi^{(1)}_{F_0}, \] and $\Pi_\phi\succeq_\iota-k_{\mathfrak t}r\operatorname{Diag}_\iota(\Pi^{(1)}_\phi)$ for every two-layer component $\Pi_\phi$ of type $\mathfrak t$, the root included. \item \emph{Completion.} Let $w=(w_{\rm L},w_{\rm D},w_{\rm S},w_{\rm R},w_{\rm C})$ with $w_{\rm L}=1$ and $v=(v_{\rm L},v_{\rm D},v_{\rm S},v_{\rm R},v_{\rm C})$ be nonnegative weights satisfying the thirteen inequalities \begin{align*} &w_{\rm D}\ge d,&&w_{\rm S}\ge w_{\rm D},&&w_{\rm R}\ge f_2w_{\rm D}+h_2w_{\rm S}, &&w_{\rm C}w_{\rm S}\ge w_{\rm R}^2,\\ &v_{\rm D}\ge d_1v_{\rm L},&&v_{\rm S}\ge v_{\rm D},&&v_{\rm R}\ge f_1v_{\rm D}+h_1v_{\rm S}, &&v_{\rm C}v_{\rm S}\ge v_{\rm R}^2,\\ &v_{\mathfrak t}\ge k_{\mathfrak t}w_{\mathfrak t}\quad(\mathfrak t\in\{\rm L,D,S,R,C\}). \end{align*} Then \[ \widetilde\mu_{\Blk}=\sum_{\mathfrak t}w_{\mathfrak t}r^{\deg\mathfrak t}\pi_{\mathfrak t,2} +r\sum_{\mathfrak t}v_{\mathfrak t}r^{\deg\mathfrak t}\operatorname{Diag}_\iota(\pi_{\mathfrak t,1}) \] is a nonnegative measure on $X_{\Blk}^V$ of mass at least one, reflection positive at every cut of the family (the chamber cuts of both coordinates and $\iota$), and invariant under the layer swap and under the square-affine maps of (R3) of \cref{hyp:record:reference}; in particular its one-slot marginals are its mass times the uniform law. \item \emph{Protection.} If the weights satisfy moreover the fourteenth inequality \begin{equation}\label{eq:protection} v_{\rm D}\ge2k_{\rm D}w_{\rm D}, \end{equation} which implies $v_{\rm D}\ge k_{\rm D}w_{\rm D}$ of the third line, then for $s\in\{1,2\}$ \[ 2w_{\rm D}r\,\Pi_{F_s}+v_{\rm D}r^2\operatorname{Diag}_\iota(\Pi^{(1)}_{F_s}) \succeq_\iota0. \] Parts (i)--(iii) do not use \eqref{eq:protection}; the bracket of \cref{subsec:middle-gram} does. \end{enumerate} The \emph{reference law} of $\Blk$ is $\mu_{\Blk}=\widetilde\mu_{\Blk}/\widetilde\mu_{\Blk}(1)$. It satisfies (R1)--(R3) of \cref{hyp:record:reference}, with (R2) at every cut of the family, and it is admissible (\cref{def:admissible}). \end{lemma} \begin{proof} (i) \emph{One prime.} For one layer the middle law is uniform for both laws, by translation invariance; for two layers it is uniform on the distinct pairs for the $E$ law by symmetry and for the $F$ law by \cref{lem:record:class-three}(ii), since $p\ge Q_3>11$. Under the $E$ law the outer objects given $y_1=\xi$ have exactly the marginal $\nu^\xi$, so $T^\xi_{\rm E}$ is the density of a coupling with exact marginals and $\|T^\xi_{\rm E}-\Jproj\|$ is its conditional maximal correlation, at most $\rho_{{\rm E},j}(p)$ by \cref{cor:influence-schur}. Under the $F$ law the actual outer marginals given $y_1=\xi$ have densities in $[R_j(p)^{-1},R_j(p)]$ relative to $\nu^\xi$ (\cref{lem:record:class-three}(iii), $p>15$), and the coupling relative to these actual marginals has maximal correlation at most $\rho_{{\rm F},j}(p)$; in the language of the four-count comparison (\cref{lem:four-count}), these densities are ratios of completion counts. \emph{The block.} Fix $j\in\{1,2\}$. Given $\xi=(\xi_p)_p$ the conditional laws are products over the primes of $\Blk$. By \cref{lem:row-comparison}(c), the densities of the actual outer marginals multiply, so they are at most $R_{\Blk}=\prod_pR_j(p)\le R_j(b)^n$, because $R_j$ decreases and $|\Blk|\le n_X\le n$ (\cref{lem:record:local-domain}(ii)); their chi-square defects multiply, and a density with values in $[R^{-1},R]$ has defect at most $R-1$; writing $g$ for an outer marginal density and $g_p$ for its factor at $p$, \[ 1+\|g-1\|^2=\prod_p(1+\|g_p-1\|^2)\le\exp\Bigl(\sum_p(R_j(p)-1)^2\Bigr) \le e^{n(R_j(b)-1)^2} \] for each such $g$; and the maximal correlation of the product coupling is the largest of the factors, at most $\max_p\rho_{{\rm F},j}(p)$, respectively $\max_p\rho_{{\rm E},j}(p)$. Hence \cref{lem:row-comparison}(a), with $H_{\rm L},H_{\rm R}\le R_{\Blk}$ and $v_{\rm L},v_{\rm R}\le\upsilon$, $\upsilon^2=e^{n(R_j(b)-1)^2}-1$, gives $\|T^\xi_{\rm F}-\Jproj\|\le R_{\Blk}\max_p\rho_{{\rm F},j}(p)+2\upsilon+\upsilon^2$; the $E$ kernel has exact marginals, so $\|T^\xi_{\rm E}-\Jproj\|\le\max_p\rho_{{\rm E},j}(p)$. \emph{Evaluation at the piece start.} As functions of $r=p^{-1/2}$ (with $n$ fixed), $(R_1-1)/r^2=2/(1-3r^2)$ and $(R_2-1)/r^2=(16-144r^2)/((1-11r^2)(1-15r^2)) =\sum_{m\ge0}(24\cdot15^m-8\cdot11^m)r^{2m}$ are power series with nonnegative coefficients, so $\upsilon/r$ and $\upsilon^2/r=r(\upsilon/r)^2$ are admissible majorant functions in the sense of \cref{lem:majorant} (a different use of \emph{admissible} from admissible laws), since $(e^x-1)/x$ increases; $R_j^n$ is nondecreasing in $r$; and $\rho_{{\rm F},j}/r$, $\rho_{{\rm E},j}/r$ are admissible, the bound of \cref{cor:influence-schur} being $r$ times an admissible function of $r$ (\cref{rem:influence-uses}(3)). Hence $\max_p\rho(p)\le\rho(b)$, and the bound of the previous paragraph, divided by $r$, is a majorant function of $r$, so the bound is at most $r$ times that quotient at $r=b^{-1/2}$, which is at most its value at $X$ by \cref{lem:majorant}(b): $\|T^\xi_{\rm F}-\Jproj\|\le f_jr$ and $\|T^\xi_{\rm E}-\Jproj\|\le h_jr$. (ii) The plus half of $\vartheta_0$ carries the objects $0,1,2$ of $H_0$, and by \cref{lem:layer12-geometry}(b) the half graph of the root at $\vartheta_0$ is $G_{\rm F,2}$, whose labelling law $\lambda_{\rm F}$ is the law of the plus half of $\Pi_{F_0}$. The configurations of $\Pi_{F_0}$ are fixed by $\vartheta_0$ (as $F_0(5-u)=F_0(u)$), so the cut form of $\Pi_{F_0}$ at a real half-function $\Phi$ is $\E_{\lambda_{\rm F}}\Phi^2$. For the uniform root the cut form of $\Pi_{\rm L}$ is $\ip\Phi{\mathsf A_{\Blk}\Phi}$, where $\mathsf A_{\Blk}$ is its cut operator on $L^2(\lambda_{\rm F})$, and \cref{imp:local:collision-gap} for the cut L20 gives the first inequality. For the positive root of a piece from $2^{30}$ the cut form of $\Pi_{\rm L}$ at $\Phi$ is $\ip\Phi{T_{\Blk}\Phi}$ on $L^2(\lambda_{\rm F})$, where $T_{\Blk}$ is the cut operator of the reweighted graph law relative to the fixed half law $\lambda_{\rm F}$ (\cref{lem:spec:cutkernel}(f)); \cref{cert:positive-root-caps} with \cref{lem:spec:tensorcomp}(b) gives $T_{\Blk}\succeq-dr$, which is the first inequality with the same $\Pi_{F_0}$ (\cref{rem:root-charts}). The one-layer root is the uniform law on every piece, and \cref{lem:layer12-caps}(b) for the cut L10 gives the second inequality. At $\iota$, by \cref{lem:layer12-geometry}(c) the half graphs of $G_{\rm L,2}$ and $G_{\rm E,2}$ are their one-layer graphs, and the cut form of $\operatorname{Diag}_\iota(\Pi^{(1)}_\phi)$ at $\Phi$ is the mean of $\Phi^2$ under $\Pi^{(1)}_\phi$. So the caps L21 and E21 give $\lambda_{\Blk}(G_{\rm L,2})\succeq_\iota-k_{\rm L}r\operatorname{Diag}_\iota(\lambda_{\Blk}(G_{\rm L,1}))$ for the uniform root and $\lambda_{\rm E}\succeq_\iota-k_{\rm E}r\operatorname{Diag}_\iota(\lambda^{(1)}_{\rm E})$. For the positive root, the layer bounds of \cref{cert:positive-root-caps} with \cref{lem:spec:cutkernel}(f) and \cref{lem:spec:tensorcomp}(b) give the inequality relative to the half law of $\operatorname{Diag}_\iota(\Pi^{(1)}_{\rm L})$, the untilted one-layer root: $\Gamma_{\Blk,\ulaw}\succeq_\iota -k_{\rm L}r\operatorname{Diag}_\iota(\lambda_{\Blk}(G_{\rm L,1}))$. A component is the image of its field law under an emission, and it inherits the bound of the field law (\cref{lem:five-type}(e)); this gives the inequality for the root and, with $k_{\rm E}$, for the matchings, the merges and the constants. For the folds it is \cref{lem:old-f-law}(e), with the cap $k_{\rm D}=k_{\rm D}(X,L_{\rm loc})$: its values at the $33$ piece starts, with the gates of that lemma, are in \cref{cert:record:old-f-cap}, and its conditions on the block ($p\ge X\ge2^{24}$, $\sum_{p\in\Blk}\log p\le L_{\rm loc}$) hold by \cref{lem:record:local-domain}(i),(ii). (iii) \emph{Positivity, mass and invariance.} All components are probability laws and all weights are nonnegative; the root has weight $w_{\rm L}=1$, so $\widetilde\mu_{\Blk}(1)\ge1$. Every graph law $\lambda_p(G)$ is invariant under the diagonal maps $z\mapsto\alpha z+\beta$ with $\alpha$ a nonzero square, which preserve injectivity and multiply differences by squares; the component maps act on the vertices only and commute with them, and on a block the maps act independently at each prime. The positive root is invariant under the same maps and under the layer swap (\cref{lem:positive-root-properties,lem:imp:coherent39-law}). Translations act transitively, so every one-slot marginal is its mass times the uniform law (\cref{lem:marginals}). The layer swap is an automorphism of the three two-layer graphs (\cref{lem:layer12-geometry}(a)), and a diagonal copy is fixed by it. \emph{First-coordinate cuts.} For $j\in\{1,2\}$, the middle law $\nu$ and the conditional references $\nu^\xi$ of the $j$-layer $E$ law, the two-object marginal of that law, the $j$-layer $E$ and $F$ laws and the $j$-layer root form a five-type datum on the label set of one object (\cref{def:five-type-datum}): the $E$ law is exchangeable; by (i) the middle law of the $F$ law is $\nu$, so that the $F$ law has the form required there with the kernels $T^\xi_{\rm F}$; and the root is invariant under $\mathcal G_6$ (\cref{lem:layer12-geometry}(a) for the uniform root, \cref{lem:positive-root-properties,lem:imp:coherent39-law} for the positive root). For $j=2$, (i) gives the full-norm hypotheses of \cref{lem:five-type}(b) with $e_{\rm F}=f_2r$ and $e_{\rm E}=h_2r$, and (ii) the root envelope with $\delta=dr$; for the graded weights $(1,w_{\rm D}r,w_{\rm S}r,w_{\rm R}r^2,w_{\rm C}r^3)$ the conditions of \cref{lem:five-type}(b) are the four inequalities of the first line. So $\sum_{\mathfrak t}w_{\mathfrak t}r^{\deg\mathfrak t}\pi_{\mathfrak t,2}$ is reflection positive at every chamber cut of the first coordinate. The same holds for $j=1$ with the inputs $d_1,f_1,h_1$ and the weights $v$ (the second line, homogeneous in $v_{\rm L}$), and the diagonal copy preserves this positivity (\cref{lem:five-type}(e)). \emph{The reserved cut.} By (ii) every two-layer component of type $\mathfrak t$ is bounded below at $\iota$ by $-k_{\mathfrak t}r$ times the diagonal copy of its one-layer component, and the third line is $v_{\mathfrak t}\ge k_{\mathfrak t}w_{\mathfrak t}$; so $\widetilde\mu_{\Blk}\succeq_\iota0$ by the fold pairing of \cref{lem:five-type}(e). The one-layer component of a type need not be the one-layer marginal of its two-layer component, only the order of (ii) being used (\cref{lem:five-type}(e)); for the positive root it is the untilted $\Pi^{(1)}_{\rm L}$. The first coordinate and the layer are the active coordinates of the pullback to $V$, so both conclusions hold on $V$ (\cref{lem:slot-array}(v)). \emph{Second-coordinate cuts.} $\widetilde\mu_{\Blk}$ is the pullback of a law on the labels indexed by $(u_0,\ell)$, so every configuration is fixed by every chamber cut of the second coordinate, and the cut matrix there is nonnegative diagonal (\cref{lem:slot-array}(v), \cref{lem:commoncut}). \emph{Normalization} preserves positivity and the marginal assertions, and (R1) holds because the block and its law do not depend on the scale. The reference is a nonnegative law depending only on the labels in the finite fields at the primes of the block, invariant under the maps of (R3); so it has uniform whole-slot marginals and does not depend on the interval, residue or inclusion indices, which is (O1) of \cref{def:admissible}; no sharp bound is claimed for it, so clause (O2) is vacuous for it. (iv) By (ii) for the type D, $2w_{\rm D}r\,\Pi_{F_s}\succeq_\iota-2k_{\rm D}w_{\rm D}r^2 \operatorname{Diag}_\iota(\Pi^{(1)}_{F_s})$, and $\operatorname{Diag}_\iota(\Pi^{(1)}_{F_s})\succeq_\iota0$, being fixed samplewise by $\iota$ (\cref{lem:commoncut}); so \eqref{eq:protection} gives the claim. \end{proof} \begin{remark}[The certified weights]\label{rem:middle-weights} In each of the $33$ pieces the weights $w,v$ are fixed rationals (\cref{tab:data:middle-weights}), chosen at $(X,L_{\rm loc})$ with the caps of the piece, and the thirteen inequalities of \cref{lem:front12:reference}(iii) and the protection \eqref{eq:protection} are checked exactly with the inputs of the piece, $462$ inequalities in all (\cref{cert:record:frame-data}). In every piece three of them fix the leading weights: $w_{\rm D}=w_{\rm S}$ is the block cap $d$ of L20, rounded up; $v_{\rm L}$ is the block cap $k_{\rm L}$ of L21, rounded up; and $v_{\rm D}=v_{\rm S}$ is $2k_{\rm D}w_{\rm D}$, rounded up to the tabulated rational, so that the protection inequality holds, with equality before rounding. The inequality $v_{\rm D}\ge d_1v_{\rm L}$ is slack, also on the seven pieces from $2^{30}$, where $v_{\rm L}$ is the layer cap of the same positive root. Its smallest slack on these seven pieces is greater than $5.7\cdot10^{-5}$; the exact rational check retains this gate along with protection. The certificate checks $v_{\rm S}\ge2k_{\rm E}w_{\rm S}$, which is stronger than required. Since every input of \cref{lem:front12:reference} is evaluated at the piece start and is valid for every block of the piece (\cref{lem:record:local-domain}), one set of weights serves all blocks of a piece. \end{remark} \begin{remark}[The fixed half charts]\label{rem:root-charts} The caps of the positive root are proved in two fixed charts: at the chamber cut on $L^2(\lambda_{\rm F})$, the half law of $\Pi_{F_0}$, and at the layer cut on $L^2(\lambda_{\Blk}(G_{\rm L,1}))$, the half law of $\operatorname{Diag}_\iota(\Pi^{(1)}_{\rm L})$ (\cref{cert:positive-root-caps}). These are the diagonal measures against which \cref{lem:front12:reference}(ii) is stated and which the completion of (iii) uses, so the actual half marginal of the positive root, whose density relative to the fixed half law differs from $1$ by $O(r)$ in the norms used below, is not needed there. Its change is paid where the half marginal enters: in the restorations of the variance credits and of the mean savings (\cref{lem:record:root-marginal}(iv)). \end{remark} Together with the laws of the other ranges (\cref{lem:frontier:iidlocal}, \cref{lem:upper-reference-rp}, \cref{lem:tail-law}), the reference laws of the middle blocks form the reference $\mu=\bigotimes_{\Blk}\mu_{\Blk}$ of (CP1). Of its components, the root and the aligned fold $\Pi_{F_0}$ accept the six queries, both as two-layer components and as one-layer diagonals (the positive root has the support of the uniform root); every other record is removed or replaced, by the first stage below or by the comparison law (\cref{cert:record:middle-geometry}). \subsection{The first stage \texorpdfstring{$\lambda$}{lambda} (polarization and one-stage replacements)}\label{subsec:middle-first-stage} The comparison law will not contain the two one-layer fold records $\operatorname{Diag}_\iota(\Pi^{(1)}_{F_1})$ and $\operatorname{Diag}_\iota(\Pi^{(1)}_{F_2})$, which do not accept the queries, nor the folded matching records in their reference form. The first stage removes them at the price of a second-order correction at one chamber cut, and replaces the folded matching records by laws that accept the queries and keep their actual conditional marginals. \begin{definition}[The middle frame]\label{def:record:frame} The frame consists of the following objects. \begin{enumerate}[label=(\alph*)] \item \emph{Reference.} $\mu=\bigotimes_{\Blk}\mu_{\Blk}$ is the reference of (CP1); on a middle block, $\mu_{\Blk}$ is the law of \cref{lem:front12:reference}. \item \emph{Records.} Let $\Blk$ be a middle block with least prime $b$, and put $r=b^{-1/2}$ and $q=r^2$. Before the common normalization, define the following measures (the first two are summands of $\widetilde\mu_{\Blk}$; the next three are added in (d) below): \begin{itemize} \item $F_{\rm fold}=v_{\rm D}r^2\bigl(\operatorname{Diag}_\iota(\Pi^{(1)}_{F_1}) +\operatorname{Diag}_\iota(\Pi^{(1)}_{F_2})\bigr)$ is the sum of the two nonaccepting one-layer fold components on the reserved diagonal, of mass $2v_{\rm D}r^2$; \item $E_{\rm fold}=v_{\rm S}r^2\bigl(\operatorname{Diag}_\iota(\Pi^{(1)}_{E_0}) +\operatorname{Diag}_\iota(\Pi^{(1)}_{E_1})\bigr)$ is the sum of the two reserved-folded matching components, of mass $2v_{\rm S}r^2$; \item $E_{\rm add}=v_{\rm D}r^2\bigl(\operatorname{Diag}_\iota(\Pi^{(1)}_{E_0}) +\operatorname{Diag}_\iota(\Pi^{(1)}_{E_1})\bigr)$ is a pair of reserved-folded matching records of total mass $2v_{\rm D}r^2$; \item $G=(f_1+h_1)r\,(G_e+G_o)$, with $G_e=v_{\rm D}r^2\operatorname{Diag}_\iota(\Pi^{(1)}_{G_{00}})$ and $G_o=v_{\rm D}r^2\operatorname{Diag}_\iota(\Pi^{(1)}_{G_{11}})$, is the \emph{polarization correction}: two merge records of common record weight $v_{\rm D}r^2$, of total mass $2v_{\rm D}(f_1+h_1)r^3$; \item $H$ adds, for each of the two two-layer matching components $\Pi_{E_0},\Pi_{E_1}$ of weight $w_{\rm S}r$, its actual half diagonal $\operatorname{Diag}_\iota(\Pi^{(1)}_{E_s})$ with coefficient $2w_{\rm S}r\cdot3/(b-3)$; thus $H$ has mass $12w_{\rm S}r^3/(1-3q)$. \end{itemize} All five measures are nonnegative and reserved diagonal, that is, fixed samplewise by $\iota$. In the decompositions below all five measures are divided by $\widetilde\mu_{\Blk}(1)$; only the first two are records of $\mu_{\Blk}$ itself. \item \emph{First stage.} $E_{\rm new}$ is the nonnegative reserved-diagonal replacement of $E_{\rm fold}+E_{\rm add}$ given by \cref{lem:record:one-stage-folded-e}. It has the same mass, it accepts the six queries, and at its own first-coordinate cut ($\vartheta_1$ for $E_0$, $\vartheta_2$ for $E_1$) each record of $E_{\rm new}$ has the same actual conditional marginals as the record it replaces. \item \emph{Decomposition.} Blockwise, and with all records zero outside the middle blocks, \begin{align*} \rho&=\mu-F_{\rm fold}+E_{\rm add}+G,& \lambda&=\mu-F_{\rm fold}-E_{\rm fold}+E_{\rm new}+G,\\ \delta_E&=E_{\rm new}-E_{\rm fold}-E_{\rm add},& \Nbr&=\lambda+F_{\rm fold}+H,\\ \Nbrz&=\mu+E_{\rm add}+G+H. \end{align*} Hence $\lambda=\rho+\delta_E$, $\Nbr=\Nbrz+\delta_E$, $\Nbr-\lambda=F_{\rm fold}+H$ and $\Nbr+\lambda=2\mu-F_{\rm fold}-2E_{\rm fold}+H+2E_{\rm new}+2G$; in particular $F_{\rm fold}$ occurs with coefficient one in $\Nbr-\lambda$. (The bracket measures $\Nbr$ and $\Nbrz$ are unrelated to the scale $N=\Kint\Lsc$.) \item \emph{Prices and tags.} $U_0$ is the summed price of $\Nbrz-\mu=E_{\rm add}+G+H$ and $P$ that of $F_{\rm fold}+E_{\rm add}+G$. The record differences of $\delta_E$ form two tags (\cref{def:cp2}(b)): the differences of type $E_0$, sharp at their first-coordinate cut $\vartheta_1$, form the tag $0$, and those of type $E_1$, sharp at $\vartheta_2$, the tag $1$. $V$ and $D$ are the summed variation and sharp prices of $\delta_E$, the sharp price of a difference being its mass times its sharp bound at its own cut, relative to its actual half marginals, times $q_{\Blk}^{2a}$ (\cref{def:price}(b)). The two tags have equal totals, the sharp total $D/2$ and the variation total $V/2$ each, because the two records of a block have the same mass and the same sharp bound (\cref{lem:record:middle-prices}). With the two-tag series $\tagser$ of \cref{cor:two-cut-series}, \[ R_{\rm err}=e^{U_0}\tagser(D/2,V/2),\qquad B=e^{U_0}+R_{\rm err},\qquad L_0=e^{P}\tagser(D/2,V/2). \] \end{enumerate} \end{definition} The actual half marginal of $\Pi_{E_s}$ at $\iota$ is the uniform law on ordered triples of distinct labels placed by $E_s$, which is the half law of $\Pi^{(1)}_{E_s}$ (\cref{lem:record:fold-identification}(d)); this is the diagonal that $H$ adds. All records in \cref{def:record:frame}(b) are images of invariant laws under vertex maps, followed by a diagonal copy, so they are positive records (\cref{def:cp:records}): their normalizations are admissible. Admissibility of the replacements in \cref{def:record:frame}(c) is verified after \cref{lem:record:one-stage-folded-e} below. \begin{lemma}[The polarized first stage]\label{lem:middle-polarization} For every middle block, $E_{\rm add}+G-F_{\rm fold}\succeq_{\vartheta_0}0$. Hence $\rho_{\Blk}\succeq_{\vartheta_0}\mu_{\Blk}\succeq_{\vartheta_0}0$, and (CP2)(a) holds at the cut $\vartheta_0$, with the variation price $p_{\Blk}$ of the positive records $F_{\rm fold}$, $E_{\rm add}$ and $G$. \end{lemma} \begin{proof} The one-layer data of the proof of \cref{lem:front12:reference}(iii) form a five-type datum whose rows satisfy $\|T^\xi_{\rm F}-\Jproj\|\le f_1r$ and $\|T^\xi_{\rm E}-\Jproj\|\le h_1r$ (\cref{lem:front12:reference}(i) with $j=1$). By \cref{lem:tr:polarization}(a) with $\varepsilon=(f_1+h_1)r$, \[ \Pi^{(1)}_{E_0}+\Pi^{(1)}_{E_1}+(f_1+h_1)r\bigl(\Pi^{(1)}_{G_{00}}+\Pi^{(1)}_{G_{11}}\bigr) \succeq_{\vartheta_0}\Pi^{(1)}_{F_1}+\Pi^{(1)}_{F_2} . \] A diagonal copy preserves this order of cut matrices (\cref{lem:five-type}(e)); multiplying by the record weight $v_{\rm D}r^2$ gives $E_{\rm add}+G\succeq_{\vartheta_0}F_{\rm fold}$ (\cref{rem:polarization-uses}(1)). The reference is positive at $\vartheta_0$ (\cref{lem:front12:reference}), and $\rho_{\Blk}-\mu_{\Blk}$, which is $E_{\rm add}+G-F_{\rm fold}$ divided by $\widetilde\mu_{\Blk}(1)$, is a real combination of the three positive records, of variation at most their total mass. \end{proof} So the first stage costs only second order in $r$ (the removed fold copies have mass $2v_{\rm D}r^2$): the nonaccepting one-layer fold copies are traded for matching records at the one cut $\vartheta_0$ where positivity is needed, and the row errors are paid by merges of degree three. Since only actual components of the reference are subtracted, $\rho$ and $\lambda$ stay nonnegative. The tensor step, $Y_\rho\ge Y_\mu$, is Step~1 of \cref{lem:record:first-stage}. \paragraph{The folded matching records.} For $s\in\{0,1\}$ the folded matching record of type $E_s$ in $E_{\rm fold}+E_{\rm add}$ has mass $(v_{\rm S}+v_{\rm D})r^2$: the one-layer law $\Pi^{(1)}_{E_s}$, uniform on the halves, placed on the reserved diagonal. By \cref{cert:record:middle-geometry}, at its first-coordinate cut ($\vartheta_1$ for $E_0$, $\vartheta_2$ for $E_1$) the label of object~$2$ lies on both sides of the cut (it is \emph{shared}), the labels of objects $0$ and $1$ lie on one side each (they are \emph{private}), and the six queries need exactly the edge $y_0\to y_1$. At one prime (the block statement then follows by tensoring), given the shared label $c$, the private pair is uniform on the ordered distinct pairs of $V_c=\Fp\setminus\{c\}$. Write $V_c^\pm=\{a\in V_c:\chi(a-c)=\pm1\}$, each of size $(p-1)/2$, let $\mathbf M_c$ be the $0/1$ matrix of the relation $a\to a'$ on $V_c$, and $\mathbf M_c^{+-}$ its restriction to $V_c^+\times V_c^-$, extended by zero. \begin{lemma}[One-stage replacement of the folded matching records]\label{lem:record:one-stage-folded-e} Let $p\ge11$ with $p\equiv3\pmod4$, $k=(p-3)/4$, $\kappa^{\rm fold}_p=(1+3r)r/(1-3q)=(\sqrt p+3)/(p-3)$ and \[ k_{\rm new}(p)=\frac{1+5q}{(1-3q)(1+q)}+\frac{qr}{(1-3q)(1-2q)},\qquad s_{\rm fold}(p)=\frac{(1+r)^2+4q}{(1-3q)^2}+\frac q{(1-2q)^2}. \] \begin{enumerate}[label=(\alph*)] \item The four blocks of $\mathbf M_c$, from $V_c^+$ to $V_c^+$, from $V_c^+$ to $V_c^-$, from $V_c^-$ to $V_c^+$ and from $V_c^-$ to $V_c^-$, have equal row and column degrees, namely $k$, $k+1$, $k$ and $k$. \item The matrix $\mathcal K_+=\mathbf M_c/(2k)-\mathbf M_c^{+-}/(2k(k+1))$ is doubly stochastic, supported on the pairs $a\to a'$, with entries $1/(2k)$ or $1/(2(k+1))$ there; from each $a$ it chooses each destination sector with probability $1/2$ and, within a sector, is uniform on the out-neighbours of $a$ in that sector. \item Let $\mathcal K_0=(\Jall-I)/(p-2)$ on $V_c$, the conditional coupling of the record being replaced, and $\Delta=\mathcal K_+-\mathcal K_0$. On $L^2$ of the uniform law of $V_c$ both $\mathcal K_+$ and $\mathcal K_0$ fix constants and preserve mean-zero functions; there $\|\mathcal K_+\|\le\kappa^{\rm fold}_p$ and $\|\mathcal K_0\|=1/(p-2)$; the symmetric part of $\Delta$ has norm exactly $1/(p-2)$, attained at the sector contrast $\one_{V_c^+}-\one_{V_c^-}$; and $\|\Delta\|\le k_{\rm new}(p)\,r$. \item Let $\Blk$ be a block of such primes $p\ge X\ge2^{24}$ with least prime $b$, put $r_X=X^{-1/2}$, $q_X=1/X$, $\alpha_X=(1+3r_X)/(1-3q_X)$ and $\beta_X=1/(1-2q_X)$, write $k_{\rm new}(X)$ and $s_{\rm fold}(X)$ for the displayed formulas evaluated at $q_X,r_X$, and suppose $\alpha_X^2r_X+\beta_X^2q_Xr_X1$ while its left side is below $2^{-11}$. The replaced records are positive records whose normalizations are admissible: they involve only the field labels, and their sharp bounds hold for every value of the shared label, which is (O2) of \cref{def:admissible}. \emph{(CP2)(b).} On a middle block, $\delta_{E,\Blk}=\sum_{s\in\{0,1\}} (\kappa'_s-\kappa_s)$, where $\kappa_s$ is the folded matching record of type $E_s$ in $E_{\rm fold}+E_{\rm add}$ and $\kappa'_s$ its replacement in $E_{\rm new}$: the two have the same mass $(v_{\rm S}+v_{\rm D})r^2$, and by \cref{lem:record:one-stage-folded-e}(e) the difference has a sharp bound $k_{\rm new}(X)b^{-1/2}$ relative to $\kappa_s$ at the cut $\vartheta_{1+s}$, in the sense of \cref{def:price}(b), with the shared label as the label of that definition, and variation at most twice the mass. The difference of type $E_s$ carries the tag $s$ of (CP2)(b), whose cut $\vartheta_{1+s}$ is the same in every middle block. This is (CP2)(b) with two tags, with the sharp and variation prices of \cref{lem:record:middle-prices}; the tag totals are equal. \subsection{The law \texorpdfstring{$\Nbr$}{N} dominating \texorpdfstring{$\lambda$}{lambda} at \texorpdfstring{$\iota$}{iota}}\label{subsec:middle-gram} Hypothesis~(CP3) requires one nonnegative law $\Nbr$ that dominates $\lambda$ at the reserved cut in a $2\times2$ block. The next lemma builds $\Nbr$ from $\mu$ and $\lambda$ record by record and proves that the block is positive semidefinite. \begin{lemma}[The $2\times2$ block dominating $\lambda$ at $\iota$]\label{lem:record:gram} Let the weights of every middle piece satisfy the thirteen inequalities of \cref{lem:front12:reference}(iii) and the protection \eqref{eq:protection}. \begin{enumerate}[label=(\roman*)] \item $\mu\preceq_\iota\Nbrz$, and $\Nbrz-\mu=E_{\rm add}+G+H$ is a nonnegative reserved-diagonal measure. \item $\Nbr=\Nbrz+\delta_E=\lambda+F_{\rm fold}+H$ is a nonnegative measure, $\lambda_{\Blk}$ is symmetric at $\iota$, and blockwise $\begin{pmatrix}\Nbr_{\Blk}&\lambda_{\Blk}\\ \lambda_{\Blk}&\Nbr_{\Blk}\end{pmatrix} \succeq_\iota0$; in particular $-\Nbr\preceq_\iota\lambda\preceq_\iota\Nbr$. \end{enumerate} \end{lemma} \begin{proof} (i) Each of $E_{\rm add}$, $G$ and $H$ is a positive measure fixed samplewise by $\iota$, so its cut matrix is a nonnegative diagonal matrix (\cref{lem:commoncut}), and so is that of their sum $\Nbrz-\mu$. (ii) $\lambda$ is nonnegative: $F_{\rm fold}$ and $E_{\rm fold}$ are actual components of the unnormalized reference, and $E_{\rm new}$ and $G$ are nonnegative. Hence so is $\Nbr=\lambda+F_{\rm fold}+H$. The reference is invariant under the layer swap (\cref{lem:front12:reference}) and all records are reserved diagonal, so the cut matrices of $\lambda_{\Blk}$ and $\Nbr_{\Blk}$ at $\iota$ are symmetric. As in (i), $\Nbr-\lambda=F_{\rm fold}+H\succeq_\iota0$. Next, $\Nbr+\lambda=2\mu-F_{\rm fold}-2E_{\rm fold}+H+2E_{\rm new}+2G$, where $E_{\rm new}$ and $G$ are nonnegative and reserved diagonal; it remains to show $2\mu-F_{\rm fold}-2E_{\rm fold}+H\succeq_\iota0$, and we do so summand by summand in $2\widetilde\mu_{\Blk}$ (all records are divided by the same normalizer $\widetilde\mu_{\Blk}(1)$). Each fold component $\Pi_{F_s}$, $s\in\{1,2\}$, enters $2\widetilde\mu_{\Blk}$ with $2w_{\rm D}r\,\Pi_{F_s}+2v_{\rm D}r^2\operatorname{Diag}_\iota(\Pi^{(1)}_{F_s})$, and $-F_{\rm fold}$ removes one $v_{\rm D}r^2\operatorname{Diag}_\iota(\Pi^{(1)}_{F_s})$; what remains is positive at $\iota$ by \cref{lem:front12:reference}(iv). Each matching component $\Pi_{E_s}$ enters with $2w_{\rm S}r\,\Pi_{E_s}+2v_{\rm S}r^2\operatorname{Diag}_\iota(\Pi^{(1)}_{E_s})$; $-2E_{\rm fold}$ removes its folded part, and $H$ adds $2w_{\rm S}r\cdot3/(b-3)\cdot\operatorname{Diag}_\iota(\Pi^{(1)}_{E_s})$. The component $\Pi_{E_s}$ is uniform on two disjoint injective triples, and its cut operator at $\iota$ relative to its actual half law, the uniform law on injective triples, which is the half law of $\Pi^{(1)}_{E_s}$, is the disjoint-triple operator at each prime; on the block its spectrum lies in $[-3/(b-3),1]$ (\cref{sec:frontier:empty-triple-negative}(c)). Hence $\Pi_{E_s}+\frac3{b-3}\operatorname{Diag}_\iota(\Pi^{(1)}_{E_s})\succeq_\iota0$. Every other component (the root, the aligned fold $\Pi_{F_0}$, the merges and the constants) keeps both its two-layer part and its folded part, which are positive together at $\iota$ by \cref{lem:front12:reference}(ii) and the third line $v_{\mathfrak t}\ge k_{\mathfrak t}w_{\mathfrak t}$ of \cref{lem:front12:reference}(iii). So $2\mu-F_{\rm fold}-2E_{\rm fold}+H\succeq_\iota0$, and $\Nbr_{\Blk}\pm\lambda_{\Blk}\succeq_\iota0$, which is the block statement for the symmetric matrices: conjugation by the unitary $2^{-1/2}\bigl(\begin{smallmatrix}1&1\\1&-1\end{smallmatrix}\bigr)$ turns the block matrix into the diagonal matrix with blocks $\Nbr_{\Blk}+\lambda_{\Blk}$ and $\Nbr_{\Blk}-\lambda_{\Blk}$ (\cref{def:cp3}). Outside the middle, $\Nbr_{\Blk}=\lambda_{\Blk}=\mu_{\Blk}\succeq_\iota0$. \end{proof} With the price $u_{\Blk}$ of $\Nbr_{0,\Blk}-\mu_{\Blk}$ given by \cref{lem:record:middle-prices}, the lemma is hypothesis (CP3) of \cref{thm:comparison} (\cref{def:cp3}). The energy bound that the bracket buys (every structured energy of a fixed selected law with $\Nbr$ outside is at most $B+o(1)$ times its price times $Y$, the part without record differences costing at most $e^{U_0}$ and the rest at most $R_{\rm err}$) is \cref{lem:bracket-energy}, which assumes only (CP1), (CP2)(b), (CP3) and (CP8). \begin{remark}[What the bracket buys]\label{rem:middle-bracket} The bracket is a Gram bracket at $\iota$, not a domination at every cut: the comparison law built later need not be reflection positive, and the comparison is made at the reserved cut only. Two features of the comparison rest on this. First, $\lambda_{\Blk}$ is symmetric at $\iota$, so in the expansion of $Y_\nu-Y_\lambda$ every tensor term with an odd number of skew factors is skew-adjoint and has zero real quadratic form on the identical reserved half-functions; this is why the reserved cost is $B(e^S\cosh A-1)$ and not $B(e^{S+A}-1)$, where $S$ and $A$ are the total symmetric and skew prices of \cref{lem:record:record-expansion}. Second, the conductors of the index supports are held fixed through every Cauchy--Schwarz step: for complementary fold maps $f_+,f_-$ and every slot-weight vector $w=(w_v)$, $\frac12(\sum_vw_{f_+(v)}+\sum_vw_{f_-(v)})=\sum_vw_v$, so although a later chamber fold can give four occurrences of a conductor on one energy and none on the other, their geometric mean has the original two; only after the complementary energies are combined are the conductor powers averaged. The conductor moment of the matching term is therefore exactly $R_I^6$, also in the mixed-cut remainder of \cref{lem:bracket-energy} (\cref{lem:record:folded-energy}(e)). The bracket carries one copy of the one-layer folded copies of the fold records, so that $\Nbrz-\mu=E_{\rm add}+G+H$, whose coefficient of $r^2$, namely $2v_{\rm D}$, is half that of the first-stage records $F_{\rm fold}+E_{\rm add}$ (\cref{lem:record:middle-prices}). Its part $E_{\rm add}+H$ is invariant under the chamber reflections and the group $\mathcal G_6$ they generate, as $\mu$ is, and the positive envelopes use $\mu+E_{\rm add}+H$ as their invariant background (\cref{lem:oct24:invariant-background}). The price is the protection \eqref{eq:protection}, binding in every piece (\cref{rem:middle-weights}), and the diagonal copy of the fold records available to the joint Gram bound of the matching envelopes has coefficient $v_{\rm D}$ per side (\cref{prop:record:matching}). \end{remark} \subsection{Prices \texorpdfstring{$L_0$}{L\_0} and \texorpdfstring{$B$}{B} for \texorpdfstring{$\lambda$}{lambda} and \texorpdfstring{$\Nbr$}{N}} \label{subsec:middle-frame-prices} \begin{lemma}[Middle prices]\label{lem:record:middle-prices} Let $\Blk$ be a block of a middle piece starting at $X$, with least prime $b\ge X$ and $r=b^{-1/2}$. Evaluate every local coefficient below at $X$. Then the prices of $\Blk$ are at most $q_{\Blk}^{2a}$ times \begin{align*} &\Nbrz-\mu:\ 2v_{\rm D}r^2+\Bigl(2v_{\rm D}(f_1+h_1)+\frac{12w_{\rm S}}{1-3/X}\Bigr)r^3,\\ &F_{\rm fold}+E_{\rm add}+G:\ 4v_{\rm D}r^2+2v_{\rm D}(f_1+h_1)r^3,\\ &\delta_E\ \text{(sharp)}:\ 2(v_{\rm S}+v_{\rm D})k_{\rm new}(X)\,r^3,\qquad \delta_E\ \text{(variation)}:\ 4(v_{\rm S}+v_{\rm D})r^2, \end{align*} where $k_{\rm new}$ is the coefficient of \cref{lem:record:one-stage-folded-e}; each of the two tags carries half of the last two prices. \end{lemma} \begin{proof} Dividing by the normalizing mass $\widetilde\mu_{\Blk}(1)\ge1$ only decreases each mass, so it suffices to bound unnormalized masses. The masses of $E_{\rm add}$, $G$ and $H$ (\cref{def:record:frame}(b)) give the first price and those of $F_{\rm fold}$, $E_{\rm add}$ and $G$ the second, with $3/(b-3)=3r^2/(1-3q)\le3r^2/(1-3/X)$. The two prices of $\delta_E$ are those of (CP2)(b) above: two record differences, each of a record of mass $(v_{\rm S}+v_{\rm D})r^2$, with sharp bound $k_{\rm new}(X)r$ and variation at most twice that mass, and no coincidence term; each tag consists of one of them. The row constants $f_1,h_1$ and the coefficient $k_{\rm new}$ are valid at every block of the piece when evaluated at $X$ (\cref{lem:record:local-domain}(iii)). \end{proof} Summing over the blocks of each piece with the charges $b_d(X,Y)$ of \cref{lem:record:block-charge} for a piece $[X,Y)$, writing $b_2,b_3$ for $b_2(X,Y),b_3(X,Y)$ below, and over the $33$ pieces, with the weights and row constants of each piece, \begin{gather*} U_0\le\sum_{\rm pieces}\Bigl[2v_{\rm D}b_2+\Bigl(2v_{\rm D}(f_1+h_1) +\frac{12w_{\rm S}}{1-3/X}\Bigr)b_3\Bigr],\qquad P\le\sum_{\rm pieces}\bigl[4v_{\rm D}b_2+2v_{\rm D}(f_1+h_1)b_3\bigr],\\ D\le\sum_{\rm pieces}2(v_{\rm S}+v_{\rm D})k_{\rm new}(X)\,b_3,\qquad V\le\sum_{\rm pieces}4(v_{\rm S}+v_{\rm D})\,b_2 , \end{gather*} each tag carrying half of $D$ and of $V$. In the certificate arithmetic all coefficients have nonnegative lower endpoints in every piece, so upper charges times upper coefficients are upper bounds. The certificate evaluates these sums from \path{research/push_2026_10_25/global/refined_L570_source.json}, with exact finite block histograms and outward analytic charges, at the anchor exponent $a_0=\PushAnchor$ at which the middle prices are tabulated (\cref{cert:record:middle-price}): the totals there (primed, denoting evaluation at $a_0$) have the upper ends $U_0'\le0.8469081935391430$, $P'\le1.6936504653996420$, $D'\le4.741704122563\cdot10^{-5}$ and $V'\le3.387253370148178$, and each of the two tags has sharp total at most $D'/2$ and variation total at most $V'/2$; the four sums of each piece are listed in \cref{tab:record:middle-charges}. At the baseline exponent $a$ every middle block has $\log q_{\Blk}\le L=570$ (\cref{lem:record:local-domain}(ii)), so all these prices are at most $t=e^{2(a-a_0)L}$ times their values at $a_0$ (\cref{lem:record:repricing}), and \cref{cor:first-stage-repricing} with the two-tag series of \cref{cor:two-cut-series} at $n=4$ gives $U_0<0.846908245753$, $B<2.332628665480$, $R_{\rm err}<2.042558854365\cdot10^{-4}$ and $L_0<4.763323725665\cdot10^{-4}$ (\cref{def:closing-quantities}(2)); the repriced tag totals, about $2.37\cdot10^{-5}$ (sharp) and $1.694$ (variation), satisfy the hypotheses of that corollary, since the sharp total is below the variation total and below $6$, and their product is below $36$. For comparison, the one-sharp bounds $De^{P+V}$ and $De^{U_0+V}$ of \cref{rem:cp:tags} would be about $7.7\cdot10^{-3}$ and $3.3\cdot10^{-3}$: in the tagged series a term whose differences all carry one tag pays no variation price, and a term with both tags pays the variation of the less frequent tag only. The prices of the comparison records of the middle range are those of \cref{lem:middle-comparison-prices}, assembled from \cref{prop:signed-bounds,lem:oct24:matching-star,lem:record:exact-marginal-e,lem:merge-repair} with the same block charges. \paragraph{Consequences and what to read next.} This section depends on the following statements, grouped by topic. \Cref{lem:record:class-three}, \cref{lem:record:local-domain} and \cref{lem:record:block-charge} (pairs, domain and charges); \cref{lem:layer12-geometry} (the half graphs and the symmetries); the caps of the root: \cref{lem:layer12-caps,imp:local:collision-gap,cert:positive-root-caps}, with \cref{lem:spec:cutkernel}(f) and \cref{lem:spec:tensorcomp}(b); \cref{def:positive-root} and \cref{lem:positive-root-properties,lem:imp:coherent39-law}; \cref{lem:old-f-law} (the cap $k_{\rm D}$); \cref{prop:middle-negative} in the form of \cref{cor:influence-schur}, \cref{lem:row-comparison}, \cref{lem:four-count}, \cref{lem:sector} and \cref{lem:majorant} (the rows, the block steps and the evaluation at the piece start); \cref{lem:five-type} with \cref{lem:slot-array}, \cref{lem:marginals}, \cref{lem:commoncut} and \cref{lem:record:fold-identification} (the completion); \cref{lem:tr:polarization} (the first stage); \cref{lem:paley-triple} and \cref{lem:square-shift} (the one-stage repair); \cref{sec:frontier:empty-triple-negative} (the coefficient of $H$); \cref{def:cp2,def:cp3,cor:two-cut-series} (the tags and the series); \cref{lem:record:repricing} and \cref{cor:first-stage-repricing} (prices at $a$). Certificates: \cref{cert:record:middle-price,cert:layer12-grid,cert:l20-grid,cert:positive-root-caps,cert:record:one-stage,cert:record:old-f-cap,cert:record:frame-data,cert:record:middle-geometry}. \paragraph{Hypotheses verified in this section (\cref{tab:hypotheses}).} (CP1) for the middle atoms, that is, (R1)--(R3) with (R2) at every cut of the family (\cref{lem:front12:reference}); (CP2)(a) at $\vartheta_0$ (\cref{lem:middle-polarization}) and (CP2)(b) with two tags (\cref{lem:record:one-stage-folded-e}, \cref{cert:record:one-stage}); (CP3) (\cref{lem:record:gram}, under the protection \eqref{eq:protection}); the prices $P$, $V$, $D$, $U_0$ and the tag totals (\cref{lem:record:middle-prices,lem:record:block-charge,cert:record:middle-price}, \cref{lem:record:repricing}); and the admissibility clause (CP8)(a) for the reference, the first-stage records and the bracket records. These are the rows ``(CP1) middle'', ``(CP2)(a)'', ``(CP2)(b)'', ``(CP3)'' and ``$P$, $V$, $D$, $U_0$, tags'' of \cref{tab:hypotheses}. \space % End sections/20c_middle_frame % Begin sections/21_middle_records \section{Middle primes IV: the comparison law \texorpdfstring{$\nu$}{nu} and its prices \texorpdfstring{$S,A$}{S,A}} \label{sec:middle-records} \paragraph{What this section proves and how to read it.} This section proves (CP4) for middle atoms: it constructs $\nu$ from $\lambda$ by keeping forcing records, replacing non-forcing records at fixed actual marginals, and deleting the rest, and bounds symmetric and skew prices $S,A$. A \emph{record} is one summand (see \cref{subsec:intro:glossary}); $F_0,F_1,F_2$ are fold records (two-layer, defined below) and $E_0,E_1$ matching records. The key idea is mirror pairing: adding a required edge together with its mirror makes the first-order change purely skew. Inputs: \cref{sec:middle-frame}. Outputs: middle contributions to $S,A$ for \cref{sec:closing}. A first reading should follow the keep/replace/delete classification and mirror pairing; per-prime kernel estimates are reference material. On a middle block the comparison law keeps the two-layer root and the aligned fold $F_0$, which accept the six queries, and changes the other two-layer records: the fold records $F_1,F_2$ are replaced by the signed whole-block fold record of parameter $\tlaw$ (\cref{subsec:oct24:pure-local,subsec:pure-bounds}), a combination of mass one of three positive accepting product laws, each with the exact actual half marginals of the record it replaces; the matching records $E_0,E_1$ by the exact-marginal law $K_1$ (\cref{subsec:record:e_side}); the six merge records by their actual-marginal mirror repairs (\cref{subsec:merge-repair}); the two-layer constants by strict Paley-edge laws. The folded merges and constants and the polarization correction $G$ of the first stage are deleted. Every replacement keeps the actual half marginals at $\iota$ of the record it replaces, so every record difference annihilates the constants on both sides of the reserved cut, and every deleted record is positive. \Cref{lem:middle-comparison-prices} collects the symmetric, skew and auxiliary prices of a block; they enter $S$, $A$ and the class bounds as sums over the pieces of the degree charges times local coefficients evaluated at the piece start. Later sections use more than the prices: the three-arm leading stars and remainders of the fold changes and the one-arm stars and degree-four remainders of the matching changes (\cref{prop:signed-bounds,lem:oct24:matching-star}) are the inputs of the positive envelopes (\cref{thm:envelopes}); the coefficient $d_\tlaw$ of the joint Gram matrix for the reference and signed records (\cref{prop:signed-bounds}(d)) is the input of the matching sides (\cref{prop:signed-sides}); the negative cap $k_{\rm D}$ (\cref{lem:old-f-law}(e)) enters the completion (\cref{lem:front12:reference}); and the centred norm $\kappa_F$ of the reference fold record (\cref{lem:record:old-f-marginal}) is an input of the variance credits (\cref{sec:variance}). The idea of the section is a signed pairing of the fold records. The reference fold record has the two cross edges $x_0\to y_2$ and $y_0\to x_2$ between its layer-zero labels $x$ and its layer-one labels $y$, and the queries need one more, $x_1\to y_0$. Adding it alone would change the record at first order in its symmetric and in its skew part. Adding it together with the mirror edge $x_0\to y_1$ (the reversal of its image $y_1\to x_0$ under the reserved reflection) makes the first-order change purely skew, a two-arm star of norm about $\sqrt2\,r$, and pushes the symmetric change to second order: this is the mirror pairing (\cref{subsec:mirror}). The signed record adds two further product laws with coefficients $\pm\tlaw/2$, the signed sum being taken after the products over the primes of the block. The first-order change stays purely skew and becomes a three-arm star of norm about $(1+\tlaw^2+(1-\tlaw)^2)^{1/2}r$ (about $1.2732\,r$ at $\tlaw=127/500$), at the price of a total variation $1+\tlaw$ per block, whatever the number of primes; \cref{rem:mirror-why} explains the trade. Two inputs about the reference fold record are exact rather than perturbative: the pair laws of its actual half marginal (\cref{lem:actual-features}), and a centred bound for its coincidences, which also lowers its negative cap (\cref{lem:old-f-law}(e),(f)). \subsection{One prime: halves, kernels and channels} \label{subsec:middle-records:notation} Throughout the section $p\equiv3\pmod4$ is a prime, $p\ge19$ unless a larger bound is stated (every middle prime is at least $Q_3=19951586>2^{24}$; the statements below that need $p\ge2^{20}$ or $p\ge2^{24}$ say so), and \[ q=\frac1p,\quad r=p^{-1/2},\quad Z=(1-q)(1-2q),\quad h_0=1-14q,\quad e_0=\frac{2q}{(1-3q)(1-4q)},\quad k_p=\frac{p-3}4 . \] Let $\chi$ be the quadratic character and write $a\to b$ if $\chi(b-a)=1$; as $\chi(-1)=-1$ this is a tournament. Finite sets carry their uniform probability and $\E$ is the corresponding average; $H_0$ is the space of mean-zero functions on $\Fp$, $P$ the Paley operator $(Ph)(s)=\E_t\chi(t-s)h(t)$, so $P^*=-P$, $P\one=0$ and $P^*P=qI$ on $H_0$, and $\mathcal G_p$ the group of the maps $t\mapsto\alpha t+\beta$, $\alpha$ a nonzero square, acting diagonally on tuples of labels (\cref{lem:paley-triple}). \paragraph{Halves and kernels.} A \emph{half} is a triple $x=(x_0,x_1,x_2)$ of distinct labels. Let $H_F$ be the set of halves with $x_0\to x_2$, so $|H_F|=p(p-1)(p-2)/2$, and $\nu_F$ its uniform law; its coordinates are uniform, $V_i\colon L^2(\Fp)\to L^2(\nu_F)$, $(V_ih)(x)=h(x_i)$, is an isometry and $V_i^*$ is the conditional expectation onto $x_i$ (\cref{lem:paley-triple}(d)). At the reserved cut a two-layer fold record of a middle block is, at one prime, a probability measure on $H_F\times H_F$: the first half carries the layer-zero labels $x$ of the three objects and the second the layer-one labels $y$ (\cref{lem:record:fold-identification}(b),(d)). We identify such a measure with its density $K(x,y)$ relative to $\nu_F\otimes\nu_F$ and with the operator $Kf(x)=\E_yK(x,y)f(y)$ on $L^2(\nu_F)$; every function on $H_F\times H_F$ is regarded as such a kernel, and $\|\cdot\|$ is the operator norm on $L^2(\nu_F)$ unless another space is named. The reserved reflection exchanges $x_i$ and $y_i$; it maps $K$ to $K^\top(x,y)=K(y,x)$, the adjoint operator. Put $\operatorname{Sym}K=\frac12(K+K^\top)$, $\operatorname{Skew}K=\frac12(K-K^\top)$ and $\Pi_\perp=I-\Jproj$. If $m=g\nu_F$ is a probability measure with $g\ge1-\eta$ for some $\eta\in[0,1)$, the \emph{operator of $K$ on $L^2(m)$} has the same bilinear form, $\ip{\varphi}{K_m\psi}_m=\int\varphi(x)K(x,y)\psi(y)\,d\nu_F(x)\,d\nu_F(y)$; by \cref{lem:record:actual-correlation}(b) its norm is at most $\|K\|/(1-\eta)$, and its symmetric and skew parts are those of $K$, transported in the same way. If $K,K'$ are densities of probability measures with both half marginals $m$, the operator of $K'-K$ on $L^2(m)$ is the operator $\Delta$ of the charging rule \cref{rem:cp:charging}(ii) for the replacement of $K$ by $K'$; the same holds when $K'$ is a signed density of mass one with both half marginals $m$. \paragraph{The Paley channels.} The cross characters of a pair of halves are \begin{equation}\label{eq:middle:channels} \mathsf A=\chi(y_2-x_0),\qquad\mathsf B=\chi(x_2-y_0),\qquad \mathsf C=\chi(y_0-x_1),\qquad\mathsf D=\chi(y_1-x_0); \end{equation} on six distinct labels $\mathsf A=1$, $\mathsf B=1$, $\mathsf C=1$ and $\mathsf D=1$ mean $x_0\to y_2$, $y_0\to x_2$, $x_1\to y_0$ and $x_0\to y_1$. Let $I_\times$ be the indicator that $x$ and $y$ have no common label. Since $\chi(-1)=-1$, transposition acts by \begin{equation}\label{eq:middle:transpose} (\mathsf A,\mathsf B,\mathsf C,\mathsf D)^\top =(\mathsf B,\mathsf A,-\mathsf D,-\mathsf C),\qquad I_\times^\top=I_\times . \end{equation} Kernels below are defined at every pair of halves; a channel whose two labels coincide vanishes there. The edges of $\mathsf A$ and $\mathsf D$ form a star at $x_0$ with leaves $y_2,y_1$, and those of $\mathsf B$ and $\mathsf C$ a star at $y_0$ with leaves $x_2,x_1$; the two stars have no common label. A monomial in the channels is a \emph{star monomial} if all its edges lie in one star ($\mathsf A$, $\mathsf B$, $\mathsf C$, $\mathsf D$, $\mathsf A\mathsf D$, $\mathsf B\mathsf C$) and a \emph{nonstar} otherwise; the nine nonstars are listed in \cref{lem:record:projected-nonstar}. This two-star picture organizes all the estimates of the fold records: star monomials have norms of order $r$, and nonstars, which contain two disjoint cross edges, of order $q$. \paragraph{Features.} For the operators $A_1=V_2P$, $A_2=V_1P$ and $(A_3h)(x)=-\E_s[\chi(s-x_2)\chi(s-x_1)h(s)]-q\E h$ of \cref{lem:paley-triple}(e), the kernels of $A_1V_0^*$, $A_2V_0^*$ and $A_3V_0^*$ are $-\mathsf B$, $\mathsf C$ and $\mathsf B\mathsf C-q$, since they depend on $y$ only through $y_0$, which is uniform; transposing, $\mathsf A=-V_0A_1^*$ and $\mathsf D=-V_0A_2^*$. Put $A_\star=A_2+A_3$ and, for $0\le\tlaw\le1$, \[ A_\tlaw=A_2+\tlaw A_1+(1-\tlaw)A_3,\qquad \mathbf a_\tlaw=(\tlaw,1,1-\tlaw),\qquad |\mathbf a_\tlaw|^2=1+\tlaw^2+(1-\tlaw)^2, \] so that $A_\tlaw=A_{\mathbf a_\tlaw}$ in the notation of \cref{lem:paley-triple}(e), with the \emph{arm vector} $\mathbf a_\tlaw$, and $A_0=A_\star$. The actual half marginal $m_0=g_0\nu_F$ of the reference fold record (\cref{lem:old-f-law}(a)) is translation invariant, so its coordinates are uniform and $V_i$ is also an isometry $H_0\to L^2(m_0)$; write $V_{i,m}^*$ for its adjoint in $L^2(m_0)$, $\mathcal H_i=V_iH_0$, and $\mathcal K_{12}$ for the orthogonal complement in $L^2(m_0)$ of $\mathcal H_1+\mathcal H_2$ within the $m_0$-mean-zero functions of $(x_1,x_2)$. The operator $A_3$ maps $H_0$ into the latter space, because $s\mapsto\E_{m_0}[\chi(s-x_2)\chi(s-x_1)]$ is translation invariant, hence constant. Put $A_3^\circ=\Pi_{\mathcal K_{12}}A_3$, $A_\star^\circ=A_2+A_3^\circ$ and $A^\circ_\tlaw=A_2+\tlaw A_1+(1-\tlaw)A_3^\circ$; the three arms $A_2$, $\tlaw A_1$ and $(1-\tlaw)A_3^\circ$ of $A^\circ_\tlaw$ map into $\mathcal H_1$, $\mathcal H_2$ and $\mathcal K_{12}$, and $A^\circ_0=A^\circ_\star$. \begin{lemma}[Two-feature spectral calculation]\label{lem:two-feature-spectrum} Let $V\colon H_0\to\mathcal H$ be an isometry and $A\colon H_0\to\mathcal H$ satisfy, for real $a,b,c$, \[ V^*A=aI+bP,\qquad A^*A=cI, \] where $P^*=-P$ and $P^*P=qI$ on $H_0$, and $r=\sqrt q$. Then $\delta=c-a^2-b^2q\ge0$, and \begin{align*} \|AV^*+VA^*\|&=|a|+\sqrt{c-b^2q},\\ \|AV^*-VA^*\|&=|b|r+\sqrt{c-a^2}. \end{align*} The spectrum of $AV^*+VA^*$ is contained in $\{0,a\pm\sqrt{c-b^2q}\}$. Thus one pair of Gram identities determines both the symmetric reference spectrum and the skew spectrum of a mirror or signed star, in whichever half-marginal Hilbert space the identities hold. \end{lemma} \begin{proof} Put $M=V^*A$ and $A_\perp=A-VM$. Then $V^*A_\perp=0$ and $A_\perp^*A_\perp=A^*A-M^*M=\delta I$, proving $\delta\ge0$. If $\delta>0$, write $A_\perp=\sqrt\delta\,U$, with $U$ an isometry orthogonal to $V$. Both operators vanish off $VH_0\oplus UH_0$, and on this sum they are \[ AV^*+VA^*=\begin{pmatrix}2aI&\sqrt\delta I\\\sqrt\delta I&0\end{pmatrix}, \qquad AV^*-VA^*=\begin{pmatrix}2bP&-\sqrt\delta I\\\sqrt\delta I&0\end{pmatrix}. \] The first matrix has eigenvalues $a\pm\sqrt{a^2+\delta}$. On a $P$-eigenspace of eigenvalue $i\varepsilon r$, $\varepsilon\in\{\pm1\}$, the second has eigenvalues $i(b\varepsilon r\pm\sqrt{b^2q+\delta})$; its norm is $|b|r+\sqrt{b^2q+\delta}$. Substitution gives the formulas. If $\delta=0$, then $A=VM$, and the operators on $VH_0$ are $2aI$ and $2bP$; the same conclusions hold directly. \end{proof} \paragraph{The reflected transpose.} The map $\varsigma(x)=(-x_2,-x_1,-x_0)$ is an involution of $H_F$ preserving $\nu_F$: the relation $s\to t$ becomes $-t\to-s$ under negation, so $x_0\to x_2$ is preserved, and $\one[x_0\to x_1]$ and $\one[x_1\to x_2]$ are exchanged. Put $(\mathcal Uf)(x)=f(\varsigma x)$, a self-adjoint unitary on $L^2(\nu_F)$, and call $K^\varsigma(x,y)=K(\varsigma y,\varsigma x)$ the \emph{reflected transpose} of a function $K$ on $H_F\times H_F$. As operators $K^\varsigma=\mathcal UK^\top\mathcal U$. The map $(x,y)\mapsto(\varsigma y,\varsigma x)$ preserves $\mathsf A$, $\mathsf B$ and $I_\times$, and $\mathsf C^\varsigma=\chi(y_1-x_2)$. Only this arithmetic identification of coordinates is used; no negation invariance of an input function is assumed. \subsection{The reference fold record at the reserved cut}\label{subsec:old-f} Before the fold records $F_1,F_2$ can be replaced, the record they replace must be understood exactly: the reference's own two-layer fold record at the reserved cut. At one prime this is the uniform law on pairs of halves $(x,y)$ with six distinct labels and the two cross edges $x_0\to y_2$ and $y_0\to x_2$ (the channels $\mathsf A$ and $\mathsf B$ of \eqref{eq:middle:channels}). The next lemma collects everything later sections use about it: how many completions $y$ each half $x$ has and the resulting normalizing constant and actual half marginal; an exact spectral description of its leading part; its centred norms and remainder in the actual marginal; and its negative cap $k_{\rm D}$ at $\iota$, which enters the completion inequality $v_{\rm D}\ge k_{\rm D}w_{\rm D}$ of \cref{lem:front12:reference} and the protection inequality \eqref{eq:protection}. The exact pair laws of its actual half marginal follow in \cref{lem:actual-features}. \begin{lemma}[The reference fold record]\label{lem:old-f-law} Let $p\ge19$, $\Psi_0=I_\times(1+\mathsf A)(1+\mathsf B)$, $z_0=\E\Psi_0$ (the average over $\nu_F\otimes\nu_F$) and $K_0=\Psi_0/z_0$. On six distinct labels $\Psi_0$ is $4$ times the indicator of $x_0\to y_2$ and $y_0\to x_2$, and it vanishes elsewhere; so $K_0$ is uniform on the pairs of halves with six distinct labels, $x_0\to y_2$ and $y_0\to x_2$. It is the law at $\iota$ of each two-layer fold record $\Pi_{F_0},\Pi_{F_1},\Pi_{F_2}$ of the middle reference at one prime (\cref{lem:record:fold-identification}). \begin{enumerate}[label=(\alph*)] \item \emph{Fibres and normalizer.} For $x\in H_F$ put $e_{01}=\one[x_0\to x_1]$ and $e_{12}=\one[x_1\to x_2]$. The number of $y$ with $\Psi_0(x,y)\ne0$ is $N_0(x)=(p-5)(k_p-1)\bigl(\frac{p-3}2-e_{01}-e_{12}\bigr)$, and as $\Psi_0^\top=\Psi_0$ the same formula counts the $x$ for a given $y$. Both half marginals of $K_0$ equal $m_0=g_0\nu_F$, where $g_0\circ\varsigma=g_0$, \[ g_0=\frac{(p-2)(p-3-2e_{01}-2e_{12})}{(p-3)(p-4)},\qquad \|g_0-1\|_\infty=\eta_F:=\frac{2(p-1)}{(p-3)(p-4)} =\frac{2q(1-q)}{(1-3q)(1-4q)}\le e_0, \] the largest value of $g_0$ is $(p-2)/(p-4)=1+2/(p-4)$, and, with $h_0\le z_0\le1$, \[ z_0=\frac{(p-3)(p-4)(p-5)(p-7)}{p(p-1)(p-2)^2} =1-14q+\frac{q^2(53-273q+364q^2)}{(1-q)(1-2q)^2}. \] On a block $\Blk$ of at most $n$ primes $p\ge X$ the density of $m_{0,\Blk}=\bigotimes_pm_{0,p}$ relative to $\nu_{F,\Blk}=\bigotimes_p\nu_{F,p}$ is at most $(1+e_0(X))^n\le e^{ne_0(X)}$, and at most $(1-ne_0(X))^{-1}$ if $ne_0(X)<1$, where $e_0(X)$ denotes $e_0$ evaluated at $q=1/X$. \item \emph{Leading part.} As kernels $\Psi_0=\Jproj+\mathsf L+\mathsf A\mathsf B-\mathsf C_{\rm rem}$, with $\mathsf L=\mathsf A+\mathsf B$ and $\mathsf C_{\rm rem}=(1-I_\times)(1+\mathsf A)(1+\mathsf B)$. On $L^2(\nu_F)$: \begin{enumerate}[label=(\roman*)] \item $\mathsf L$ annihilates the constants and has its spectrum in $\{0\}\cup\{q/(1-q)\pm(q-q^3/(1-q)^2)^{1/2}\}$; hence $\mathsf L\succeq-(r-q)I$ and $\|\mathsf L\|\le r+q/(1-q)\le\Gamma r$, where $\Gamma=1+\varrho+\varrho'$, $\varrho=r\sqrt{1+q}/(1-q)$ and $\varrho'=q(1+\varrho)/(1-2q)$ (\cref{lem:paley-triple}(d)); \item $\|\mathsf A\mathsf B\|\le2q/(1-q)\le2q/Z$; \item $\mathsf C_{\rm rem}$ is nonnegative and symmetric, its row sums are at most $q(17-120q+247q^2)/Z\le17q$, and $\|\mathsf C_{\rm rem}\|\le17q\le17q/Z\le36q$. \end{enumerate} \item \emph{Centred norms.} $\|\Pi_\perp K_0\Pi_\perp\|\le h_{\rm old}/h_0$ with $h_{\rm old}=\Gamma r+(2/Z+36)q$, and on the $m_0$-centred functions of $L^2(m_0)$ the operator of $K_0$ has norm at most $\kappa_{\rm old}=(h_{\rm old}/h_0+e_0^2)/(1-e_0)$. Moreover $K_0=(\Jproj+\mathsf L)/z_0+R_{\rm old}$ with $\|R_{\rm old}\|\le19q/(Zh_0)$. \item \emph{Negative cap on the uniform law.} $K_0\succeq-r\bigl[1+(19/Z-1)r\bigr]h_0^{-1}I$ on $L^2(\nu_F)$. \item \emph{Blocks.} Let $\Blk$ be a block of primes $p\ge X\ge2^{24}$ with least prime $b$ and $\sum_{p\in\Blk}\log p\le L$, let $n_X\ge\lfloor L/\log X\rfloor$ be an integer (the certificate takes $n_X=\lfloor L/\log^-X\rfloor$ with a rational lower bound $\log^-X\le\log X$), $q_X=1/X$, $r_X\ge X^{-1/2}$ and $e_X=e_0(X)$, suppose $n_Xe_X<1$, and put $\bar H_X=(1-n_Xe_X)^{-1}$ and \[ k_{\rm D}(X,L)=\bar H_X\bigl[1+(e_o(X)-1)r_X\bigr], \] where $e_o(X)$ is the constant $e_o$ of \eqref{eq:signed-constants} at $(q_X,r_X)$. The notation $k_{\rm D}(X,L)$ suppresses the choices $n_X,r_X$ fixed here. If $[1+(e_o(X)-1)r_X]r_X<1$, then for every real function $\varphi$ on $H_{F,\Blk}=\prod_{p\in\Blk}H_{F,p}$ \[ \int\varphi(x)\varphi(y)\bigotimes_{p\in\Blk}K_{0,p}\, d\nu_{F,\Blk}(x)\,d\nu_{F,\Blk}(y)\ \ge\ -k_{\rm D}(X,L)\,b^{-1/2} \int\varphi^2\,d\nu_{F,\Blk} . \] Hence every two-layer fold component of the reference of $\Blk$ satisfies \[ \Pi_{F_j}\succeq_\iota-k_{\rm D}(X,L)\,b^{-1/2}\operatorname{Diag}_\iota(\Pi^{(1)}_{F_j}), \] which is the fold case of \cref{lem:front12:reference}(ii), with its reserved cap $k_{\rm D}=k_{\rm D}(X,L)$, on every block of a piece starting at $X$. \item \emph{Actual centred remainder.} Let $p\ge2^{24}$, let $T_{\rm old}$ be the operator of $K_0$ on $L^2(m_0)$, the Markov operator of \cref{lem:record:old-f-marginal}(c), let $O=T_{\rm old}-\Jproj$ be its centred part, and put \[ O_0=V_0PV^*_{2,m}-V_2PV^*_{0,m}=-\bigl(A_1V^*_{0,m}+V_0A_1^{*_m}\bigr), \] adjoints in $L^2(m_0)$. Then $O=O_0+R_o$ with $\|R_o\|\le e_oq$, where $e_o$ is the constant of \eqref{eq:signed-constants} at $(q,r)$; $O_0$ is self-adjoint, annihilates the constants, has its spectrum in $\{0\}\cup\{q/(1-q)\pm(q-q^3/(1-q)^2)^{1/2}\}$, and $\|O_0\|\le\Gamma_Ar$, with $\Gamma_A$ of \cref{lem:actual-features}(d). Hence $T_{\rm old}\succeq-\bigl[1+(e_o-1)r\bigr]r\,I$ on $L^2(m_0)$, and the centred norm of $T_{\rm old}$ is at most $(\Gamma_A+e_or)r$. \end{enumerate} \end{lemma} \begin{proof} (a) All counts use \cref{lem:paley-triple}(a). Fix $x$. The label $y_0$ is an in-neighbour of $x_2$ other than $x_0$, and other than $x_1$ if $e_{12}=1$: $\frac{p-1}2-1-e_{12}$ choices. Then $y_2$ is a common out-neighbour of $x_0$ and $y_0$ other than $x_2$, and other than $x_1$ if $x_0\to x_1$ and $y_0\to x_1$; if $e_{01}=1$, exactly $k_p-1$ admissible $y_0$ satisfy $y_0\to x_1$, namely the common in-neighbours of $x_1,x_2$ other than $x_0$. Finally $y_1$ is any of the $p-5$ remaining labels. This gives $N_0$. The ordered pairs of sources $x_0\ne y_0$ with two distinct common out-neighbours $x_2,y_2$ number $p(p-1)k_p(k_p-1)$, and each extends in $(p-4)(p-5)$ ways; dividing by $|H_F|$ gives the mean $\bar N_0=(p-3)(p-7)(p-4)(p-5)/(8(p-2))$. As $\Psi_0=4$ on its support, $\E_yK_0(x,y)=4N_0(x)/(|H_F|z_0)$, and averaging over $x$ gives $z_0=4\bar N_0/|H_F|$; so each half marginal has the density $N_0/\bar N_0=g_0$. As $e_{01}+e_{12}\in\{0,1,2\}$, $g_0$ takes the values $1+2/(p-4)$, $1-2/((p-3)(p-4))$ and $1-2(p-1)/((p-3)(p-4))$, the last being the farthest from one and the first the largest; $\varsigma$ exchanges $e_{01}$ and $e_{12}$. Multiplying out, $(1-3q)(1-4q)(1-5q)(1-7q)-(1-14q)(1-q)(1-2q)^2=53q^2-273q^3+364q^4$, positive because $273^2<4\cdot53\cdot364$, which gives the expansion of $z_0$; and $(1-q)(1-2q)^2-(1-3q)(1-4q)(1-5q)(1-7q)=q(14-123q+385q^2-420q^3)>0$ for $q\le1/19$ gives $z_0\le1$. On a block, $g_{0,p}\le1+2/(p-4)\le1+e_0(p)\le 1+e_0(X)$ for $p\ge X$; and $1+y\le e^y$ and $e^{ny}\le(1-ny)^{-1}$ for $0\le ny<1$. (b) (i) By the kernel identities of \cref{subsec:middle-records:notation}, $\mathsf L=-(A_1V_0^*+V_0A_1^*)$; it annihilates the constants because $A_1$ does and maps into mean-zero functions. On $H_0$, $A_1^*A_1=qI$ and $M:=V_0^*A_1=-(I+P)/(p-1)$ (\cref{lem:paley-triple}(e)), so \cref{lem:two-feature-spectrum}, with $a=b=-q/(1-q)$ and $c=q$, gives the nonzero eigenvalues of $\mathsf L$ as $q/(1-q)\pm\sqrt{q-q^3/(1-q)^2}$. The bounds follow from $(q-q^3/(1-q)^2)^{1/2}\le r$ and $\varrho r=q\sqrt{1+q}/(1-q)\ge q/(1-q)$. (ii) The kernel $\mathsf A\mathsf B$ depends on $(x_0,x_2)$ and $(y_0,y_2)$ and is a product of two single cross edges; for independent uniform labels it is a tensor product of two operators of norm $r$, and \cref{lem:record:projection} with the density $2/(1-q)$ of a directed edge on both sides gives the bound. (iii) Both factors of $\mathsf C_{\rm rem}$ are nonnegative, and $\mathsf C_{\rm rem}^\top=\mathsf C_{\rm rem}$. Fix $x$. Then $\E_y\mathsf A=\E_y\mathsf B=0$. The pair $(y_0,y_2)$ is a uniform directed edge, with density $(1+\chi(y_2-y_0)-\one_{y_0=y_2})/(1-q)$ relative to two independent labels; against $\mathsf A\mathsf B=\chi(y_2-x_0)\chi(x_2-y_0)$ the three terms contribute $0$, $q\chi(x_2-x_0)=q$ and $-q^2$ (\cref{lem:paley-triple}(b) and $x_0\to x_2$). Hence $\E_y\mathsf A\mathsf B=q$ and $\E_y(1+\mathsf A)(1+\mathsf B)=1+q$, while $\E_y\Psi_0(x,y)=4N_0(x)/|H_F|\ge(p-5)(p-7)^2/(p(p-1)(p-2))$ by (a). The row sum of $\mathsf C_{\rm rem}$ at $x$ is the difference, \[ \frac{p+1}p-\frac{(p-5)(p-7)^2}{p(p-1)(p-2)} =\frac{17p^2-120p+247}{p(p-1)(p-2)}=\frac{q(17-120q+247q^2)}Z , \] at most $17q$ because $17-120q+247q^2\le17(1-3q+2q^2)$ for $q\le69/213$; and $17/Z\le36$. The Schur test for a nonnegative symmetric kernel bounds the norm by the largest row sum. (c) $\Pi_\perp\Jproj\Pi_\perp=0$, so by (b) $\|\Pi_\perp K_0\Pi_\perp\|\le(\Gamma r+2q/Z+36q)/z_0\le h_{\rm old}/h_0$. The bound in $L^2(m_0)$ is \cref{lem:record:actual-correlation}(a) with $m_L=m_R=m_0$, $\eta=e_0\ge\eta_F$ and all functions; and $R_{\rm old}=(\mathsf A\mathsf B-\mathsf C_{\rm rem})/z_0$. (d) By (b) and $\Jproj\succeq0$, $\Psi_0\succeq-(r-q+2q/Z+17q/Z)I=-r[1+(19/Z-1)r]I$; divide by $z_0\ge h_0$. (e), (f): see the end of \cref{subsec:record:f_remainders}. The proof of (f) uses \cref{lem:actual-features} and \cref{lem:record:conditional-collision}(d), and that of (e) uses (f). \end{proof} The reference uses the cap $k_{\rm D}$ for its fold type (\cref{lem:front12:reference}(ii)). Its values $k_{\rm D}(X,585)$ at the $33$ piece starts, all below the recorded F21 block caps of \cref{lem:layer12-caps}, are those of \cref{cert:record:old-f-cap}; at $X=Q_3$ the block count is $n_X=34$, $\bar H_X<1.0000035$, $1+(e_o-1)r_X<1.0014832$ and $k_{\rm D}<1.0014866$. \begin{corollary}[Actual marginal and centred norm of the reference fold record] \label{lem:record:old-f-marginal} Let $p\ge19$. \begin{enumerate}[label=(\alph*)] \item The actual half marginal is $m_0=g_0\nu_F$, with $g_0$ and $\|g_0-1\|_\infty=\eta_F$ as in \cref{lem:old-f-law}(a). \item The joint law of the two $\iota$-halves of the fold record has the density $K_0=\Psi_0/z_0$ relative to $\nu_F\otimes\nu_F$, with $z_0=(p-3)(p-4)(p-5)(p-7)/(p(p-1)(p-2)^2)\ge1-14q$. \item The Markov operator $T_{\rm old}$ of this coupling on $L^2(m_0)$ is self-adjoint, $T_{\rm old}\one=\one$, and, provided $(2/Z+36)q<1$ and $\eta_F<1$, \[ \|T_{\rm old}-\Jproj\|\le\kappa_F(q,r):=\frac{\dfrac{\bar\Gamma r+(2/Z+36)q} {1-(2/Z+36)q}+\eta_F^2}{1-\eta_F},\qquad \bar\varrho=\frac{r(1+q)}{1-q},\quad\bar\Gamma=1+\bar\varrho +\frac{q(1+\bar\varrho)}{1-2q}. \] \item Let $X$ be a nonempty finite set of middle blocks, $j\in\{0,1,2\}$, and $\kappa_X$ the largest value of $\kappa_F(1/p,p^{-1/2})$ at the primes $p$ of the blocks of $X$. The Markov operator $T_X$ at $\iota$ of $\Pi_X=\bigotimes_{\Blk\in X}\Pi_{F_j,\Blk}$ on $L^2(m_X)$, $m_X=\bigotimes_\Blk m_{F_j,\Blk}$ the actual half marginal, satisfies $\|T_X-\Jproj\|\le\kappa_X$ and $T_X\preceq(1-\kappa_X)\Jproj+\kappa_XI$; hence, if $\kappa_X<1$, with $J_X$ the law with independent $\iota$-halves of law $m_X$, \[ Y[J_X]\ge\frac{Y[\Pi_X]-\kappa_X(1+o(1))C_XY}{1-\kappa_X}. \] \end{enumerate} \end{corollary} \begin{proof} (a) and (b) are \cref{lem:old-f-law}(a). (c) The layer swap preserves the record, so the coupling is symmetric, and $T_{\rm old}$ is self-adjoint and fixes the constants. As $\varrho\le\bar\varrho$, $\Gamma\le\bar\Gamma$, and \cref{lem:old-f-law}(b) gives $\|\Pi_\perp(\Psi_0-\Jproj)\Pi_\perp\|\le\bar\Gamma r+(2/Z+36)q$; with $z_0\ge1-14q\ge1-(2/Z+36)q$, $\|\Pi_\perp K_0\Pi_\perp\|$ is at most the inner fraction, and \cref{lem:record:actual-correlation}(a) with $\eta=\eta_F$ gives (c). (d) Every $\Pi_{F_j,\Blk}$ has the law $\bigotimes_{p\in\Blk}K_{0,p}$ at $\iota$ (\cref{lem:old-f-law}), so $T_X$ is the tensor product of the prime operators $T_{\rm old}$, each with $\|T_{\rm old}-\Jproj\|\le\kappa_X$; \cref{lem:sector}(c) gives $\|T_X-\Jproj\|\le\kappa_X$, and as $T_X$ is self-adjoint and fixes the constants, $T_X-\Jproj\preceq\kappa_X(I-\Jproj)$. The energy bound is (P3) of \cref{lem:energy-toolkit} at $\iota$ with the outside law $\mu$, followed by (E1) for the diagonal copy $\operatorname{Diag}_\iota(m_X)$. \end{proof} The certificate evaluates $\kappa_F$ at the piece start with $\bar\varrho=r(1+q)/(1-q)$, which exceeds the exact norm $\varrho=r\sqrt{1+q}/(1-q)$ of $V_0^*V_2$, and with $1-(2/Z+36)q$, which is below $z_0$; both substitutions only increase $\kappa_F$, which is admissible in $(q,r)$. The bound $\kappa_{\rm old}$ of \cref{lem:old-f-law}(c) bounds the same norm; the variance credits use $\kappa_F$, and the block bounds of the signed law the actual centred norm $(\Gamma_A+e_or)r$ of \cref{lem:old-f-law}(f). The actual half marginal $m_0$ is not uniform, but its pair laws are exact and simple, and they give the correlations of the feature spaces without any density-perturbation allowance. \begin{lemma}[Exact actual features]\label{lem:actual-features} Let $p\ge19$, $\mu=2/(p-4)$, and let $m_{ij}$ be the law of $(x_i,x_j)$ under the actual half marginal $m_0$ of \cref{lem:old-f-law}(a). \begin{enumerate}[label=(\alph*)] \item $m_{01}(a,b)=m_{12}(a,b)=\dfrac{1-\mu\chi(b-a)}{p(p-1)}$ for $a\ne b$, and $m_{02}$ is uniform on the pairs $a\to b$. \item On $H_0$, $V^*_{0,m}V_2=(P-qI)/(1-q)$ and $V^*_{0,m}V_1=V^*_{1,m}V_2=-(I+\mu pP)/(p-1)$. Hence the correlations of the singleton feature spaces in $L^2(m_0)$ are \[ \varrho_{02}=\|V^*_{0,m}V_2\|=\frac{r\sqrt{1+q}}{1-q},\qquad \varrho_{01}=\|V^*_{0,m}V_1\|=\|V^*_{1,m}V_2\| =\frac q{1-q}\Bigl(1+\frac{4q}{(1-4q)^2}\Bigr)^{1/2}; \] $\varrho_{02}$ is the number $\varrho$ of \cref{lem:paley-triple}(d). \item On $H_0$, \begin{gather*} A_3^{*_m}A_3=\frac{q(1-2q-q^2)}{1-q}\,I\preceq qI,\qquad A_3^{*_m}V_0=\frac{p+4}{p(p-1)(p-4)}\,I,\\ V^*_{1,m}A_3=-\frac q{p-1}I+\frac\mu{p-1}P,\qquad V^*_{2,m}A_3=-\frac q{p-1}I-\frac\mu{p-1}P . \end{gather*} Hence, as operators from $H_0$ to $L^2(m_0)$, $\|A_1\|=\|A_2\|=r$, $\|A_3^\circ\|\le\|A_3\|\le r$ and $\|\Pi_{\mathcal H_1+\mathcal H_2}A_3\|\le J_Fqr$, where \[ J_F=\Bigl(\frac2{1-\varrho_{01}}\Bigr)^{1/2} \Bigl(\frac r{1-q}+\frac{2q}{(1-q)(1-4q)}\Bigr). \] \item The synthesis map $(h_0,h_1,h_2,h_3)\mapsto V_0h_0+(A_2h_1+A_1h_2+A_3h_3)/r$ from $H_0^4$ to $L^2(m_0)$ has squared norm at most \[ \Gamma_A=1+\varrho_{02}+2\varrho_{01}+\frac{qr(1+4q)}{(1-q)(1-4q)} +\frac{2qr}{1-q}+\frac{4q^2}{(1-q)(1-4q)} . \] \item Let $\Blk$ be a middle block with least prime $b$ and actual marginal $m_{0,\Blk}=\bigotimes_pm_{0,p}$, and let $\mathcal H_i(\Blk)$ and $\mathcal K_{12}(\Blk)$ be the spaces of \cref{subsec:middle-records:notation} for the whole objects. Let $\mathcal V_0$ be the direct sum over $p\in\Blk$ of the maps $V_0$ at $p$, an isometry from $\bigoplus_pH_0(\mathbb F_p)$ into $\mathcal H_0(\Blk)$, and let $\mathcal A_1,\mathcal A_2,\mathcal A_3$ be the direct sums of the prime arms $A_2$, $A_1$, $A_3^\circ$. Then $\mathcal A_1$, $\mathcal A_2$, $\mathcal A_3$ have ranges in $\mathcal H_1(\Blk)$, $\mathcal H_2(\Blk)$, $\mathcal K_{12}(\Blk)$ and norms at most $b^{-1/2}$, and for real $c_1,c_2,c_3$ and $\mathcal A=c_1\mathcal A_1+c_2\mathcal A_2+c_3\mathcal A_3$ the star $\mathcal A\mathcal V_0^*-\mathcal V_0\mathcal A^*$ on $L^2(m_{0,\Blk})$ is the orthogonal sum over $p\in\Blk$ of the prime stars $(c_1A_2+c_2A_1+c_3A_3^\circ)V^*_{0,m}-V_0(c_1A_2+c_2A_1+c_3A_3^\circ)^{*_m}$ on the sectors of exact support $\{p\}$. \end{enumerate} \end{lemma} \begin{proof} (a) By \cref{lem:old-f-law}(a) the weight of a half $x$ under $m_0$ is proportional to $\one[x_0\to x_2](d-1-e_{01}-e_{12})$, with $d=(p-1)/2$; put $k=k_p=(d-1)/2$. Fix $(x_1,x_2)=(a,b)$ with $a\ne b$ and put $j=\one[a\to b]$. The label $x_0$ is an in-neighbour of $b$ other than $a$, in $d-j$ ways, and $k$ of these are also in-neighbours of $a$ (\cref{lem:paley-triple}(a)); so the total weight is $(d-j)(d-1-j)-k$, which is $(d-1)(d-\frac12)$ for $j=0$ and $(d-1)(d-\frac52)$ for $j=1$. Their mean over the two values of $j$ is $(d-1)(d-\frac32)=(d-1)(p-4)/2$, and the two values are this mean times $1+\mu$ and $1-\mu$; as $\chi(b-a)=2j-1$, this is the formula for $m_{12}$. The map $\varsigma$ preserves $m_0$ (\cref{lem:old-f-law}(a)) and sends $(x_0,x_1)$ to $(-x_2,-x_1)$, so $m_{01}(a,b)=m_{12}(-b,-a)$, which is the same formula. For $x_0\to x_2$, the sum of $d-1-e_{01}-e_{12}$ over $x_1\notin\{x_0,x_2\}$ is $(p-2)(d-1)-2(d-1)$, the same for every directed pair; so $m_{02}$ is uniform on the directed pairs. (b) The first identity is that of \cref{lem:paley-triple}(d), as $m_{02}$ is the uniform law of directed pairs, as under $\nu_F$. For $f\in H_0$, by (a), $(V^*_{0,m}V_1f)(a)=\sum_{b\ne a}\frac{1-\mu\chi(b-a)}{p-1}f(b) =-\frac{f(a)+\mu p(Pf)(a)}{p-1}$, and likewise for $V^*_{1,m}V_2$. On $H_0$ the operator $P$ is normal with eigenvalues $\pm ir$ (\cref{lem:paley-triple}(c)), so $\|P-qI\|^2=q+q^2$ and $\|I+\mu pP\|^2=1+\mu^2p$, and $\mu^2p=4q/(1-4q)^2$. (c) For $h\in H_0$, $A_3h$ is the function $-\frac1p\sum_s\chi(s-x_1)\chi(s-x_2)h(s)$ of $(x_1,x_2)$, which is symmetric in $(x_1,x_2)$; and the density of $m_{12}$ relative to the uniform law of distinct pairs is $1-\mu\chi(x_2-x_1)$, whose nonconstant part is antisymmetric. So the Gram $A_3^{*_m}A_3$ is that of the uniform law of distinct pairs. The pair $(x_1,x_2)$ under $\nu_F$ gives the same Gram, since its density relative to that law is $1-\chi(x_2-x_1)/(p-2)$, and it is the value $(1-2q-q^2)/(p-1)\cdot I$ of \cref{lem:paley-triple}(e). Next, by (a) and \eqref{eq:two-root}, \[ (V^*_{1,m}A_3h)(a)=-\frac1{p(p-1)}\sum_s\chi(s-a)h(s) \sum_{b\ne a}\bigl(1-\mu\chi(b-a)\bigr)\chi(s-b) =\frac{-h(a)+\mu p(Ph)(a)}{p(p-1)}, \] because the inner sum is $-\chi(s-a)-\mu$ for $s\ne a$; conditioning on $x_2$ instead, the inner sum is $-\chi(s-b)+\mu$, which gives $V^*_{2,m}A_3$. For $A_3^{*_m}V_0$, translation invariance shows that $\E_{m_0}[\chi(s-x_1)\chi(s-x_2)\mid x_0=a]=\kappa(s-a)$ for a function $\kappa$; the computation below gives $\kappa(0)=\kappa_0$ and $\kappa(t)=\kappa_1$ for every $t\ne0$, and then $A_3^{*_m}V_0=-q(\kappa_0-\kappa_1)I$ on $H_0$, since $\ip{A_3h}{V_0h'}_{m_0}=-\E_a\E_sh'(a)h(s)\kappa(s-a)$. Fix $x_0=0$ and write $b=x_1$, $c=x_2$; the conditional weight is $\one[0\to c](d-1-e_{0b}-e_{bc})$, of total $d(d-1)(p-4)$. With $e_{0b}=(1+\chi(b))/2$, $e_{bc}=(1+\chi(c-b))/2$ and \eqref{eq:two-root}, the sum over $b\notin\{0,c\}$ of $\chi(b)$ times the weight is $-(p-3)$ for every $c$, so $\kappa_0=-d(p-3)/(d(d-1)(p-4))=-2/(p-4)$. For $s\ne0$ put $\xi=\chi(s)$, $u=\chi(s-c)$ and $v=\chi(c)$; the sums over $b\notin\{0,c\}$ of $\chi(s-b)$, $\chi(b)\chi(s-b)$ and $\chi(c-b)\chi(s-b)$ are $-\xi-u$, $1-vu$ and $p\one_{c=s}-1-v\xi$, so the sum over $b$ of the weight times $\chi(s-b)$ is $\frac12[(v-(p-5))(\xi+u)-p\one_{c=s}]$. Summing $u$ times this over $c\ne0$ with the factor $\one[0\to c]=(1+v)/2$, and using $(1+v)(v-(p-5))=-(p-6)(1+v)$, $\sum_{c\ne0}(1+v)u=1-\xi$ and $\sum_{c\ne0}(1+v)u^2=p-2-\xi$, gives $-(p-6)(p-3)/4$, the term with $\one_{c=s}$ vanishing because $u=0$ at $c=s$; so $\kappa_1=-(p-6)/((p-1)(p-4))$ and $-q(\kappa_0-\kappa_1)=(p+4)/(p(p-1)(p-4))$. Finally $\|A_i\|=\|P|_{H_0}\|=r$ for $i=1,2$, as $V_1,V_2$ are isometries; $\|A_3\|^2\le q$ by the first identity. The Gram of $(V_1,V_2)$ on $H_0^2$ is at least $(1-\varrho_{01})I$ by (b), so $\|\Pi_{\mathcal H_1+\mathcal H_2}A_3\|\le(1-\varrho_{01})^{-1/2}\sqrt2\max_i \|V^*_{i,m}A_3\|$, and $\|V^*_{i,m}A_3\|\le q/(p-1)+\mu r/(p-1)= qr\bigl(r/(1-q)+2q/((1-q)(1-4q))\bigr)$. (d) The Gram of the four maps is a $4\times4$ block operator on $H_0^4$ with diagonal blocks of norm at most one (by (c), and as $V_0$, $A_2/r$, $A_1/r$ are isometries). Its off-diagonal blocks have the norms $\varrho_{01}$ (for $V_0$ and $A_2/r$, since $P/r$ is unitary on $H_0$), $\varrho_{02}$ ($V_0$ and $A_1/r$), $\varrho_{01}$ ($A_2/r$ and $A_1/r$), $\|A_3^{*_m}V_0\|/r=qr(1+4q)/((1-q)(1-4q))$ and $\|V^*_{i,m}A_3\|/r\le qr/(1-q)+2q^2/((1-q)(1-4q))$ for $i=1,2$, by (b) and (c). Every row sum of these norms is at most $\Gamma_A$, and the Schur test bounds the norm of the Gram by the largest row sum. (e) The Markov operators of couplings with exact marginals preserve the sectors of exact prime support (\cref{lem:sector}(a)), and the stars are defined sectorwise. A function of the prime-$p$ labels lying in $\mathcal H_i(p)$ lies in $\mathcal H_i(\Blk)$. One lying in $\mathcal K_{12}(p)$ lies in $\mathcal K_{12}(\Blk)$: the conditional expectation under $m_{0,\Blk}$ of a function of the whole-object label $x_1$ given the prime-$p$ labels is a function of $x_{1,p}$ alone, hence lies in $\mathcal H_1(p)$ plus the constants, which is orthogonal to $\mathcal K_{12}(p)$; likewise for $x_2$. The prime pieces of $\mathcal V_0$ and of each $\mathcal A_i$ have ranges in the mutually orthogonal sectors of exact support $\{p\}$, so these maps are isometric, respectively of norm $\max_p\|A\|\le\max_pr_p\le b^{-1/2}$ by (c), and the star splits into its prime stars. \end{proof} \subsection{Adding an edge together with its mirror: first-order change purely skew}\label{subsec:mirror} This subsection contains the algebraic idea on which the fold replacement rests. Recall that $x$ and $y$ are the layer-zero and layer-one triples of a fold record at one prime. For the record $F_1$ to accept the six queries, one further cross edge is needed beyond the two reference edges, namely $x_1\to y_0$ (\cref{cert:record:middle-geometry}); its channel is $\mathsf C$. Imposing only this edge would change the record already at first order in $r=p^{-1/2}$ in its symmetric part, which is too expensive. The reserved reflection sends the channel $\mathsf C$ to $-\mathsf D$, where $\mathsf D$ is the channel of the mirror edge $x_0\to y_1$. Imposing the mirror edge as well cancels the first-order symmetric change exactly, leaving a purely skew first-order change and a symmetric change only at second order. Part~(d) of the next lemma is the one-parameter signed form of this pairing used in \cref{subsec:oct24:pure-local}; mirror pairing itself is the case $\tlaw=0$. \begin{lemma}[Mirror pairing]\label{lem:mirror} Let $\Phi=(1+\mathsf A)(1+\mathsf B)\bigl[(1+\mathsf C)(1+\mathsf D)-1\bigr]$ and $\Phi'=(1+\mathsf A)(1+\mathsf B)\bigl[(1+\mathsf C)(1-\mathsf D)-1\bigr]$, polynomials in the channels \eqref{eq:middle:channels}, read as kernels. \begin{enumerate}[label=(\alph*)] \item $\operatorname{Sym}\Phi=\Phi_{\rm s}:=(1+\mathsf A)(1+\mathsf B)\mathsf C\mathsf D$ and $\operatorname{Skew}\Phi=\Phi_{\rm a}:=(1+\mathsf A)(1+\mathsf B)(\mathsf C+\mathsf D)$, whereas $\operatorname{Skew}\Phi'=0$ and $\operatorname{Sym}\Phi'=(1+\mathsf A)(1+\mathsf B)(\mathsf C-\mathsf D-\mathsf C\mathsf D)$. \item The four monomials $\mathsf C\mathsf D$, $\mathsf A\mathsf C\mathsf D$, $\mathsf B\mathsf C\mathsf D$, $\mathsf A\mathsf B\mathsf C\mathsf D$ of $\Phi_{\rm s}$ are nonstars: each contains the two-edge matching of $\mathsf C$ ($x_1$--$y_0$) and $\mathsf D$ ($x_0$--$y_1$), whose endpoints span only two of the four pairs of $\{x_0,x_1\}\times\{y_0,y_1\}$. The skew part splits as $\Phi_{\rm a}=L_p+\Phi_{\rm a,ns}$ into the star part $L_p=\mathsf C+\mathsf D+\mathsf A\mathsf D+\mathsf B\mathsf C$ and the nonstar part $\Phi_{\rm a,ns}=\mathsf A\mathsf C+\mathsf B\mathsf D+\mathsf A\mathsf B\mathsf C +\mathsf A\mathsf B\mathsf D$. \item $L_p=A_\star V_0^*-V_0A_\star^*$ on $L^2(\nu_F)$, with $A_\star=A_2+A_3$; it annihilates the constants, has mean-zero range, and \[ \|L_p\|=|\beta|r+(\gamma-\lambda^2)^{1/2}\le l:=r\Bigl[\Bigl(\frac{2+2q^2/(1-2q)} {1-q}\Bigr)^{1/2}+\frac q{1-q}\Bigr], \] where $\lambda=\frac{p+2}{p(p-1)(p-2)}$, $\beta=-\frac1{p-1}$ and $\gamma=q+\frac{1-2q-q^2}{p-1}+\frac{2q}{(p-1)(p-2)}$. In particular $l/r\to\sqrt2$ as $q\to0$, and $l/r$ is admissible in $(q,r)$. \item \emph{The signed pairing.} For $0\le\tlaw\le1$ let \[ \Phi_\tlaw=(1+\mathsf C)\bigl(1+(1-\tlaw)\mathsf B\bigr) \bigl[1+\mathsf D+(1+\tlaw)\mathsf A+(1-\tlaw)\mathsf A\mathsf D\bigr] -(1+\mathsf A)(1+\mathsf B), \] and put $\tilde x_\tlaw=\mathsf D+\tlaw\mathsf A+(1-\tlaw)\mathsf A\mathsf D$ and $\tilde y_\tlaw=\mathsf C-\tlaw\mathsf B+(1-\tlaw)\mathsf B\mathsf C$. Then $\Phi_0=\Phi$, \[ \operatorname{Sym}\Phi_\tlaw=\tilde x_\tlaw\tilde y_\tlaw,\qquad \operatorname{Skew}\Phi_\tlaw=L_{\tlaw,p}+K_\tlaw-K_\tlaw^\top,\qquad K_\tlaw=\mathsf A\mathsf C\bigl(1+(1-\tlaw)\mathsf B\bigr), \] where $L_{\tlaw,p}=\tilde x_\tlaw+\tilde y_\tlaw=\mathsf C+\mathsf D+\tlaw(\mathsf A-\mathsf B) +(1-\tlaw)(\mathsf A\mathsf D+\mathsf B\mathsf C)$ is, on $L^2(\nu_F)$, the operator $A_\tlaw V_0^*-V_0A_\tlaw^*$, with $A_\tlaw=A_2+\tlaw A_1+(1-\tlaw)A_3$ of \cref{subsec:middle-records:notation}. The factor $\tilde x_\tlaw$ is a rectangular star with centre $x_0$, leaves $y_1,y_2$ and coefficients $(1,\tlaw,1-\tlaw)$, and $\tilde y_\tlaw$ one with centre $y_0$, leaves $x_1,x_2$ and coefficients $-(1,\tlaw,1-\tlaw)$ (\cref{lem:record:projected-nonstar}(b)); $K_\tlaw$ does not depend on $y_1$, and its only factor that depends on $x_1$ is $\mathsf C$. \end{enumerate} \end{lemma} \begin{proof} (a) By \eqref{eq:middle:transpose}, $(1+\mathsf A)(1+\mathsf B)$ and $\mathsf C\mathsf D\mapsto(-\mathsf D)(-\mathsf C)$ are symmetric, $\mathsf C+\mathsf D$ is skew and $\mathsf C-\mathsf D$ is symmetric; and $(1+\mathsf C)(1\pm\mathsf D)-1=\mathsf C\pm\mathsf D\pm\mathsf C\mathsf D$. (b) is the expansion of the products; the star monomials of $\Phi_{\rm a}$ are the singletons $\mathsf C,\mathsf D$ and the products $\mathsf A\mathsf D$ (at $x_0$) and $\mathsf B\mathsf C$ (at $y_0$). (c) The kernels of $A_2V_0^*$ and $A_3V_0^*$ are $\mathsf C$ and $\mathsf B\mathsf C-q$ (\cref{subsec:middle-records:notation}); by \eqref{eq:middle:transpose} the kernel of the adjoint $V_0A_\star^*$ is $(\mathsf C+\mathsf B\mathsf C-q)^\top=-\mathsf D-\mathsf A\mathsf D-q$, and the difference is $L_p$. Each $A_j$ annihilates the constants and maps into mean-zero functions (\cref{lem:paley-triple}(e)), hence so does $L_p$. On $H_0$, by \cref{lem:paley-triple}(e), $M:=V_0^*A_\star=\lambda I+\beta P$ and $A_\star^*A_\star=\gamma I$, because the parts of $A_2^*A_3$ and $A_3^*A_2$ that contain $P$ cancel ($P^*=-P$). Apply \cref{lem:two-feature-spectrum} with $(a,b,c)=(\lambda,\beta,\gamma)$ to obtain the stated norm. Finally $|\beta|r=rq/(1-q)$ and $\gamma/q=\frac{2-3q-q^2}{1-q}+\frac{2q^2}{(1-q)(1-2q)}\le\frac{2+2q^2/(1-2q)}{1-q}$. (d) The first factor of $\Phi_\tlaw+(1+\mathsf A)(1+\mathsf B)$ is $(1+\mathsf C)(1+(1-\tlaw)\mathsf B)=1+\mathsf B+\tilde y_\tlaw$ times $1+\mathsf D+(1+\tlaw)\mathsf A+(1-\tlaw)\mathsf A\mathsf D=1+\mathsf A+\tilde x_\tlaw$. The two factors are polynomials in disjoint channels, so \[ \Phi_\tlaw=(1+\mathsf B)\tilde x_\tlaw+(1+\mathsf A)\tilde y_\tlaw +\tilde x_\tlaw\tilde y_\tlaw . \] By \eqref{eq:middle:transpose}, $\tilde x_\tlaw^\top=-\mathsf C+\tlaw\mathsf B -(1-\tlaw)\mathsf B\mathsf C=-\tilde y_\tlaw$ and $\tilde y_\tlaw^\top=-\tilde x_\tlaw$, so $\Phi_\tlaw^\top=-(1+\mathsf A)\tilde y_\tlaw-(1+\mathsf B)\tilde x_\tlaw +\tilde x_\tlaw\tilde y_\tlaw$. Hence $\operatorname{Sym}\Phi_\tlaw=\tilde x_\tlaw\tilde y_\tlaw$ and $\operatorname{Skew}\Phi_\tlaw=(\tilde x_\tlaw+\tilde y_\tlaw)+(\mathsf B\tilde x_\tlaw +\mathsf A\tilde y_\tlaw)$, and $\mathsf B\tilde x_\tlaw+\mathsf A\tilde y_\tlaw=\mathsf A\mathsf C(1+(1-\tlaw)\mathsf B) +\mathsf B\mathsf D(1+(1-\tlaw)\mathsf A)=K_\tlaw-K_\tlaw^\top$, since $K_\tlaw^\top=\mathsf B(-\mathsf D)(1+(1-\tlaw)\mathsf A)$. At $\tlaw=0$ the first factor is $(1+\mathsf C)(1+\mathsf B)(1+\mathsf A)(1+\mathsf D)$, so $\Phi_0=\Phi$. The kernels of $A_2V_0^*$, $A_1V_0^*$ and $A_3V_0^*$ are $\mathsf C$, $-\mathsf B$ and $\mathsf B\mathsf C-q$, so the kernel of $A_\tlaw V_0^*$ is $\tilde y_\tlaw-(1-\tlaw)q$ and that of its adjoint $V_0A_\tlaw^*$ is $-\tilde x_\tlaw-(1-\tlaw)q$; their difference is $L_{\tlaw,p}$. With $\mathsf D=\chi(y_1-x_0)$, $\mathsf A=\chi(y_2-x_0)$, $\mathsf C=-\chi(x_1-y_0)$ and $\mathsf B=\chi(x_2-y_0)$, $\tilde x_\tlaw$ and $\tilde y_\tlaw$ are the stated rectangular stars, and $K_\tlaw=\chi(y_2-x_0)\cdot\mathsf C(1+(1-\tlaw)\mathsf B)$ involves the labels $x_0,x_1,x_2,y_0,y_2$ only. \end{proof} \begin{remark}[Why the mirror]\label{rem:mirror-why} For the orientation $(1+\mathsf C)(1-\mathsf D)$ the whole first-order change $\mathsf C-\mathsf D$ is symmetric, priced in $S$, which enters the closing through $e^S$. For the pairing of \cref{lem:mirror} the symmetric change is of order $q$, and the first-order change is the skew two-arm star $L_p$ of norm about $\sqrt2\,r$: odd skew terms vanish in the expansion of the reserved cost, and the even products of such stars are priced by positive envelopes (\cref{thm:envelopes}), after reflection averaging, at a fraction of their norms. The signed record keeps this structure and lowers the leading norm from $\sqrt2\,r$ to about $|\mathbf a_\tlaw|r=(1+\tlaw^2+(1-\tlaw)^2)^{1/2}r$ by two further product laws with coefficients $\pm\tlaw/2$ (\cref{lem:mirror}(d)). The cost is a total variation $1+\tlaw$ per block, which enters only the vanishing remainders of the comparison theorem through the variation factor of \cref{def:cp4}, and a larger second-order symmetric part ($s_F$ of \cref{prop:signed-bounds}). Replacements that change the cross edge $y_0\to x_2$ of the reference record, and the limits of positive mixtures, are discussed in \cref{subsec:obs:pairing}. \end{remark} \subsection{The signed combination over a whole block replacing \texorpdfstring{$F_1,F_2$}{F\_1,F\_2}}\label{subsec:oct24:pure-local} The comparison records of $F_1$ and $F_2$ replace the reference fold record, at every prime, by three positive accepting kernels repaired to the actual half marginal $m_0$, and combine their tensor products over the block with the signed coefficients $1,\tlaw/2,-\tlaw/2$. The repair precedes tensorization and the signed sum follows it: every product has exactly the product of the actual prime marginals, and the sector lemma prices the block difference by its prime differences (\cref{lem:sector}(b) with its closing clause and (h), \cref{rem:signed-mixture-sectors}). In this subsection the densities of the components are taken relative to $m_0\otimes m_0$; the operator of such a density $P$ on $L^2(m_0)$ is its Markov operator $T[P]\psi(x)=\int P(x,y)\psi(y)\,dm_0(y)$, which is the operator on $L^2(m_0)$, in the sense of \cref{subsec:middle-records:notation}, of the $\nu_F\otimes\nu_F$-density $P\,(g_0\otimes g_0)$. \begin{lemma}[Positive components with the actual half marginal] \label{lem:signed-components} Let $p\ge2^{24}$, $0\le\tlaw\le1$ and $(u,v)\in\{(1,1),(-1,1),(-1,-1)\}$, and on $H_F\times H_F$ put \[ U_{uv}=2\,\one[x_1\to y_0]\bigl(1+(1-\tlaw)\mathsf B\bigr)(1+u\mathsf D)(1+v\mathsf A), \qquad z_{uv}=\E_{\nu_F\otimes\nu_F}U_{uv},\qquad R_{uv}=\frac{U_{uv}}{z_{uv}\,g_0\otimes g_0}, \] so that $R_{uv}$ is the density of the probability measure $U_{uv}\,\nu_F\otimes\nu_F/z_{uv}$ relative to $m_0\otimes m_0$. \begin{enumerate}[label=(\alph*)] \item $U_{uv}\ge0$; it vanishes unless $x_1\to y_0$, and it is invariant under $\mathcal G_p$ acting diagonally on all six labels. \item For all $x,y\in H_F$, $|\E_{y'\sim\nu_F}U_{uv}(x,y')-1|\le qR_{\rm row}$ and $|\E_{x'\sim\nu_F}U_{uv}(x',y)-1|\le qR_{\rm col}$, where \begin{gather*} R_{\rm row}=(5-3\tlaw)+\frac{2[1+(5-3\tlaw)q]}{1-2q} +(2-\tlaw)\Bigl(1+\frac{2q}{1-q}\Bigr),\\ R_{\rm col}=(5-4\tlaw)+\frac{2[1+(5-4\tlaw)q]}{1-2q}+\frac{1+q}{1-2q}; \end{gather*} both are below $10$, and $|z_{uv}-1|\le\eta_c:=10q$. \item The marginal defects $\alpha=\one-R_{uv}\one$ and $\beta=\one-R_{uv}^*\one$, $R_{uv}$ acting on $L^2(m_0)$, are $\mathcal G_p$-invariant and $m_0$-centred, and $|\alpha|,|\beta|\le M_c:=\frac{2\eta_c+(1+\eta_c)e_0}{h_c(1-e_0)}$, $h_c=1-\eta_c$. The query coupling $J_C=\frac2{1-q}\one[x_1\to y_0]$, a density relative to $m_0\otimes m_0$, has both marginals $m_0$, satisfies $J_C\beta=0$ and $J_C^*\alpha=0$, and $\|\Pi_\perp J_C\Pi_\perp\|\le\varrho_{02}$ on $L^2(m_0)$, with $\Pi_\perp$ the projection off the constants and $\varrho_{02}$ of \cref{lem:actual-features}(b). \item The density \[ P_{uv}=\frac{R_{uv}+J_C\bigl(\alpha(x)+\beta(y)\bigr)+2M_cJ_C}{1+2M_c} \] relative to $m_0\otimes m_0$ is that of a $\mathcal G_p$-invariant probability measure supported on $x_1\to y_0$, with both half marginals $m_0$, and $\|\Pi_\perp(T[P_{uv}]-T[R_{uv}])\Pi_\perp\|\le2M_c\bigl(\|\Pi_\perp T[R_{uv}]\Pi_\perp\| +2\varrho_{02}\bigr)$. \end{enumerate} \end{lemma} \begin{proof} (a) For $a\ne b$, $1+\chi(b-a)$ is $2$ if $a\to b$ and $0$ otherwise; the other three factors lie in $[0,2]$ for all values $0,\pm1$ of the channels; and the channels are invariant under the maps $t\mapsto\alpha t+\beta$ with $\alpha$ a nonzero square, acting on all labels. (b) \emph{Rows.} Fix $x$, and write $2\,\one[x_1\to y_0]=1+\mathsf C-\delta_{10}$, $\delta_{10}=\one[y_0=x_1]$ (at $y_0=x_1$ the channel $\mathsf C$ vanishes). Then $U_{uv}=H(1+u\mathsf D)(1+v\mathsf A)-\delta_{10}\bigl(1+(1-\tlaw)\mathsf B\bigr) (1+u\mathsf D)(1+v\mathsf A)$, where $H=(1+\mathsf C)(1+(1-\tlaw)\mathsf B)\ge0$ is a function of $y_0$. Under $\nu_F$ the label $y_0$ is uniform, $y_2$ is a uniform out-neighbour of $y_0$, and $y_1$ is uniform on the other $p-2$ labels. By \cref{lem:paley-triple}(b), $\E H=1+(1-\tlaw)\E_c\chi(c-x_1)\chi(x_2-c)= 1+(1-\tlaw)q$. Next $\E[\mathsf A\mid y_0=c]=(p\one_{c=x_0}-1-\chi(c-x_0))/(p-1)$, so $(p-1)\E[H\mathsf A]=H(x_0)-\E H-\E_c[H(c)\chi(c-x_0)]$. Here $H(x_0)$ is $0$ or $2(2-\tlaw)$, as $\chi(x_2-x_0)=1$, and $\E_c[H(c)\chi(c-x_0)]=-q+(1-\tlaw)q-(1-\tlaw)\E_c\chi((c-x_0)(c-x_1)(c-x_2))$, where the last average has modulus at most $2r$ by \cref{thm:weil}(a). Hence $|\E[H\mathsf A]|\le q(3-2\tlaw+q+2r)/(1-q)\le2(2-\tlaw)q$, the last step because $q+2r+(4-2\tlaw)q\le1$; so $|\E[H(1+v\mathsf A)]-1|\le(5-3\tlaw)q$. Given $(y_0,y_2)$, $|\E[\mathsf D\mid y_0,y_2]|=|\chi(y_0-x_0)+\chi(y_2-x_0)|/(p-2)\le 2q/(1-2q)$, and $H(1+v\mathsf A)\ge0$, so the term with $u\mathsf D$ is at most $\frac{2q}{1-2q}[1+(5-3\tlaw)q]$ in modulus. For the excluded query coincidence $y_0=x_1$ (the removed query of the preceding remark), at $y_0=x_1$ the factor $1+(1-\tlaw)\mathsf B$ is at most $2-\tlaw$, and with $\xi=\chi(x_1-x_0)$ the conditional means given $y_0=x_1$ are $\E\mathsf A=-(1+\xi)/(p-1)$, $\E\mathsf D=-\xi/(p-2)+(1+\xi)/((p-1)(p-2))$ and $\E\mathsf A\mathsf D=-(p-3)/((p-1)(p-2))$; the largest value of $1+u\E\mathsf D+v\E\mathsf A+uv\E\mathsf A\mathsf D$ over $u,v,\xi$ is $1+2/(p-1)$. These three bounds add up to $qR_{\rm row}$. \emph{Columns.} Fix $y$, and integrate $x_1$ first: given $(x_0,x_2)$ it is uniform on the other $p-2$ labels, so $|\E[\mathsf C\mid x_0,x_2]|=|\chi(y_0-x_0)+\chi(y_0-x_2)|/(p-2)\le2q/(1-2q)$. The remaining factor $(1+(1-\tlaw)\mathsf B)G$, $G=(1+u\mathsf D)(1+v\mathsf A)$ a function of $x_0$, is nonnegative; $\E G=1-uvq$ by \cref{lem:paley-triple}(b), and $\E[\mathsf B\mid x_0]=(p\one_{x_0=y_0}-1-\chi(x_0-y_0))/(p-1)$ is $1$ at $x_0=y_0$ and $0$ or $-2/(p-1)$ elsewhere, so $-2q(1+q)/(1-q)\le\E[\mathsf BG]\le4q$. Hence $|\E[(1+(1-\tlaw)\mathsf B)G]-1|\le(5-4\tlaw)q$, and the $\mathsf C$-term is at most $\frac{2q}{1-2q}[1+(5-4\tlaw)q]$. The removed query has column mass $q\,\E[(1+(1-\tlaw)\chi(x_2-y_0))G(x_0)\mid x_1=y_0]\le q(1+q)/(1-2q)$: given $x_1=c$ the pair $(x_0,x_2)$ is uniform on the $(p-1)(p-2)/2$ directed pairs avoiding $c$, the sum over $x_2$ of $1+(1-\tlaw)\chi(x_2-c)$ is at most $(p-1)/2$ for every $x_0$, and $\sum_{x_0}G(x_0)=p(1-uvq)$. For $q\le1/100$ the two bounds are at most $9.19$ and $8.18$. Averaging the row estimate over $x$ gives $|z_{uv}-1|\le qR_{\rm row}<10q$. (c) $R_{uv}\one(x)=\E_{y\sim\nu_F}U_{uv}(x,y)/(z_{uv}g_0(x))$. By (b) the ratio $\E_yU_{uv}(x,y)/z_{uv}$ is within $2\eta_c/h_c$ of one, and $|g_0-1|\le e_0$ (\cref{lem:old-f-law}(a)), so $|\alpha|\le(e_0+2\eta_c/h_c)/(1-e_0)\le M_c$; likewise for $\beta$. Invariance holds because $U_{uv}$, $\nu_F$ and $g_0$ are invariant, and $\int\alpha\,dm_0=1-\iint R_{uv}\,dm_0\,dm_0=0$. The label $y_0$ is uniform under $m_0$ and, for every $x$, $\Pr(x_1\to y_0)=(1-q)/2$; so $J_C\one=\one$, and likewise $J_C^*\one=\one$. As $\beta$ is translation invariant and $m_0$-centred, $\E_{m_0}[\beta\mid y_0]=0$ (\cref{lem:spec:affpair}(d)(iii)), and $(J_C\beta)(x)=\frac2{1-q}\E_{m_0}\bigl[\one[x_1\to y_0]\E[\beta\mid y_0]\bigr]=0$; likewise $J_C^*\alpha=0$. Finally, as $2\,\one[a\to c]=1+\chi(c-a)-\one_{c=a}$, the operator of $J_C$ on $L^2(m_0)$ is $V_1SV^*_{0,m}$ with $S=(\Jproj+P-qI)/(1-q)$ on $L^2(\Fp)$; so $\Pi_\perp J_C\Pi_\perp=V_1\frac{P-qI}{1-q}V^*_{0,m}\Pi_\perp$, of norm at most $\|P-qI\|/(1-q)=\varrho_{02}$ on $H_0$. (d) This is \cref{cor:markov-completion} with $m_X=m_Y=m_0$, $R=R_{uv}$, $J=J_C$ and $M=M_c$; the density vanishes off $x_1\to y_0$, where both $R_{uv}$ and $J_C$ vanish, and it is invariant because $R_{uv}$, $J_C$, $\alpha$ and $\beta$ are. \end{proof} \begin{remark}[Coincidences of the two halves] The kernels $U_{uv}$ are defined at every pair of halves; only the query coincidence $y_0=x_1$ is excluded. At another coincidence $x_i=y_j$ the channels of that pair vanish, and $U_{uv}\ge0$ there. Acceptance needs only $x_1\to y_0$ (\cref{cert:record:middle-geometry}); invariance under $\mathcal G_p$, hence uniform one-slot marginals and uniform queried pairs, holds on the whole product; and every bound of \cref{prop:signed-bounds} is a bound for the operator of the kernel on all pairs of halves (stars and nonstars for independent labels, compressed by the induced densities; the removed query charged $k_{\rm col}q$). No later statement assumes distinct labels in the two halves of a fold record: the middle frame (\cref{def:record:frame}) and the dominating matrices of \cref{sec:envelopes}, the matching Gram and the mean credit use operators on $L^2(m_0)$; the restorations use only the reference records and the root; admissibility (O1) allows invariant signed measures and (O2) applies only the records' own norms at $\iota$ (\cref{def:admissible}); and \ref{it:record:R4} concerns only tail primes. \end{remark} \begin{definition}[The signed whole-block fold record]\label{def:record:mixture} Let $p\ge2^{24}$ and $0\le\tlaw\le1$; the construction uses $\tlaw=127/500$. \begin{enumerate}[label=(\alph*)] \item \emph{Reference law:} $\Psi_0$, $z_0$, $K_0=\Psi_0/z_0$ and $m_0=g_0\nu_F$ of \cref{lem:old-f-law}. \item \emph{Components:} the densities $P_{++,p}$, $P_{-+,p}$, $P_{--,p}$ of \cref{lem:signed-components} at every prime $p$, relative to $m_{0,p}\otimes m_{0,p}$. \item \emph{The record of $F_1$} on a middle block $\Blk$ is the signed measure with the density \begin{equation}\label{eq:signed-law} K_{\tlaw,\Blk}=\bigotimes_{p\in\Blk}P_{++,p} +\frac\tlaw2\bigotimes_{p\in\Blk}P_{-+,p}-\frac\tlaw2\bigotimes_{p\in\Blk}P_{--,p} \end{equation} relative to $m_{0,\Blk}\otimes m_{0,\Blk}$, $m_{0,\Blk}=\bigotimes_pm_{0,p}$: the signed sum is taken after the three products. It has mass one, both half marginals $m_{0,\Blk}$, and total variation at most $1+\tlaw$, whatever the number of primes. \item \emph{The record of $F_2$} is the reflected transpose $K^\varsigma_{\tlaw,\Blk}$, taken componentwise at every prime; its reference law is $K_0^\varsigma=K_0$. \item Both are placed by $F_1$ and $F_2$ (\cref{lem:record:fold-identification}(b)), with the weight $w_{\rm D}r$ of the records they replace. At $\tlaw=0$ the record is $\bigotimes_pP_{++,p}$, whose raw kernel $U_{++}$ adds to the reference record the query edge and its mirror: it is a mirror pairing in the sense of \cref{lem:mirror}. \end{enumerate} \end{definition} For one prime put $K_{\tlaw,p}=P_{++,p}+\frac\tlaw2P_{-+,p}-\frac\tlaw2P_{--,p}$, the same combination as \eqref{eq:signed-law} at one prime, and write $D_{\tlaw,p}=T[K_{\tlaw,p}]-T_{\rm old}$ for the record difference of $F_1$ at $p$, where $T$ is extended linearly to signed densities and $T_{\rm old}$ is the operator of $K_0$ on $L^2(m_0)$, that is $T$ of the $m_0\otimes m_0$-density $K_0/(g_0\otimes g_0)$; the difference $D_{\tlaw,p}$ annihilates the constants on both sides, and $D^{\rm s}_{\tlaw,p}$, $D^{\rm a}_{\tlaw,p}$ are its symmetric and skew parts. The leading part of $D^{\rm a}_{\tlaw,p}$ is \begin{equation}\label{eq:signed-leading} L^\circ_{\tlaw,p}=A^\circ_\tlaw V_{0,m}^*-V_0(A^\circ_\tlaw)^{*_m},\qquad A^\circ_\tlaw=A_2+\tlaw A_1+(1-\tlaw)A_3^\circ, \end{equation} on $L^2(m_0)$, adjoints taken in $L^2(m_0)$: the operator $L_{\tlaw,p}$ of \cref{lem:mirror}(d) with the adjoints of the actual marginal and with $A_3$ replaced by its part orthogonal to the singleton features. It is a three-arm star with centre $\mathcal H_0$, arms in $\mathcal H_1$, $\mathcal H_2$ and $\mathcal K_{12}$, and coefficients $(1,\tlaw,1-\tlaw)$; at $\tlaw=0$ it is the two-arm star $A^\circ_\star V^*_{0,m}-V_0(A^\circ_\star)^{*_m}$ of the mirror pairing. For $F_2$ the record difference is $\mathcal UD_{\tlaw,p}^*\mathcal U$, since $K^\varsigma=\mathcal UK^\top\mathcal U$ componentwise and $\mathcal UK_0\mathcal U=K_0$; $\mathcal U$ is unitary on $L^2(m_0)$ because $g_0\circ\varsigma=g_0$, and the symmetric and skew parts of $\mathcal UD_{\tlaw,p}^*\mathcal U$ are $\mathcal UD^{\rm s}_{\tlaw,p}\mathcal U$ and $-\mathcal UD^{\rm a}_{\tlaw,p}\mathcal U$. \paragraph{Acceptance.} By \cref{cert:record:middle-geometry}, the six queries need in the two-layer $F_1$ exactly the cross edge $x_1\to y_0$ and in $F_2$ exactly $x_2\to y_1$; $F_0$ accepts. Every component $P_{uv,p}$ is supported on $x_1\to y_0$ (\cref{lem:signed-components}(a),(d)), so every product of components accepts the query of $F_1$ at every prime of the block; as $\mathsf C^\varsigma=\chi(y_1-x_2)$, the reflected components accept the query of $F_2$. Every component is $\mathcal G_p$-invariant, so its one-slot marginals are uniform and, $\mathcal G_p$ being transitive on the ordered pairs $(a,a')$ with $a\to a'$, its queried pair is uniform on the strict-square pairs. \begin{certificate}[Query images of the middle records]\label{cert:record:middle-geometry} The frozen geometry record \path{research/frontier_2026_10_17/structural/middle6_geometry.json}, with the labels $x_i=i$ and $y_i=3+i$, gives the following projections of the six slot queries of $\mathcal E_6$ onto each record (the queries as they read on the original labels, before any compression). In the two-layer records $F_0$ accepts, and the only needed cross edges are $x_1\to y_0$ in $F_1$, $x_2\to y_1$ in $F_2$ and $x_0\to y_1$ in $E_0$ and in $E_1$. In the one-layer records $E_0,E_1$ the only needed edge is $0\to1$; at the chamber cut $\vartheta_1$ for $E_0$ and $\vartheta_2$ for $E_1$, label $2$ lies on both sides of the cut and labels $0$ and $1$ on one side each. The two checker programs re-derived these facts independently (\path{research/record_gate_2026_10_18/U01/compute/geometry_components.py}, \path{research/record_gate_2026_10_18/U03/compute/indep_geometry.py}). \end{certificate} \subsection{Nonstar and coincidence remainders}\label{subsec:record:f_remainders} This subsection collects the nonstar, rectangular-star and coincidence bounds used by the signed fold records (\cref{prop:signed-bounds}) and by the reference fold record (\cref{lem:old-f-law}(e),(f)). No estimate of this subsection is applied to the matching records. A polynomial of degree at most one in each character attains its maximum modulus on $[-1,1]^4$ at a vertex, so it is bounded by its maximum on $\{\pm1\}^4$ everywhere, including where a character vanishes. \begin{lemma}[Projected nonstars and rectangular stars]\label{lem:record:projected-nonstar} \begin{enumerate}[label=(\alph*)] \item For each nonstar monomial $m$, $\|m\|\le\pi_mq$, where \[ \begin{gathered} \pi_{\mathsf A\mathsf B}=\frac2{1-q},\qquad \pi_{\mathsf A\mathsf C}=\pi_{\mathsf B\mathsf D}=\Bigl(\frac2Z\Bigr)^{1/2},\qquad \pi_{\mathsf C\mathsf D}=\frac1{1-2q},\\ \pi_{\mathsf A\mathsf B\mathsf C}=\pi_{\mathsf A\mathsf B\mathsf D}=\frac2{Z^{1/2}},\qquad \pi_{\mathsf A\mathsf C\mathsf D}=\pi_{\mathsf B\mathsf C\mathsf D}=\frac{\sqrt2}{1-2q},\qquad \pi_{\mathsf A\mathsf B\mathsf C\mathsf D}=\frac2{1-2q}. \end{gathered} \] Every $\pi_m$ is at most $2/Z$. Consequently $\|\Phi_{\rm s}\|\le\mathcal N_{\rm s}:=q(3+2\sqrt2)/(1-2q)$ and $\|\Phi_{\rm a,ns}\|\le\mathcal N_{\rm a}:=q\bigl(2(2/Z)^{1/2}+4/Z^{1/2}\bigr)$. \item \emph{Rectangular stars.} For independent uniform labels $z,u,v$ and real $a_1,a_2,a_3$, the \emph{rectangular star} $a_1\chi(u-z)+a_2\chi(v-z)+a_3\chi(u-z)\chi(v-z)$, as an operator between functions of $z$ and functions of $(u,v)$, has norm at most $r(a_1^2+a_2^2+a_3^2)^{1/2}$: its Gram on mean-zero functions of $z$ is $q(a_1^2+a_2^2+a_3^2-2qa_3^2)$, and on the constants $a_3^2q(1-q)$. A product of two rectangular stars on disjoint sets of labels has norm at most the product of their norms, and its restriction to $H_F\times H_F$, as a kernel relative to $\nu_F\otimes\nu_F$, has norm at most $2/Z$ times that. \end{enumerate} \end{lemma} \begin{proof} (a) A nonstar monomial is $m=m_1m_2$, with $m_1$ a nonempty product of characters of the star at $x_0$ and $m_2$ of the star at $y_0$. For independent uniform labels the operator of $m$ is the tensor product of those of $m_1$ and $m_2$. A single edge has norm $r$, and a full star has norm $(q-q^2)^{1/2}$, its Gram operator being $q(1-2q)I+q^2\Jproj$ by \cref{lem:paley-triple}(b); so monomials with two, three and four edges have norms $q$, $q(1-q)^{1/2}$ and $q(1-q)$. Each $m$ depends on $x$ through the coordinates $I$ and on $y$ through $J$, where $(I,J)$ is $(\{0,2\},\{0,2\})$, $(\{0,1\},\{0,2\})$, $(\{0,2\},\{0,1\})$, $(\{0,1\},\{0,1\})$, $(\{0,1,2\},\{0,2\})$, $(\{0,2\},\{0,1,2\})$, $(\{0,1\},\{0,1,2\})$, $(\{0,1,2\},\{0,1\})$ and $(\{0,1,2\},\{0,1,2\})$ in the order of the display; \cref{lem:record:projection} multiplies the norms by the square roots of the two density bounds, which gives the $\pi_m$. The coefficients of $\Phi_{\rm s}$ are one on $\mathsf C\mathsf D,\mathsf A\mathsf C\mathsf D, \mathsf B\mathsf C\mathsf D,\mathsf A\mathsf B\mathsf C\mathsf D$, and those of $\Phi_{\rm a,ns}$ one on $\mathsf A\mathsf C,\mathsf B\mathsf D,\mathsf A\mathsf B \mathsf C,\mathsf A\mathsf B\mathsf D$; the triangle inequality gives the last claims. (b) The Gram kernel of the star, as a function of $(z,z')$, is the average over $(u,v)$ of the product of the two values; by $\E_u\chi(u-z)\chi(u-z')=\one_{z=z'}-q$ (\cref{lem:paley-triple}(b)) it is $(a_1^2+a_2^2)(\one_{z=z'}-q)+a_3^2(\one_{z=z'}-q)^2$, the cross terms containing an isolated average $\E_u\chi(u-\cdot)=0$; as an operator this is $q(a_1^2+a_2^2+a_3^2(1-2q))I+q\bigl(-(a_1^2+a_2^2)+a_3^2q\bigr)\Jproj$, with the stated values on mean-zero functions and on the constants, both at most $q(a_1^2+a_2^2+a_3^2)$. A product on disjoint labels is a tensor product of operators. The induced density of $\nu_F$ relative to three independent labels is $2/Z$ (\cref{lem:record:projection}(b)), and \cref{lem:record:projection}(a) on both halves gives the factor $2/Z$. \end{proof} \begin{lemma}[Conditional collisions]\label{lem:record:conditional-collision} Let $g$ be a polynomial in $\mathsf A,\mathsf B,\mathsf C,\mathsf D$ of degree at most one in each, $M_g$ its maximum modulus on $\{\pm1\}^4$, and $\delta_{ij}$ the indicator of $x_i=y_j$, $i,j\in\{0,1,2\}$. \begin{enumerate}[label=(\alph*)] \item $\|(1-I_\times)g\|\le9M_gq$. \item Fix $(i,j)$. On $\{x_i=y_j\}$ every character becomes $0$, a fixed sign, a function of the free labels of one half only (\emph{one-sided}), or the character of a pair $(x_{i'},y_{j'})$ of free labels (\emph{cross}). After like terms are collected, at most two cross characters remain in each monomial, and they form a single edge, a two-edge star or a two-edge matching. Let $c^{ij}_0(g)$, $c^{ij}_r(g)$, $c^{ij}_q(g)$ be the sums of the absolute coefficients of the monomials with no cross character, with a single cross edge or a two-edge star, and with a two-edge matching. Then $\delta_{ij}g$ is the direct sum over the common value $v$ of $q$ times conditional operators $T^{ij}_v$ between the conditional laws given $x_i=v$ and given $y_j=v$, and $\|T^{ij}_v\|\le\|T^{ij,0}_v\|+(2/Z)(c^{ij}_rr+c^{ij}_qq)$, where $T^{ij,0}_v$, the conditional operator of the no-cross part, has norm at most $c^{ij}_0$. \item With $c_\ast(g)=\sum_{i,j}c^{ij}_\ast(g)$, \[ \|(1-I_\times)g\|\le q\Bigl[c_0(g)+\frac2Z\bigl(c_r(g)r+c_q(g)q\bigr) +\frac{36M_gq}{1-q}\Bigr], \] and $c^{ij}_0(g)$ may be replaced in $c_0(g)$ by any bound for $\sup_v\|T^{ij,0}_v\|$. \item \emph{The reference collision in bundled form.} Let $g=(1+\mathsf A)(1+\mathsf B)$, so that $(1-I_\times)g=\mathsf C_{\rm rem}$ (\cref{lem:old-f-law}(b)), and on a half put $h=\chi(x_1-x_0)$ and $k=\chi(x_2-x_1)$. The no-cross parts of the nine substitutions $\delta_{ij}g$ sum to \[ \begin{aligned} &4\delta_{00}+4\delta_{22}+\delta_{02}+\delta_{20}+\delta_{11}\\ &\quad+\delta_{01}\bigl(1+k(y)\bigr)+\delta_{10}\bigl(1+k(x)\bigr) +\delta_{12}\bigl(1+h(x)\bigr)+\delta_{21}\bigl(1+h(y)\bigr)=qVCV^*, \end{aligned} \] where $V=(V_0,V_1,V_2,kV_1,hV_1)\colon L^2(\Fp)^5\to L^2(\nu_F)$ and $C$ is the symmetric $5\times5$ matrix with diagonal $(4,1,4,0,0)$ and entries $1$ at the positions $01$, $02$, $12$, $03$, $24$ and their transposes. Then $\|C\|\le56119/10000$; on $H_0^5$ the map $V$ has squared norm at most $\Gamma_5=1+2(r+q)/(1-q)+2q(1+r)/((1-q)(1-2q))$; and the constant-input part $q\bigl[15\,\one\otimes\one+\one\otimes(h+k)+(h+k)\otimes\one\bigr]$ of $qVCV^*$ is annihilated by centring on both sides. Consequently, with $Q_\nu$ the projection off the constants in $L^2(\nu_F)$ and $c^\nu_{\rm col}$, $c_{\rm col}$ of \eqref{eq:signed-constants}, $\|Q_\nu\mathsf C_{\rm rem}Q_\nu\|\le c^\nu_{\rm col}q$, and on the $m_0$-centred functions of $L^2(m_0)$ the operator of $\mathsf C_{\rm rem}$ has norm at most $c_{\rm col}q$. \end{enumerate} \end{lemma} \begin{proof} (a) Pointwise $|(1-I_\times)g|\le M_g\sum_{i,j}\delta_{ij}$, and for fixed $x$ each event $y_j=x_i$ has probability $q$, since $y_j$ is uniform; likewise for fixed $y$. The Schur test gives the bound. (b) As $x_i$ and $y_j$ are independent and uniform under $\nu_F\otimes\nu_F$, $\E[\varphi(x)\delta_{ij}g\,\psi(y)]=q\,\E_v\E[\varphi(x)g\,\psi(y)\mid x_i=y_j=v]$ for real $\varphi,\psi$, which is the direct-sum description; Cauchy--Schwarz in $v$ bounds the norm by $q\sup_v\|T^{ij}_v\|$. Given $x_i=v$ the two free labels of $x$ are uniform on a set of $(p-1)(p-2)/2$ pairs, for each $i$ and $v$, so their density relative to two independent uniform labels is $2/Z$, and likewise for $y$. The coincidence removes every edge of the two stars at $x_i$ or $y_j$, and inspection of the nine cases shows that the remaining cross edges are none, a star or a matching. A monomial without a cross character is a product of one-sided factors of modulus at most one, so its conditional operator has rank one and norm at most one. For independent labels a single cross edge, times one-sided factors, has norm at most $r$, a two-edge star at most $(q-q^2)^{1/2}\le r$, and a two-edge matching at most $q$; conjugation by the two square-root densities costs the factor $2/Z$, as in \cref{lem:record:projection}. Values of the kernel off the support of the conditional laws do not matter, so fixed signs may be substituted first. (c) Let $\kappa=\sum_{i,j}\delta_{ij}$. As both halves are injective, simultaneous coincidences form a partial matching between $\{0,1,2\}$ and $\{0,1,2\}$, and $0\le\kappa-\one_{\kappa\ge1}\le\binom\kappa2$, the right side being the sum of $\delta_{ij}\delta_{i'j'}$ over the $18$ unordered pairs of coincidences with $i\ne i'$, $j\ne j'$. Given $x$, the probability that $y$ has two prescribed distinct labels at two prescribed positions is at most $(p-2)/|H_F|=2q^2/(1-q)$. So the kernel $(\kappa-\one_{\kappa\ge1})g$ has row and column sums at most $36M_gq^2/(1-q)$, and the Schur test bounds its norm. Now $(1-I_\times)g=\sum_{i,j}\delta_{ij}g-(\kappa-\one_{\kappa\ge1})g$, and (b) bounds each $\delta_{ij}g$. (d) \emph{Substitutions.} At $x_0=y_0=v$ and at $x_2=y_2=v$ both characters of $g$ equal $1$ (for instance $\mathsf A=\chi(y_2-v)=1$ as $y_0\to y_2$), so $g=4$. At $x_0=y_2$ the character $\mathsf A$ vanishes and $\mathsf B$ stays cross; at $x_2=y_0$, $\mathsf B$ vanishes and $\mathsf A$ stays cross; at $x_1=y_1$ both stay cross. At $x_0=y_1$, $\mathsf A=\chi(y_2-y_1)=k(y)$ is one-sided and $\mathsf B$ stays cross; at $x_1=y_0$, $\mathsf B=\chi(x_2-x_1)=k(x)$; at $x_1=y_2$, $\mathsf A=\chi(x_1-x_0)=h(x)$; at $x_2=y_1$, $\mathsf B=\chi(y_1-y_0)=h(y)$. This gives the displayed no-cross parts, and leaves twelve single cross characters counted with the norms $1$ or $2$ of their one-sided multipliers (one each at $02$ and $20$, two at $11$, two each at $01$, $10$, $12$, $21$) and the two-edge matching $\mathsf A\mathsf B$ at $11$. As operators on $L^2(\nu_F)$, $\delta_{ij}=qV_iV_j^*$ (the label $y_j$ is uniform), and the one-sided factors give $\delta_{01}k(y)=qV_0(kV_1)^*$, $\delta_{10}k(x)=q(kV_1)V_0^*$, $\delta_{12}h(x)=q(hV_1)V_2^*$ and $\delta_{21}h(y)=qV_2(hV_1)^*$; this is $qVCV^*$. \emph{The matrix.} $C$ is nonnegative and symmetric. For the positive vector \[ w=\Bigl(1,\frac{43367}{10^5},1,\frac{17820}{10^5},\frac{17820}{10^5}\Bigr) \] the quotients $(Cw)_a/w_a$ are $561187/10^5$, $243367/43367$, $561187/10^5$, $10^5/17820$ and $10^5/17820$, all below $56119/10000$, so $\|C\|\le56119/10000$. \emph{The synthesis maps.} On $H_0$ every Gram entry $V_a^*V_b$, $a\ne b$, is a translation- and dilation-invariant operator, $\alpha I+\beta P$; fixing the two source labels and summing the third, with $D_0=(p-1)(p-2)$, the ten entries are \[ \begin{array}{c|cccccccccc} ab&01&02&03&04&12&13&14&23&24&34\\\hline \alpha&-\frac1{p-1}&-\frac1{p-1}&\frac1{D_0}&\frac1{D_0} &-\frac1{p-1}&-\frac1{p-2}&-\frac1{p-2}&\frac1{D_0}&\frac1{D_0}&\frac1{p-2}\\[2pt] \beta&-\frac p{D_0}&\frac p{p-1}&\frac p{D_0}&\frac p{p-1} &-\frac p{D_0}&0&0&-\frac p{p-1}&-\frac p{D_0}&0 \end{array} \] (the entries $01$, $02$, $12$ are those of \cref{lem:paley-triple}(d)). As $\|\alpha I+\beta P\|=(\alpha^2+q\beta^2)^{1/2}$ on $H_0$, the entries $02$, $04$, $23$ have norm at most $a_5=(r+q)/(1-q)$ and the others at most $b_5=q(1+r)/((1-q)(1-2q))\le a_5$; every row has at most two entries of the first kind, so by the Schur test $\|V|_{H_0^5}\|^2\le1+2a_5+2b_5=\Gamma_5$. \emph{Centring.} Write $V=V^0+V\Jproj$ with $V^0$ the restriction to $H_0^5$. Then $VCV^*=V^0C(V^0)^*+\sum_{a,b}C_{ab}\,|U_a\rangle\langle U_b|$ with $U=(V_a\one)_a=(\one,\one,\one,k,h)$, and $\sum_{a,b}C_{ab}U_a\otimes U_b$ is the displayed constant-input part. Every $V^0_a$ maps into $\nu_F$-mean-zero functions (for $kV_1$ and $hV_1$ because $\E[k\mid x_1]$ and $\E[h\mid x_1]$ are constant), and $Q_\nu(\cdot)Q_\nu$ annihilates the constant-input part: each of its terms has a constant output or a constant input. Hence $\|Q_\nu(qVCV^*)Q_\nu\|\le q\|C\|\Gamma_5$. The single cross characters and the matching cost at most $(2/Z)(12r+q)q$ by (b), and $(\kappa-\one_{\kappa\ge1})g$ at most $36M_gq^2/(1-q)=144q^2/(1-q)$ by the proof of (c); the certified constant $c^\nu_{\rm col}$ uses $288q/(1-q)$, twice this. So $\|Q_\nu\mathsf C_{\rm rem}Q_\nu\|\le c^\nu_{\rm col}q$. \emph{Actual centring.} Let $\varphi,\psi$ be $m_0$-centred with $\|\varphi\|_{m_0}=\|\psi\|_{m_0}=1$. Then $\|\varphi\|_{\nu_F}\le(1-e_0)^{-1/2}$ and $|\E_{\nu_F}\varphi|=|\E_{m_0}[\varphi(g_0^{-1}-1)]|\le e_0/(1-e_0)$. Split $\varphi$ and $\psi$ into their $\nu_F$-centred parts and their $\nu_F$-means; the centred-centred term is at most $c^\nu_{\rm col}q/(1-e_0)$, and the three terms with a mean are at most $\|\mathsf C_{\rm rem}\|\le17q$ (\cref{lem:old-f-law}(b)(iii)) times $2e_0/(1-e_0)^{3/2}+e_0^2/(1-e_0)^2$. This is $c_{\rm col}q$. \end{proof} \begin{proof}[Proof of \cref{lem:old-f-law}(e),(f)] \emph{Transport.} For a kernel $K$ relative to $\nu_F\otimes\nu_F$, the operator of $K$ on $L^2(m_0)$ is $M_{g_0}^{-1}N_KM_{g_0}^{-1}$, where $M_{g_0}$ is multiplication by $g_0$ and $N_K\psi(x)=\int K(x,y)\psi(y)\,dm_0(y)$ is its \emph{natural} operator (\cref{lem:record:actual-correlation}(b)). As $\|M_{g_0}^{-1}-I\|\le e_0/(1-e_0)$, three rules follow. (T1) The operator has norm at most $\|K\|/(1-e_0)$. (T2) For every operator $N$ on $L^2(m_0)$, $\|M_{g_0}^{-1}NM_{g_0}^{-1}-N\|\le D_g\|N\|$, with $D_g=(2e_0+e_0^2)/(1-e_0)^2$ of \eqref{eq:signed-constants}. (T3) For the constant kernel $\one$, $\Pi_\perp M_{g_0}^{-1}N_{\one}M_{g_0}^{-1}\Pi_\perp$ is the rank-one operator $\ip{g_0^{-1}-\one}{\cdot}_{m_0}(g_0^{-1}-\one)$, of norm $\|g_0^{-1}-\one\|^2_{m_0}\le c_g=e_0^2/(1-e_0)^2$. Moreover, the coordinates of $m_0$ being uniform, the natural operator of a kernel that depends on $y$ only through $y_j$ is $AV^*_{j,m}$, where $A$ has the same kernel as an operator from $L^2(\Fp)$; so $N_{\mathsf L}=V_0PV^*_{2,m}-V_2PV^*_{0,m}=O_0$, and $N_{\mathsf C}=A_2V^*_{0,m}$, $N_{-\mathsf B}=A_1V^*_{0,m}$, $N_{\mathsf B\mathsf C-q}=A_3V^*_{0,m}$, the natural operator of a transposed kernel being the adjoint in $L^2(m_0)$. (f) \emph{The leading operator.} By \cref{lem:actual-features}(a),(b) the pair $(x_0,x_2)$ is uniform on the directed pairs under $m_0$, so $V^*_{0,m}V_2=(P-qI)/(1-q)$ on $H_0$ as under $\nu_F$, and $V_0$, $V_2$ are isometries of $H_0$ into $L^2(m_0)$. \Cref{lem:two-feature-spectrum} therefore applies with the same Gram data as in (b)(i) to $O_0=-(A_1V^*_{0,m}+V_0A_1^{*_m})$: it is self-adjoint, annihilates the constants and has the stated spectrum. In the synthesis of \cref{lem:actual-features}(d), $O_0/r$ is the image of a $4\times4$ matrix of norm one, so $\|O_0\|\le\Gamma_Ar$. \emph{The remainder.} By \cref{lem:old-f-law}(b), $\Psi_0=\Jproj+\mathsf L+\mathsf A\mathsf B-\mathsf C_{\rm rem}$, and $O=\Pi_\perp T_{\rm old}\Pi_\perp$ is $1/z_0$ times the centred operator of $\Psi_0$ on $L^2(m_0)$. In that operator the constant kernel costs $c_g$ by (T3); $\mathsf L$ gives $O_0$ up to $D_g\|O_0\|\le D_g\Gamma_Ar$ by (T2); $\mathsf A\mathsf B$ costs $2q/(Z(1-e_0))$ by (b)(ii) and (T1); and $\mathsf C_{\rm rem}$ costs $c_{\rm col}q$ by \cref{lem:record:conditional-collision}(d). So the centred operator of $\Psi_0$ is $O_0+R'$ with $\|R'\|\le r_oq$, $r_o$ of \eqref{eq:signed-constants}, and its norm is at most $(\Gamma_A+r_or)r$. As $h_0\le z_0\le1$ and $1-z_0\le14q$ (\cref{lem:old-f-law}(a)), $0\le z_0^{-1}-1\le14q/h_0$, and $O=O_0+R'+(z_0^{-1}-1)(O_0+R')=O_0+R_o$ with $\|R_o\|\le r_oq+(14q/h_0)(\Gamma_A+r_or)r=(r_o+n_o)q=e_oq$. Finally $T_{\rm old}=\Jproj+O\succeq O\succeq O_0-e_oqI$, and the smallest eigenvalue $q/(1-q)-(q-q^3/(1-q)^2)^{1/2}$ of $O_0$ is at least $q-r$; so $T_{\rm old}\succeq-(r-q+e_oq)I=-[1+(e_o-1)r]rI$, and $\|O\|\le\Gamma_Ar+e_oq=(\Gamma_A+e_or)r$. (e) For $p\in\Blk$ put $c_p=[1+(e_o(p)-1)r_p]r_p$, with $e_o(p)$ the value of $e_o$ at $(1/p,p^{-1/2})$. By (f) the operator $T_p$ of $K_{0,p}$ on $L^2(m_{0,p})$, the Markov operator of a symmetric coupling of $m_{0,p}$ with itself, is self-adjoint with spectrum in $[-c_p,1]$. The constant $e_o$ is a nondecreasing function of $(q,r)$ and at least $56119/10000>1$ (\eqref{eq:signed-constants} and the remark after it), so $c/r=1+(e_o-1)r$ is nondecreasing, and $c_p\le r_pc_X/r_X\le b^{-1/2}[1+(e_o(X)-1)r_X]$, where $c_X=[1+(e_o(X)-1)r_X]r_X<1$ by hypothesis. By \cref{lem:sector}(c), $\bigotimes_pT_p\succeq-\max_pc_p\,I$ on $L^2(m_{0,\Blk})$. Its form at $\varphi$ is the left side of the inequality, and $\|\varphi\|^2_{m_{0,\Blk}}\le(1+e_X)^{n_X}\int\varphi^2d\nu_{F,\Blk}\le\bar H_X\int\varphi^2d\nu_{F,\Blk}$ by (a), since $\Blk$ has at most $\lfloor L/\log X\rfloor\le n_X$ primes; as $\bar H_Xc_X/r_X=k_{\rm D}(X,L)$, this is the inequality. The cut form at $\iota$ of $\Pi_{F_j}$ at a real half-function is the left side, with $\varphi$ the half-function read through $F_j$, and that of $\operatorname{Diag}_\iota(\Pi^{(1)}_{F_j})$ is $\int\varphi^2d\nu_{F,\Blk}$, because the one-layer fold law is $\nu_{F,\Blk}$ (\cref{lem:record:fold-identification}(b),(d)). \end{proof} \subsection{Prime and block bounds of the signed fold records} \label{subsec:pure-bounds} The leading skew part of a signed fold difference is the three-arm star $L^\circ_{\tlaw,p}$ of \eqref{eq:signed-leading}; the next proposition bounds it, the symmetric part and the remainder, on primes and on blocks. Its constants are the following expressions in $q$, $r$ and $\tlaw$, with $e_0$, $h_0$, $Z$ and $|\mathbf a_\tlaw|$ of \cref{subsec:middle-records:notation}, $\varrho_{02}$, $J_F$ and $\Gamma_A$ of \cref{lem:actual-features}, and $\eta_c=10q$, $h_c=1-\eta_c$, $M_c$ of \cref{lem:signed-components}: \begin{equation}\label{eq:signed-constants} \begin{aligned} &D_g=\frac{2e_0+e_0^2}{(1-e_0)^2},\qquad c_g=\frac{e_0^2}{(1-e_0)^2},\qquad n_c=\frac{18/Z+3}{1-e_0}+\frac{(1+2q)c_g}q,\\ &c_c=\sqrt3\,\Gamma_A+\Bigl(n_c+\frac{D_g}q\sqrt3\,\Gamma_Ar\Bigr)r,\qquad E_c=\frac{10c_cr}{h_c}+\frac{2M_c}q\Bigl(\frac{c_cr}{h_c}+2\varrho_{02}\Bigr),\\ &c_+=\sqrt3\,\Gamma_A+\Bigl(n_c+\frac{D_g}q\sqrt3\,\Gamma_Ar+E_c\Bigr)r,\\ &e_{\rm sg}=\frac{(18-12\tlaw)/Z+k_{\rm col}}{1-e_0}+\frac{(1+2q)c_g}q +\frac{D_g}q\sqrt{3+2\tlaw^2}\,\Gamma_Ar+(1+\tlaw)E_c,\\ &\Gamma_5=1+\frac{2(r+q)}{1-q}+\frac{2q(1+r)}{(1-q)(1-2q)},\qquad c^\nu_{\rm col}=\frac{56119}{10000}\Gamma_5+\frac2Z(12r+q)+\frac{288q}{1-q},\\ &c_{\rm col}=\frac{c^\nu_{\rm col}}{1-e_0} +17\Bigl[\frac{2e_0}{(1-e_0)^{3/2}}+\frac{e_0^2}{(1-e_0)^2}\Bigr],\qquad r_o=\frac2{Z(1-e_0)}+c_{\rm col}+\frac{c_g}q+\frac{D_g}q\Gamma_Ar,\\ &n_o=\frac{14}{h_0}(\Gamma_A+r_or)r,\qquad e_o=r_o+n_o,\qquad s_p=\frac{2|\mathbf a_\tlaw|^2/Z+k_{\rm col}}{1-e_0}+c_{\rm col}+(1+\tlaw)E_c+n_o,\\ &a_p=\frac{2(1+(1-\tlaw)^2)^{1/2}/Z+k_{\rm col}}{1-e_0} +\frac{D_g}q|\mathbf a_\tlaw|\Gamma_Ar+(1+\tlaw)E_c+2(1-\tlaw)J_Fr,\\ &c_{\ge2}=(\Gamma_A+e_or)^2+(1+\tlaw)c_+^2,\qquad s_F=\max(s_p,c_{\ge2}),\qquad a_F=\max(a_p,c_{\ge2}),\\ &\ell_\tlaw=(1+e_0)\biggl[\Bigl(\frac{|\mathbf a_\tlaw|^2+2\tlaw q +2(1-\tlaw)^2q^2/(1-2q)}{1-q}\Bigr)^{1/2}+\frac{(1+\tlaw)q}{1-q}\biggr] +2(1-\tlaw)J_Fq,\\ &s_\tlaw=\bigl(4-2\tlaw+2\tlaw^2+2(1+\tlaw^2)^{1/2}\bigr)^{1/2},\qquad d_\tlaw=s_\tlaw\Gamma_A+(e_o+e_{\rm sg})r, \end{aligned} \end{equation} where $k_{\rm col}=9/4$ if $\tlaw=0$ or $\tlaw\ge2/(p-1)$, and $k_{\rm col}=3$ otherwise. Each expression is built from $q$, $r$ and positive constants by sums, products, maxima and square roots, and reciprocals of the positive decreasing denominators $1-q$, $1-2q$, $1-4q$, $Z$, $h_0$, $h_c$, $1-e_0$ and $1-\varrho_{01}$, after every remainder carrying $q$ has been written as $r$ times an admissible coefficient ($e_0/q$, $D_g/q$, $c_g/q$ and $M_c/q$ are themselves such functions); so for a fixed branch of $k_{\rm col}$ it is a nondecreasing function of $(q,r)$ (\cref{lem:majorant}), and its value at $(q_X,r_X)$, with $q_X=1/X$ and $r_X\ge X^{-1/2}$, bounds its value at every prime $p\ge X$. Also $e_o\ge c_{\rm col}\ge56119/10000$. At $\tlaw=127/500$, $k_{\rm col}=9/4$ for every $p\ge2^{24}$. In words: $c_cr$ bounds the centred norm of an unnormalized positive component, $qE_c$ its normalization and positive completion, $c_+r$ the centred norm of a repaired component; $qe_{\rm sg}$ is the distance of the signed record from its natural leading operator and $qe_o$ that of the reference record (\cref{lem:old-f-law}(f)); $s_pq$ and $a_pq$ are the prime symmetric and skew remainders, $c_{\ge2}/b$ the bound on larger supports, $\ell_\tlaw r$ the leading star, and $d_\tlaw$ the actual coefficient of the direct Gram of the signed record; $s_0=\sqrt6$. \begin{proposition}[Prime and block bounds of the signed fold records] \label{prop:signed-bounds} Let $0\le\tlaw\le1$, let $\Blk$ be a middle block with least prime $b\ge2^{24}$, evaluate the constants of \eqref{eq:signed-constants} at $q=1/b$, $r=b^{-1/2}$, and let $D_\tlaw=T[K_{\tlaw,\Blk}]-\bigotimes_pT_{{\rm old},p}$ be the record difference of $F_1$ on $\Blk$, an operator on $L^2(m_{0,\Blk})$, with $T[\cdot]$ taken relative to $m_{0,\Blk}\otimes m_{0,\Blk}$. \begin{enumerate}[label=(\alph*)] \item $\|\operatorname{Sym}D_\tlaw\|\le s_F/b$. \item $\operatorname{Skew}D_\tlaw=L_{\tlaw,\Blk}+R_{\tlaw,\Blk}$, where $L_{\tlaw,\Blk}$ is $L^\circ_{\tlaw,p}$ on the sector of exact support $\{p\}$, $p\in\Blk$, and zero on the other sectors; $\|L_{\tlaw,\Blk}\|\le\ell_\tlaw b^{-1/2}$ and $\|R_{\tlaw,\Blk}\|\le a_F/b$. The operator $L_{\tlaw,\Blk}$ is the three-arm star $\mathcal A\mathcal V_0^*-\mathcal V_0\mathcal A^*$ of \cref{lem:actual-features}(e) with $(c_1,c_2,c_3)=(1,\tlaw,1-\tlaw)$. \item \emph{One prime.} At a prime $p\ge2^{24}$, with the constants at $(1/p,p^{-1/2})$: $\|D^{\rm s}_{\tlaw,p}\|\le s_pq$, $\|D^{\rm a}_{\tlaw,p}-L^\circ_{\tlaw,p}\|\le a_pq$ and $\|L^\circ_{\tlaw,p}\|\le\ell_\tlaw r$; every centred component $\Pi_\perp T[P_{uv,p}]\Pi_\perp$ has norm at most $c_+r$, and the centred reference $O$ at most $(\Gamma_A+e_or)r$; and the centred signed record is \[ \Pi_\perp T[K_{\tlaw,p}]\Pi_\perp=O_0+L^m_{\tlaw,p}+R^{\rm new}_{\tlaw,p},\qquad L^m_{\tlaw,p}=A_\tlaw V^*_{0,m}-V_0A_\tlaw^{*_m},\qquad \|R^{\rm new}_{\tlaw,p}\|\le e_{\rm sg}q, \] with $O_0$ of \cref{lem:old-f-law}(f) and $A_\tlaw$ unprojected. \item \emph{The inputs of the direct Gram.} On every exact support $S\subseteq\Blk$ with $|S|\ge2$, the restrictions of the centred reference $\bigotimes_pT_{\rm old,p}$ and of the centred signed record have norms with sum at most $c_{\ge2}/b$; and $c_{\ge2}r<21$, $n_Xe_X<1$ and $[1+(e_o-1)r]r<1$; the gates of \cref{lem:record:exact-marginal-e}(ii); and in each piece the inequalities $A^{\rm lead}_{F,i}\ge A^{\rm arm}_{F,i}$ and $A_{E,i}\ge A^{\rm arm}_{E,i}$ between the prices of \cref{subsec:middle-comparison}. The totals of those prices at the exponent $a$ are stored in \path{research/push_2026_10_25/artifacts/author.json} (key \texttt{raw\_totals}); no stored record holds the per-piece constants. A read-only evaluation of the three functions at $X=Q_3=19951586$ ($r_X=1/4466$) gives the following upper bounds: $\Gamma_A<1.0002241$, $R_{\rm row}<7.9840009$, $R_{\rm col}<6.9840008$, $c_+<1.7371505$, $E_c<0.04070887$, $e_{\rm sg}<17.254638$, $c^\nu_{\rm col}<5.6198028$, $c_{\rm col}<5.6198068$, $e_o<7.6238442$, $s_F=s_p<11.166062$, $a_F=a_p<4.7973987$, $c_{\ge2}<4.7880514$, $\ell_\tlaw<1.2731978$, $s_\tlaw<2.3842273$ and $d_\tlaw<2.3903321$; for the matching records $s_E<5.4071859\cdot10^{-4}$, $a_E<1.0000003$, $1/(1-q_X)<1.0000001$, $\kappa^E/r<1.0012128$ and $r_E<10.829703$; and for the cap $n_X=34$, $\bar H_X<1.0000035$, $1+(e_o-1)r_X<1.0014832$ and $k_{\rm D}<1.0014866$. As $q\to0$, $\ell_\tlaw\to|\mathbf a_\tlaw|=1.27319\ldots$ and $d_\tlaw\to s_\tlaw$. Independently, \path{research/advance_2026_10_24/local/check_signed_law.py} checks the polynomial and leading skew identities of \cref{lem:mirror}(d), the exact two-centre Gram and $18$ collision sign patterns, with exact finite checks at small primes; \path{research/advance_2026_10_24/local/check_signed_sharp.py} the factored symmetric and skew identities, the matrix $C$ of \cref{lem:record:conditional-collision}(d) with its exact Schur rows, and exact conditional feature Grams; and \path{research/advance_2026_10_24/local/check_low_domain.py} the uniform analytic majorants and gates from $2^{20}$, for $21$ values of the parameter. \end{certificate} \subsection{The matching records \texorpdfstring{$E_0,E_1$}{E\_0,E\_1} and their replacement \texorpdfstring{$K_1$}{K\_1}}\label{subsec:record:e_side} The two two-layer matching records $E_0,E_1$ of a middle block, of weight $w_{\rm S}r$ each, do not accept the six queries: each needs exactly the cross edge $x_0\to y_1$ (\cref{cert:record:middle-geometry}). They are replaced by an exact-marginal law that imposes this edge and its mirror image $x_1\to y_0$, and nothing else. Unlike the fold records it needs no repair: its fibre count is constant (\cref{lem:record:e-law}(a)). \paragraph{The empty half law.} Let $H_E$ be the set of all halves, $|H_E|=p(p-1)(p-2)$, and $\nu_E$ its uniform law. Kernels are densities relative to $\nu_E\otimes\nu_E$ and operators act on $L^2(\nu_E)$; $V_i$, $\Pi_\perp$, $\top$, $\operatorname{Sym}$ and $\operatorname{Skew}$ are as in \cref{subsec:middle-records:notation}, with $\nu_E$ in place of $\nu_F$. For $i\ne j$ and mean-zero $g$, $\E[g(x_j)\mid x_i]=-g(x_i)/(p-1)$, so the Gram operator of $V=(V_0,V_1,V_2)$ on $H_0^3$ is $(1+u)I-uJ_3$, with $u=1/(p-1)$ and $J_3$ the all-ones $3\times3$ matrix; its eigenvalues are $1+u=1/(1-q)$ and $1-2u=(1-3q)/(1-q)$. Every pair of coordinates of $\nu_E$ is uniform on the distinct pairs, of density $1/(1-q)$, and $\nu_E$ has density $1/Z$ (\cref{lem:record:projection}(b)); \cref{lem:record:projection}(a) applies with these bounds. Write $\delta_{\mathsf C}=\one[x_1=y_0]$, $\delta_{\mathsf D}=\one[x_0=y_1]$ and $\delta_{ij}=\one[x_i=y_j]$. At $\iota$ the reference's two-layer matching record is the uniform law of pairs of disjoint halves, $K^E_0=I_\times/z^E_0$, with both half marginals $\nu_E$ (\cref{lem:record:fold-identification}(d)). \begin{lemma}[The exact-marginal matching law]\label{lem:record:e-law} Let $p\ge19$ and $z_1=(p^2-3p+4)/(p(p-1))$. \begin{enumerate}[label=(\alph*)] \item The kernel $K_1=(1+\mathsf C-\delta_{\mathsf C})(1+\mathsf D-\delta_{\mathsf D})/z_1$ is the density of a $\mathcal G_p$-invariant probability measure on $H_E\times H_E$ whose two half marginals both equal $\nu_E$. It is $4/z_1$ times the indicator of the strict edges $x_1\to y_0$ and $x_0\to y_1$ and imposes no other relation between the halves; in particular other coincidences between the halves, such as $x_2=y_2$, have positive probability. Under it each of the pairs $(x_0,y_1)$ and $(x_1,y_0)$ is uniform on the strict-square pairs. \item $z^E_0=(p-3)(p-4)(p-5)/(p(p-1)(p-2))\ge1-9q$, and on mean-zero functions $K^E_0$ has norm at most $k^E_{\rm old}=9q/(1-9q)$; its exact value there is $3/(p-3)$ (\cref{sec:frontier:empty-triple-negative}). Moreover $z_1\ge1-2q$ and $00$ and total variation $|\nu|_\Blk\le\nu_\Blk(1)+2\tlaw w$; it satisfies (a) of \cref{def:record:comparison-law}, and its changes satisfy (b) there with norm envelopes $\operatorname{Diag}_\iota$ of their actual half marginals and prices \[ s_\Blk\le\bigl(S_2r^2+S_3r^3+S_4r^4+S_5r^5\bigr)q_\Blk^{2a},\qquad a_\Blk\le\bigl(A_2r^2+A_3r^3+A_4r^4\bigr)q_\Blk^{2a}, \] where \begin{align*} S_2&=2w_{\rm S}s_E,& A_2&=2w_{\rm D}\ell_\tlaw+2w_{\rm S}a_E,\\ S_3&=2w_{\rm D}s_F+6v_{\rm R}+2v_{\rm D}(f_1+h_1),& A_3&=2w_{\rm D}a_F+w_{\rm R}g_{\rm A},\\ S_4&=2v_{\rm C}+w_{\rm R}g_{\rm S},& A_4&=\frac{2w_{\rm C}}{1-q_X},\\ S_5&=\frac{2w_{\rm C}}{(1-q_X)^2}.&& \end{align*} with $s_F,a_F,\ell_\tlaw$ of \eqref{eq:signed-constants} (\cref{prop:signed-bounds}), $s_E=s_E(X)$, $a_E=a_E(X)$ of \cref{lem:record:exact-marginal-e}(ii), and $g_{\rm S}=g_{\rm S}(X)$, $g_{\rm A}=g_{\rm A}(X)$ of \cref{cor:merge-repair}. The auxiliary prices (\cref{def:cp5}) of the skew change of each of the two fold records are, times $q_\Blk^{2a}$, the raw-arm price $w_{\rm D}r^2$, the leading price $w_{\rm D}\ell_\tlaw r^2$ and the remainder price $w_{\rm D}a_Fr^3$; those of each of the two matching records are $w_{\rm S}r^2$, $w_{\rm S}r^2/(1-q_X)$ and $w_{\rm S}r_Er^4$, with $r_E=r_E(X)$ of \cref{lem:oct24:matching-star}. Summed over the two records of each kind they are $2w_{\rm D}r^2$, $2w_{\rm D}\ell_\tlaw r^2$, $2w_{\rm D}a_Fr^3$ and $2w_{\rm S}r^2$, $2w_{\rm S}r^2/(1-q_X)$, $2w_{\rm S}r_Er^4$. Every selected law of these changes is admissible (\cref{def:admissible}). \end{lemma} \begin{proof} Dividing by $\widetilde\mu_\Blk(1)\ge1$ only decreases the weights, so it suffices to charge the unnormalized ones. \emph{Decomposition and (a).} The records of $\lambda_\Blk$ that the comparison law keeps, the replacements of the matching and merge records, the accepting two-layer constants, and the components $\bigotimes_pP_{++,p}$, $\frac\tlaw2\bigotimes_pP_{-+,p}$ of the two signed records are nonnegative measures; their sum is $\nu^+_\Blk$, and $\nu_\Blk(1)=\nu^+_\Blk(1)-\tlaw w$, which gives the total variation. The two-layer root has weight one in $\widetilde\mu_\Blk$ and is retained, so $\nu^+_\Blk(1)\ge1/\widetilde\mu_\Blk(1)$ and $\nu_\Blk(1)\ge(1-\tlaw w_{\rm D}r)/\widetilde\mu_\Blk(1)>0$, as $w_{\rm D}<6$ (\cref{rem:middle-weights}, \cref{tab:data:middle-weights}) and $r<2^{-12}$. Every record and component is invariant under independent square-affine maps at the primes of $\Blk$ (\cref{lem:signed-components}(a),(d), \cref{lem:record:e-law}(a), \cref{cor:merge-repair,lem:record:accepting-c2}; for the unchanged records \cref{lem:front12:reference} and \cref{lem:record:one-stage-folded-e}), so its one-slot marginals are uniform and its queried pairs are its mass times the uniform law on strict-square pairs; and each accepts the six queries, as listed above. This is (a) and the clause \ref{it:record:R5} for each of the three components. \emph{Prices.} Each replacement has the same actual half marginals on both halves of $\iota$ as the record it replaces, so \cref{rem:cp:charging}(ii) charges it its weight times the norms of the symmetric and skew parts of the difference; for the signed records the proof of (ii) uses only that the new record has mass one and the half marginals of the old one, not that it is nonnegative. The two fold records cost at most $w_{\rm D}r\cdot s_Fr^2$ and $w_{\rm D}r\cdot(\ell_\tlaw r+a_Fr^2)$ each (\cref{prop:signed-bounds}(a),(b),(e)), the two matching records $w_{\rm S}r\cdot s_Er$ and $w_{\rm S}r\cdot a_Er$ each (\cref{lem:record:exact-marginal-e}(ii)), and the six merge records together $w_{\rm R}g_{\rm S}r^4$ to the symmetric part and $w_{\rm R}g_{\rm A}r^3$ to the skew part (\cref{cor:merge-repair}). The two-layer constants add $S_5r^5$ and $A_4r^4$, respectively (\cref{lem:record:accepting-c2}). The deleted records are charged their masses to the symmetric part (\cref{rem:cp:charging}(i)). The skew change of a fold record splits into its leading three-arm star, of norm at most $\ell_\tlaw r$ with arms of norm at most $r$ (\cref{prop:signed-bounds}(b), \cref{lem:actual-features}(e)), and a remainder of norm at most $a_Fr^2$; that of a matching record into its one-arm star, of norm at most $r/(1-q_X)$ with arm norm at most $r$, and a remainder of norm at most $r_Er^3$ (\cref{lem:oct24:matching-star}); times the weights these are the auxiliary prices. The coefficients are evaluated at the piece start and bound the norms at every block of the piece (\cref{lem:majorant}, the constants being nondecreasing in $(q,r)$), and the weights and the row constants $f_1,h_1$ are those of the piece (\cref{lem:record:local-domain}(iii)). \emph{Admissibility.} The changes are invariant signed measures on the field labels only, independent of the indices, so (O1) holds; and the only operator bounds applied to them are their own norms at $\iota$, with no shared label, so (O2) holds. \end{proof} Summing over the blocks of each piece with the charges of \cref{lem:record:block-charge} and over the pieces gives the middle parts of $S$ and $A$ and the totals of the auxiliary prices directly. In the piece $i$, with start $X_i$, weights $w_{{\rm D},i}=w_{{\rm S},i}$, the coefficients of \cref{lem:middle-comparison-prices} at $X_i$, and the certified degree charges $\bar I_{d,i}\ge\sum_\Blk b_\Blk^{-d/2}q_\Blk^{2a_0}$ of \cref{tab:record:middle-pieces}, the prices at the anchor $a_0$ are \begin{equation}\label{eq:middle-piece-prices} \begin{aligned} &A^{\rm arm}_{F,i}=\operatorname{up}(2w_{{\rm D},i}\bar I_{2,i}),\quad A^{\rm lead}_{F,i}=\operatorname{up}(2w_{{\rm D},i}\ell_\tlaw(X_i)\bar I_{2,i}),\quad A^{\rm rem}_{F,i}=\operatorname{up}(2w_{{\rm D},i}a_F(X_i)\bar I_{3,i}),\\ &S_{F,i}=\operatorname{up}(2w_{{\rm D},i}s_F(X_i)\bar I_{3,i}),\qquad A_{F,i}=A^{\rm lead}_{F,i}+A^{\rm rem}_{F,i},\\ &A^{\rm arm}_{E,i}=\operatorname{up}(2w_{{\rm S},i}\bar I_{2,i}),\quad A^{\rm lead}_{E,i}=\operatorname{up}\Bigl(\frac{2w_{{\rm S},i}\bar I_{2,i}}{1-q_{X_i}}\Bigr),\quad A^{\rm rem}_{E,i}=\operatorname{up}(2w_{{\rm S},i}r_E(X_i)\bar I_{4,i}),\\ &A_{E,i}=2\operatorname{up}(w_{{\rm S},i}a_E(X_i)\bar I_{2,i}),\qquad S_{E,i}=\operatorname{up}(2w_{{\rm S},i}s_E(X_i)\bar I_{2,i}),\\ &S_{{\rm oth},i}=\sigma_{s,i}+S^{\rm oth}_{3,i}\bar I_{3,i} +S_{4,i}\bar I_{4,i}+S_{5,i}\bar I_{3,i}/X_i,\\ &A_{{\rm oth},i}=\sigma_{a,i}+w_{{\rm R},i}g_{\rm A}(X_i)\bar I_{3,i} +A_{4,i}\bar I_{4,i}, \end{aligned} \end{equation} with $\operatorname{up}(x)=10^{-30}\lceil10^{30}x\rceil$ and $S^{\rm oth}_3=S_3-2w_{\rm D}s_F=6v_{\rm R}+2v_{\rm D}(f_1+h_1)$. Here $\sigma_{s,i},\sigma_{a,i}\in[0,10^{-30})$ are the rounding slacks of the corresponding merge and two-layer-constant rows of the authenticated middle-price source named in \cref{def:closing-quantities}(3): each is its stored upward rounding minus its exact unrounded expression. Keeping these slacks makes the update an exact rational replacement of the two-layer constant and merge contributions as stored there. The degree-five charge needs no new prime enumeration, since $b^{-5/2}\le X_i^{-1}b^{-3/2}$. The totals at the exponent $a$ are $t$ times the sums over the $33$ pieces, $t=e^{2(a-a_0)L}$ with $L=570$ (\cref{lem:record:repricing}, \cref{def:closing-quantities}): $A^{\rm arm}_F=t\sum_iA^{\rm arm}_{F,i}$ and so on for $A^{\rm lead}_F$, $A^{\rm rem}_F$, $A_F$, $S_F$, $A^{\rm arm}_E$, $A^{\rm lead}_E$, $A^{\rm rem}_E$, $A_E$, $S_E$, $S_{\rm oth}$ and $A_{\rm oth}$, with the middle totals $S_{\rm mid}=S_F+S_E+S_{\rm oth}$ and $A_{\rm mid}=A_F+A_E+A_{\rm oth}$. The merge and constant replacements have different symmetric and skew prices, as displayed in \eqref{eq:middle-piece-prices}. The full skew price $A_E$ of the matching records is bounded directly; $A_F$ is the sum of the leading and remainder prices, and $A^{\rm lead}_F\ge A^{\rm arm}_F$, $A_E\ge A^{\rm arm}_E$ (\cref{cert:signed-local}). At the density-linear baseline exponent $a=\PushA$, the following conservative upper totals remain valid: the generic symmetric and skew prices $S_{{\rm oth},i}$ and $A_{{\rm oth},i}$ in \eqref{eq:middle-piece-prices} are each no larger than the corresponding generic rows of \cref{def:closing-quantities}(3). The totals at $a$, which are the baseline totals used in \cref{sec:closing}, are $A^{\rm arm}_F=A^{\rm arm}_E<0.42332183839047$, $A^{\rm lead}_F<0.53897233394172$, $A^{\rm rem}_F<0.00005658950959$, $A_F<0.53902892345131$, $A^{\rm lead}_E<0.42332183982722$, $A^{\rm rem}_E<1.436778E-8$, $A_E<0.42332184557419$, $S_F<0.00013191008864$, $S_E<0.00003092662078$, $S_{\rm oth}<0.00052581574396$, $A_{\rm oth}<0.00023870593198$, $S_{\rm mid}<0.00068865245337$ and $A_{\rm mid}<0.96258947495747$ (\path{research/push_2026_10_25/artifacts/author.json}, key \texttt{raw\_totals}; \cref{tab:data:prices}). The final construction uses the smaller prices in \eqref{eq:middle-piece-prices} and also retains the common reference normalization; its complete new totals are given in \cref{sec:four-routes-closing}. \paragraph{Consequences and what to read next.} From Part~II: \cref{lem:majorant} (evaluation at the piece start), \cref{lem:sector} (sectors of block differences, Markov tensor maximum, the closing clause of (b) and the two-support step (h)) and \cref{rem:signed-mixture-sectors} (signed sums of products), \cref{def:admissible}, and the Weil bound \cref{thm:weil}. From Part~III: the signed comparison laws of \cref{def:cp4}, the auxiliary prices of \cref{def:cp5}, the charging rules \cref{rem:cp:charging}, the energy toolkit \cref{lem:energy-toolkit} (for \cref{lem:record:old-f-marginal}(d)), \cref{lem:record:repricing}. From Part~IV: \cref{lem:record:fold-identification} (the records at $\iota$ and their half marginals), \cref{lem:paley-triple} (Paley counts, the Paley operator, directed triples and their features), \cref{lem:spec:affpair} (invariant functions), \cref{lem:extension,lem:graphs:sequential} (count errors), \cref{sec:frontier:empty-triple-negative} (the disjoint-triple operator), \cref{prop:middle-negative,cor:influence-schur} (correlations of the merge graph laws), \cref{lem:record:actual-correlation,lem:record:projection} (actual marginals, projected kernels), and the repair package \cref{lem:tr:repair,cor:markov-completion}. From \cref{sec:middle-reference,sec:middle-frame}: the reference (\cref{lem:front12:reference}) and its weights (\cref{rem:middle-weights}), the frame (\cref{def:record:frame}), the block charges, the local domain and the recorded F21 caps (\cref{lem:layer12-caps}); from \cref{sec:positive-roots}, the support of the positive root. Data and certificates: \cref{cert:record:middle-geometry,cert:signed-local,cert:merge-coefficients,cert:record:old-f-cap,cert:record:e-coefficients}; the totals of \cref{tab:data:prices}. \paragraph{Hypotheses verified in this section (\cref{tab:hypotheses}).} (CP4) for the middle atoms, that is, the signed decomposition of $\nu_\Blk$ into nonnegative accepting components with uniform one-slot marginals, its variation and \ref{it:record:R5}, and the brackets of every change with the prices and auxiliary prices of \cref{lem:middle-comparison-prices}; the negative cap $k_{\rm D}=k_{\rm D}(X,L)$ used in (CP1) for the middle atoms (\cref{lem:old-f-law}(e)); the centred norm $\kappa_F$ used by the variance credits (\cref{lem:record:old-f-marginal}); the direct-Gram coefficient $d_\tlaw$ (\cref{prop:signed-bounds}(d)); and the admissibility clause (CP8)(a) for the changes of the middle records. \space % End sections/21_middle_records % Begin sections/22_variance \section{The variance identity: savings \texorpdfstring{$D_{\mathrm{var}}$}{D\_var} from fixed marginals}\label{sec:variance} \paragraph{What this section proves and how to read it.} When a replacement keeps the same one-half marginals, its energy against $\Nbr$ equals a diagonal energy minus a product energy (a variance). The trivial bound keeps only the diagonal ($\le BC_XY$); this section bounds the product energy below by $gC_XY$, giving the improved class bound $B-g$ allowed by (CP5). The total saving $D_{\rm var}$ is subtracted in $\Theta$ as $(63/64)D$ (a \emph{saving}, called a \emph{credit} in the text; the word \emph{coupon} below means one proved term in a single coefficient: a subtracted saving $g$ for price coefficients, or an added energy lower bound for the mean constant $m$). Four records per middle block are treated (\emph{eligible} means: replaced at fixed marginals and annihilating constants). Reading-order note: the final $D_{\rm var}$ in \cref{cor:variance:final} uses dominator caps from \cref{sec:envelopes}, and \cref{sec:envelopes} in turn uses the variance savings for aligned classes; the per-block inequalities here do not depend on \cref{sec:envelopes}, only the final assembly does---read the two sections as: per-block identities first, assembly last. Inputs: \cref{sec:middle-records}. Output: $D_{\rm var}>0.0099$ (baseline). The lower bounds are not positive semidefinite orders at $\iota$. They restore the product energy from the root of the reference in four steps. (A) At the chamber cut of the fold that produces the record, the actual half law of the root and the law induced by the record are mutually absolutely continuous, with a pointwise density bound and a chi-square bound (\cref{lem:record:root-marginal}; for the positive roots of the late pieces, \cref{lem:record:root-marginal}(iv)); the chi-square bound rests on the second moment of a neighbourhood count, which a modular evaluation of a character sum makes small (\cref{lem:record:weighted-moment}). (B) The root is a probability coupling at that cut, so its energy is at most that of its own half diagonal; step (A) compares that diagonal with the record. (C) The reference is a positive mixture of the root and of laws of controlled energy, so a stated positive fraction of $Y$ is recovered from the root energy (\cref{lem:record:restoration}). (D) At the reserved cut the record's own Markov operator, in its own actual marginal space, has centred norm $k_\phi<1$ (\cref{subsec:variance:centred}), i.e. it is a contraction towards the projection onto constants. The two matching records are not folds; they are reached from the two fold records by a polarization at the chamber cut $\vartheta_0$ (\cref{lem:record:paired-e-bridge,lem:record:paired-e-joint}). \Cref{lem:var-gain} turns the four steps into a gain. For a selected matching product the exterior bracket adds positive background terms, which a joint restoration bounds below (\cref{prop:background-variance}). The energies $Y[\kappa]$, $Y^{\Nbr}[\kappa]$, $Y^{\Nbrz}[\kappa]$ of selected laws, the price $C_X=\prod_{\Blk\in X}q_\Blk^{2a}$, the diagonal copies $\operatorname{Diag}_\vartheta$, the product laws $J_\vartheta$ and the relations \ref{it:record:E1}--\ref{it:record:E3}, \ref{it:record:P1}--\ref{it:record:P4} and \ref{it:record:P3b} are those of \cref{sec:comparison-lemmas} (\cref{lem:energy-toolkit}); $Y=Y_\mu$. \subsection{The four records treated here}\label{subsec:variance:eligible} The variance saving applies to only four records of a middle block: the two nonaligned folds $F_1,F_2$ and the two matchings $E_0,E_1$, called the \emph{eligible} records. Each is replaced by a law with exactly the same actual half marginals at $\iota$, so the difference annihilates constants and part of its price can be recovered as a variance, as the following subsections show. This subsection fixes the four laws, their actual half marginals, and the two comparison laws---the diagonal copy and the product of the marginals---between which the variance is measured. Let $\Blk$ be a middle block (\cref{def:record:exact-blocks}) with least prime $b=b_\Blk$, and put $r=r_\Blk=b^{-1/2}$ and $q=r^2$. We write $x\to y$ if $\chi(y-x)=1$ at every prime of $\Blk$; the laws below are products over the primes of $\Blk$ of the laws at one prime. We use the components of the reference of $\Blk$ (\cref{subsec:middle-reference-law}): the \emph{two-layer $F$ law} $\lambda_F$, uniform on six distinct labels $(y_{o,\ell})_{o\in\{0,1,2\},\,\ell\in\{0,1\}}$ with $y_{0,\ell}\to y_{2,\ell'}$ for all $\ell,\ell'$, and the \emph{two-layer $E$ law} $\lambda_E$, uniform on six distinct labels; a map $\phi\colon\Z/6\Z\to\{0,1,2\}$ places the label $y_{\phi(u),\ell}$ at the six slots $(u,v,\ell)$, $v\in\Z/6\Z$; the type-$\rm D$ components $\Pi_{F_j,\Blk}$ are the images of $\lambda_F$ under the folds $F_j$ of \cref{def:patterns}, of weight $w_{\rm D}r$ each in $\widetilde\mu_\Blk$, and the type-$\rm S$ components $\Pi_{E_s,\Blk}$ the images of $\lambda_E$ under the matchings $E_s$, of weight $w_{\rm S}r$ each; and the \emph{root} $\Pi_{\mathrm L,\Blk}$ is the uniform law on twelve distinct labels $(y_{u,\ell})_{u\in\Z/6\Z,\,\ell\in\{0,1\}}$ with $y_{u,\ell}\to y_{\rot u,\ell'}$ for all $u,\ell,\ell'$, which contains all four layer lifts of the six directed edges $0\to2\to4\to0$ and $1\to5\to3\to1$; this is the root of the blocks of the pieces starting below $2^{30}$. On the seven pieces starting at $2^{30},2^{31},2^{32},2^{34},2^{36},2^{40},2^{45}$ the root is the positive root $\Gamma_{\Blk,\ulaw}$ of \cref{def:positive-root}, a positive reweighting of the uniform law with the same support; it is invariant under the chamber automorphisms used below, the layer interchange and independent square-affine maps at the primes of $\Blk$ (\cref{lem:positive-root-properties,lem:imp:coherent39-law}), and every statement of this section about the root holds for it, with the density and chi-square bounds of its half law given by \cref{lem:record:root-marginal}(iv) in place of (i)--(iii). For $j\in\{0,1,2\}$ the \emph{fold chamber} of $F_j$ is the chamber cut $\vartheta_{2j}$ of the first coordinate, in the notation of \cref{subsec:chamber-geometry}: its reflection is $u\mapsto4j-1-u$ (that is $5-u$, $3-u$ and $1-u$) and its plus half is $H_{2j}=\{2j,2j+1,2j+2\}$ (indices mod $6$). By \cref{lem:record:fold-identification}(a)--(d): the root is invariant under the chamber automorphisms (for a positive root by \cref{lem:positive-root-properties}(b) and \cref{lem:imp:coherent39-law}), so at each $\vartheta_{2j}$ it couples two copies of one half law $\nu_{\mathrm L,\Blk}$, which, read in the order $(2j,2j+1,2j+2)$, lives on the support of $\lambda_F$ and does not depend on $j$; $\Pi_{F_j,\Blk}=\operatorname{Diag}_{\vartheta_{2j}}(\lambda_F^{(j)})$, where $\lambda_F^{(j)}$ places the labels of the object $o$ at the object $2j+o$; and at $\iota$ the records $\Pi_{F_j,\Blk}$, $\Pi_{E_s,\Blk}$ are symmetric, with actual half marginal the layer-zero triple law of $\lambda_F$ placed by $F_j$, respectively the uniform law on ordered triples of distinct labels placed by $E_s$. \begin{definition}[Eligible records and repairs]\label{def:record:eligible} The \emph{eligible records} of a middle block $\Blk$ are $\phi\in\{F_1,F_2,E_0,E_1\}$. For such $\phi$ let $\Pi_{\phi,\Blk}$ be the normalized reference record, $m_{\phi,\Blk}$ its actual half marginal at $\iota$ (the same on both halves), $D_{\phi,\Blk}=\operatorname{Diag}_\iota(m_{\phi,\Blk})$ its \emph{selected diagonal}, and $J_{\phi,\Blk}$ the law under which the two $\iota$-halves are independent, each with law $m_{\phi,\Blk}$ (the \emph{product of the actual half marginals}). A \emph{repair} of $\phi$ is a signed measure $\Pi'_{\phi,\Blk}$ of mass one on the labels of $\Blk$ that is a finite real combination of nonnegative measures, each invariant under independent square-affine maps at the primes of $\Blk$ and with the actual half marginal $m_{\phi,\Blk}$ on both sides of $\iota$. The \emph{record difference} $\Delta_{\phi,\Blk}$ is the operator on $L^2(m_{\phi,\Blk})$ with \[ \ip{\psi}{\Delta_{\phi,\Blk}\psi'}_{m_{\phi,\Blk}} =\int\psi(z_+)\psi'(z_-)\,d(\Pi'_{\phi,\Blk}-\Pi_{\phi,\Blk})(z), \] and $\Delta^{\rm s}_{\phi,\Blk}$, $\Delta^{\rm a}_{\phi,\Blk}$ are its symmetric and skew parts. In the comparison law of the middle range the repair of $F_j$ is the signed whole-block fold record of \cref{def:record:mixture}(c),(d), a combination of three positive product laws, each with both half marginals $m_{F_j,\Blk}$ (\cref{lem:signed-components}), and the repair of $E_s$ is the exact-marginal matching law of \cref{lem:record:e-law}, tensorized over the primes of $\Blk$ (\cref{lem:record:exact-marginal-e}). \end{definition} Both $\Pi_{\phi,\Blk}$ and its repair have the actual half marginal $m_{\phi,\Blk}$ on both sides of $\iota$, so \begin{equation}\label{eq:record:zero-marginal} \Delta_{\phi,\Blk}\one=\Delta_{\phi,\Blk}^*\one=0,\qquad \Delta_{\phi,\Blk}=(I-\Jproj)\Delta_{\phi,\Blk}(I-\Jproj), \end{equation} where $\Jproj$ is the projection onto the constants of $L^2(m_{\phi,\Blk})$; the same holds for $\Delta^{\rm s}_{\phi,\Blk}$ and $\Delta^{\rm a}_{\phi,\Blk}$. The record of weight $w_\phi\in\{w_{\rm D}r,w_{\rm S}r\}$ contributes $w_\phi(\Pi'_{\phi,\Blk}-\Pi_{\phi,\Blk})$, normalized by $\widetilde\mu_\Blk(1)\ge1$, to $\nu_\Blk-\lambda_\Blk$: the first stage changes only the one-layer folded records (\cref{def:record:frame}), so the two-layer records enter $\lambda_\Blk$ and $\mu_\Blk$ with the same weight. In the per-record decomposition of \cref{def:record:comparison-law}(b) its norm envelopes are $\tilde\pi^{\rm s}D_{\phi,\Blk}$ and $\tilde\pi^{\rm a}D_{\phi,\Blk}$ for any $\tilde\pi^{\rm s}\ge w_\phi\|\Delta^{\rm s}_{\phi,\Blk}\|$ and $\tilde\pi^{\rm a}\ge w_\phi\|\Delta^{\rm a}_{\phi,\Blk}\|$ (\cref{rem:cp:charging}(ii)), with prices $\tilde\pi^{\rm s}q_\Blk^{2a}$ and $\tilde\pi^{\rm a}q_\Blk^{2a}$; the norm bounds are those of \cref{prop:signed-bounds} for $F_j$ and of \cref{lem:record:exact-marginal-e} for $E_s$. The two records of one kind in a block have differences of equal symmetric and skew norms: that of $F_2$ is $UD^*U$, with $D$ that of $F_1$ and $U$ a self-adjoint unitary, so that its symmetric and skew parts are $UD^{\rm s}U$ and $-UD^{\rm a}U$ (\cref{def:record:mixture}(d), \cref{prop:signed-bounds}(e)), and $E_0$, $E_1$ place one and the same law. So the two fold records of a block carry the same prices, and so do its two matching records. Every positive law constructed in this section (the records, their repairs, their diagonals and their products) is a positive measure, invariant under independent translations at the primes of its blocks, whose normalization has uniform one-slot marginals and does not depend on the indices (O1); the only operator-norm bounds at a cut applied to these laws, the contraction ($d=1$) of a probability coupling and the centred norms of a record's own Markov operator at $\iota$, condition on no shared label (O2). So the laws are admissible (\cref{def:admissible}), and \ref{it:record:E1}--\ref{it:record:E3} apply to them. The comparison at the fold chamber of $F_j$ is the following statement. \begin{hypothesis}[Root density, (A)]\label{hyp:variance:A} For $j\in\{1,2\}$, at the fold chamber $\vartheta_{2j}$ of $F_j$ (reflection $u\mapsto3-u$ for $F_1$, $u\mapsto1-u$ for $F_2$), the actual half law $\nu_{\mathrm L,\Blk}$ of the root on the objects $H_{2j}$ and the law $\lambda_F^{(j)}$, whose $\vartheta_{2j}$-diagonal copy is the record $\Pi_{F_j,\Blk}$, satisfy $M_\Blk^{-1}\le d\nu_{\mathrm L,\Blk}/d\lambda_F^{(j)} \le M_\Blk$. \end{hypothesis} \Cref{lem:record:root-marginal} proves hypothesis (A) with an explicit $M_\Blk$, for the uniform root in (i)--(iii) and for the positive roots of the late pieces in (iv), and also bounds the chi-square divergence of the two laws. The record compared with the root is the two-layer record itself, which the first stage does not change, not its reserved-cut marginal. The comparison is made at a chamber cut because no comparison is available at $\iota$: there the half laws of the folded records are singular to that of the root, and no positive semidefinite order at $\iota$ bounds the product energy from below (\cref{rem:record:variance-n1}). \subsection{Comparing the principal half law with the record half law}\label{subsec:variance:root} Restoration needs the chi-square distance between two half laws at a chamber cut: the half law of the principal (root) record and the half law of an eligible record. At one prime this distance is governed by the second moment of a signed neighbourhood count--- how many common neighbours, with prescribed signs, four labels have. That second moment is computed first; one of the graph moments in it is evaluated through the Ahlgren--Ono identity (\cref{thm:ahlgren-ono}), the others by Weil's bound. At one prime $p\equiv3\pmod4$ we use $q=1/p$, $r=p^{-1/2}$ and $k_p=(p-3)/4$, the exact number of common successors, and of common predecessors, of two distinct elements of $\Fp$ (\cref{lem:paley-triple}(a)). Signed neighbourhoods of four distinct labels and their soft counts $\mathfrak S$ are those of \cref{lem:record:signed-nbhd}: with $\upsilon_+=11r+6q$ and $\upsilon_-=11r+70q$, a signed neighbourhood has between $\frac p{16}(1-\upsilon_-)$ and $\frac p{16}(1+\upsilon_+)$ elements, and at least $\frac p{16}(1-\upsilon_\times)$ of them avoid two further labels, where \[ \upsilon_\times=\upsilon_-+32q=11r+102q . \] \paragraph{The second moment of a neighbourhood count.} The chi-square comparison needs the second moment of the fluctuation of a neighbourhood count. For independent uniform $x=(x_1,x_2,x_3,x_4)\in\Fp^4$ and the signs $s=(-1,-1,1,1)$ put $s_A=\prod_{i\in A}s_i$ and \[ \mathcal W=\sum_{\substack{A\subseteq\{1,2,3,4\}\\|A|\in\{3,4\}}}s_A \sum_{z\in\Fp}\prod_{i\in A}\chi(z-x_i),\qquad P_{\rm adm}=\prod_{i\in\{1,2\},\ k\in\{3,4\}}\bigl(1+\chi(x_k-x_i)\bigr). \] For a finite simple graph $G$ on $\{0,\dots,n-1\}$ let $M_G=\E\prod_{\{u,v\}\in G,\,u0$ and $|M_{G_{10}}|\le qr$, its right side is at most $5q+34qr+11q^3$ minus $8q^2-2q^3+10q^4+4q^2r+6q^3r$, which is nonnegative. \end{proof} \begin{remark}[The crude second moment]\label{rem:variance:crude} The identity matters only for its constant. Under independent uniform labels only the diagonal pairs $A=A'$ survive in $\E[\mathcal W^2]$, because $\E_x\chi(z-x)=0$, and $\E_x\chi(z-x)\chi(z'-x)=\one[z=z']-q$; hence $\E[\mathcal W^2]=\sum_{|A|\in\{3,4\}}[p(1-q)^{|A|}+p(p-1)(-q)^{|A|}]\le5p$, and $0\le P_{\rm adm}\le16$ gives $\E[P_{\rm adm}\mathcal W^2]/p^2\le80q$. This already shows that the chi-square divergence of \cref{lem:record:root-marginal} is $O(q)$. The identity lowers the constant from $80$ to about $10$, and the modular evaluation of \cref{lem:record:weighted-moment}(b) to about $5$; the certified credits use the latter. \end{remark} \paragraph{The first moment of the four-root count.} The cut L20 of the uniform root (\cref{subsec:middle-l20}) needs the first moment of the same signed count, with the four labels distinct. Write $\mathcal W=\mathcal W_3+\mathcal W_4$, where $\mathcal W_k$ is the part of $\mathcal W$ with $|A|=k$, and let $D_4$ be the indicator that $x_1,\dots,x_4$ are distinct. \begin{lemma}[The first moment of the four-root count]\label{lem:l20-star-mean} Let $p\equiv3\pmod4$ be prime. Then \begin{equation}\label{eq:l20-star-identities} \frac{\E[P_{\rm adm}D_4\mathcal W_3]}p=0,\qquad \frac{\E[P_{\rm adm}D_4\mathcal W_4]}p=M_{G_5}+8q^2-33q^3+25q^4 . \end{equation} Consequently, let $p>7$, so that $Z_4=(1-q)(1-3q)(1-7q)>0$, and let $\mathsf K$ be the soft kernel of the cut L20 of \cref{subsec:middle-l20}, the product over the sixteen cross edges of the factors $1+(D_{20})_{ij}\chi(x'_j-x_i)$ with the signed cross matrix $D_{20}$ of \eqref{eq:l20-cross-matrix}, for independent halves $x,x'$ with the law $\lambda_{F,p}$. In the expansion of $\E\mathsf K$ over the sets of cross edges, the sets that form a star (all their edges at one label, the centre) have total mean of modulus at most \[ m_\star=\frac{4\{(1-q)(q^2+2qr)+8q^2+33q^3+25q^4\}}{Z_4}. \] Hence, if the nonstar part $T_{\rm ns}$ of the soft kernel and the collision correction $T_{\rm coll}$ of \cref{subsec:middle-l20} have norms at most $N_{\rm ns}$ and $D_{\rm col}$, and $\eps_Z=N_{\rm ns}+D_{\rm col}+m_\star<1$, then the normalizer $Z_0=\E\mathsf K-\ip\one{T_{\rm coll}\one}$ of the L20 cut operator satisfies $|Z_0-1|\le\eps_Z$, and the normalizer centred at the half-law mean may use $R_Z=(1-\eps_Z)^{-1}\ge Z_0^{-1}$. \end{lemma} \begin{proof} \emph{The identities.} Expand $D_4$ over the partitions $\pi$ of the four labels, with the M\"obius coefficients of the partition lattice: \begin{equation}\label{eq:partition-coefficient} D_4=\sum_\pi\mu(\pi)\,\one_\pi,\qquad \mu(\pi)=\prod_{C\in\pi}(-1)^{|C|-1}(|C|-1)!\,, \end{equation} where $\one_\pi$ is the indicator that $x$ is constant on every block of $\pi$; expand $P_{\rm adm}$ into its $16$ products over the sets of cross pairs and $\mathcal W_k$ into its $k$-sets $A$ with the signs $s_A$. Identifying the labels of each block of $\pi$ leaves $|\pi|$ independent uniform labels and costs the factor $q^{4-|\pi|}$. After division by $p$, each of the $16\cdot5\cdot15=1200$ terms is therefore $s_A\mu(\pi)q^{4-|\pi|}$ times the moment of the oriented graph on the merged labels and the summation label $z$, with the chosen cross pairs and the edges from $z$ to the labels of $A$; edges reversed by the identification contribute their signs $\chi(-1)=-1$, and a loop makes the term zero. Each moment is reduced by the rules (G1)--(G4) of the proof of \cref{lem:record:weighted-moment}, which are exact for every prime $p\equiv3 \pmod4$. The reduced terms with $|A|=3$ cancel, and those with $|A|=4$ add up to $M_{G_5}+8q^2-33q^3+25q^4$; the bookkeeping of the $1200$ reductions is the finite symbolic computation of \cref{cert:l20-star-mean}. \emph{The star means.} Under $\lambda_F\otimes\lambda_F$ the centre $z$ of a star is a coordinate of one half, uniform on $\Fp$ and independent of the other half, which carries the leaves; the leaves are distinct labels. By the orientation of the factors, a star centred in the first half has the sign $(-1)^{\#\text{leaves}}$ in addition to the product of its entries of $D_{20}$. A one-leaf star has mean zero, as $\E_z\chi(z-y)=0$. A two-leaf star has mean $-q$ times the product of its two entries, because $\E_z\chi(z-y)\chi(z-y')=-q$ for $y\ne y'$ (\cref{lem:paley-triple}(b)). The rows of $D_{20}$, and also its columns, are of two kinds (\eqref{eq:l20-cross-matrix}): four have two nonzero entries, of equal sign, at the labels $b_0,b_1$ of the other half; two have four nonzero entries, at the labels $a_0,a_1,c_0,c_1$ of the other half, with the signs $\pm(-1,-1,1,1)$. The products of the entries over the two-element subsets of the support therefore sum, over the rows and over the columns, to $4\cdot1+2\cdot(-2)=0$, and the two-leaf means cancel. Stars with three or four leaves occur only at the four centres of the second kind, two on each side, and their leaves are the four labels $(a_0,a_1,c_0,c_1)$ of the other half. Under $\lambda_F$ these labels are uniform on the admissible ordered quadruples (distinct, with $a_i\to c_j$), since each admissible quadruple has exactly $(p-4)(p-5)$ completions by $(b_0,b_1)$; for independent uniform labels $P_{\rm adm}D_4$ is $16$ times the indicator of the admissible event, which has probability $p(p-1)k_p(k_p-1)/p^4=Z_4/16$. Hence $\E_{\lambda_F}[f]=\E[P_{\rm adm}D_4f]/Z_4$ for every function $f$ of the four labels. At such a centre the three-leaf stars together have the mean $\pm\E_{\lambda_F}[\mathcal W_3]/p$, which is zero by \eqref{eq:l20-star-identities}, and the four-leaf star, whose sign product is $+1$, has the mean $\E_{\lambda_F}[\mathcal W_4]/p =(M_{G_5}+8q^2-33q^3+25q^4)/Z_4$. By \eqref{eq:record:modular-moment}, $|M_{G_5}|\le(1-q)(q^2+2qr)$, so the four centres give at most $m_\star$. The empty set of edges gives one and the nonstar sets give $\ip\one{T_{\rm ns}\one}$, of modulus at most $N_{\rm ns}$; the collision correction $\ip\one{T_{\rm coll}\one}$ has modulus at most $D_{\rm col}$. So $|Z_0-1|\le m_\star+N_{\rm ns}+D_{\rm col}=\eps_Z$, and $Z_0\ge1-\eps_Z>0$. \end{proof} With $q=r^2$, $m_\star/r^2$ is a positive increasing function of $r$ for $00$ as well, since $\Delta_{\max}<\upsilon_\times$. \begin{enumerate}[label=(\roman*)] \item The half law $\nu_{\mathrm L,p}$ of the root at one prime satisfies $R_p^{-1}\le d\nu_{\mathrm L,p}/d\lambda_{F,p}\le R_p$; moreover the supremum of this density is at most $R_p$ times its infimum. \item $\chi_p:=\chi^2(\nu_{\mathrm L,p}\,\|\,\lambda_{F,p})\le \min\bigl((R_p-1)^2/R_p,\,D_{\rm full}^2/L_{\rm low}^2\bigr)$. \item Let $\Blk$ be a middle block whose primes are at least $X$, with $\log q_\Blk\le L$, and let $n\ge\lfloor L/\log X\rfloor$ be an integer. Then hypothesis (A) holds with $M_\Blk=\prod_{p\in\Blk}R_p\le\bar R(X)^n$, and \[ \chi^2(\nu_{\mathrm L,\Blk}\,\|\,\lambda_{F,\Blk})=\prod_{p\in\Blk}(1+\chi_p)-1 \le\bigl(1+\bar\chi(X)\bigr)^n-1, \] where $\bar R(X)$ and $\bar\chi(X)$ are the right sides of (i) and (ii) evaluated at $q=1/X$ and any fixed $r\ge X^{-1/2}$ for which the two lower factors are positive (the notation suppresses this $r$; \eqref{eq:variance:pieces} takes $r=1/\lfloor\sqrt X\rfloor$). \item \emph{Positive roots.} Let $\Blk$ be a middle block of one of the pieces starting at $X\in\{2^{30},2^{31},2^{32},2^{34},2^{36},2^{40},2^{45}\}$, whose root is the positive root $\Gamma_{\Blk,\ulaw}$ of \cref{def:positive-root}, with $\log q_\Blk\le L$ and $n\ge\lfloor L/\log X\rfloor$, and let $R_\ulaw(X)$ and $d_\ulaw(X)^2$ be the range ratio and the variance bound of the half marginal of $\Gamma_{p,\ulaw}$ at the chamber cut $\vartheta_0$ given by \cref{prop:root-chamber,imp:env:coherent-parameter,imp:env:coherent-single-pin} at the endpoint $X$, whose gates hold there (\cref{cert:positive-root-caps}). Then hypothesis (A) holds for the half law $\nu_{\mathrm L,\Blk}$ of $\Gamma_{\Blk,\ulaw}$ with $M_\Blk\le R_\ulaw(X)^n$, and \[ \chi^2(\nu_{\mathrm L,\Blk}\,\|\,\lambda_{F,\Blk})\le \bigl(1+d_\ulaw(X)^2\bigr)^n-1 . \] \end{enumerate} \end{lemma} \begin{proof} Work at $\vartheta_0$, with half $H_0=\{0,1,2\}$; the half law does not depend on the chamber. A half configuration is $y=(y_{u,\ell})_{u\in\{0,1,2\},\,\ell\in \{0,1\}}$, six distinct labels with $y_{0,\ell}\to y_{2,\ell'}$. It completes to a root configuration by labels $y_{u,\ell}$, $u\in\{3,4,5\}$, subject to $y_{2,\ell}\to y_{4,\ell'}\to y_{0,\ell''}$ (even triangle) and $y_{1,\ell}\to y_{5,\ell'}\to y_{3,\ell''}\to y_{1,\ell'''}$ (odd triangle), for all layer indices, all twelve labels distinct. \emph{Odd component.} Fix $(y_{1,0},y_{1,1})$ and let $\mathcal O$ be the set of $(y_{5,0},y_{5,1},y_{3,0},y_{3,1})$ satisfying the odd constraints with the six odd labels distinct, and $\mathcal Z=|\mathcal O|$. The labels $y_{5,\ell}$ are an ordered distinct pair of common successors of $y_{1,0},y_{1,1}$ ($k_p(k_p-1)$ choices), and given them the labels $y_{3,\ell}$ are an ordered distinct pair in the signed neighbourhood of $(y_{5,0},y_{5,1},y_{1,0},y_{1,1})$ with the signs $(1,1,-1,-1)$. By \cref{lem:record:signed-nbhd}, $\mathcal Z\ge k_p(k_p-1)(p/16)^2(1-\upsilon_-)(1-\upsilon_--16q)$. The number of elements of $\mathcal O$ with a prescribed value of $y_{5,0}$ is at most $(k_p-1)(p/16)^2(1+\upsilon_+)^2$; the same bound holds for $y_{5,1}$, and, choosing $y_{3,0},y_{3,1}$ first as common predecessors of $y_{1,0},y_{1,1}$, for $y_{3,0}$ and $y_{3,1}$. So under the uniform law on $\mathcal O$ each of the four free odd labels takes any given value with probability at most $\mathfrak a_p$, since $1/k_p=4q/(1-3q)$. Finally $\mathcal Z$ does not depend on $(y_{1,0},y_{1,1})$: the maps $z\mapsto cz+c'$ with $\chi(c)=1$ preserve all the constraints and act transitively on the ordered distinct pairs with a fixed value of $\chi(y_{1,1}-y_{1,0})$; $\mathcal O$ depends only on the set $\{y_{1,0},y_{1,1}\}$, because all four lifts of each edge are present; and the two orders of the pair have opposite values of $\chi(y_{1,1}-y_{1,0})$, since $\chi(-1)=-1$. \emph{Even component.} Given $y$, the pair $(y_{4,0},y_{4,1})$ is an ordered distinct pair in the signed neighbourhood of $(y_{0,0},y_{0,1},y_{2,0},y_{2,1})$ with the signs $(-1,-1,1,1)$, avoiding $y_{1,0},y_{1,1}$. By \cref{lem:record:signed-nbhd} the number of such pairs lies between $(p/16)^2(1-\upsilon_\times)(1-\upsilon_\times-16q)$ and $(p/16)^2(1+\upsilon_+)^2$. For each such pair, the odd completions that avoid the six even labels form a subset of $\mathcal O$ of relative size between $1-24\mathfrak a_p$ and $1$, by the union bound over four free odd labels and six forbidden values. Hence the number $\mathfrak N(y)$ of completions of $y$ satisfies \begin{equation}\label{eq:record:root-count} (1-\upsilon_\times)(1-\upsilon_\times-16q)(1-24\mathfrak a_p) \le\frac{\mathfrak N(y)}{\mathcal Z(p/16)^2}\le(1+\upsilon_+)^2 . \end{equation} (i) The density of $\nu_{\mathrm L,p}$ with respect to the uniform law $\lambda_{F,p}$ on the half configurations is $\mathfrak N(y)/ \E_{\lambda_F}\mathfrak N$. By \eqref{eq:record:root-count} the values of $\mathfrak N$ lie in an interval $[c,R_pc]$, $c>0$ ($\mathcal Z$ cancels), and so does their mean; hence the supremum of the density is at most $R_p$ times its infimum, and the density lies in $[R_p^{-1},R_p]$. (ii) A density $g$ with $\E g=1$ and values in $[R^{-1},R]$ satisfies $\E(g-R^{-1})(R-g)\ge0$, that is, $\E g^2\le R+R^{-1}-1$; this is the first bound. For the second, under $\lambda_{F,p}$ the four labels $x=(y_{0,0},y_{0,1},y_{2,0},y_{2,1})$ are uniform on the \emph{admissible} ordered quadruples (distinct, with $y_{0,\ell}\to y_{2,\ell'}$), since each has exactly $(p-4)(p-5)$ choices of $(y_{1,0},y_{1,1})$; for independent uniform labels the admissible event has probability $p(p-1)k_p(k_p-1)/p^4=Z_4/16$. For admissible $x$ the soft count with the signs $(-1,-1,1,1)$ equals $p+2+\mathcal W$: the singleton sums vanish, each quadratic sum is $-1$ by \eqref{eq:two-root}, and $\sum_{i0$, and $\mathcal F(C,h,M,\chi)=0$ if $l\le0$. As $l\le1\le C$ always and $Y[\Pi_X]\ge0$, the lemma gives $Y[\Pi_X]\ge(\mathcal F(C,h_X,M_X,\chi_X)-o(1))Y$ under its other hypotheses. In the construction the cap is a product of piece caps: if every block of the piece $i$ has $\log q_\Blk\le L_i$ and $a_*\ge a$, then every block of $X$ lying in the piece $i$ has $q_\Blk^{2a}\le C_i:=e^{2a_*L_i}$, so $C_X$ is at most the product $\prod_{\Blk\in X}C_{i(\Blk)}$ of the caps of the pieces of its blocks (\cref{lem:piece-caps}), and the lemma is applied with this product as $C$; the construction takes $a_*=a$ and the numbers $L_i$ of \cref{lem:piece-caps}. \begin{remark}[The three branches]\label{rem:variance:branches} The second expression in $l_0$ never exceeds the third: the smaller root $\bar\eta_*$ satisfies $l-\bar\eta_*=(\chi_X\bar\eta_*(C-\bar\eta_*))^{1/2}\le \frac C2\sqrt{\chi_X}$. It is kept because the certificate evaluates all three expressions, and zero (\cref{cert:variance:fresh}); the certificate also checks the condition $0\le l\le C/2$, whereas the lemma needs only $l\le C$ (at the final caps $l\le110^7$. The bounded-variance expressions therefore provide the useful restoration on these pieces; the same exact formulas are reevaluated for their own marginals in \cref{cert:variance:fresh}. \end{remark} \subsection{Centred norms at the reserved cut}\label{subsec:variance:centred} The last step converts a lower bound for the energy of a product of eligible records into one for the product of its actual half marginals, by the centred interpolation \ref{it:record:P3} at $\iota$. It needs, for each record, the norm on the mean-zero space of its own Markov operator at $\iota$, in its own actual marginal space: for the fold records the centred norm $\kappa_F(q,r)$ of \cref{lem:record:old-f-marginal}(c), an admissible function of $(q,r)$ that the certificate evaluates at the piece start, and for the matching records the norm $3/(b-3)$ of the disjoint-triple operator (\cref{lem:record:paired-e-bridge}(b) below). For a product of records the centred norm is the largest of the prime centred norms, not their sum (\cref{lem:sector}(c), \cref{lem:record:old-f-marginal}(d)), because each prime operator fixes the constants of its own actual marginal on both sides; we write $\kappa_F(\Blk)$ for the largest value of $\kappa_F(1/p,p^{-1/2})$ at the primes $p$ of $\Blk$. Inside $\kappa_F$, the kernel of two disjoint cross edges whose four endpoints do not span a complete rectangle has norm at most $q$ for independent uniform labels, which is case (a) of \cref{lem:matching:kernel}, and \cref{lem:record:projection} transfers the bound to the actual marginal (\cref{lem:old-f-law}(b)). \subsection{Variance savings for \texorpdfstring{$E_0,E_1$}{E\_0,E\_1} via polarization}\label{subsec:variance:matching} The records $E_0,E_1$ are matchings, not folds, and no chamber diagonal is a matching record. Their energies are reached from those of the two fold records by a polarization at the chamber cut $\vartheta_0$. For a middle block $\Blk$ let $G_{e,\Blk}$ and $G_{o,\Blk}$ be the images of $\lambda_E$ under the merges $G_e=(1,0,0,0,0,1)$ and $G_o=(0,0,1,1,0,0)$ of \cref{def:patterns} (two objects used); they are positive normalized laws with uniform one-slot marginals, diagonal at $\vartheta_0$. By the corner table of \cref{lem:record:fold-identification}(f) (\cref{tab:corner}), at $\vartheta_0$ the cut matrices of $\Pi_{E_0,\Blk}$ and $G_{e,\Blk}$ live on the corner $\mathcal U$ of the plus-half configurations $(\beta,y,y)$, those of $\Pi_{E_1,\Blk}$ and $G_{o,\Blk}$ on the corner $\mathcal V$ of the configurations $(y,y,\beta)$, and $\Pi_{F_1,\Blk}$, $\Pi_{F_2,\Blk}$ connect the two corners; here $\beta$ is the label pair of the object that is not repeated. Let $f_2,h_2$ be the two-layer row coefficients of the piece of $\Blk$ (\cref{lem:front12:reference}(i); the index $2$ counts the layers), put $\varepsilon_\Blk=(f_2+h_2)r_\Blk$, and $\kappa_E(\Blk)=3/(b_\Blk-3)$. For a finite set $X$ of middle blocks write $E_{\mathbf s}=\bigotimes_{\Blk\in X}\Pi_{E_{s_\Blk},\Blk}$, $\mathbf s\in\{0,1\}^X$, for the $2^{|X|}$ \emph{matching embeddings}, $J_{\mathbf s}=\bigotimes_\Blk J_{E_{s_\Blk},\Blk}$ for their products of actual half marginals, and $E^X_0$, $E^X_1$ for the two \emph{aligned} embeddings, with $E_0$, respectively $E_1$, on every block. \begin{lemma}[Paired $E$ bridge]\label{lem:record:paired-e-bridge} Let $\Blk$ be a middle block. \begin{enumerate}[label=(\alph*)] \item As cut matrices at $\vartheta_0$ of laws on the labels of $\Blk$, \[ \Pi_{E_0,\Blk}+\Pi_{E_1,\Blk}+\varepsilon_\Blk(G_{e,\Blk}+G_{o,\Blk}) \succeq_{\vartheta_0}\Pi_{F_1,\Blk}+\Pi_{F_2,\Blk}. \] \item At $\iota$ the Markov operator $T_E$ of $\Pi_{E_s,\Blk}$ on $L^2(m_{E_s,\Blk})$ is self-adjoint and $\|T_E-\Jproj\|\le\kappa_E(\Blk)$. More generally, every matching embedding $E_{\mathbf s}$ of a finite set $X$ of middle blocks is symmetric at $\iota$, and its Markov operator on $L^2$ of its actual half marginal has centred norm at most $\max_{\Blk\in X}\kappa_E(\Blk)$. \end{enumerate} \end{lemma} \begin{proof} (a) As in the proof of \cref{lem:front12:reference}(iii), the two-layer laws of $\Blk$ form a five-type datum (\cref{def:five-type-datum}) on the label pairs of one object: the middle law $\nu$ and the conditional references $\nu^\xi$ of \cref{lem:front12:reference}(i), the matching law $\lambda_E$, its two-object marginal, the fold law $\lambda_F$ and the root. By \cref{lem:front12:reference}(i) the middle object has the law $\nu$ under $\lambda_F$ as well as under $\lambda_E$ (this uses $p\equiv3\pmod4$), and $\|T^\xi_{\rm F}-\Jproj\|\le f_2r_\Blk$, $\|T^\xi_{\rm E}-\Jproj\|\le h_2r_\Blk$ on $L^2(\nu^\xi)$ for every $\xi$. The components of this datum at $\vartheta_0$ are $\Pi_{F_j,\Blk}$, $\Pi_{E_s,\Blk}$, $G_{e,\Blk}$ and $G_{o,\Blk}$, read on the slot array through the first coordinate. So (a) is \cref{lem:tr:polarization}(a) with $e_{\rm F}=f_2r_\Blk$, $e_{\rm E}=h_2r_\Blk$ and $\varepsilon=\varepsilon_\Blk$: the form of the difference of the two sides is at least the average over $\xi$ of $(u_\xi-v_\xi)^2\ge0$, with $u_\xi,v_\xi$ the conditional means of the two corner functions. As $\nu^\xi$ gives no mass to $\xi$, the datum also satisfies the hypothesis of \cref{lem:tr:polarization}(b). (b) By \cref{lem:record:fold-identification}(d), $\Pi_{E_s,\Blk}$ is symmetric at $\iota$ and its actual half marginal is uniform on ordered triples of distinct labels; given the layer-zero triple, the layer-one triple is uniform among those disjoint from it. So $T_E$ is the tensor product over the primes of $\Blk$ of the disjoint-triple operators of \cref{sec:frontier:empty-triple-negative}, which are self-adjoint, and part (c) of that lemma gives $\|T_E-\Jproj\|\le3/(b_\Blk-3)$. An embedding $E_{\mathbf s}$ is a product of such records, hence symmetric at $\iota$, and its operator is the tensor product of the operators of its blocks, each fixing the constants of its actual marginal on both sides; so \ref{it:record:P4} bounds its centred norm by the largest block value (\cref{lem:sector}(c)). \end{proof} \begin{lemma}[Matching selections]\label{lem:record:paired-e-joint} Let $X$ be a set of $k\ge1$ middle blocks, with $\varepsilon_\Blk$, $G_{e,\Blk}$, $G_{o,\Blk}$ as above, $G_{0,\Blk}=G_{e,\Blk}$, $G_{1,\Blk}=G_{o,\Blk}$ and $G_\Blk=G_{e,\Blk}+G_{o,\Blk}$. \begin{enumerate}[label=(\alph*)] \item At the chamber cut $\vartheta_0$, \[ \bigotimes_{\Blk\in X}\bigl(\Pi_{E_0,\Blk}+\varepsilon_\Blk G_{e,\Blk}\bigr) +\bigotimes_{\Blk\in X}\bigl(\Pi_{E_1,\Blk}+\varepsilon_\Blk G_{o,\Blk}\bigr) \succeq_{\vartheta_0}\bigotimes_{\Blk\in X}\Pi_{F_1,\Blk} +\bigotimes_{\Blk\in X}\Pi_{F_2,\Blk}, \] and consequently $\bigotimes_\Blk(\Pi_{E_0,\Blk}+\Pi_{E_1,\Blk}+\varepsilon_\Blk G_\Blk) \succeq_{\vartheta_0}\bigotimes_\Blk\Pi_{F_1,\Blk}+\bigotimes_\Blk\Pi_{F_2,\Blk}$. \item Let $C\ge C_X$, $\varepsilon_X\ge\prod_\Blk(1+\varepsilon_\Blk)-1$, and suppose $Y[\bigotimes_\Blk\Pi_{F_j,\Blk}]\ge(l_0-o(1))Y$ for $j=1$ and $j=2$. Then \begin{align*} \tfrac12\bigl(Y[E^X_0]+Y[E^X_1]\bigr)&\ge(l_0-C\varepsilon_X-o(1))Y,\\ 2^{-k}\textstyle\sum_{\mathbf s}Y[E_{\mathbf s}] &\ge(2^{1-k}l_0-C\varepsilon_X-o(1))Y. \end{align*} \item Under the hypotheses of (b), let $m^X_s$ be the actual half marginal of $E^X_s$ at $\iota$. Then \[ Y[\operatorname{Diag}_\iota(m^X_0)]+Y[\operatorname{Diag}_\iota(m^X_1)] \ge2\bigl([l_0-C\varepsilon_X]_+-o(1)\bigr)Y . \] \end{enumerate} By \cref{lem:record:restoration} one may take for $l_0$ the restoration bound of $X$: the same $h_X$, $M_X$, $\chi_X$ serve $j=1$ and $j=2$, because the half law of the root does not depend on the chamber (also for the positive roots, \cref{lem:record:root-marginal}(iv)). No lower bound is asserted for an individual matching embedding, nor for the diagonal of an individual aligned embedding. \end{lemma} \begin{proof} (a) Both orders are \cref{lem:tr:polarization}(c), applied to the two-layer five-type data of the blocks of $X$, which satisfy the hypotheses of \cref{lem:tr:polarization}(b) with the constants $\varepsilon_\Blk$ (proof of \cref{lem:record:paired-e-bridge}(a)). The first is the compression to the two aligned corners of the tensor product of the one-block brackets, the sign of the fold part being reversed on the corner $\mathcal V$; the second adds the $2^k-2$ nonaligned corner products $\bigotimes_\Blk(\Pi_{E_{s_\Blk},\Blk}+\varepsilon_\Blk G_{s_\Blk,\Blk})$, which are tensor products of positive semidefinite diagonal blocks of these brackets. The order is not obtained by tensoring a one-sided order with an indefinite factor. (b) Apply \ref{it:record:E2} at $\vartheta_0$, with $\mu$ outside, to the two orders of (a). In the first order, expanding $\bigotimes_\Blk(\Pi_{E_s,\Blk}+\varepsilon_\Blk G_{s,\Blk})$ gives $E^X_s$ and products that contain at least one merge law; these are positive measures with uniform one-slot marginals of total mass $\prod_\Blk(1+\varepsilon_\Blk)-1$, so by \ref{it:record:E1} \[ Y[E^X_0]+Y[E^X_1]\ge2(l_0-o(1))Y-2C\Bigl(\prod_\Blk(1+\varepsilon_\Blk)-1\Bigr)Y. \] In the second order the merge products have total mass $\prod_\Blk(2+2\varepsilon_\Blk)-2^k$, so $\sum_{\mathbf s}Y[E_{\mathbf s}]\ge2(l_0-o(1))Y-2^kC(\prod_\Blk(1+\varepsilon_\Blk) -1)Y$. Divide by $2$, respectively $2^k$. (c) By \cref{lem:record:paired-e-bridge}(b), $E^X_s$ is a positive law symmetric at $\iota$, a probability coupling of two copies of $m^X_s$; so the contraction \ref{it:record:P1}, applied to the whole product, gives $Y[E^X_s]\le Y[\operatorname{Diag}_\iota(m^X_s)]$, and no one-sided order is tensored with an indefinite factor. Adding the two bounds and using the first bound of (b) gives the claim with $l_0-C\varepsilon_X$ in place of its positive part; and $Y[\operatorname{Diag}_\iota(m^X_s)]\ge0$ by \ref{it:record:E3} and \ref{it:record:E2}. \end{proof} The factor $2^{1-k}$ in the second bound of (b) is a genuine loss: only the two aligned corners carry the restoration. The first bound has no such loss, and its merge correction is $2\varepsilon_X$ against $2^k\varepsilon_X$ for the second. For two blocks, $l_0-C\varepsilon_X$ exceeds twice $l_0/2-C\varepsilon_X$, which is why the aligned gain is at least twice the four-embedding gain (\cref{cor:var-classes}), and why the construction credits only the aligned matching classes. Part (c) is the diagonal-mean coupon $2[l_0-C\varepsilon_X]_+$ of the matching diagonals of the mean credit (\cref{prop:record:mean-credit}), for any number of blocks. \subsection{The saving \texorpdfstring{$g$}{g}: product energy at least \texorpdfstring{$gC_XY$}{gC\_XY}}\label{subsec:variance:gain} A \emph{selection} of the record expansion (\cref{lem:record:record-expansion}) puts on each block of a finite set $X$ one changed record and one parity, symmetric or skew, with an even number of skew parities; $I_\omega$ is its term in $Y_\nu-Y_\lambda$ and $\pi_\omega$ its price, the product over $\Blk\in X$ of the prices of its records with their parities. For a record assignment $\boldsymbol\phi=(\phi_\Blk)_{\Blk\in X}$ of eligible records put $\Pi_{\boldsymbol\phi}=\bigotimes_\Blk\Pi_{\phi_\Blk,\Blk}$, $m_{\boldsymbol\phi}=\bigotimes_\Blk m_{\phi_\Blk,\Blk}$ and $J_{\boldsymbol\phi}=\bigotimes_\Blk J_{\phi_\Blk,\Blk}$. \begin{lemma}[Variance gain]\label{lem:var-gain} Let $X$ be a nonempty finite set of middle blocks, with a parity for each $\Blk\in X$, an even number of them skew. Let $\mathcal R$ be a nonempty finite set of record assignments $\boldsymbol\phi$ of eligible records, and let $\omega_{\boldsymbol\phi}$ be the selection with the records $\phi_\Blk$ and the fixed parities. Suppose that, for every $\Blk$, the price of $\phi_\Blk$ with the parity of $\Blk$ is the same for all $\boldsymbol\phi\in\mathcal R$. Let $C\ge C_X$, $l_0\in\R$ and $0\le\kappa<1$, and assume: \begin{enumerate}[label=(\textup{\Roman*})] \item[\textup{(Res)}] $|\mathcal R|^{-1}\sum_{\boldsymbol\phi\in\mathcal R} Y[\Pi_{\boldsymbol\phi}]\ge(l_0-o(1))Y$; \item[\textup{(Cen)}] for every $\boldsymbol\phi\in\mathcal R$, $\Pi_{\boldsymbol\phi}$ is symmetric at $\iota$, and its Markov operator $T_{\boldsymbol\phi}$ on $L^2(m_{\boldsymbol\phi})$ satisfies $\|T_{\boldsymbol\phi}-\Jproj\|\le\kappa$. \end{enumerate} Put $\bar l=(l_0/C-\kappa)/(1-\kappa)$ and $g=[\bar l-R_{\rm err}]_+$. Then: \begin{enumerate}[label=(\alph*)] \item $|\mathcal R|^{-1}\sum_{\boldsymbol\phi}Y[J_{\boldsymbol\phi}]\ge (\bar l-o(1))C_XY$; \item $\sum_{\boldsymbol\phi}|I_{\omega_{\boldsymbol\phi}}|\le(B-g+o(1)) \sum_{\boldsymbol\phi}\pi_{\omega_{\boldsymbol\phi}}Y$; \item if $l_0\le C$, then $0\le g\le1\le B$, so the selections $\omega_{\boldsymbol\phi}$, $\boldsymbol\phi\in\mathcal R$, form a class of cost $B-g$ in the sense of (CP5). \end{enumerate} Any upper bound for $R_{\rm err}$ may replace it in $g$. \end{lemma} \begin{proof} (a) Fix $\boldsymbol\phi$. By (Cen), the centred interpolation \ref{it:record:P3} at $\iota$, with $\mu$ outside and $\kappa_0=\kappa$, gives $Y[\Pi_{\boldsymbol\phi}]\le(1-\kappa)Y[J_{\boldsymbol\phi}]+ \kappa Y[\operatorname{Diag}_\iota(m_{\boldsymbol\phi})]$, as $J_{\boldsymbol\phi}=J_\iota(m_{\boldsymbol\phi})$; and \ref{it:record:E1} bounds the last energy by $(1+o(1))C_XY$. Averaging over $\mathcal R$ and using (Res), $(1-\kappa)|\mathcal R|^{-1}\sum_{\boldsymbol\phi}Y[J_{\boldsymbol\phi}]\ge (l_0-\kappa C_X-o(1))Y$. If $\bar l\le0$, (a) holds because $Y[J_{\boldsymbol\phi}]\ge0$ by \ref{it:record:E2}, the cut operator of $J_{\boldsymbol\phi}$ being a projection. If $\bar l>0$, then $l_0>0$, so $l_0\ge l_0C_X/C$ and $l_0-\kappa C_X\ge(1-\kappa)\bar lC_X$. (b) For $\boldsymbol\phi\in\mathcal R$ and $\Blk\in X$, the change of $\phi_\Blk$ with the parity of $\Blk$ has, relative to $m_{\phi_\Blk,\Blk}$, a cut operator $D_\Blk$ at $\iota$ that is self-adjoint or skew-adjoint, annihilates the constants on both sides by \eqref{eq:record:zero-marginal}, and has norm at most the coefficient $\tilde\pi_\Blk$ of its norm envelope (\cref{def:record:comparison-law}); by hypothesis $\tilde\pi_\Blk$ does not depend on $\boldsymbol\phi$, and $\pi_{\omega_{\boldsymbol\phi}}=\prod_\Blk\tilde\pi_\Blk\,C_X$. By \cref{lem:record:variance-interface}(i),(ii), applied with these $D_\Blk$, \[ |I_{\omega_{\boldsymbol\phi}}|\le\prod_\Blk\tilde\pi_\Blk\bigl( Y^{\Nbr}[\operatorname{Diag}_\iota(m_{\boldsymbol\phi})]- Y^{\Nbr}[J_{\boldsymbol\phi}]\bigr) \le\prod_\Blk\tilde\pi_\Blk\bigl((B+R_{\rm err}+o(1))C_XY -Y[J_{\boldsymbol\phi}]\bigr). \] Summing over $\mathcal R$ and using (a) gives $\sum|I_{\omega_{\boldsymbol\phi}}|\le(B-(\bar l-R_{\rm err})+o(1)) \sum\pi_{\omega_{\boldsymbol\phi}}Y$. If $\bar l-R_{\rm err}\le0$ use instead $|I_{\omega_{\boldsymbol\phi}}|\le\prod_\Blk\tilde\pi_\Blk\, Y^{\Nbr}[\operatorname{Diag}_\iota(m_{\boldsymbol\phi})]\le(B+o(1)) \pi_{\omega_{\boldsymbol\phi}}Y$, valid because $Y^{\Nbr}[J_{\boldsymbol\phi}]\ge0$ by \ref{it:record:E2}. A larger $R_{\rm err}$ only lowers $g$. (c) If $l_0\le C$ then $\bar l\le1$, so $g\le1$; and $B=e^{U_0}+R_{\rm err}\ge1$. \end{proof} The lemma uses the parities only through the evenness of the number of skew factors. It applies to two symmetric parities as well as to two skew ones, and selections with different parities, records or blocks are different monomials of the record expansion. \begin{corollary}[The eligible variance classes]\label{cor:var-classes} Let $X$ be a set of $k\ge1$ middle blocks with fixed parities as in \cref{lem:var-gain}, and let $C\ge C_X$. Let $h_X$, $M_X$, $\chi_X$ be as in \cref{lem:record:restoration}, with $0R_*$, then $\tilde b>0$ and $C_m\tilde b\ge C_X\tilde b$, so summing over $s$, \[ |I_{\omega_0}|+|I_{\omega_1}|\le\bigl(B-(\tilde b-R_{\rm err})+o(1)\bigr) (\pi_{\omega_0}+\pi_{\omega_1})Y\le\bigl(B-g_E(m)+o(1)\bigr)(\pi_{\omega_0} +\pi_{\omega_1})Y . \] If $\tilde b\le R_*$, then $g_E(m)=0$, and $|I_{\omega_s}|\le\gamma Y^{\Nbr}[ \operatorname{Diag}_\iota(m^X_s)]\le(B+o(1))\pi_{\omega_s}Y$ as in the proof of \cref{lem:var-gain}(b). Finally $0\le g_E(m)\le1\le B$. (b) The exterior contains no fold diagonal, and (b) is \cref{cor:var-classes}(i) with \cref{lem:var-gain}(c), $C=C_m$ and $\bar l_F=b_F(m)$. \end{proof} The background terms lower one selected variance; they are not separate selected records, and they carry no price of their own. All of them are terms of the one expansion of $\Nbrz$ outside the selected blocks, so the exterior error $R_{\rm err}$ is paid once, and the positive part is taken only after it is subtracted. On the two aligned assignments the background blocks carry the matching diagonal of the same type as the selected records, and the restoration of the union keeps both fold products of the aligned bridge; no assertion is made for a crossed matching assignment. Pooling is restricted to the pieces from $2^{31}$ because a uniform bound using the maxima over all pieces would lose the term; over those later pieces the maxima are the pool data with which the pooled term $P_E(m)$ of \eqref{eq:variance:background-gain} is formed, and that term is included at the certified piece values of \cref{cert:variance:fresh} when $b_E(m)\ge R_*$. \subsection{Assembly: the total saving \texorpdfstring{$D_{\rm var}$}{D\_var}}\label{subsec:variance:final} The final construction uses the credits of degrees one to four. They are evaluated once per middle piece and per multiset of pieces, at the piece starts. \paragraph{Piece values.} Let $[X_i,Y_i)$, $i=1,\dots,33$, be the middle pieces (\cref{def:record:exact-blocks}, \cref{tab:record:middle-pieces}). Every block of the piece $i$ has least prime at least $X_i$ and at most $\lfloor L/\log X_i\rfloor\le n_i$ primes (\cref{lem:record:local-domain}), where $L=570$ and $n_i=\lfloor L/\log_-X_i\rfloor$ with a rational lower bound $\log_-X_i\le\log X_i$; and every coefficient below is a nondecreasing function of $(q,r)$ (\cref{lem:majorant}), evaluated at $q=1/X_i$ and $r=1/\lfloor\sqrt{X_i}\rfloor\ge X_i^{-1/2}$, except that on the seven pieces with positive roots $R_\ulaw$ and $d_\ulaw$ are the endpoint bounds of \cref{cert:positive-root-caps}, valid at every larger prime. The \emph{piece values} are upper bounds \begin{equation}\label{eq:variance:pieces} \begin{gathered} h_i\ge h(X_i),\qquad M_i\ge\bar R(X_i)^{n_i},\qquad \chi_i\ge\bigl(1+\bar\chi(X_i)\bigr)^{n_i}-1\qquad(i\le26),\\ M_i\ge R_\ulaw(X_i)^{n_i},\qquad \chi_i\ge\bigl(1+d_\ulaw(X_i)^2\bigr)^{n_i}-1\qquad(27\le i\le33),\\ k_{F,i}\ge\kappa_F\bigl(1/X_i,1/\lfloor\sqrt{X_i}\rfloor\bigr),\qquad k_{E,i}=\frac3{X_i-3},\qquad \varepsilon_i\ge\frac{f_2+h_2}{\lfloor\sqrt{X_i}\rfloor},\qquad H_i=\Bigl(1+\frac2{X_i-4}\Bigr)^{n_i}, \end{gathered} \end{equation} where $h(X_i)$ is \eqref{eq:record:nonroot-mass} with the completion weights of the piece (\cref{sec:middle-frame}), $\bar R$ and $\bar\chi$ are those of \cref{lem:record:root-marginal}(iii), $R_\ulaw$ and $d_\ulaw$ those of \cref{lem:record:root-marginal}(iv) on the seven pieces with positive roots, $\kappa_F$ is the centred norm of \cref{lem:record:old-f-marginal}(c), $f_2,h_2$ are the two-layer row coefficients of the piece, and $H_i$ is the density factor of the actual fold marginal used by the mean savings (\cref{lem:record:companion-energy}). By \cref{lem:record:root-marginal}, \cref{lem:record:old-f-marginal}, \cref{lem:record:paired-e-bridge}(b) and monotonicity, every block $\Blk$ of the piece $i$ has $h_\Blk\le h_i$, $M_\Blk\le M_i$, $\chi^2(\nu_{\mathrm L,\Blk}\|\lambda_{F,\Blk})\le\chi_i$, $\kappa_F(\Blk)\le k_{F,i}$, $\kappa_E(\Blk)\le k_{E,i}$ and $\varepsilon_\Blk\le\varepsilon_i$. Let $\Sigma_i$ be the certified lower bound of \cref{lem:record:lower-start-sums} for $\sum_{\Blk\subseteq[X_i,Y_i)}b_\Blk^{-1}$. The piece values do not depend on $a$; they are listed in \cref{tab:data:piece-values}. \paragraph{The cap.} Let $a_0=\PushAnchor$ be the evaluation exponent at which the middle prices are stored in \cref{tab:data:prices}, $t=e^{2(a-a_0)L}$ the repricing factor, and $C_i=e^{2aL_i}$ the piece caps of \cref{lem:piece-caps} at the anchor $a$, with the authenticated log caps $L_i\le L$ (the first is $L_1=9135105/16384$); every middle block of the piece $i$ has $q_\Blk^{2a}\le C_i$, and a set of blocks of pattern $m$ has $C_X\le C_m$. Together with the piece values, the caps and the numbers $\Sigma_i$ are piece data in the sense of \cref{subsec:variance:backgrounds}. Let $B_*\ge B$ and $R_*\ge R_{\rm err}$ be the certified upper bounds of \cref{def:closing-quantities}(2) at the exponent $a$ (\cref{cor:first-stage-repricing,cor:two-cut-series}). \paragraph{Fresh restorations and gains.} With these data, $\ell_m=\mathcal F(C_m,h_m,M_m,\chi_m)$ is formed for every multiset $m$ of pieces of size at most four, and on the pool of size at most six, the selected-only margins $b_F(m)$, $b_E(m)$ are those of \eqref{eq:variance:margins}, and the gains are \begin{equation}\label{eq:variance:fresh} g_F(m),\ g_E(m)\ \ \text{of \eqref{eq:variance:background-gain}}\ \ (|m|\le2), \qquad g^{\rm sel}_T(m)=\bigl[b_T(m)-R_*\bigr]_+\ \ (T\in\{F,E\},\ |m|\le4). \end{equation} Thus $g_F=g^{\rm sel}_F$, and $g_E(m)$ adds to $g^{\rm sel}_E(m)$ the positive backgrounds of degrees one and two and the late-pool terms of degrees three and four. The restorations depend only on the reference and the caps (\cref{rem:variance:independence}); they are also the restorations of the mean coupons (\cref{lem:record:companion-energy,prop:record:mean-credit}). \paragraph{Prices.} For the piece $i$ let $S_{F,i}$, $S_{E,i}$ (symmetric), $A_{F,i}$, $A_{E,i}$ (full skew) and $A^{\rm arm}_{F,i}$, $A^{\rm arm}_{E,i}$ (raw arm) be the prices of \cref{def:closing-quantities}(3) (\cref{tab:data:prices}): rounded upper bounds, at the exponent $a_0$, for the sums over the blocks of the piece of the prices of the two fold and of the two matching records, and of their raw-arm auxiliary prices, given by \cref{lem:middle-comparison-prices}; with the degree charges $\bar I_{d,i}$ of the piece, \begin{gather*} S_{F,i}=2w_{{\rm D},i}s_F(X_i)\bar I_{3,i},\qquad A_{F,i}=2w_{{\rm D},i}\ell_\tlaw(X_i)\bar I_{2,i}+2w_{{\rm D},i}a_F(X_i)\bar I_{3,i},\qquad A^{\rm arm}_{F,i}=2w_{{\rm D},i}\bar I_{2,i},\\ S_{E,i}=2w_{{\rm S},i}s_E(X_i)\bar I_{2,i},\qquad A_{E,i}=2w_{{\rm S},i}a_E(X_i)\bar I_{2,i},\qquad A^{\rm arm}_{E,i}=2w_{{\rm S},i}\bar I_{2,i}, \end{gather*} each rounded up as in \cref{def:closing-quantities}(3). Every middle block has $\log q_\Blk\le L$, so at the exponent $a$ these prices are at most $t$ times their values (\cref{lem:record:repricing}). By \cref{lem:record:record-expansion}(iii) each piece total is distributed over the blocks of the piece in proportion to their prices, the two records of one kind in a block receiving the same price (\cref{subsec:variance:eligible}); these per-block upper prices are the prices of the complete polynomial. \paragraph{The credit.} Put, with the double sums over ordered pairs of pieces and $g(i,j)$ the gain of the multiset $\{i,j\}$, \begin{equation}\label{eq:variance:dvar} \begin{split} D_{\rm var}={}&t\sum_i\bigl[g_F(i)S_{F,i}+g_E(i)S_{E,i}\bigr] +\frac{t^2}4\sum_{i,j}\Bigl[g_F(i,j)\bigl(S_{F,i}S_{F,j} +\kappa_{FF}A^{\rm arm}_{F,i}A^{\rm arm}_{F,j}\bigr)\\ &+g_E(i,j)S_{E,i}S_{E,j} +\kappa^{\rm al}_b\,g^{\rm sel}_E(i,j)A^{\rm arm}_{E,i}A^{\rm arm}_{E,j}\Bigr]\\ &+\sum_{T\in\{F,E\}}\sum_{3\le|m|\le4}\frac{t^{|m|}g^{\rm sel}_T(m)} {2^{|m|-1}\prod_im_i!} \Bigl[\sum_\sigma\prod_{l=1}^{|m|}P^{\sigma_l}_{T,i_l} +\one_{|m|=4}\,\kappa_{4,T}\prod_{l=1}^4A^{\rm arm}_{T,i_l}\Bigr], \end{split} \end{equation} where $i_1\le\dots\le i_{|m|}$ are the pieces of the multiset $m$, $\sigma$ runs over the words in $\{{\rm s},{\rm a}\}^{|m|}$ with an even number of letters ${\rm a}$, not all equal to ${\rm a}$, $P^{\rm s}_{T,i}=S_{T,i}$ and $P^{\rm a}_{T,i}=A_{T,i}$; and where $\kappa_{FF}$ is the cap of the envelope FF of the fold pairs, $\kappa^{\rm al}_b$ the invariant cap of the envelope EE aligned of the aligned matching pairs, $\kappa_{4,F}$ the cap of the envelope F4E0 of the class $(4,0)$ and $\kappa_{4,E}$ the invariant cap of the aligned group of the envelope E4 of the class $(0,4)$ (\cref{thm:envelopes,lem:class-credit}; \cref{tab:data:envelopes}). The factors $\frac14$ and $2^{1-|m|}$ account for the two records of one kind of a block, which carry equal prices, of which the variance classes retain the two aligned assignments. \begin{corollary}[The variance credits of the final construction] \label{cor:variance:final} Assume the gates of \cref{cert:variance:fresh}. Let $m$ be a multiset of pieces, $X$ a set of $|m|$ distinct middle blocks of pattern $m$, and $j\in\{1,2\}$. \begin{enumerate}[label=(\roman*)] \item For $|m|\in\{1,2\}$ and symmetric parities, the selection of $F_j$ on $X$ has the class cost $B-g_F(m)$, and the class of the two aligned matching assignments has the class cost $B-g_E(m)$. \item For $|m|=2$ and skew parities, the aligned fold assignment $(F_j,F_j)$ and the set of the two aligned matching assignments satisfy \cref{lem:var-gain}(a) with $C=C_m$ and the numbers $b_F(m)$, $b_E(m)$, whose gains are $g_F(m)$ and $g^{\rm sel}_E(m)$. \Cref{lem:class-credit} turns them into the credits $\kappa_{FF}g_F(m)$ and, on the branch with $\mu$ outside and without background or pool terms, $\kappa^{\rm al}_bg^{\rm sel}_E(m)$, against the envelope costs of the aligned classes. Crossed matching pairs receive no variance credit. \item For $|m|\in\{3,4\}$ and an even number of skew parities, not all skew, the selection of $F_j$ on $X$ and the class of the two aligned matching assignments have the class costs $B-g^{\rm sel}_F(m)$ and $B-g^{\rm sel}_E(m)$. For $|m|=4$ and four skew parities, the aligned assignments of one kind receive instead, inside the envelope class $(4,0)$ or $(0,4)$, the credit $\kappa_{4,T}g^{\rm sel}_T(m)$ on their raw-arm prices (\cref{lem:class-credit}). \item At the per-block upper prices, with $B_*\ge B$ in place of $B$ (\cref{rem:cp:monotone}) and every repeated-block monomial of a piece multiset given the gain of that multiset, these credits lower the complete polynomial of \cref{lem:record:record-expansion} by at least $D_{\rm var}$ \eqref{eq:variance:dvar}, and every coefficient stays nonnegative. \end{enumerate} \end{corollary} \begin{proof} By the paragraphs above the piece values, the caps and the numbers $\Sigma_i$ are piece data; the gates of \cref{cert:variance:fresh} give $k_{F,i},k_{E,i}<1$ and every gain in $[0,1)$; and $R_{\rm err}\le R_*$ by the choice of $R_*$. (i) \Cref{prop:background-variance}(b) for the fold selection and \cref{prop:background-variance}(a) for the aligned matching class. (ii) \Cref{cor:var-classes}(i), (ii) with $C=C_m$ give \cref{lem:var-gain}(a) with $\bar l_F=b_F(m)$ and $\bar l^{\rm al}_E=b_E(m)$, and $[\bar l_F-R_*]_+=g_F(m)$, $[\bar l^{\rm al}_E-R_*]_+=g^{\rm sel}_E(m)$. These selections belong to the envelope classes $(2,0)$ and $(0,2)$ of \cref{cor:envelope-costs}, and the averaged bound of \cref{lem:var-gain}(a) is the hypothesis of \cref{lem:class-credit}, whose parts (a) and (b) take the fractions $\kappa_{FF}$ and $\kappa^{\rm al}_b$ of the gains; the background terms of \cref{prop:background-variance} are not used for this class. The restorations live on the two aligned corners of the matching bridge (\cref{lem:record:paired-e-joint}), so no lower bound is available for a crossed class. (iii) By \cref{cor:var-classes}(i), (ii) with $C=C_m$ and \cref{lem:var-gain}(c) the stated classes have the costs $B-g^{\rm sel}_F(m)$, $B-g^{\rm sel}_E(m)$; they lie in no envelope class, since the classes of \cref{cor:envelope-costs} consist of skew factors only. For four skew factors the selection lies in the class $(4,0)$ or $(0,4)$, and \cref{lem:class-credit}(c) credits $\kappa_{4,T}g^{\rm sel}_T(m)$ on its raw-arm monomials, on its aligned words. (iv) The per-block upper price of a record of one kind with a parity is half of the block's share of $tS_{T,i}$ or $tA_{T,i}$, and its raw-arm price half of the share of $tA^{\rm arm}_{T,i}$. On the monomials of the selections of (i) and (iii) with a symmetric factor, \cref{lem:record:record-expansion}(iv) allows the coefficient $B_*-g$, because the class cost is $B-g\le B_*-g$; on the monomials with a repeated block of the same records, kinds and parities it allows any coefficient in $[0,B_*c_{\boldsymbol n}]$, and they receive the gain of their piece multiset, which is below $1\varrho_{34}$ with \begin{equation}\label{eq:feature-perron} \lambda-\varrho_{02}-\frac{\varrho_{03}^2}{\lambda-\varrho_{34}} -\frac{2\varrho_{01}^2}\lambda\ge0 . \end{equation} \item In $L^2(m_{E,\Blk})$ the three matching features have pairwise correlations at most $1/(b-1)$, and their synthesis map has squared norm at most $\Gamma_E=1+1/(b-1)$. \end{enumerate} The four fold constants are nondecreasing in $(q,r)$, so at every middle block they are at most their values at $q=1/Q_3$, $r=Q_3^{-1/2}$, $Q_3=19951586$: \[ \begin{array}{c|l} \varrho_{02}&2.23877949420725\cdot10^{-4}\\ \varrho_{01}&5.01213362368300\cdot10^{-8}\\ \varrho_{03}&5.01437833890212\cdot10^{-8}\\ \varrho_{34}&2.23928121269334\cdot10^{-4} \end{array} \] For every middle block one may therefore take \begin{equation}\label{eq:oct24:feature-constants} \Gamma_F=\frac{500111979555137707696357560603}{5\cdot10^{29}}<1.000223959111, \qquad \Gamma_E=\frac{19951586}{19951585}, \end{equation} and the bound $\rho_{\rm pair}=50121336236829934606443\cdot10^{-30}<5.0121336237\cdot10^{-8}$ for $\varrho_{01}$, with $\eta_{\rm pair}=2\rho_{\rm pair}/(1-\rho_{\rm pair}^2)<1.0024267248\cdot10^{-7}$. \end{lemma} \begin{proof} \emph{Step 1: blocks and sectors.} The conditional expectation of a function of one whole object given another, or given a pair of others, is the tensor product of the prime conditional expectations, which are Markov operators of couplings with exact marginals. These preserve the exact supports of the nonconstant prime factors (\cref{lem:sector}(a)), and the sectors of distinct supports are orthogonal in the product law. By \cref{lem:sector}(a),(c), on every nonempty support the product is bounded by the largest one-prime bound. The prime formulas of the statement and of Step~3 are nonnegative and nondecreasing in $(q,r)$ (\cref{lem:majorant}); every prime of $\Blk$ is at least $b$, so every one-prime bound is at most its value at $b$. \emph{Step 2: the singleton edges $01$, $02$, $12$.} At a prime the pair law of $(x_0,x_2)$ is uniform on directed pairs, so the correlation of $\mathcal H_0$ and $\mathcal H_2$ is the norm of the square shift on mean-zero functions, $r\sqrt{1+q}/(1-q)$ (\cref{lem:square-shift}(b), \cref{lem:paley-triple}\ref{it:paley:triples}); the pair laws of $(x_0,x_1)$ and $(x_1,x_2)$ have the density $1-\mu\chi(y'-y)$, whose operator on mean-zero functions is a combination of $I$ and the Paley operator, with norm $\varrho_{01}$ (\cref{lem:actual-features}(b)). By Step~1 these are the block bounds. \emph{Step 3: the edges $03$ and $24$.} Let $f$ be a mean-zero function of one label, $y,z$ distinct labels and $s=\chi(z-y)$. Direct conditioning in the actual triple weight $\one[x_0\to x_2](d-1-\one[x_0\to x_1]-\one[x_1\to x_2])$, $d=(p-1)/2$ (\cref{lem:old-f-law}(a), \cref{lem:actual-features}(a)), gives \begin{gather*} \E_{m_0}[f(x_0)\mid x_1=y,x_2=z]=\frac{N_f(y,z)}{(p-3)(p-4-2s)},\\ N_f(y,z)=-p(p-5-s)Pf(z)+pPf(y)+pWf(y,z)-(p-5)f(z)-(p-6)(1+s)f(y), \end{gather*} with the Paley operator $P$ and $Wf(y,z)=-\E_t[\chi(t-y)\chi(t-z)]f(t)$; for instance the common-predecessor sum is $4\sum_{a\to y,\,a\to z}f(a)=-p[Pf(y)+Pf(z)+Wf(y,z)]-(1-s)f(z)-(1+s)f(y)$, and the formula follows after expanding the two predecessor indicators. Since $s^2=1$, $1/(p-4-2s)=(p-4+2s)/((p-6)(p-2))$, so the conditional expectation is $N_f\,(p-4+2s)/((p-3)(p-6)(p-2))$. Expand it, using $s^2=1$, and project onto $\mathcal K_{12}$: every function of $y$ alone or of $z$ alone is annihilated. What remains is $-sf(y)/(p-3)$, $-2(p-5)sf(z)/((p-3)(p-6)(p-2))$ and terms in $sPf(z)$, $sPf(y)$, $Wf$ and $sWf$ whose coefficients have absolute values adding up to $2p/((p-6)(p-2))$. As $|s|=1$, the singleton marginals are uniform, $\|Pf\|\le r\|f\|$, and $W^*W\preceq qI$ (\cref{lem:actual-features}(c), where $W$ is the operator $A_3$), the projection has norm at most \[ \frac1{p-3}+\frac2{(p-3)(p-6)}+\frac{2p}{(p-6)(p-2)}\,r=\varrho_{03}(p). \] This is the one-prime correlation of $\mathcal H_0$ and $\mathcal K_{12}$, and by Step~1 the bound on the sectors of size one. On a support of size $k\ge2$ we use two coarser prime estimates. Put $\varrho=r\sqrt{1+q}/(1-q)$ and \[ \tilde\varrho_{03}=\frac{2(1+\varrho)/(p-3)+e_0}{\sqrt{1-e_0}},\qquad \varrho_{0|12}=\frac{(\sqrt{p+1}+2)/(p-3)+e_0}{\sqrt{1-e_0}} . \] For a mean-zero $f$ let $Tf(z)=\E_{\nu_F}[f(x_0)\mid x_2=z]$, the average of $f$ over the $d$ predecessors of $z$. Given $x_1=y$ and $x_2=z$, the label $x_0$ is uniform under $\nu_F$ on these predecessors, with $y$ excluded if it is one of them; so, with $j=\one_{y\to z}$, \[ \E_{\nu_F}[f(x_0)\mid y,z]=\frac{d\,Tf(z)-jf(y)}{d-j} =Tf(z)+\frac j{d-j}\bigl(Tf(z)-f(y)\bigr). \] Since $j/(d-j)\le2/(p-3)$, Minkowski's inequality and the uniform singleton marginals bound the norm of $f\mapsto\E_{\nu_F}[f(x_0)\mid x_1,x_2]$ by $\varrho+2(1+\varrho)/(p-3)=(\sqrt{p+1}+2)/(p-3)$. In $L^2(m_0)$ the density perturbation costs $e_0$, and the norm of a function of the pair changes by at most the factor $(1-e_0)^{-1/2}$ (\cref{lem:paley-triple}\ref{it:paley:perturb}). So the correlation of $\mathcal H_0$ and $\operatorname{ran}(P_{12}-\Jproj)$ is at most $\varrho_{0|12}$. Let $h$ be a function of $(x_1,x_2)$ orthogonal in $L^2(m_0)$ to all functions of $x_2$. Then $\E_{m_0}[Tf(x_2)h]=0$, so $\ip{f(x_0)}{h}_{m_0}=\E_{m_0}[(f(x_0)-Tf(x_2))h]$. Its uniform part is $\E_{\nu_F}[\frac j{d-j}(Tf(x_2)-f(x_1))h]$, at most $2(1+\varrho)/(p-3)$ times the uniform norms; its density-error part is at most $e_0\|f(x_0)-Tf(x_2)\|_{\nu_F}\|h\|_{\nu_F}\le e_0\|f\|\|h\|_{\nu_F}$, because $T$ is a conditional expectation under $\nu_F$. Converting only the pair norm, the correlation of $\mathcal H_0$ and $\operatorname{ran}(P_{12}-P_2)$, which contains $\mathcal K_{12}$, is at most $\tilde\varrho_{03}$. This comparison uses the actual orthogonality of $h$; it does not transport a uniform pair projection as an actual projection. Let $T_p$ map a function of $x_{0,p}$ to its actual conditional expectation given $(x_{1,p},x_{2,p})$, and put $T_{2,p}=P_{2,p}T_p$. Both fix the constants on both sides; on mean-zero functions both have norm at most $\varrho_{0|12}$, and $\|T_p-T_{2,p}\|\le\tilde\varrho_{03}$. On a support with $k\ge2$ active primes the telescoping bound of \cref{lem:sector}(b) gives $\|\bigotimes_pT_p-\bigotimes_pT_{2,p}\|\le k\tilde\varrho_{03}\varrho_{0|12}^{k-1}$. In terms of $(q,r)$, $\varrho_{0|12}=[(r\sqrt{1+q}+2q)/(1-3q)+e_0]/\sqrt{1-e_0}$ and $\tilde\varrho_{03}/q=[2(1+\varrho)/(1-3q)+e_0/q]/\sqrt{1-e_0}$ with $e_0/q=2/((1-3q)(1-4q))$ are nondecreasing in $(q,r)$ (\cref{lem:majorant}). At $p=2^{24}$, hence at every middle prime, $\varrho_{0|12}<\frac12$ and $2(\tilde\varrho_{03}/q)\varrho_{0|12}<1$ (\cref{cert:envelopes}(a)); so $k\tilde\varrho_{03}\varrho_{0|12}^{k-1}\le2\tilde\varrho_{03}\varrho_{0|12}\varrho_{34}$ the lower right block of $\lambda I$ minus this matrix is positive definite, and its Schur complement is the left side of \eqref{eq:feature-perron}; so \eqref{eq:feature-perron} gives $\lambda I\succeq$ the Perron block, which proves (b). \emph{Step 6: the matching frame.} The matching half law is uniform on injective triples, so at a prime $V_i^*V_j=-I/(p-1)$ on $L^2_0$ for $i\ne j$ (condition one coordinate on another). On an exact support $S$ of the block every off-diagonal singleton Gram entry is $c_SI$ with $c_S=(-1)^{|S|}\prod_{p\in S}(p-1)^{-1}$, so the correlations are at most $1/(b-1)$, and the Gram matrix of the three features has the eigenvalues $1-c_S$, $1-c_S$, $1+2c_S$. Odd supports give at most $1+1/(b-1)$, and even nonempty supports at most $1+2/(b-1)^2$, which is smaller. This proves (c). \emph{The numbers.} Exact rational bounds for the square roots give the table, the gates of Step~3 and \eqref{eq:oct24:feature-constants}; $\Gamma_F$ is the rational end of a bisection for \eqref{eq:feature-perron} with the rounded entries, and $\Gamma_E=1+1/(Q_3-1)$, every middle prime exceeding $Q_3$ (\cref{cert:envelopes}(a)). \end{proof} \subsection{Dominating matrices for tensors of star operators} \label{subsec:envelope-tools} \begin{lemma}[A positive substitute for a pure-pair projection] \label{lem:oct24:pure-pair-substitute} In $L^2$ of an actual half marginal of a prime or of a block suppose that the correlation of $\mathcal H_i$ and $\mathcal H_j$ is at most $\rho<1$, and let $\Pi_{ij}$ be the orthogonal projection onto $\mathcal K_{ij}$. Then \[ Q_{ij}=P_{ij}-\frac{P_i+P_j}{1+\rho}+\frac{1-\rho}{1+\rho}\Jproj \] satisfies \begin{equation}\label{eq:oct24:pure-pair-substitute} 0\preceq Q_{ij}-\Pi_{ij}\preceq\eta\,(C_i+C_j),\qquad \eta=\frac{2\rho}{1-\rho^2}. \end{equation} Let $\widetilde V_i\colon L^2\to L^2(m)$ be the extension of $V_i$ to all functions of one label, $\widetilde V_if(x)=f(x_i)$; thus $\widetilde V_i\one=\one$, whereas $V_i$ has domain $L^2_0$. Every $P_i$, $P_{ij}$ and $\Jproj$ is the Markov operator of a normalized nonnegative coupling of the actual marginal with itself, and so is, for singleton coordinates $i\ne j$, the operator $M_{ij}=\widetilde V_i\widetilde V_j^*$: choose a uniform label, then sample the two halves independently, conditioned on their coordinates $i$ and $j$, respectively, taking that label. Both half marginals of these couplings are the actual marginal, $M_{ii}=P_i$, and $V_iV_j^*=M_{ij}-\Jproj$. Placed by its record, each such coupling is an admissible positive law: it has uniform one-slot marginals and is invariant under independent simultaneous translations at the primes of the block, as \ref{it:record:E1} requires. \end{lemma} \begin{proof} On $\mathcal H_i+\mathcal H_j$ the spectrum of $C_i+C_j$ lies in $[1-\rho,1+\rho]$: it is that of the Gram operator of the two inclusions of $\mathcal H_i$ and $\mathcal H_j$, whose off-diagonal block has norm at most $\rho$. There $Q_{ij}=I-(C_i+C_j)/(1+\rho)$, whereas $\Pi_{ij}=0$; the lower bound follows from the upper spectral endpoint, and the upper bound from $I\preceq(C_i+C_j)/(1-\rho)$. On $\mathcal K_{ij}$ both operators equal the identity; on the constants and on the orthogonal complement of the functions of $(x_i,x_j)$ both vanish. These four subspaces reduce all the operators involved. To realize $P_i$ as a coupling, sample $x_i$ from its actual marginal and then the two triples independently from their actual conditional laws given that value; for $P_{ij}$ use the pair instead, and for $\Jproj$ sample two independent triples. For $M_{ij}$ the half with the coordinate $i$ equal to the chosen label has the actual marginal because the coordinate $i$ is uniform, and likewise for $j$; for $g$ on the second half, $\E[g(x')\mid x]=(\widetilde V_j^*g)(x_i)=(\widetilde V_i\widetilde V_j^*g)(x)$, so its Markov operator is $M_{ij}$, and $\widetilde V_i\Jproj_{\rm lab}\widetilde V_j^*=\Jproj$ for the projection $\Jproj_{\rm lab}$ onto the constant labels. One-slot marginals are uniform because they are those of the actual marginal. The constructions commute with the square-affine symmetries of that marginal, including independent simultaneous translations at its primes. The operator $Q_{ij}$ is positive semidefinite, but its signed expansion is not a nonnegative coupling; this is why the envelopes below are expanded into the couplings $M_{ij}$, $P_{ij}$, $\Jproj$ before any energy is bounded. \end{proof} For a fold record we write $Q_{12}$ and $Q_{01}$ for the substitutes with $\rho=\rho_{\rm pair}$ and $\eta=\eta_{\rm pair}$ of \cref{lem:oct24:feature-block}, which bounds the correlations of $\mathcal H_1,\mathcal H_2$ and of $\mathcal H_0,\mathcal H_1$ by $\varrho_{01}\le\rho_{\rm pair}$. \paragraph{Signed stars.} A \emph{star} on an orthogonal sum $\bigoplus_v\mathcal H_v$ is a skew-adjoint operator $\sum_a(\mathrm{in}_aA_a\mathrm{in}_c^*-\mathrm{in}_cA_a^*\mathrm{in}_a^*)$ with one \emph{centre} $c$, mutually orthogonal \emph{arms} $a\ne c$, the coordinate inclusions $\mathrm{in}_v$ and operators $A_a\colon\mathcal H_c\to\mathcal H_a$, whose norms are the \emph{arm norms}. On $(L^2_0)^5$ and $(L^2_0)^3$, with rows and columns indexed by the fold labels $0,\dots,4$ and the matching labels $0,1,2$, let \begin{equation}\label{eq:signed-star} \mathsf F(\Phat)=\begin{pmatrix}0&\Phat&\tlaw\Phat&\tlaw-1&0\\ \Phat&0&0&0&0\\ \tlaw\Phat&0&0&0&0\\ 1-\tlaw&0&0&0&0\\ 0&0&0&0&0\end{pmatrix}, \qquad \mathsf E(\Phat)=\begin{pmatrix}0&\Phat&0\\ \Phat&0&0\\ 0&0&0\end{pmatrix}, \end{equation} with $\Phat=P/r$ the normalized Paley operator at a prime (\cref{lem:paley-triple}), skew-adjoint with $\Phat^2=-I$ on $L^2_0$. They are stars with centre $0$: $\mathsf F$ has the arms $1,2,3$ with the arm operators $\Phat$, $\tlaw\Phat$, $(1-\tlaw)I$ and arm norms $1$, $\tlaw$, $1-\tlaw$; $\mathsf E$ has the arm $1$ with the arm operator $\Phat$. For a map $\Xi=(\Xi_v)_v$ from $(L^2_0)^5$ (or $(L^2_0)^3$) into a Hilbert space we call $\Xi\,\mathsf F\,\Xi^*=\sum_{a,b}\Xi_a\mathsf F_{ab}\Xi_b^*$ the \emph{lift} of $\mathsf F$ by $\Xi$. At a middle prime $p$ of a block let $\Xi_p=(V_0,V_1,V_2,A_3^\circ/r_p,0)$ for a fold record, with the pure-pair arm $A_3^\circ$ of \eqref{eq:signed-leading}, a map of norm at most $r_p$ into the sector $\{p\}$ of $\mathcal K_{12}$ (\cref{lem:actual-features}(c),(e)), and $\Xi_p=(V_0,V_1,V_2)$ for a matching record, all restricted to the singleton sector $\{p\}$ of the label space. The lift of $\mathsf F(\Phat_p)$ by $\Xi_p$ is $r_p^{-1}$ times the leading signed star $L^\circ_{\tlaw,p}=A^\circ_\tlaw V_0^*-V_0(A^\circ_\tlaw)^*$ of \eqref{eq:signed-leading}, $A^\circ_\tlaw=r_p(V_1\Phat_p+\tlaw V_2\Phat_p) +(1-\tlaw)A_3^\circ$; the pure-pair arm is a contraction after the division by $r_p$, and it is not assumed to commute with $\Phat$. The lift of $\mathsf E(\Phat_p)$ is $V_1\Phat_pV_0^*+V_0\Phat_pV_1^*$. For a middle block $\Blk$ with least prime $b$, $r_\Blk=b^{-1/2}$, and an eligible record $\phi$ (\cref{def:record:eligible}), let $\zeta^{\rm a}_{\Blk,\phi}$ be the skew part at $\iota$ of the change of $\phi$ in $\nu_\Blk-\lambda_\Blk$, and $m_{\phi,\Blk}$ its actual half marginal at $\iota$. The \emph{raw-arm coefficient} of $\phi$ is $w_{\rm D}r_\Blk^2$ for $F_1,F_2$ and $w_{\rm S}r_\Blk^2$ for $E_0,E_1$, with the record weights of the piece of $\Blk$. The \emph{normalized skew change} $\widehat\Delta_{\phi,\Blk}$ is the cut operator of $\zeta^{\rm a}_{\Blk,\phi}$ at $\iota$, relative to $m_{\phi,\Blk}$, divided by the raw-arm coefficient. Write $\ell_\tlaw(b)$, $a_F(b)$ for the constants of \cref{prop:signed-bounds} at $q=1/b$, $r=b^{-1/2}$, and $r_E(X)$ for the constant of \cref{lem:oct24:matching-star} at the start $X$ of the piece of $\Blk$. We use the following \emph{star form}. \begin{enumerate}[label=(N\arabic*)] \item\label{it:env:N1} $\widehat\Delta_{F_1,\Blk}=L+\Upsilon$, where $L$ is the orthogonal sum over the singleton sectors $\{p\}$, $p\in\Blk$, of $c_p$ times the lift of $\mathsf F(\Phat_p)$ by $\Xi_p$, with numbers $00$ be weights on the tensor features such that for every complementary pair of masks $A,A^c$ \begin{equation}\label{eq:oct24:mask-schur} \Bigl(\sum_{A(v)=A}\frac{\alpha(v)^2}{d_v}\Bigr) \Bigl(\sum_{A(w)=A^c}\frac{\alpha(w)^2}{d_w}\Bigr)\le1 . \end{equation} Then the tensor product of the stars lies between $\pm$ the diagonal operator with the weights $d_v$, extended by any nonnegative weights to the features that are neither centres nor arms. In particular a diagonal $D\in\mathcal A$ satisfying \eqref{eq:oct24:mask-schur} for the stars \eqref{eq:signed-star}, with the arm magnitudes $1,\tlaw,1-\tlaw$ at the fold arms $1,2,3$ and $1$ at the matching arm $1$, is an envelope. \item \emph{Finite tests.} The conditions \eqref{eq:matrix-envelope} follow from the following finite tests, in which $\mathsf F(i)=f_r+if_i$ with real $f_r,f_i$ and $H=f_i-if_r$, and in the second, third and fourth cases $D$ is diagonal in the matching labels, $D=\sum_eD_e\otimes e_{ee}$ over the matching words $e$: \begin{itemize} \item FF and FE: $D\pm\mathsf F(i)\otimes\mathsf F(\pm i)\succeq0$, respectively $D\pm\mathsf F(i)\otimes\mathsf E(\pm i)\succeq0$; \item one fold and an odd number $m$ of matching factors: $D_e\succeq0$ for every matching word $e$, and $\bigl(\begin{smallmatrix}D_e&H\\H&D_{\bar e}\end{smallmatrix}\bigr)\succeq0$ for the complementary active words $e,\bar e\in\{0,1\}^m$; \item two fold and two matching factors: the same blocks with the cross matrix $\mathsf F(i)\otimes\mathsf F(\pm i)$; \item three fold and one matching factor: $D_e\in\mathcal A_F^{\otimes3}$ invariant under permutations of the fold coordinates, and the blocks with the cross matrix $\mathsf S(\xi_1)\otimes\mathsf S(\xi_2)\otimes\mathsf S(\xi_3)$ for the phase counts $0$ and $1$, where $\mathsf S(\xi)=i\,G^*\mathsf F(\xi)G$, $G=\operatorname{diag}(1,1,1,i,i)$, is real symmetric (the \emph{pure-pair gauge}); \item four fold factors: $D$ invariant under permutations of the fold coordinates, and $D\pm\bigotimes_{k=1}^4\mathsf S(\xi_k)\succeq0$ for the phase counts $0$, $1$, $2$. \end{itemize} \end{enumerate} Every test is a rational matrix inequality; a Hermitian test is certified by its real form of twice the size (\cref{rem:realified-gates}), and a real test $\mathbf M\succeq0$ by an integer matrix $\mathbf L$ and a scale $g$ such that $g^2\mathbf M-\mathbf L\mathbf L^{\sf T}$ is entrywise diagonally dominant with nonnegative diagonal. \end{lemma} \begin{proof} (a) The tensor $\bigotimes_\Blk L_\Blk$ is the orthogonal sum, over the choices $(p_\Blk)_{\Blk\in X}$ of one singleton sector at every block, of $(\prod_\Blk c_{p_\Blk})$ times the lift by $\Xi=\bigotimes_\Blk\Xi_{p_\Blk}$ of $T=\bigotimes_{X_F}\mathsf F(\Phat_{p_\Blk})\otimes\bigotimes_{X_E}\mathsf E(\Phat_{p_\Blk})$, and it vanishes on the other sectors. The operators $\Phat_{p_\Blk}$ act on distinct tensor factors, so they commute; they are normal with spectrum in $\{i,-i\}$, and $D\otimes I\pm T$ is a polynomial in them with matrix coefficients. By the joint spectral decomposition it is the orthogonal sum of the matrices \eqref{eq:matrix-envelope} over the joint eigenspaces, hence positive semidefinite. As $D\succeq0$ and $0\le\prod c\le1$, also $D\otimes I\pm(\prod c)T\succeq0$, and the congruence by $\Xi$ gives $\Xi(D\otimes I)\Xi^*\pm(\prod c)\,\Xi T\Xi^*\succeq0$. The ranges of the maps $\Xi$ of distinct choices lie in mutually orthogonal sectors, so $\pm\bigotimes_\Blk L_\Blk\preceq\sum_{(p_\Blk)}\Xi(D\otimes I)\Xi^*$. It remains to compare the right side with $\operatorname{Lift}(D)$ by positive enlargements. $D$ acts on the labels and the sector projections $\Pi_S$ on the label spaces, so they commute. Summing over all choices of one sector $S_\Blk$ at every block, instead of singleton sectors only, adds the congruences of the positive operators $D\otimes\bigotimes_\Blk\Pi_{S_\Blk}$, the maps at the labels $3$, $4$ being taken zero on the sectors of size at least two. The sum is the lift of $D$ by $\bigotimes_\Blk(V_0,V_1,V_2,Z_\Blk,0)$ at the fold blocks and $\bigotimes_\Blk(V_0,V_1,V_2)$ at the matching blocks, on the whole centred label spaces, where $Z_\Blk$ is the orthogonal sum of the maps $A_3^\circ/r_p$; as these have orthogonal ranges in the sectors of $\mathcal K_{12}$ and norm at most one, $Z_\Blk$ is a contraction into $\mathcal K_{12}$. In this lift a unit $e_{ab}$ of two singleton labels gives $V_aV_b^*$. The labels $3$ and $4$ are separate scalar blocks of $\mathcal A_F$, so every term with the label $3$ (or $4$) at a fold coordinate is a positive operator on the other coordinates tensored with $Z_\Blk Z_\Blk^*$ (or $0$) at that coordinate; and $Z_\Blk Z_\Blk^*\preceq\Pi_{\mathcal K_{12}}\preceq Q_{12}$, $0\preceq Q_{01}$ by \eqref{eq:oct24:pure-pair-substitute}. Replacing a factor of a tensor product of positive operators by a larger positive operator increases it, so these replacements, made one coordinate at a time, give $0\preceq\sum_{(p_\Blk)}\Xi(D\otimes I)\Xi^*\preceq\operatorname{Lift}(D)$ and hence $\pm\bigotimes_\Blk L_\Blk\preceq\operatorname{Lift}(D)$. Every unit $V_aV_b^*$ and $Q_{ij}$ annihilates the constants on both sides, which gives the second assertion, and the expansions $V_aV_b^*=M_{ab}-\Jproj$ and $Q_{ij}=P_{ij}-(P_i+P_j)/(1+\rho)+\frac{1-\rho}{1+\rho}\Jproj$ with $P_i=M_{ii}$ give the third (\cref{lem:oct24:pure-pair-substitute}). (b) Write $\Sigma_X=\bigotimes_\Blk\Sigma_\Blk$ for the tensor product of the synthesis maps of the fold and matching features, and let $D$ act on $\bigotimes_\Blk\bigoplus_v\mathcal H_v$ through the identifications $V_a$ of the singleton spaces with $L^2_0$ and by scalars on $\mathcal K_{12}$, $\mathcal K_{01}$. By \eqref{eq:oct24:pure-pair-substitute}, $Q_{12}\preceq\Pi_{\mathcal K_{12}}+\eta_{\rm pair}(C_1+C_2)$ and $Q_{01}\preceq\Pi_{\mathcal K_{01}}+\eta_{\rm pair}(C_0+C_1)$, and the replacements are positive enlargements of positive principal blocks as in (a); so $0\preceq\operatorname{Lift}(D)\preceq\Sigma_XD^\sharp\Sigma_X^*$, the lower bound by (a). The map $D\mapsto D^\sharp$ is the identity plus the map with the Kraus operators $\eta_{\rm pair}^{1/2}e_{13}$, $\eta_{\rm pair}^{1/2}e_{23}$, $\eta_{\rm pair}^{1/2}e_{04}$, $\eta_{\rm pair}^{1/2}e_{14}$, hence completely positive. So $\|\operatorname{Lift}(D)\|\le\|\Sigma_X\|^2\|D^\sharp\|\le\Gamma_F^n\Gamma_E^m\|D^\sharp\|$ by \cref{lem:oct24:feature-block}(b),(c). For diagonal $D$, $\Sigma_XD^\sharp\Sigma_X^*=\sum_vd^\sharp_v\iota_v\iota_v^*$ for the tensor products $\iota_v$ of the feature inclusions, and \cref{lem:weighted-frame}(a),(b) with the correlation bounds of \cref{lem:oct24:feature-block}(a),(c) gives the second bound. (c) A star maps its centre to its arms and its arms to its centre, so the tensor maps the sector of a mask only to the sector of the complementary mask, and annihilates the features outside the stars. After conjugation by $D^{-1/2}$, the block between two complementary sectors is bounded, on the vector of component norms, by the outer product of the vectors $(\alpha(v)/\sqrt{d_v})_v$ and $(\alpha(w)/\sqrt{d_w})_w$; its norm is at most the square root of the left side of \eqref{eq:oct24:mask-schur}. The even tensor is self-adjoint, so the norm bound proves both orders. The proof keeps the phases of the arm operators and uses no simultaneous diagonalization, and weights on inactive features are positive additions. The stars of \eqref{eq:signed-star} at $\Phat=\xi_\Blk$ have the stated arm magnitudes, which gives the last assertion. (d) $D$ is real and $\mathsf F(-i)$, $\mathsf E(-i)$ are the complex conjugates of $\mathsf F(i)$, $\mathsf E(i)$, so the condition at $\xi$ is the complex conjugate of the condition at $-\xi$; for FF and FE the four phase patterns reduce to the two listed. If $D$ is diagonal in the matching labels, the tensor maps an active matching word $e\in\{0,1\}^m$ to its complement $\bar e$ with the scalar factor $\pi_E=\prod_{X_E}\xi_\Blk$, in both directions, and annihilates the words containing the label $2$; so \eqref{eq:matrix-envelope} is the orthogonal sum of the conditions $D_e\succeq0$ on the inactive words and of the blocks $\bigl(\begin{smallmatrix}D_e&\pm\pi_ET_F\\ \pm\pi_ET_F&D_{\bar e}\end{smallmatrix}\bigr)\succeq0$, $T_F$ the tensor of the fold matrices. The congruence by $\operatorname{diag}(I,-I)$ exchanges the two signs. For one fold factor and odd $m$, $\pi_E=\pm i$ and $\pm i\mathsf F(\pm i)\in\{\pm H,\pm\bar H\}$, the conjugate case being automatic; $H$ is Hermitian because $f_i$ is real symmetric and $f_r$ real antisymmetric. For two fold and two matching factors $\pi_E=\pm1$. For three fold factors conjugate by $G^{\otimes3}$, which commutes with $\mathcal A_F^{\otimes3}$: then $G^*\mathsf F(\xi)G=-i\,\mathsf S(\xi)$, where $\mathsf S(\xi)$ has the entries $i\xi$, $i\tlaw\xi$ at the singleton arms and $1-\tlaw$ at the pure-pair arm, real for $\xi=\pm i$; the cross matrix becomes $\pi_E(-i)^3\mathsf S\otimes\mathsf S\otimes\mathsf S$, real up to the sign $\pm1$. By the permutation invariance the test depends only on the number of phases $-i$ among the fold phases, and complex conjugation identifies the counts $c$ and $3-c$. For four fold factors $(-i)^4=1$, so the gauged tensor is the real $\bigotimes_k\mathsf S(\xi_k)$; conjugation identifies the counts $c$ and $4-c$, and both signs are tested since no matching coordinate provides the congruence. The certificate of $\mathbf M\succeq0$ is $g^2\mathbf M=\mathbf L\mathbf L^{\sf T}+(g^2\mathbf M-\mathbf L\mathbf L^{\sf T})$, a sum of a Gram matrix and a diagonally dominant symmetric matrix with nonnegative diagonal. \end{proof} \begin{remark}[Where the gain comes from]\label{rem:envelope-gain} For one star $L$ with one arm of norm $\alpha$ and the diagonal $D$ with weights $d_c,d_a$, the operator $D^{-1/2}LD^{-1/2}$ is a contraction if and only if $d_cd_a\ge\alpha^2$, the one-factor case of \eqref{eq:oct24:mask-schur}. For an even tensor $T$ of skew stars, every $D$ with $-D\preceq T\preceq D$ has norm at least $\|T\|$, so an envelope by itself costs at least the norm of the tensor. The gain comes from the averaging of \cref{subsec:reflection-averaging}: the reflection fixes some feature vertices and moves the others in pairs, and the average replaces the weights at each moved vertex and at its reflected mate by their mean, while it keeps that of every fixed one. The envelopes are chosen with small weights on the fixed vertices and large weights on the moved ones. For two matching stars of arm norm one, the weights $x$ at the fixed vertex $(0,0)$ and $2x$ at the moved vertex $(1,1)$, with $2x^2\ge1$, give the averaged maximum $x\approx2^{-1/2}$ against the norm one of the tensor. On fully invariant backgrounds the whole action of the chamber group averages the matching names; for a crossed pair this gives the cap $(1+\sqrt3)/6$ (\cref{lem:reflection-averaging}(g)). Matrix envelopes in the singleton block algebra improve on diagonal ones because they may use the signed off-diagonal couplings $M_{ab}$, $a\ne b$; a coefficient joining a pure-pair label to another label is excluded, since it would not expand into couplings of bounded variation. \end{remark} \subsection{Averaging a dominating matrix over reflections}\label{subsec:reflection-averaging} The averaging is a change of variables in the energy, which permutes the slots and so leaves the product of the identical inputs unchanged; the work is to say exactly which measure is transported to which, and in which charts the transports are read. \paragraph{Record assignments and placed measures.} For a middle block $\Blk$ and an eligible record $\phi$ let $m_{\phi,\Blk}$ be its actual half marginal at $\iota$, read on object triples: $m_{0,\Blk}$ for $F_1,F_2$ and $m_{E,\Blk}$ for $E_0,E_1$. A \emph{record assignment} on a finite set $X$ of middle blocks is a map $\omega\colon X\to\{F_1,F_2,E_0,E_1\}$, and $m_\omega=\bigotimes_{\Blk\in X}m_{\omega(\Blk),\Blk}$; a selection of (CP4) all of whose types are skew and whose records are eligible is identified with its record assignment. For an operator $K$ on $L^2(m_\omega)$ let $[K]_\omega$ be the signed measure on the labels of $X$ obtained by placing, at every $\Blk\in X$ by the map $\omega(\Blk)\colon\Z/6\Z\to\{0,1,2\}$, the signed measure on two-layer object labellings whose cut operator at $\iota$ relative to $m_\omega$ is $K$: the slot $(u_0,u_1,\ell)$ receives the layer-$\ell$ label of the object $\omega(\Blk)(u_0)$. The placement is half-local, so the cut matrix of $[K]_\omega$ at $\iota$ is the pull-back of $K$ (\cref{lem:commoncut}(v)): $K\preceq K'$ implies $[K]_\omega\preceq_\iota[K']_\omega$, the map $K\mapsto[K]_\omega$ is linear and multiplicative over the blocks, $[I]_\omega=\operatorname{Diag}_\iota (m_\omega)$ is the diagonal copy of the actual half marginal, written $\operatorname{Diag}_\omega$, and $[\Jproj]_\omega=J_\iota(m_\omega)$ is the product of the actual half marginals, written $J_\omega$. The skew change of \cref{subsec:envelope-tools} is $\zeta^{\rm a}_{\Blk,\phi}=w\,r_\Blk^2\,[\widehat\Delta_{\phi,\Blk}]_\phi$, $w\,r_\Blk^2$ the raw-arm coefficient. The couplings $M_{ab}$ of \cref{lem:oct24:pure-pair-substitute} are placed in the same way. For a permutation $\beta$ of $\{0,1,2\}$ let $\mathcal P_\beta f(x)=f(x\circ\beta)$, with $(x\circ\beta)_o=x_{\beta(o)}$, a unitary of $L^2(m_E)$ (the law $m_E$ is invariant under name permutations) that maps $\mathcal H_i$ onto $\mathcal H_{\beta(i)}$; $\mathcal P_\beta V_i=V_{\beta(i)}$, so $\mathcal P_\beta\operatorname{Lift}(D)\mathcal P_\beta^*$ is the lift of the matrix $D$ with both indices permuted by $\beta$. \begin{lemma}[Reflection averaging]\label{lem:reflection-averaging} For $h\in\{1,3,5\}$ let $R_h$ be the slot permutation $(u_0,u_1,\ell)\mapsto(h-u_0,u_1,\ell)$: $R_5$, $R_1$, $R_3$ are the reflections of the chamber cuts $\vartheta_{0,0}$, $\vartheta_{0,1}$, $\vartheta_{0,2}$ of the first coordinate. For a finite signed measure $\kappa$ on labellings write $R_{h*}\kappa$ for the law of $z\circ R_h$. \begin{enumerate}[label=(\alph*)] \item \emph{Placements.} $R_h$ commutes with $\iota$ and with the rotation of the first coordinate, and maps the edge set of the twelve-label root onto itself. For a pattern $\phi\colon\Z/6\Z\to\{0,1,2\}$ and an object law $\kappa$, the reflection maps the law placed by $\phi$ to the law placed by $\phi\circ R_h$, and placing by $\beta\circ\phi$ is placing by $\phi$ the law relabelled by $\beta$. Substitution in the tuples gives the three reflection rows of \cref{tab:reflection}, written with $\psi_{h,s}=\psi_{s,R_h}$: \[ \begin{array}{c|c|c|c} h&(F_0,F_1,F_2)\circ R_h&\psi_{h,0}&\psi_{h,1}\\\hline 1&(F_1,F_0,F_2)&(0\,1)&(1\,2)\\ 3&(F_2,F_1,F_0)&(0\,2)&(0\,1)\\ 5&(F_0,F_2,F_1)&(1\,2)&(0\,2) \end{array} \qquad E_s\circ R_h=\psi_{h,s}\circ E_s, \] and $G_{sk}\circ R_h=G_{s,\psi_{h,s}(k)}$ for the merges. $F_0\circ R_5=F_0$, $F_1\circ R_3=F_1$ and $F_2\circ R_1=F_2$ are the only cases $F_j\circ R_h=F_j$. Consequently $R_{h*}$ maps a law placed by $F_j$ to the same object law placed by $F_j\circ R_h$, and a law placed by $E_s$ to the law placed by $E_s$ whose object names are permuted by $\psi_{h,s}$. \item \emph{Arithmetic transport.} Let $\varsigma(x)=(-x_2,-x_1,-x_0)$ and $\mathcal Uf=f\circ\varsigma$, on a block $\mathcal U=\bigotimes_p\mathcal U_p$. Then $\mathcal U$ is a self-adjoint unitary of $L^2(m_{0,\Blk})$ that maps $\mathcal H_0,\mathcal H_1,\mathcal H_2,\mathcal K_{12},\mathcal K_{01}$ onto $\mathcal H_2,\mathcal H_1,\mathcal H_0,\mathcal K_{01},\mathcal K_{12}$, that is, it permutes the fold labels by $\varphi=(0\,2)(3\,4)$; it conjugates $P_0,P_2,P_{12}$ into $P_2,P_0,P_{01}$, $M_{ab}$ into $M_{\varphi(a)\varphi(b)}$ and $Q_{12}$ into $Q_{01}$, so $\mathcal U\operatorname{Lift}(D)\mathcal U^*$ is the lift of $D$ with both fold indices permuted by $\varphi$. The record differences satisfy $D_{F_2}=\mathcal UD_{F_1}^*\mathcal U^*$, hence $D^{\rm a}_{F_2}=-\mathcal UD^{\rm a}_{F_1}\mathcal U^*$ and $D^{\rm s}_{F_2}=\mathcal UD^{\rm s}_{F_1}\mathcal U^*$, and \ref{it:env:N2} holds. $\mathcal U$ identifies operators only; it is never applied to the input $F_A$, and no negation symmetry of the set $A$ is used. \item \emph{Energy invariance.} Let $\alpha\in\mathcal G_6$ act on the first coordinate, let $X$ be a finite set of middle blocks and $O=\bigotimes_{\Blk\notin X}O_\Blk$ a product of measures with $O_\Blk\succeq_\iota0$ and $\alpha_*O_\Blk=O_\Blk$ for every atom $\Blk\notin X$. Then $Y_{\alpha_*\kappa\otimes O}=Y_{\kappa\otimes O}$ for every finite signed measure $\kappa$ on the labels of $X$, and $\kappa\succeq_\iota\kappa'$ implies $\alpha_*\kappa\succeq_\iota\alpha_*\kappa'$. \item \emph{Averaging.} In the setting of (c) with $\alpha=R_h$, let $\Omega$ be a finite set of record assignments on $X$ with numbers $\pi_\omega\ge0$, and $\omega\mapsto\bar\omega$ an involution of $\Omega$ (fixed points allowed) such that, at every $\Blk\in X$, $\bar\omega(\Blk)\circ R_h=\omega(\Blk)$ if $\omega(\Blk)$ is a fold record and $\bar\omega(\Blk)=\omega(\Blk)$ if it is a matching record, and $\pi_{\bar\omega}=\pi_\omega$. Let $\mathcal T_\omega$ be $\mathcal U$ at the fold blocks where $\bar\omega(\Blk)\ne\omega(\Blk)$ and the identity elsewhere, $\mathcal P_\omega$ the tensor product of the $\mathcal P_{\psi_{h,s}}$ at the matching blocks $E_s$, and $g_\omega=\mathcal P_\omega\mathcal T_\omega$. If operators $K_\omega$ on $L^2(m_\omega)$ satisfy $K_{\bar\omega}=\mathcal T_\omega K_\omega\mathcal T_\omega^*$, then \[ \sum_{\omega\in\Omega}\pi_\omega\,Y_{[K_\omega]_\omega\otimes O} =\sum_{\omega\in\Omega}\pi_\omega\, Y_{[\frac12(K_\omega+g_\omega K_\omega g_\omega^*)]_\omega\otimes O}. \] \item \emph{Charts.} Let $h=5$ and let $\bar\omega$ exchange $F_1$ and $F_2$ at every fold block. The \emph{coordinate unitary} of a record assignment is $\mathcal U_\omega=\bigotimes_\Blk\mathcal U_{\omega(\Blk)}$ with $\mathcal U_{F_1}=I$, $\mathcal U_{F_2}=\mathcal U$, $\mathcal U_{E_0}=I$ and $\mathcal U_{E_1}=\mathcal P_{(0\,1)}$; its \emph{chart reflection} $g_5=\mathcal U_\omega^*g_\omega\mathcal U_\omega$ is $\mathcal U$ at every fold factor and $\mathcal P_{(1\,2)}$ at every matching factor, whatever $\omega$ is, so it permutes the feature labels by $\varphi$ at the fold factors and by $(1\,2)$ at the matching factors, and $g_5\operatorname{Lift}(D)g_5^*=\operatorname{Lift}(g_{5*}D)$ for the image $g_{5*}D$ of $D$ under these label permutations. In the charts the normalized leading stars have one shape up to sign: $\mathcal U_\omega^*L\,\mathcal U_\omega$ is $\pm$ the star of \ref{it:env:N1} (centre $0$, arms $1,2,3$, signed coefficients) at a fold factor, and $\pm$ the one-arm star of \ref{it:env:N3} between $0$ and $1$ at a matching factor. If $K_\omega=\mathcal U_\omega K\mathcal U_\omega^*$ for one operator $K$ for all $\omega$ with the same fold and matching blocks, then $K_{\bar\omega}=\mathcal T_\omega K_\omega\mathcal T_\omega^*$ and $\frac12(K_\omega+g_\omega K_\omega g_\omega^*)=\mathcal U_\omega\,\frac12(K+g_5Kg_5^*)\, \mathcal U_\omega^*$. \item \emph{Extra reflection.} Let $O$ in (c) be invariant under $R_1$ and $R_3$ as well, and let $\omega$ be a record assignment whose fold records are all $F_1$, or all $F_2$; put $h=3$ in the first case and $h=1$ in the second. Then $R_{h*}$ maps $[K]_\omega$ to $[\mathcal P'K\mathcal P'^*]_\omega$, where $\mathcal P'$ is the identity at the fold blocks and $\mathcal P_{\psi_{h,s}}$ at a matching block carrying $E_s$; so $Y_{[K]_\omega\otimes O}=Y_{[\frac12(K+\mathcal P'K\mathcal P'^*)]_\omega\otimes O}$. In the chart of $\omega$, $T_\omega=\mathcal U_\omega^*\mathcal P'\mathcal U_\omega$ fixes every fold label and acts by $(0\,2)$ at the $E_0$ factors and by $(0\,1)$ at the $E_1$ factors if $h=3$, and by $(0\,1)$ and $(0\,2)$ if $h=1$. The two cases are conjugate by $g_5$: $T_{\bar\omega}=g_5T_\omega g_5^{-1}$ on the labels. In a class $\Omega(X_F,X_E)$ with $n\ge1$ fold blocks these assignments form the fraction $2^{1-n}$. No reflection at individual primes or individual matching blocks is used. \item \emph{Pure matching words.} Let $X$ consist of matching blocks and $O$ in (c) be invariant under $\mathcal G_6$. Every $\alpha\in\mathcal G_6$ maps the placement of $E_s$ to itself with the names permuted by $\psi_{s,\alpha}$, where $E_s\circ\alpha=\psi_{s,\alpha}\circ E_s$; $\alpha\mapsto\psi_{0,\alpha}$ is onto the symmetric group of $\{0,1,2\}$, and $\psi_{1,\alpha}=c\,\psi_{0,\alpha}c^{-1}$ with $c=(0\,1\,2)$. So $Y_{[K]_\omega\otimes O}$ equals the same energy with $K$ replaced by its average over $\mathcal G_6$. In the chart the action is $A_\tau(\sigma)=\bigotimes_j\sigma^{(\tau_j)}$, $\sigma^{(0)}=\sigma$, $\sigma^{(1)}=\epsilon\sigma\epsilon$, $\epsilon=(1\,2)$, for the type vector $\tau$ of $\omega$ (after fixing an ordering $\Blk_1,\dots,\Blk_m$ of $X$, $\tau_j=1$ if $\Blk_j$ carries $E_1$) and $\sigma=\psi_{0,\alpha}$; since $A_{1-\tau}(\sigma)=A_\tau(\epsilon\sigma\epsilon)$, complementary words have the same averaging group, and when the envelope of one word is transported to the other words with the same number of $E_1$ coordinates by permuting the coordinates, the averaged caps depend only on $\{k,m-k\}$, $k$ the number of $E_1$ coordinates. For $m=4,6$ the groups $\{k,m-k\}$ have the weights $(\frac18,\frac12,\frac38)$ and $(\frac1{32},\frac3{16},\frac{15}{32},\frac5{16})$. For two matching factors of different types, the diagonal weights $a,b,c,d$ at the active chart vertices $(0,0),(0,1),(1,0),(1,1)$ pass the mask conditions $ad\ge1$, $bc\ge1$ and average to $a/3$ on the diagonal orbit and $(b+c+d)/6$ off it; $a=(1+\sqrt3)/2$, $b=c=1$, $d=1/a$ give both the value $(1+\sqrt3)/6$. For two factors of one type the diagonal orbit receives $(a+d)/3\ge\frac23$. \end{enumerate} \end{lemma} \begin{proof} (a) $R_h$ acts on the first coordinate only, where it commutes with the rotation (\cref{lem:slot-array}(i)) and preserves the root (\cref{lem:layer12-geometry}(a)); $\iota$ acts on the layer. Under the law placed by $\phi$ the slot $(h-u_0,u_1,\ell)$ carries the label $y_{\phi(h-u_0),\ell}$, which is $y_{(\phi\circ R_h)(u_0),\ell}$; and $y_{\beta(\phi(u_0)),\ell}$ is the label of the object $\phi(u_0)$ in the relabelled family $y\circ\beta$. The table is the substitution of \cref{tab:reflection} ($R_1,R_3,R_5$ are $\vartheta_1,\vartheta_2, \vartheta_0$ there, and $\psi_{h,s}$ is $\psi_{s,R_h}$), the merges follow from $G_{sk}=\one[E_s=k]$ and $\psi_{h,s}^{-1}=\psi_{h,s}$ (\cref{lem:record:fold-identification}(e)), and the fixed folds are read off the table. (b) $\varsigma$ is an involution that preserves $\nu_F$ and $g_0$ (\cref{lem:record:asymmetric-gram}(c)), so $\mathcal U$ is a self-adjoint unitary of $L^2(m_0)$ that fixes the constants. It maps the functions of $x_i$ onto the functions of $x_{2-i}$, and those of $(x_1,x_2)$ onto those of $(x_1,x_0)$; this gives the action on the $\mathcal H_i$, on the pair spaces, hence on $\mathcal K_{12},\mathcal K_{01}$, and on the projections. With the negation $Nf(u)=f(-u)$ on $L^2_0$, $\mathcal UV_a=V_{2-a}N$, and $N$ commutes with every real scalar matrix unit and with $\Jproj$; so $\mathcal UM_{ab}\mathcal U^*=M_{\varphi(a)\varphi(b)}$ and the lift is transported as stated. The comparison record of $F_2$ is the reflected transpose of that of $F_1$ (\cref{def:record:mixture}(d)), $K'_2=\mathcal UK'^*\mathcal U^*$ as operators, and $\mathcal UK_0\mathcal U^*=K_0$ with $K_0$ self-adjoint (\cref{lem:record:asymmetric-gram}(c)); hence $D_{F_2}=K'_2-K_0=\mathcal U(K'-K_0)^*\mathcal U^*$ at every prime, and on a block by tensor products, the signed record being taken componentwise. Taking the skew and symmetric parts gives the next two identities. With \ref{it:env:N4}, dividing by the common coefficient and taking the transports of the leading star and of the remainder of $F_1$ gives \ref{it:env:N2}. The energies below are integrals of $\prod_vF_A(z_v)$ against placed measures, and $\mathcal U$ enters only through the identity of the operators of two records; the change of variables of (c) is a permutation of slots. (c) For every finite signed measure $\rho$ on labellings, $Y_\rho=\int\prod_{v\in V}F_A(z_v)\,d\rho(z)$ with the same lift at every slot, and $z\mapsto z\circ\alpha$ permutes the factors of the product; so $Y_{\alpha_*\rho}=Y_\rho$. The permutation acts on every atom, and $\alpha_*(\kappa\otimes O)=\alpha_*\kappa\otimes O$ by the invariance of the $O_\Blk$. Since $\alpha$ fixes the layer, it maps $V_+$ onto itself and commutes with $\iota$, so it acts on cut matrices at $\iota$ by a simultaneous permutation of rows and columns (\cref{rem:cut-symmetries}(c)). (d) By (a), $R_{h*}$ maps the measure placed by the records of $\bar\omega$ with object operator $K$ to the measure placed by the records of $\omega$ with object operator $\mathcal P_\omega K\mathcal P_\omega^*$: the fold records of $\bar\omega$ go to those of $\omega$ with the same object law, and the matching laws keep their placement and have their names permuted, the matching marginal $m_E$ being invariant under name permutations. With $K=K_{\bar\omega}=\mathcal T_\omega K_\omega\mathcal T_\omega^*$ and (c), $Y_{[K_{\bar\omega}]_{\bar\omega}\otimes O}=Y_{[g_\omega K_\omega g_\omega^*]_\omega\otimes O}$. Since $\omega\mapsto\bar\omega$ is a bijection of $\Omega$ and $\pi_{\bar\omega}=\pi_\omega$, the left side of the identity equals $\sum_\omega\pi_\omega Y_{[g_\omega K_\omega g_\omega^*]_\omega\otimes O}$; average the two expressions. (e) For $h=5$, (a) gives $\mathcal T_\omega=\mathcal U$ at every fold block and $\mathcal P_\omega=\mathcal P_{(1\,2)}$ at $E_0$, $\mathcal P_{(0\,2)}$ at $E_1$. At a fold factor $\mathcal U_\omega\in\{I,\mathcal U\}$ commutes with $\mathcal U$, so the chart reflection is $\mathcal U$; at $E_1$ it is $\mathcal P_{(0\,1)}\mathcal P_{(0\,2)}\mathcal P_{(0\,1)}=\mathcal P_{(1\,2)}$. Moreover $\mathcal U_{\bar\omega}=\mathcal T_\omega\mathcal U_\omega$, because $\mathcal U^2=I$; this gives $K_{\bar\omega}=\mathcal T_\omega K_\omega\mathcal T_\omega^*$, and $g_\omega\mathcal U_\omega=\mathcal U_\omega g_5$ gives the averaged form. The action on lifts is (b) and the paragraph before the lemma. By \ref{it:env:N2} the coordinate unitary of an $F_2$ factor turns its star into $-1$ times a star of the $F_1$ shape. The matching star $V_1\Phat V_0^*+V_0\Phat V_1^*$ is invariant under $\mathcal P_{(0\,1)}$, so the coordinate unitary of an $E_1$ factor keeps the shape. (f) By (a), $F_1\circ R_3=F_1$ and $F_2\circ R_1=F_2$, so $R_{h*}$ maps the fold placements of $\omega$ to themselves with the same object laws, and at a matching block permutes the names by $\psi_{h,s}$; with (c) and the invariance of $O$ under $R_h$ this is the identity of energies, and averaging the two expressions gives the averaged form. The coordinate unitary of $\omega$ is $I$ at all fold factors in the first case and $\mathcal U$ at all of them in the second, which commutes with $\mathcal P'$ there; at the matching factors the native permutations $\psi_{3,0}=(0\,2)$, $\psi_{3,1}=(0\,1)$, respectively $\psi_{1,0}=(0\,1)$, $\psi_{1,1}=(1\,2)$, read in the chart $\mathcal U_{E_1}=\mathcal P_{(0\,1)}$, become $(0\,2),(0\,1)$, respectively $(0\,1),(0\,2)$, as $(0\,1)(1\,2)(0\,1)=(0\,2)$. Conjugation by $(1\,2)$ exchanges $(0\,1)$ and $(0\,2)$, which is the last assertion. Among the $2^{n+m}$ assignments of the class, $2^m$ have all fold records $F_1$ and $2^m$ all $F_2$. For $n=1$ the reflections used on a partner pair are the pairing and then $R_h$ at the common placement; the operators so obtained at the two assignments of the pair, four in all, have the same energy, although the two operations do not define a group action on the assignments. (g) Every $\alpha\in\mathcal G_6$ maps the placement of $E_s$ to itself with the names permuted (\cref{lem:record:fold-identification}(e)). The maps $\alpha\mapsto\psi_{s,\alpha}$ are homomorphisms; the relation $\psi_{1,\alpha}=c\,\psi_{0,\alpha}c^{-1}$ holds for the generators $R_1,R_3,R_5$ by the table of (a), and the six images $\psi_{0,\alpha}$ are distinct. With (c) the energy is the same for every $\alpha$, and averaging gives the group average. In the chart the $E_1$ factors carry $(0\,1)c\,\sigma c^{-1}(0\,1)=\epsilon\sigma\epsilon$, since $(0\,1)c=c^{-1}(0\,1)=\epsilon$. As $\sigma\mapsto\epsilon\sigma\epsilon$ is a bijection of the symmetric group, the sets $\{A_\tau(\sigma)\}$ and $\{A_{1-\tau}(\sigma)\}$ coincide, so the averages coincide. A word with $k$ coordinates $E_1$ among $m$ has the weight $\binom mk2^{-m}$, which gives the weights of the groups. For two factors of different types conjugate the second coordinate by $\epsilon$: the active vertices become $(0,0),(0,2),(1,0),(1,2)$ and the action becomes the diagonal action $\sigma\otimes\sigma$, whose orbits on the label pairs are the three diagonal pairs and the six others; averaging a diagonal weight function over the orbits gives $a/3$ and $(b+c+d)/6$. For two factors of one type the active vertices are $(0,0),(0,1),(1,0),(1,1)$, the diagonal orbit receives $(a+d)/3\ge2(ad)^{1/2}/3\ge\frac23$. \end{proof} The identities of (d), (f) and (g) are between price-weighted energies of placed operators; they are not identities between the terms $I_\omega$ of the record expansion, and partners do not cancel. They are applied only to energies with $F_A$ at every slot and with an invariant outside law: not to energies carrying index structure (the signed index, the common mean, the energies of \cref{lem:envelope-energy}), and not with $\Nbr$, $\lambda$, $\rho$ or $\nu$ outside, which are not invariant (\cref{lem:oct24:invariant-background}). The extra averages (f), (g) are used only on fully invariant outside monomials. \subsection{Outside laws invariant under reflections, and their price} \label{subsec:oct24:pure-background} \begin{lemma}[Invariant outside laws]\label{lem:oct24:invariant-background} Let $h\in\{1,3,5\}$. \begin{enumerate}[label=(\roman*)] \item For every choice of the completion weights $w,v$, the middle reference $\mu_\Blk$ of \cref{lem:front12:reference} is $R_h$-invariant. \item For every choice of the state weights $(w_{\mathfrak t},v_{\mathfrak t})_{\mathfrak t\in\{\rm L,D,S,R,C\}^2}$, the upper reference of \cref{def:upper-reference} is $R_h$-invariant, and so is every tail law (\cref{def:tail-law}). \item Every prefix law (\cref{def:clique-law}) is invariant under all permutations of the first coordinate. \item At a middle block, $E_{\rm add}$ and $H$ are $R_h$-invariant and $G$ is $R_5$-invariant (\cref{def:record:frame}). The bracket carries one copy of the one-layer folded copies of the fold records, so its background, the outside measure $\Nbrz$ of \cref{lem:bracket-energy} against which the energies of selected laws are priced, is $\Nbr_{0,\Blk}=\mu_\Blk+E_{\rm add}+G+H=\Nbr^{\rm inv}_\Blk+G_\Blk$ (\cref{lem:record:gram}); $F_{\rm fold}$ is a summand of $\Nbr=\lambda+F_{\rm fold}+H$, not of $\Nbrz$. The \emph{invariant background} $\Nbr^{\rm inv}_\Blk=\mu_\Blk+E_{\rm add}+H$ is invariant under $R_1,R_3,R_5$ and the group $\mathcal G_6$ they generate, $\Nbr_{0,\Blk}$ is $R_5$-invariant, and $\Nbr^{\rm inv}_\Blk$, $G_\Blk$ and $\Nbr_{0,\Blk}$ are $\succeq_\iota0$. Off the middle blocks $\Nbr_{0,\Blk}=\Nbr^{\rm inv}_\Blk:=\mu_\Blk$ is invariant under $\mathcal G_6$ and $\succeq_\iota0$. \item \emph{Assigned prices.} For the middle piece $i$ with start $X_i$, weights $v_{{\rm D},i}$, $w_{{\rm S},i}$, polarization coefficient $(f_1+h_1)_i$ (an upper end) and the exact rational upper ends $I^{\rm ex}_{2,i}$, $I^{\rm ex}_{3,i}$ of its degree charges at the source exponent $a_0$, from which the native outside price of the piece is computed, put \begin{equation}\label{eq:invariant-price} u^{\rm inv}_i=2v_{{\rm D},i}I^{\rm ex}_{2,i}+\frac{12w_{{\rm S},i}}{1-3/X_i}I^{\rm ex}_{3,i}, \qquad u^G_i=2v_{{\rm D},i}(f_1+h_1)_iI^{\rm ex}_{3,i},\qquad \Uinv=\sum_iu^{\rm inv}_i . \end{equation} Then $u^{\rm inv}_i$ and $u^G_i$ bound the summed prices at $a_0$ of the invariant tags $E_{\rm add}+H$ and of the generic tag $G$ over the blocks of the piece, and $u^{\rm inv}_i+u^G_i\le u_i$, the upper end of the term of the piece in the native outside price, with $\sum_iu_i\le U_0'$, the upper bound of $U_0$ at $a_0$ (\cref{lem:record:middle-prices}). At the exponent $a$ all these prices are at most $t$ times their values. Consequently, if $0\le\kappa_b\le\kappa_H$ and an outside polynomial has the coefficient $\kappa_b$ on the monomials whose middle factors are all $\mu$ or invariant tags and $\kappa_H$ on all others, its completed value at the exponent $a$ is at most \[ \kappa_He^{U_0}-(\kappa_H-\kappa_b)e^{t\Uinv} \qquad\text{for every }U_0\ge t\Bigl(\Uinv+\sum_iu^G_i\Bigr), \] for instance $U_0=tU_0'$. The same factor $e^{t\Uinv}$ is the background factor of the orbit coupon (\cref{lem:orbit-coupon}). \end{enumerate} $G$ is not $R_1$- or $R_3$-invariant, and $\Nbr_\Blk$, $\lambda_\Blk$, $\rho_\Blk$, $\nu_\Blk$ are not asserted to be invariant under any $R_h$: $E_{\rm new}$ and the repaired records accept the six queries, whose first-coordinate pair $(0,2)$ is sent by $R_5$ to $(5,3)$. \end{lemma} \begin{proof} (i) By \cref{lem:front12:reference}(iii), $\widetilde\mu_\Blk=\sum_tw_tr^{\deg t} \pi_{t,2}+r\sum_tv_tr^{\deg t}\operatorname{Diag}_\iota(\pi_{t,1})$, where $\pi_{t,j}$ is the sum of the $j$-layer components of type $t$. For each $j$ these components are those of the five-type datum of the $j$-layer root, $F$ and $E$ laws, with the exchangeable $E$ law and the $\mathcal G_6$-invariant root (\cref{lem:record:fold-identification}(a)); by \cref{lem:five-type}(a) and its proof every type sum $\pi_{t,j}$ is $\mathcal G_6$-invariant, because precomposition with a chamber automorphism permutes the folds and the merges of each partition, fixes the constants, and maps each matching to itself with its names permuted. The positive roots of the late pieces are invariant as well, by the score or support-dictionary invariance (\cref{lem:positive-root-properties}(b), \cref{lem:imp:coherent39-law}). The weights depend only on the type, and $R_{h*}$ commutes with $\operatorname{Diag}_\iota$ and with the pull-back to $V$, since $R_h$ fixes the layer and the second coordinate. Hence $\widetilde\mu_\Blk$, its mass and $\mu_\Blk$ are invariant. (ii) The upper reference is the two-coordinate five-type measure of \cref{def:two-coordinate-five-type}, with the field laws, components and row data of \cref{subsec:layer72:upper}, the state weights $w_{\mathfrak t}$ and the reserved weights $v_{\mathfrak t}$. By \cref{lem:five-type}(d), for each type $\mathfrak t_1$ and pattern $\phi'\in P_{\mathfrak t_1}$ of the second coordinate, its components with second type $\mathfrak t_1$ and second pattern $\phi'$ form the image, under the emission $e_{\phi'}$, of a one-coordinate five-type measure of the row data of the first coordinate, with weights that depend only on the states. These row data are five-type data (\cref{subsec:layer72:upper}): the chamber reflections of an $\rm L$ coordinate are automorphisms of the graphs, and the $\rm E$ field laws are exchangeable in their object coordinate (\cref{lem:upper-geometry}(b)). So each such measure is $\mathcal G_6$-invariant by \cref{lem:five-type}(a), and the emission commutes with the action on the first coordinate. The two-layer part, and in the same way the diagonal copies of the one-layer part, are therefore invariant for any weights. A tail law is a law of the same kind at one prime. (iii) Given the clique data, the six first-coordinate labels are independent and identically distributed and the common square-affine map does not depend on the chamber, so the pull-back is invariant under every permutation of the first coordinate. (iv) $E_{\rm add}$ and $H$ are combinations of the diagonal copies $\operatorname{Diag}_\iota(\Pi^{(1)}_{E_s})$, and $R_{h*}$ maps $\operatorname{Diag}_\iota(\Pi^{(1)}_{E_s})$ to the diagonal copy of the one-layer $E$ law placed by $\psi_{h,s}\circ E_s$, which is the same measure, the $E$ law being exchangeable. $G$ is a multiple of the diagonal copies placed by $G_{00}$ and $G_{11}$, which $R_5$ fixes ($\psi_{5,0}(0)=0$, $\psi_{5,1}(1)=1$), and which $R_1$ and $R_3$ send to merges outside $G$. The diagonal copies are reserved diagonal, hence $\succeq_\iota0$ (\cref{lem:commoncut}(i)), and $\mu_\Blk\succeq_\iota0$. The decomposition of $\Nbrz$ is \cref{def:record:frame}(d) and \cref{lem:record:gram}(i). Off the middle blocks $\Nbr_{0,\Blk}=\mu_\Blk$: the invariance is (ii) and (iii), and $\mu_\Blk\succeq_\iota0$ is \ref{it:record:R2} at $\iota$. (v) The masses of $E_{\rm add}$, $H$ and $G$ at a block of the piece are at most $2v_{\rm D}r^2$, $12w_{\rm S}r^3/(1-3/X_i)$ and $2v_{\rm D}(f_1+h_1)r^3$, divided by the normalizing mass $\widetilde\mu_\Blk(1)\ge1$ (\cref{def:record:frame}(b), \cref{lem:record:middle-prices}); a price is the mass times $q_\Blk^{2a}$, and summing over the blocks of the piece with the upper charges $I^{\rm ex}_{d,i}$ of the sums of $r_\Blk^dq_\Blk^{2a_0}$ gives the first claim. The formulas are the degree-two coefficient and the two summands of the degree-three coefficient of $\Nbrz-\mu$ in \cref{lem:record:middle-prices}, evaluated at the same exact charges as the native outside price, so $u^{\rm inv}_i+u^G_i$ is the term of the piece in that price, of which $u_i$ is the stored upper end (\cref{cert:envelopes}(c) checks $u^{\rm inv}_i+u^G_i\le u_i$ and $\sum_iu_i\le U_0'$). Every middle block has $\log q_\Blk\le L=570$, so $q_\Blk^{2a}\le tq_\Blk^{2a_0}$ (\cref{lem:record:repricing}). For the completed value, expand the outside polynomial in the actual positive tags $E_{\rm add}+H$ and $G$ before completing repeated blocks: with $v_\Blk$, $w_\Blk$ the prices at $a$ of the invariant and of the generic tag of $\Blk$, it is $\kappa_H\prod_\Blk(1+v_\Blk+w_\Blk)-(\kappa_H-\kappa_b)\prod_\Blk(1+v_\Blk)$ over the middle blocks outside the selection, which only increases when the selected blocks are included, the polynomial being nondecreasing in every variable. By \cref{lem:record:record-expansion}(iii) choose, in every piece, upper prices $m_\Blk\ge v_\Blk$ with $\sum_{\Blk\in i}m_\Blk=tu^{\rm inv}_i$ and $n_\Blk\ge w_\Blk$ with $\sum_{\Blk\in i}n_\Blk=tu^G_i$; then $\sum_\Blk m_\Blk=t\Uinv$ and $\sum_\Blk(m_\Blk+n_\Blk)=t(\Uinv+\sum_iu^G_i)\le U_0$. The chosen-tag-price form of \cref{rem:completion-subtraction} then bounds the polynomial by $\kappa_He^{U_0}-(\kappa_H-\kappa_b)e^{\sum_\Blk m_\Blk}=\kappa_He^{U_0}-(\kappa_H-\kappa_b)e^{t\Uinv}$. Upper prices are assigned to separate positive components, and no lower bound is inferred from an upper estimate; the transport by $t$ multiplies all tag prices together. The last sentence is the proof of \cref{lem:orbit-coupon}. \end{proof} The invariance in (i) and (ii) is that of the five-type completion on a product of six-chamber coordinates; it is the same chamber invariance that the completions of the $216$-slot design had (\cref{subsec:history:216}). The price $\Uinv$ is a chosen assignment, not a bound: a smaller number may replace it (the difference being treated as generic), a larger one may not, since the completed value decreases in $\Uinv$ at fixed $U_0$. \begin{lemma}[Invariant coupling orbits for exactly one folded error] \label{lem:orbit-coupon} Let $X$ be a finite set of middle blocks, $\omega$ a record assignment on $X$, and $K=\sum_Cc(C)[C]_\omega$ a collected finite real combination of placed couplings, $C$ running over tensor products of the couplings of \cref{lem:oct24:pure-pair-substitute}; put $M=\sum_C|c(C)|$. Let $h\in\{1,3\}$ be such that $R_h$ maps every fold placement of $\omega$ to itself ($h=3$ if all fold records of $\omega$ are $F_1$, $h=1$ if all are $F_2$, either if $\omega$ has none); then $R_{h*}[C]_\omega=[hC]_\omega$ for a permutation $C\mapsto hC$ of the couplings (\cref{lem:reflection-averaging}(f),(g)). Let $s=(h-1)/2$, the tag whose cut, the chamber cut $\vartheta_{0,1+s}$ of the first coordinate, has the reflection $R_h$ (\cref{def:record:frame}(e)), and put \[ M_h(K)=\sum_C\one\bigl[c(C)c(hC)>0\bigr]\min\bigl(|c(C)|,|c(hC)|\bigr), \] a coupling with $hC=C$ counting with its full $|c(C)|$. Let $d'=D'/2$ be the upper bound at $a_0$ of the sharp price of one folded tag, half the sharp total $D'$ of the first stage (\cref{lem:record:middle-prices}: per block of the piece $i$ the sharp price of a tag is at most $(v_{{\rm S},i}+v_{{\rm D},i})k_{\rm new}(X_i)r_\Blk^3q_\Blk^{2a_0}$), let \[ s'=\sum_i\operatorname{up}\bigl((v_{{\rm S},i}+v_{{\rm D},i})s_{\rm fold}(X_i)I^{\rm hi}_{4,i}\bigr) \] be the upper bound of its symmetric price, the symmetric part of a tag difference having the sharp coefficient $s_{\rm fold}(X)b^{-1}$ (\cref{lem:record:one-stage-folded-e}(d),(e)), with the upper degree charges $I^{\rm hi}_{4,i}$ and the rounding $\operatorname{up}$ of \cref{def:closing-quantities}, and put $\delta_{\rm s}=d'-s'$; $0\le s'\le d'$ (\cref{cert:envelopes}(d)). Let $U_0\ge t(\Uinv+\sum_iu^G_i)$ as in \cref{lem:oct24:invariant-background}(v), $d=td'$ and $v$ upper totals at $a$ of the sharp and variation prices of each tag, and $R_{\rm err}\ge e^{U_0}\tagser(d,v)$, for instance the value of \cref{def:closing-quantities}(2). \begin{enumerate}[label=(\roman*)] \item $|Y^{\Nbr}[K]-Y^{\Nbrz}[K]|\le\bigl(MR_{\rm err}-M_h(K)\,e^{t\Uinv}t\delta_{\rm s}+o(1)\bigr) C_XY$. \item If $\omega$ has no fold record, the two reflections may be used at once: the subtraction becomes $(M_1(K)+M_3(K))e^{t\Uinv}t\delta_{\rm s}$, and $M_1+M_3\le2M$. \item Every other category of the error keeps its bound: the categories with several folded differences or with mixed tags, and, outside this comparison, the matching, index, unequal-input and restoration energies. \item \emph{Gate.} The coefficient $MR_{\rm err}-M_h(K)e^{t\Uinv}t\delta_{\rm s}$ (in (ii) with $M_1+M_3$) is nonnegative: $M_h\le M$, $e^{t\Uinv}\le e^{U_0}$, $t\delta_{\rm s}\le d$ and $R_{\rm err}\ge e^{U_0}(d_0+d_1)=2e^{U_0}d$. The closing checks it in the form coupon $\le MR_{\rm err}$, non-strictly. No strict form is needed: it is a nonnegativity condition on a coefficient of a bound of the second kind of \cref{lem:record:rec}(i), whose inflated constant $(1+z)c+c'z$ stays nonnegative. \end{enumerate} For a class of selections the \emph{invariant orbit mass} $M^{\rm inv}$ is the average over the class of $M_h(K_\omega)$ for the selections admitting an $h$ (in (ii) of $M_1+M_3$), and zero for the others, $K_\omega$ the collected expansion of the envelope of $\omega$. \end{lemma} \begin{proof} (i) For a two-element orbit $\{C,hC\}$ whose coefficients have the same sign put $b=\operatorname{sgn}(c(C))\min(|c(C)|,|c(hC)|)$; then \[ c(C)C+c(hC)\,hC=2b\,\frac{C+hC}2+\bigl(c(C)-b\bigr)C+\bigl(c(hC)-b\bigr)hC . \] The first coupling is positive, normalized and $R_h$-invariant, and the absolute coefficient mass is partitioned exactly into $2|b|$ and the residual mass. Fixed couplings are the one-element case, and opposite-sign orbits retain no mass. So $K=\sum_kc_kC_k$ with $\sum_k|c_k|=M$, in which $R_h$-invariant couplings carry the mass $M_h(K)$; and $Y^{\Nbr}[K]-Y^{\Nbrz}[K]=\sum_kc_k(Y^{\Nbr}[C_k]-Y^{\Nbrz}[C_k])$. Every $C_k$ is an admissible probability measure. Its difference is bounded as in the proof of \cref{lem:bracket-energy}: \cref{lem:sharp-first} with $F$ the first-stage atoms outside $X$, $\rho_\Blk=\Nbr_{0,\Blk}$, and the two tags. Let $C_k$ be $R_h$-invariant, and consider the category of the count vector $e_s$: exactly one record difference, of tag $s$. Its terms are energies $Y_{C_k\otimes\delta\otimes O}$, $\delta$ the difference of tag $s$ at one atom $\Blk'\in F$, $O$ the product of $\Nbrz$ at the other first-stage atoms and of $\mu$ elsewhere. Expand $\Nbr_{0,\Blk}=\mu_\Blk+(E_{\rm add}+H)_\Blk+G_\Blk$. In a term without $G$, $C_k$ and the outside product are $R_h$-invariant (\cref{lem:oct24:invariant-background}(i)--(iv)), so their cut matrices at $\vartheta=\vartheta_{0,1+s}$, whose reflection is $R_h$, are symmetric. The energy is the diagonal cut form at $\vartheta$ evaluated at the half-function carrying $F_A$ at every slot, by \eqref{eq:cc:bilinear}, the cut matrix of the product being the Kronecker product \eqref{eq:cc:kron}; by \cref{rem:cut-symmetries}(a) the skew part $\frac12(\delta-R_{h*}\delta)$ contributes nothing, so $\delta$ may be replaced by its symmetric part $\frac12(\delta+R_{h*}\delta)$ at $\vartheta$. The reflection fixes the shared label of the folded record and transposes its conditional kernel, so this part has the sharp bound $s_{\rm fold}(X)b^{-1}$ of \cref{lem:record:one-stage-folded-e}(e) relative to the replaced record at $\vartheta$, and the argument of \cref{lem:sharp-first} charges the term with the symmetric price $(v_{\rm S}+v_{\rm D})s_{\rm fold}(X)r_{\Blk'}^4q_{\Blk'}^{2a}$ instead of the sharp price. The terms with $G$ keep the sharp price. With $v_\Blk$, $w_\Blk$ the prices of the invariant and generic tags and $d_{\Blk'}$, $s_{\Blk'}$ the sharp and symmetric prices of the difference at $\Blk'$, and dropping, as in \cref{lem:sharp-first}, the requirement that the atoms be distinct, the category is at most $(1+o(1))C_XY$ times \[ \sum_{\Blk'}\Bigl[d_{\Blk'}\Bigl(\prod_\Blk(1+v_\Blk+w_\Blk)-\prod_\Blk(1+v_\Blk)\Bigr) +s_{\Blk'}\prod_\Blk(1+v_\Blk)\Bigr], \] a polynomial with nonnegative coefficients that is nondecreasing in every variable. Insert upper prices: for $d_{\Blk'}$ and $s_{\Blk'}$ the repriced block coefficients, distributed as in \cref{lem:record:record-expansion}(iii) so that they sum to $d=td'$ and to $ts'$, and for $v_\Blk,w_\Blk$ the chosen prices of the proof of \cref{lem:oct24:invariant-background}(v). As $\prod(1+m+n)-\prod(1+m)\le e^{\sum(m+n)}-e^{\sum m}$ coefficientwise and $s\prod(1+m)\le se^{\sum m}$, the category is at most $(de^{U_0}-t\delta_{\rm s}e^{t\Uinv}+o(1))C_XY$. Its bound in \cref{lem:bracket-energy} is $(de^{U_0}+o(1))C_XY$, the term of $e_s$ in $e^{U_0}\tagser(d,v)$; the other categories keep their bounds. So the difference for an invariant $C_k$ is at most $(R_{\rm err}-t\delta_{\rm s}e^{t\Uinv}+o(1))C_XY$, and for the others at most $(R_{\rm err}+o(1))C_XY$. Summing with $|c_k|$ gives (i). (ii) For $\omega$ without fold records both $R_1$ and $R_3$ fix the placements. The categories $e_0$ and $e_1$ are disjoint; treat the first with the orbit decomposition of $R_1$ and the second with that of $R_3$, the difference being linear in the coupling. Each mass is at most $M$. (iii) Only the category $e_s$ and only its terms without $G$ were changed. (iv) $M_h\le M$ because $\min(|c(C)|,|c(hC)|)\le|c(C)|$. The variation and sharp totals of the two tags are equal, $d_0=d_1=d$, and the terms $e_0$, $e_1$ of $\tagser$ are $d_0$ and $d_1$, so $R_{\rm err}\ge2e^{U_0}d$; and $t\delta_{\rm s}\le td'=d$. Hence the coupon is at most $Me^{U_0}d\le MR_{\rm err}/2$ in (i) and at most $2Me^{U_0}d\le MR_{\rm err}$ in (ii). Under the inflation of \cref{def:robust} the improved category is bounded by the same argument with every structured energy multiplied by $1+z$, so the coefficient becomes $(1+z)c+c'z$ with $c\ge0$, $c'\ge0$. \end{proof} \subsection{(CP5) bounds for products of skew changes}\label{subsec:envelope-theorem} \paragraph{Skew selections and envelopes.} Let $X$ be a finite set of middle blocks, partitioned into a set $X_F$ of $n$ \emph{fold blocks} and a set $X_E$ of $m$ \emph{matching blocks}, $n+m\ge2$ even. The \emph{skew selections} on $(X_F,X_E)$ are the $2^{n+m}$ selections of \cref{def:cp4}(c) on $X$ with the skew type at every block, one of $F_1,F_2$ at every fold block and one of $E_0,E_1$ at every matching block; $\Omega(X_F,X_E)$ is their set, and the \emph{partner} $\bar\omega$ of $\omega$ exchanges $F_1$ and $F_2$ at every fold block. All of them have the same actual half marginal $m_\omega=\bigotimes_{X_F}m_{0,\Blk}\otimes\bigotimes_{X_E}m_{E,\Blk}$, and by \ref{it:env:N4} the same auxiliary monomials. An \emph{envelope family} for a set $\mathcal C\subseteq\Omega(X_F,X_E)$ closed under the pairing is an envelope $D_{(\omega)}$ of \cref{lem:oct24:mask-schur} for every $\omega\in\mathcal C$, read in the chart of $\omega$, with $D_{(\bar\omega)}=D_{(\omega)}$; in all classes of the construction except $(0,4)$, $(0,6)$ it is one envelope $D$, and for $(0,4)$, $(0,6)$ it depends on the group $\{k,m-k\}$ of \cref{lem:reflection-averaging}(g). Put $D_\omega=\mathcal U_\omega\operatorname{Lift}(D_{(\omega)})\mathcal U_\omega^*$ and let $\bar D_\omega$ be its average with $g_\omega D_\omega g_\omega^*$ (\cref{lem:reflection-averaging}(d),(e)), the lift of $\frac12(D_{(\omega)}+g_{5*}D_{(\omega)})$ in the chart. The numbers of the family are class averages over $\mathcal C$: \begin{itemize} \item $\kappa_H$, the class average of the \emph{caps} of the $\bar D_\omega$, certified upper bounds for $\|\bar D_\omega\|$ given by \cref{lem:oct24:mask-schur}(b) (for one envelope $D$, the common value $\Gamma_F^n\Gamma_E^m\|(\frac12(D+g_{5*}D))^\sharp\|$ or its weighted-frame form); \item $\kappa_b\le\kappa_H$, the class average of the caps after the additional averages \cref{lem:reflection-averaging}(f), (g) where they apply, and of the caps of the $\bar D_\omega$ elsewhere (an additional average is an average of unitary conjugates, and the frame bounds are invariant under the label permutations involved, so its cap is at most that of $\bar D_\omega$); for one envelope invariant under permutations of its matching coordinates and $n\ge1$, $\kappa_b=(1-2^{1-n})\kappa_H+2^{1-n}\sum_{k=0}^m2^{-m}\binom mkb_k$, $b_k$ the cap of the doubly averaged envelope on the words with $k$ coordinates $E_1$; \item the coupling mass $M$, the average of $M(D_{(\omega)})$; \item the invariant orbit mass $M^{\rm inv}$ of \cref{lem:orbit-coupon}. \end{itemize} For a selection $\omega$ write $\pi^{\rm arm}_\omega$, $\pi^{\rm lead}_\omega$, $\pi^{\rm tot}_\omega$ and $\pi_\omega$ as in \cref{subsec:envelope-tools}, and let $L_\omega$ be the tensor product of its normalized leading stars. \begin{theorem}[Positive joint envelopes]\label{thm:envelopes} Assume (CP1)--(CP4) and (CP8) of \cref{thm:comparison} and the star form \ref{it:env:N1}--\ref{it:env:N4}. Let $(X_F,X_E)$ be as above with $n+m\le6$, let $\mathcal C\subseteq\Omega(X_F,X_E)$ be closed under $\omega\mapsto\bar\omega$, with an envelope family and its numbers $\kappa_H$, $\kappa_b$, $M$, $M^{\rm inv}$. Let $U_0$, $R_{\rm err}$ and $B=e^{U_0}+R_{\rm err}$ be upper bounds at the exponent $a$ as in \cref{lem:orbit-coupon}, and $\delta_{\rm s}$ its price saving. \begin{enumerate}[label=(\roman*)] \item \emph{Reduction.} For every $\omega\in\mathcal C$, $\pm L_\omega\preceq D_\omega$, and $\sum_{\omega\in\mathcal C}|I_\omega|\le\sum_{\omega\in\mathcal C}(\phi_\omega+o(1)\pi_\omega)Y$ with the class bound \begin{equation}\label{eq:envelope-class-bound} \begin{split} \phi_\omega={}&\bigl[\kappa_He^{U_0}-(\kappa_H-\kappa_b)e^{t\Uinv}+MR_{\rm err} -M^{\rm inv}e^{t\Uinv}t\delta_{\rm s}\bigr]\pi^{\rm arm}_\omega\\ &+B\bigl(\pi^{\rm tot}_\omega-\pi^{\rm lead}_\omega\bigr). \end{split} \end{equation} The bracket is nonnegative (\cref{lem:oct24:invariant-background}(v), \cref{lem:orbit-coupon}(iv)), and $\phi_\omega$ is a polynomial with nonnegative coefficients in the auxiliary prices, each monomial a product of one auxiliary price of each record of $\omega$, as (CP5) requires. \item \emph{Uniform cost.} Without the invariant split and the coupon, that is with $\kappa_b=\kappa_H$ and $M^{\rm inv}=0$, \begin{equation}\label{eq:oct24:envelope-cost} \phi_\omega=\bigl(\kappa_He^{U_0}+MR_{\rm err}\bigr)\pi^{\rm arm}_\omega +B\bigl(\pi^{\rm tot}_\omega-\pi^{\rm lead}_\omega\bigr). \end{equation} \item \emph{Invariant background.} The main term of the outside energy obeys the split \begin{equation}\label{eq:envelope-background} \kappa_He^{U_0}-(\kappa_H-\kappa_b)e^{t\Uinv}, \end{equation} for every class, with the assigned prices of \cref{lem:oct24:invariant-background}(v). The class bound is nondecreasing in $\kappa_H$, $\kappa_b$, $M$, $R_{\rm err}$, $B$ and $U_0$; $\Uinv$ is the assigned price, not an upper bound for one, and $M^{\rm inv}$ and $\delta_{\rm s}$, which enter with a minus sign, are a lower bound and the saving computed from the same tag prices as $R_{\rm err}$. \item \emph{Admissibility and robustness.} The couplings of the expansions of the $[D_\omega]_\omega$ (tensor products of $M_{ab},P_{12},P_{01},\Jproj$, placed by the records) and their orbit averages are admissible positive laws (\cref{def:admissible}), independent of the indices, with no sharp bound applied to them. The bounds (i)--(iii) are robust (\cref{def:robust}), uniformly in $(X_F,X_E)$, in $\mathcal C$ and in the envelope family ranging over a finite set. \item \emph{Witnesses.} The following envelopes pass the tests of \cref{lem:oct24:mask-schur} in exact rational arithmetic at $Q_3$; their caps include their frame factors, $\Gamma_F^n\Gamma_E^m$ of \cref{lem:oct24:mask-schur}(b) for the matrix envelopes in (a)--(b) and the E-type families in (d), and the weighted-frame bound for the diagonal mask envelopes in (b)--(c). \begin{enumerate}[label=(\alph*)] \item The singleton-block matrix envelopes of the pairs FF and FE. \item The higher envelopes of the classes with $n\ge1$, $n+m\in\{4,6\}$, other than $(6,0)$: the singleton-block matrix envelopes F1E3 and F1E5 (one fold factor), F2E2 (two-fold), F3E1 (three-fold) and F4E0 (four-fold); and the diagonal mask envelopes F2E4, F3E3, F4E2, F5E1, which use the extra averages of \cref{lem:reflection-averaging}(f) on the invariant background. \item The diagonal mask envelope F6E0. \item The E-type envelopes: the diagonal envelopes of the crossed and of the aligned matching pairs, with the averages of \cref{lem:reflection-averaging}(g), and the families E4, E6, one diagonal envelope for each group of words. \end{enumerate} \end{enumerate} The $o(1)$ consists of energy errors and large-product remainders. \end{theorem} The certified envelopes are the sixteen rows of \cref{tab:data:envelopes}, from the bundle \path{research/further_2026_10_25/envelopes/exact_background_pairs.json}; its rows named F0E4 and F0E6 (candidate envelopes for the classes $(0,4),(0,6)$) are not used --- those classes instead use the envelopes named E4 and E6 in the table. The proofs of the domination are the exact rational tests of \cref{lem:oct24:mask-schur} (\cref{cert:envelopes}), not the numerical optimizations that proposed the matrices. For instance the FE envelope has $\kappa_H<0.916505$, $\kappa_b<0.775465$ and $M<25.050376$: the extra reflection of the mixed pair lowers its effective cap by about $0.14$. \begin{proof} \emph{Step 1: remainders.} Let $\omega\in\mathcal C$. By \ref{it:env:N1}--\ref{it:env:N3}, $\widehat\Delta_\omega=\bigotimes_\Blk\widehat\Delta_{\omega(\Blk),\Blk}=L_\omega+\Upsilon_\omega$, where $\Upsilon_\omega$ is self-adjoint, the tensor having an even number of skew-adjoint factors, with $\|\Upsilon_\omega\|\le\upsilon_\omega:=\prod_\Blk(\ell_\Blk+\rho_\Blk)- \prod_\Blk\ell_\Blk$ \eqref{eq:oct24:star-tensor-error}; and the selected measure of $\omega$ is $\zeta_\omega=\tilde\pi^{\rm arm}_\omega[\widehat\Delta_\omega]_\omega$, $\tilde\pi^{\rm arm}_\omega$ the product of the raw-arm coefficients, so that $\pi^{\rm arm}_\omega=\tilde\pi^{\rm arm}_\omega C_X$ with $C_X=\prod_{\Blk\in X}q_\Blk^{2a}$. Since $\upsilon_\omega\operatorname{Diag}_\omega\pm[\Upsilon_\omega]_\omega\succeq_\iota0$, \ref{it:record:P5} and \ref{it:record:E1} give $|Y_{[\Upsilon_\omega]_\omega\otimes\lambda_{-X}}|\le\upsilon_\omega Y^{\Nbr}[\operatorname{Diag}_\omega] \le\upsilon_\omega(B+o(1))C_XY$, and $\tilde\pi^{\rm arm}_\omega\upsilon_\omega C_X= \pi^{\rm tot}_\omega-\pi^{\rm lead}_\omega$. \emph{Step 2: domination.} By \cref{lem:reflection-averaging}(e), $\mathcal U_\omega^*L_\omega\mathcal U_\omega$ is $\pm$ a tensor product of stars of the chart shape, with the numbers $c_p$ of \ref{it:env:N1}, \ref{it:env:N3}, and by \cref{lem:oct24:mask-schur}(a) it lies between $\pm\operatorname{Lift}(D_{(\omega)})$. Hence $\pm L_\omega\preceq D_\omega$, $[D_\omega]_\omega\pm[L_\omega]_\omega\succeq_\iota0$, and by \ref{it:record:P5}, $|Y_{[L_\omega]_\omega\otimes\lambda_{-X}}|\le Y^{\Nbr}[[D_\omega]_\omega]$. \emph{Step 3: the outside bracket, coupling by coupling.} The chart unitaries conjugate the coupling basis into itself ($\mathcal U$ by $\varphi$, $\mathcal P_{(0\,1)}$ by the transposition of the names), so $[D_\omega]_\omega=\sum_Cc(C)[C]_\omega$ with placed couplings, which are admissible probability measures (\cref{lem:oct24:pure-pair-substitute}), and $\sum_C|c(C)|=M(D_{(\omega)})$. By \cref{lem:orbit-coupon}, $Y^{\Nbr}[[D_\omega]_\omega]\le Y^{\Nbrz}[[D_\omega]_\omega]+(M(D_{(\omega)})R_{\rm err} -M_\omega e^{t\Uinv}t\delta_{\rm s}+o(1))C_XY$, with $M_\omega$ the orbit mass of $\omega$ (zero if no $h$ applies). With Steps 1 and 2, \[ |I_\omega|\le\tilde\pi^{\rm arm}_\omega\Bigl(Y^{\Nbrz}\bigl[[D_\omega]_\omega\bigr] +\bigl(M(D_{(\omega)})R_{\rm err}-M_\omega e^{t\Uinv}t\delta_{\rm s}+o(1)\bigr)C_XY\Bigr) +\bigl(B(\pi^{\rm tot}_\omega-\pi^{\rm lead}_\omega)+o(1)\pi_\omega\bigr)Y . \] The coupling mass is that of the envelope before any averaging. \emph{Step 4: averaging.} At every atom outside $X$, $\Nbr_{0,\Blk}$ is $R_5$-invariant and $\succeq_\iota0$ (\cref{lem:oct24:invariant-background}(iv)). By \ref{it:env:N4}, $\tilde\pi^{\rm arm}_{\bar\omega}=\tilde\pi^{\rm arm}_\omega$, and by \cref{lem:reflection-averaging}(e) the operators $K_\omega=D_\omega$ satisfy the hypothesis of \cref{lem:reflection-averaging}(d), with $\frac12(K_\omega+g_\omega K_\omega g_\omega^*)=\bar D_\omega$, because $g_5\operatorname{Lift}(D)g_5^*=\operatorname{Lift}(g_{5*}D)$ and $D_{(\bar\omega)}=D_{(\omega)}$. Summing Step 3 over $\mathcal C$ and applying \cref{lem:reflection-averaging}(d), the main terms become $\sum_\omega\tilde\pi^{\rm arm}_\omega Y^{\Nbrz}[[\bar D_\omega]_\omega]$. The operator $\bar D_\omega$ is a lift, positive, annihilating every vector with a constant factor, and of norm at most its cap. \emph{(iii) and (i).} Write $\Nbr_{0,\Blk}=\Nbr^{\rm inv}_\Blk+G_\Blk$ at the middle blocks outside $X$ and expand: $\Nbrz$ outside $X$ is $\sum_ZO_Z$, where $O_Z=\bigotimes_{\Blk\in Z}G_\Blk\otimes\bigotimes_{\Blk\notin Z\cup X}\Nbr^{\rm inv}_\Blk$ and $Z$ runs over the sets of middle blocks outside $X$; write $Y^{O_Z}[\kappa]=Y_{\kappa\otimes O_Z}$. Every $O_Z$ is a product of $R_5$-invariant measures $\succeq_\iota0$, and $O_\varnothing=\bigotimes\Nbr^{\rm inv}_\Blk$ is invariant under $\mathcal G_6$. For $Z\ne\varnothing$, or for $\omega$ admitting no additional average, $\bar D_\omega\preceq\|\bar D_\omega\|I$ gives, by the general form of \ref{it:record:E2} with the outside measure $O_Z\succeq_\iota0$, $Y^{O_Z}[[\bar D_\omega]_\omega]\le\|\bar D_\omega\|Y^{O_Z}[\operatorname{Diag}_\omega]$. For $Z=\varnothing$ and $\omega$ with all fold records equal, or without fold records, \cref{lem:reflection-averaging}(f), (g) replace $\bar D_\omega$ by its additional average, whose norm is the cap $b(\omega)$ used in $\kappa_b$. Expanding $\Nbr^{\rm inv}_\Blk=\mu_\Blk+(E_{\rm add}+H)_\Blk$ in every $O_Z$, each term of $Y^{O_Z}[\operatorname{Diag}_\omega]$ is the energy of an admissible positive measure with $\mu$ outside, at most $(1+o(1))C_X$ times the product of the tag prices times $Y$ (\ref{it:record:E1}), as in the proof of \cref{lem:bracket-energy}. Summing over $Z$ and averaging over the class, the coefficient of a monomial in the invariant tags alone is the class average $\kappa_b$, and that of every other monomial is $\kappa_H$: the main terms are at most $|\mathcal C|\,\tilde\pi^{\rm arm}C_X(1+o(1))Y$ times $\kappa_H\prod_\Blk(1+v_\Blk+w_\Blk)-(\kappa_H-\kappa_b)\prod_\Blk(1+v_\Blk)$, and \cref{lem:oct24:invariant-background}(v) bounds this by \eqref{eq:envelope-background}. The monotonicity: the derivative in $\kappa_H$ is $e^{U_0}-e^{t\Uinv}\ge0$, in $\kappa_b$ it is $e^{t\Uinv}$, and the other variables enter with nonnegative coefficients. Adding the coupling terms of Step 3, averaged over the class, and the remainders of Step 1 gives \eqref{eq:envelope-class-bound}; all selections of $\mathcal C$ have the same auxiliary monomials, so the class sum may be written with the class averages. The energy errors and the large-product remainders of the finitely many applications of \ref{it:record:E1} and \cref{lem:orbit-coupon} are $o(1)$ times the monomials $\pi^{\rm arm}_\omega$, $\pi^{\rm lead}_\omega$, $\pi^{\rm tot}_\omega$, which are at most $2^{|X|}\pi_\omega$: the raw-arm and leading price of a record are at most its full skew price, and its remainder price at most $r_E(X)b^{-1}$ or $a_F(b)b^{-1/2}$ times its raw-arm price. This is (i). (ii) is the case $\kappa_b=\kappa_H$, $M^{\rm inv}=0$ of (i), which needs neither the additional averages nor \cref{lem:orbit-coupon}: by \ref{it:record:E2} with $\Nbrz\succeq_\iota0$ outside and \ref{it:record:E1}, $Y^{\Nbrz}[[\bar D_\omega]_\omega]\le\|\bar D_\omega\|(e^{U_0}+o(1))C_XY$. (iv) The couplings are those of \cref{lem:oct24:pure-pair-substitute}, placed and tensorized, and their orbit averages: positive, normalized, with uniform one-slot marginals and invariant under the translations at each prime; they are laws of field labels only, so they do not depend on the indices (O1); the only operator bounds applied to them are the brackets at $\iota$ between actual half spaces of Steps 1 and 2, with nothing conditioned (O2); all energies carry $F_A$ at every slot, so (O3) and (O4) are void. Each bound is built from finitely many applications of \ref{it:record:E1} and of \cref{lem:sharp-first}, with nonnegative coefficients, and from the exact relations \ref{it:record:P5}, \ref{it:record:E2}, \cref{lem:reflection-averaging} and the orbit decomposition; the number of applications is bounded in terms of $n+m\le6$ and the size of the coupling bases. If every structured-energy bound is inflated as in \cref{def:robust} by a factor $1+z$, the same proofs give the bounds with $e^{U_0}$, $R_{\rm err}$, $B$, the coupon and the background polynomial inflated, continuously in $z$; this is robustness (\cref{lem:record:rec}(i)). Finally, (v) follows from \cref{cert:envelopes}(b), together with the tests of \cref{lem:oct24:mask-schur}(c), (d) and the averages of \cref{lem:reflection-averaging}(d)--(g). \end{proof} \subsection{Variance savings retained inside dominating matrices} \label{subsec:class-credit} The lift of a positive envelope annihilates every vector having a constant factor at some block: it is built on the mean-zero feature spaces, which carry the stars because every record difference annihilates the constants. So its energy is a variance in the sense of \cref{lem:record:variance-interface}, and a lower bound for the energy of the product of the actual half marginals lowers the class cost. The credit must be taken with a fraction at most the norm bound of the averaged envelope on the branch where it is taken; keeping a larger variance subtraction with a smaller envelope would be invalid, and so would adding the credit of a quartic envelope to the full-norm credit of the same class. \begin{lemma}[Variance credit inside a positive envelope]\label{lem:class-credit} In the setting of \cref{thm:envelopes}, let $\mathcal C'\subseteq\mathcal C$ be a set of selections, and suppose that \[ \frac1{|\mathcal C'|}\sum_{\omega\in\mathcal C'}Y[J_\omega]\ge(\bar l-o(1))\,C_XY \] (a selected-only restoration). For $\omega\in\mathcal C'$ let $c_\omega$ be the cap that the proof of \cref{thm:envelopes}(i) uses for $\omega$ on the outside monomial of $\mu$ alone, that is, the bound for the norm of the averaged envelope of $\omega$ after the averages of \cref{lem:reflection-averaging}(d)--(g) that apply to it; let $0\le c\le\min_{\mathcal C'}c_\omega$ and $0\le g\le\max(\bar l,0)$. Then (CP5) holds for $\mathcal C$ with the class bounds $\phi_\omega-cg\,\pi^{\rm arm}_\omega$ for $\omega\in\mathcal C'$ and $\phi_\omega$ for $\omega\in\mathcal C\setminus\mathcal C'$, with $\phi_\omega$ of \eqref{eq:envelope-class-bound}. In the construction, $X$ consists of distinct middle blocks of the pieces of a multiset $m$ of pieces (the letter of \cref{sec:variance} for a multiset of pieces, not the matching-record count $m$ in the class cost $C_{n,m}$; in (a)--(c) the classes are named by their degrees), the gains are those of \eqref{eq:variance:fresh} at the piece caps $C_m$ of \cref{lem:piece-caps} (\cref{cor:variance:final}), and the credited classes are: \begin{enumerate}[label=(\alph*)] \item \emph{Aligned fold pairs.} In the class $(2,0)$ with the envelope FF, $\mathcal C'=\{(F_1,F_1),(F_2,F_2)\}$, $c=\kappa_{FF}:=\kappa_H(\mathrm{FF})=\kappa_b(\mathrm{FF})$ and $g=g_F(m)$. At one fold copy the coefficient of the outside background law $\Nbrz$ in the fold gain $g_F(m)$ is zero, and no term pooled over later pieces is added. The crossed fold pairs get no credit. \item \emph{Aligned matching pairs.} In the class of the aligned pairs $\{(E_0,E_0),(E_1,E_1)\}$ with the envelope EE aligned, $\mathcal C'=\mathcal C$, $c=\kappa^{\rm al}_b:=\kappa_b(\text{EE aligned})$ and $g=g^{\rm sel}_E(m)$, the selected-only aligned gain, without the $E_{\rm add}$ background and the pool term; the residual coefficient of the $\mu$ branch is $\kappa^{\rm al}_b(1-g)\ge0$. The crossed pairs get no credit. \item \emph{Quartic classes.} In the classes $(4,0)$ and $(0,4)$, which keep their envelopes F4E0 and E4, $\mathcal C'$ is the set of aligned words (all fold records equal, respectively all matching records equal; weight $2^{1-4}$), $c$ is the cap of the envelope on these words, $\kappa_{4,F}:=\kappa_H(\mathrm{F4E0})$ and $\kappa_{4,E}$ the invariant cap of the aligned group of E4, and $g=g^{\rm sel}_T(m)$, $T\in\{F,E\}$. A quartic class whose envelope is discarded would instead keep the full-norm credit, through $-\prod_\Blk\gamma_\Blk\bigotimes_\Blk(I-\Jproj_\Blk)\preceq\bigotimes_\Blk\Delta_\Blk\preceq \prod_\Blk\gamma_\Blk\bigotimes_\Blk(I-\Jproj_\Blk)$, where $\Jproj_\Blk$ is the projection onto constants in the actual half space at $\Blk$, for the centred differences $\Delta_\Blk$ of norms $\gamma_\Blk$ (\cref{lem:record:variance-interface}); the two alternatives are never added. In the construction neither quartic envelope is discarded. \item No other envelope class receives a variance credit; in particular no class of degree six does. \end{enumerate} \emph{Gates.} Every credit satisfies $0\le cg0$ the hypothesis gives $\sum_{\mathcal C'}Y[J_\omega]\ge|\mathcal C'|(\bar l-o(1))C_XY$; if $\bar l\le0$ use $Y[J_\omega]\ge0$ (\ref{it:record:E2}, the cut operator of $J_\omega$ being a projection). In both cases $c\sum_{\mathcal C'}Y[J_\omega]\ge|\mathcal C'|(cg-o(1))C_XY$, and $\pi^{\rm arm}_\omega=\tilde\pi^{\rm arm}C_X$. The bound is robust, uniformly in the classes (\cref{lem:record:rec}(i)): it adds to the robust bound of \cref{thm:envelopes}(i) the exact relation \ref{it:record:E2} and subtracts $c$ times the lower bound of the hypothesis, which is robust in the applications below (\cref{rem:variance:robust}). (a) The aligned assignments $(F_j,F_j)$ on $X$ satisfy \cref{lem:var-gain}(a) with $C=C_m$ and $\bar l=b_F(m)$, and $g_F(m)=[b_F(m)-R_*]_+\le\max(\bar l,0)$ (\cref{cor:var-classes}(i), \cref{cor:variance:final}(ii)). The FF envelope has $\kappa_b=\kappa_H$, so its cap on every branch is $\kappa_{FF}$, the largest admissible fraction. (b) The aligned matching class consists of its own partners, and its two selections have the same coefficient. The two aligned assignments together satisfy \cref{lem:var-gain}(a) with $\bar l=b_E(m)$, and $g^{\rm sel}_E(m)=[b_E(m)-R_*]_+$ (\cref{cor:var-classes}(ii)). On the $\mu$ branch the full average of \cref{lem:reflection-averaging}(g) applies, so $c_\omega=\kappa^{\rm al}_b$ for both selections; the background and pool terms of \cref{prop:background-variance} belong to other outside monomials and are not used here, so this credit does not reuse the invariant background discount. (c) The aligned words of the class satisfy \cref{lem:var-gain}(a) with the selected-only restorations (\cref{cor:variance:final}(iii)); on the $\mu$ branch their caps are $\kappa_{4,F}$ (the F4E0 envelope has $\kappa_b=\kappa_H$) and the invariant cap of the aligned group of E4 (\cref{lem:reflection-averaging}(g)). For the alternative, a tensor of centred differences of norms $\gamma_\Blk$ satisfies the displayed order, its factors being self-adjoint or skew-adjoint with an even number of skew ones, and \cref{lem:record:variance-interface}(iii) credits it at the full prices; it replaces, and is never added to, the envelope bound of the class. (d) The crossed classes are not credited: the lower bounds of \cref{lem:record:paired-e-joint} concern only the two aligned matching words, all $E_0$ and all $E_1$, taken together, so no lower bound for the product energies of a crossed class is available, and these classes are priced by the background bound of \cref{thm:envelopes}(iii) alone. Degree six carries no variance credit in the closing (\cref{cor:variance:final}). \emph{Gates.} By \cref{lem:oct24:invariant-background}(v), $U_0\ge t\Uinv$, and by \cref{lem:orbit-coupon}(iv), $MR_{\rm err}\ge M^{\rm inv}e^{t\Uinv}t\delta_{\rm s}$; so \[ C_{n,m}=\kappa_be^{t\Uinv}+\kappa_H\bigl(e^{U_0}-e^{t\Uinv}\bigr) +\bigl(MR_{\rm err}-M^{\rm inv}e^{t\Uinv}t\delta_{\rm s}\bigr)\ge\kappa_be^{t\Uinv}. \] The gains are in $[0,1)$ (\cref{cert:variance:fresh}) and $e^{t\Uinv}>1$. In (a), (b) and for F4E0, $c=\kappa_b$, so $cg<\kappa_b0.4817590234$ and $\kappa_{4,E}<0.6667$ (\cref{tab:data:envelopes}) and $e^{t\Uinv}>2.33$ (since $t\Uinv>0.84688$, at the opening of this section), $\kappa_b(\mathrm{E4})e^{t\Uinv}>1.122>\kappa_{4,E}>cg$. Also, the credited selections of a class form the fraction $p$ ($\frac12$, $1$, $\frac18$, $\frac18$) of its selections and $pc\le\kappa_b$, the class average of caps that are at least $c$ on the credited words, so the credit averaged over the class, $pcg$, is below $\kappa_b\le C_{n,m}$ as well. These gates are proved here and are not asserted by the certificate; the caps $c$ are fixed certified numbers, and under the inflation of \cref{def:robust} the coefficient $C_{n,m}$, a bound of the second kind of \cref{lem:record:rec}(i), only grows while the gain, a robust lower bound, only shrinks, so the gates need no margin. \end{proof} \subsection{Sixteen classes and their savings}\label{subsec:envelope-costs} This corollary is the final form of (CP5) used in the closing. A class $(n,m)$, also written $F_nE_m$, consists of the selections with $n$ skew fold changes and $m$ skew matching changes; there are sixteen such classes. For each it gives the class bound, says where a variance saving from the preceding subsection is credited, and defines the saving of the class. \begin{corollary}[The class bounds of the construction]\label{cor:envelope-costs} Let $U_0$, $R_{\rm err}$, $B$, $\Uinv$, $\delta_{\rm s}$ and the auxiliary totals be the certified quantities of \cref{def:closing-quantities} at the exponent $a$. For each class below, (CP5) holds with the class bound \eqref{eq:envelope-class-bound} of the stated envelope, credited by \cref{lem:class-credit} where stated; before any such credit, the class has the base cost \[ C_{n,m}=\kappa_He^{U_0}-(\kappa_H-\kappa_b)e^{t\Uinv}+M_{n,m}R_{\rm err} -M^{\rm inv}_{n,m}e^{t\Uinv}t\delta_{\rm s} \] per raw-arm monomial, plus the remainder polynomial, in the form of \cref{lem:record:record-expansion}(v), with the numbers $\kappa_H$, $\kappa_b$, $M_{n,m}$, $M^{\rm inv}_{n,m}$ of its envelope. For a credited selection, \cref{lem:class-credit} subtracts in addition $cg\pi^{\rm arm}_\omega$ from its class bound. \begin{enumerate}[label=(\alph*)] \item $n\ge1$, $n+m\in\{4,6\}$, the class $\Omega(X_F,X_E)$: $(1,3)$ F1E3, $(2,2)$ F2E2, $(3,1)$ F3E1, $(4,0)$ F4E0 (credited by \cref{lem:class-credit}(c)), $(1,5)$ F1E5, $(2,4)$ F2E4, $(3,3)$ F3E3, $(4,2)$ F4E2, $(5,1)$ F5E1, $(6,0)$ F6E0. \item $(2,0)$: FF; the aligned pairs are credited (\cref{lem:class-credit}(a)). \item $(1,1)$: FE, on a union of two partner pairs. \item $(0,2)$: the aligned pairs with EE aligned (credited, \cref{lem:class-credit}(b)) and the crossed pairs with EE crossed, each of the two classes being assigned one half of the coefficient of the matching-pair monomial, so that together they count it once. \item $(0,4)$, $(0,6)$: E4 (credited on its aligned words) and E6. \end{enumerate} The gates are: $C_{n,m}\ge\kappa_be^{t\Uinv}>0$; every coupon is at most $M_{n,m}R_{\rm err}$; $cg1$}{m>1}}\label{sec:matching-mean} \paragraph{What this section proves and how to read it.} This section proves (CP6) and (CP7): it constructs positive laws $M_{{\rm L},\Blk},M_{{\rm R},\Blk}$ dominating $\nu_\Blk$ at $\iota$ (called \emph{matching envelopes} in (CP6); they are unrelated to the matching records $E_0,E_1$---in prose we call them \emph{dominators for $\nu$}), with total price $T$ entering $J=Be^T(R_I/2)^6$ through $e^T$, and it proves the mean energies exceed $mY$ with $m>1$ (a lower bound \emph{added} to the energy, hence $(1-m)/64<0$ in $\Theta$, unlike the subtracted savings $D$). The \emph{side functions} below collect the diagonal weights; only their final values are used, and the long list of intermediate constants in \cref{def:side-function} that no estimate uses can be skipped---the theorem statements cite only the assembled $T$ and $m$. Reading-order note: $T$ includes upper-range prices proved in \cref{sec:upper-comparison}; the per-block dominator construction here is independent, the total $T$ is assembled in \cref{sec:closing}. Inputs: \cref{sec:middle-frame}. Outputs: (CP6),(CP7) with baseline $T<0.60760$, $m>1.58994$. \begin{itemize} \item For every atom $\Blk$ it constructs two positive measures $M_{{\rm L},\Blk}$ and $M_{{\rm R},\Blk}$, the \emph{matching envelopes}. The comparison law sits in a positive semidefinite $2\times2$ block $\bigl(\begin{smallmatrix}M_{{\rm L},\Blk}&\nu_\Blk\\ \nu_\Blk^*&M_{{\rm R},\Blk}\end{smallmatrix}\bigr)\succeq_\iota0$ at the reserved cut, and $M_{s,\Blk}-\Nbr_\Blk$ is a positive reserved-diagonal measure. For each $s\in\{{\rm L},{\rm R}\}$, the sum over atoms $\sum_\Blk\operatorname{price}(M_{s,\Blk}-\Nbr_\Blk)$ is at most the matching exponent $T$ of the matching term $J=Be^T(R_I/2)^6$ (\cref{prop:record:matching}). \item The proof of \cref{thm:comparison} uses the envelopes twice. Through the index-support lemma (\cref{lem:record:common-mean}) it compares the signed index form $J_\nu$ with $Y_\nu$, up to the excess of the random-inclusion energies $V_s$ of the envelopes over their mean energies $e_s$ (\cref{eq:record:cm-selected}); through \cref{lem:envelope-energy} it bounds $V_s$ by $2^6J$. The mean energies are bounded below in \cref{subsec:record:positive_means}; this is the mean credit $m$ of $\Theta$ (\cref{prop:record:mean-credit}, \eqref{eq:mean-credit}). \item The closing (\cref{cert:closing}) evaluates $T$ and $m$. \end{itemize} Every record change of the comparison law except the two two-layer fold records $F_1,F_2$ of a middle block already has such a bracket from its norm envelopes (\cref{def:record:comparison-law}). For the matching records the envelopes use chosen diagonals, which dominate the norm envelopes and are paid by the same prices. For $F_1,F_2$ the norm envelopes would enter $T$ with the full fold norm price, which is too large for $\Theta<1$, and the bracket is built directly (\cref{subsec:record:direct_gram}). The reference record and its signed comparison record are bounded jointly by a positive $2\times2$ Gram at $\iota$, whose diagonal shifts are multiples of the record's own one-layer companion. The dominator $\Nbr$ already contains that companion once, with coefficient $v_{\rm D}$ (\cref{lem:record:gram}). The joint Gram needs a diagonal of coefficient about $2.39\,w_{\rm D}$ on each side (the signed coefficient $\bar H_Xd_\tlaw$), and only the excess $k_s=w_{\rm D}d_s-v_{\rm D}$ is priced. The copy of the companion already present in $\Nbr$ is not counted again in that diagonal. Each chosen side is an auxiliary side, given by a certified formula, plus a nonnegative rounded increment, and is at least the signed Gram coefficient $\bar H_Xd_\tlaw$. So only nonnegative increments are added to the auxiliary price (\cref{subsec:signed-sides}). The envelopes and $T$ are assembled in \cref{subsec:matching-envelopes}, the common mean of the selected law in \cref{subsec:cm-selected}, and the mean credit in \cref{subsec:record:positive_means}. \subsection{A joint \texorpdfstring{$2\times2$}{2 x 2} block for reference and comparison records}\label{subsec:record:direct_gram} The matching bracket uses the reference and the signed comparison record jointly. Its leading part is a small matrix in the four actual features $V_0,A_1/r,A_2/r,A_3/r$; it does not require a second calculation of their individual spectra. We first isolate that matrix calculation, then state the arithmetic side function used to price the resulting diagonals. \begin{lemma}[The leading Gram]\label{lem:record:direct-gram} Let $\mathcal H$ be a Hilbert space and let $V,A_1,A_2,A_3\colon H_0\to\mathcal H$ satisfy $\|(V,A_1/r,A_2/r,A_3/r)\|^2\le\Gamma$, where $r>0$. For $\xi\in\R^3$ put $A_\xi=\sum_i\xi_iA_i$ and $\mathbf e=(1,0,0)$. For $u,v\in\R^3$ define \[ L_{\rm old}=-(A_{\mathbf e}V^*+VA_{\mathbf e}^*),\qquad L_{u,v}=A_uV^*+VA_v^*,\qquad G(u,v)=\begin{pmatrix}L_{\rm old}&L_{u,v}\\L_{u,v}^*&L_{\rm old}\end{pmatrix}. \] For $\tside>0$ let \[ \Upsilon_{\tside}(u,v)= \begin{pmatrix}-\mathbf e/\tside&u\\v&-\tside\mathbf e\end{pmatrix},\qquad s(\tside;u,v)=\|\Upsilon_{\tside}(u,v)\|. \] This is a real $6\times2$ matrix, and \begin{gather*} s(\tside;u,v)^2=\lambda_{\max} \begin{pmatrix}\tside^{-2}+\|v\|^2&-u_1/\tside-\tside v_1\\ -u_1/\tside-\tside v_1&\tside^2+\|u\|^2\end{pmatrix},\\ G(u,v)\succeq-r\Gamma s(\tside;u,v) \operatorname{diag}(\tside I,\tside^{-1}I). \end{gather*} For the signed arm vector $\mathbf a_\tlaw=(\tlaw,1,1-\tlaw)$, put $u_\tlaw=\mathbf a_\tlaw-\mathbf e$ and $v_\tlaw=-\mathbf a_\tlaw-\mathbf e$. Then \[ L_{u_\tlaw,v_\tlaw}=L_{\rm old} +A_{\mathbf a_\tlaw}V^*-VA_{\mathbf a_\tlaw}^*,\qquad G(u_\tlaw,v_\tlaw)\succeq-r\Gamma s_\tlaw I, \] where \[ s_\tlaw=\bigl(4-2\tlaw+2\tlaw^2+2\sqrt{1+\tlaw^2}\bigr)^{1/2}, \qquad s_0=\sqrt6. \] The statement holds directly in the actual half-marginal space; the adjoints and the frame bound are always those of $\mathcal H$. \end{lemma} \begin{proof} Let $\Sigma=(V,A_1/r,A_2/r,A_3/r)$ and $\mathbf S=\operatorname{diag}(\Sigma,\Sigma)$. In each copy of $H_0^4$ separate the centre coordinate $V$ from the three arm coordinates. After conjugating $G(u,v)$ by $\Delta_{\tside}^{-1/2}$, where $\Delta_{\tside}=\operatorname{diag}(\tside I,\tside^{-1}I)$, its coefficient matrix in these eight features, ordered with both centres first, is \[ \mathbf M=\begin{pmatrix}0&\Upsilon_{\tside}^{\mathsf T}\\ \Upsilon_{\tside}&0\end{pmatrix}. \] Indeed the old diagonal stars acquire the coefficients $-\mathbf e/\tside$ and $-\tside\mathbf e$, while the off-diagonal arms retain $u,v$. Thus the conjugated operator is $r\mathbf S(\mathbf M\otimes I)\mathbf S^*$, with the same coordinate permutation in $\mathbf S$. The least eigenvalue of $\mathbf M$ is $-\|\Upsilon_{\tside}\|$, so it is at least $-r s(\tside;u,v)\mathbf S\mathbf S^*\succeq-r\Gamma s(\tside;u,v)I$. Conjugating back proves the order. The displayed $2\times2$ matrix is $\Upsilon_{\tside}^{\mathsf T}\Upsilon_{\tside}$. At the signed point, linearity of $A_\xi$ gives the identity for $L_{u_\tlaw,v_\tlaw}$, and at $\tside=1$ the last matrix is \[ \begin{pmatrix}4+2\tlaw^2&2\\2&4-4\tlaw+2\tlaw^2\end{pmatrix}. \] Its largest eigenvalue is $4-2\tlaw+2\tlaw^2+2\sqrt{1+\tlaw^2}$. \end{proof} In the application $\mathcal H=L^2(m_0)$ and the features are those of \cref{lem:actual-features}, with $V=V_0$ and $\Gamma=\Gamma_A$. The reference contributes $L_{\rm old}$ on the diagonal; the signed law contributes its old leading part plus its skew leading difference off the diagonal (\cref{lem:old-f-law}(f), \cref{prop:signed-bounds}(c)). This is why the Gram gives a joint bracket and not only a norm bound for the change. At $\tlaw=127/500$, $s_\tlaw=2.38422727\ldots$, compared with $\sqrt6=2.4494897\ldots$ at the mirror point. Adding the two remainders gives the actual coefficient \[ d_\tlaw=s_\tlaw\Gamma_A+(e_o+e_{\rm sg})r, \] which is below $2.39033202$ at $Q_3$. The block argument is \cref{prop:signed-sides} below. \paragraph{Auxiliary sides and the certified price.} The Gram in the actual space $L^2(m_0)$ is supplied by the signed law. The numerical price is stored as an auxiliary side plus a nonnegative increment to that Gram coefficient. We retain the complete arithmetic definition of the auxiliary side because it fixes this split and its outward roundings. Its parameters are inherited from a probability mixture of four sign patterns, but no law of the construction uses that mixture; no operator estimate for it is needed. In particular the coefficients below are definitions of numbers, not assertions about another comparison law. \begin{definition}[The side function]\label{def:side-function} For a prime $p\equiv3\pmod4$ with $q=1/p\le2^{-20}$, put $r=p^{-1/2}$, $Z=(1-q)(1-2q)$, $h_0=1-14q$ and $e_0=2q/((1-3q)(1-4q))$, as in \cref{subsec:middle-records:notation}. Fix \[ (w_{++},w_{+-},w_{-+},w_{--})=(5803723,2409463,1786814,0)/10^7, \] \[ (\bar b,\bar d,\bar f)=(b_0,d_0,f_0)=(.6426372,.5181074,.1607446),\qquad \tside=31/32, \] where $\bar b=\sum_{(\beta,\delta)\in\{\pm1\}^2}\beta w_{\beta\delta}$, $\bar d=\sum_{(\beta,\delta)\in\{\pm1\}^2}\delta w_{\beta\delta}$ and $\bar f=\sum_{(\beta,\delta)\in\{\pm1\}^2}\beta\delta w_{\beta\delta}$. Set $u=(-\bar b,1,\bar b)$, $v=(-1,-\bar d,-\bar d)$, $s(\tside)=s(\tside;u,v)$ as in \cref{lem:record:direct-gram}, and \begin{gather*} \gamma=\left(1+\frac{q(1+2r)}{1-2q}\right)^{1/2},\qquad c_{\rm lead}=\gamma(\|u\|_2+\|v\|_2),\\ F_{\rm frame}=\frac{2+|\bar b+1|}{1-q} +\frac{|1-\bar d|q}{(1-q)(1-2q)} +\frac{2|\bar b-\bar d|q^2}{(1-q)(1-2q)} +\frac{|2-\bar b+\bar d|r}{1-q},\\ \zeta_{++}=\frac{6q^2}{(1-4q)(1-5q)},\qquad \zeta_{+-}=\frac{4q}{(1-4q)(1-5q)},\\ \zeta_{-+}=\frac{4q}{(1-4q)(1-5q)(1-7q)},\qquad \zeta_{--}=\frac{8q}{(1-4q)(1-5q)(1-7q)},\\ C_{\rm old}=\frac{19}{Zh_0},\qquad C_{\rm ns}=2|\bar b|+1+2|\bar d|+4|\bar f|,\qquad n_*=\frac{1+8r+(18/Z+144)q}{h_0},\\ C_z=\frac{n_*}q\sum w_{\beta\delta}\zeta_{\beta\delta},\qquad C_{\rm new}=\frac{2C_{\rm ns}/Z+144+|\bar b-\bar d|}{h_0}+C_z,\\ k_{\rm raw}=\frac{rc_{\rm lead}}{h_0}+qC_{\rm new},\qquad \eta_1=\frac{(4w_{++}+6w_{+-}+4w_{-+}+8w_{--})q}{h_0},\\ \rho_1=\frac{k_{\rm raw}+\eta_1^2}{1-\eta_1},\qquad \eta_\star=\frac{e_0+\eta_1}{1-\eta_1},\qquad \phi_2=\frac{\eta_\star}{1-\rho_1},\qquad K_\infty=\frac4{h_0^{1/2}(1-\eta_1)},\\ \phi_\infty=\eta_\star+K_\infty\phi_2,\qquad C_{\rm rep}=\frac{2\phi_\infty}q\Bigl(k_{\rm raw}+\frac{14q}{h_0}\Bigr), \qquad C'=C_{\rm new}+C_{\rm rep}. \end{gather*} With these numbers define \begin{gather*} c_{\rm com}=\frac{rF_{\rm frame}}{h_0} +r\Bigl(C_{\rm old}+C'+\frac{2e_0^2}q\Bigr),\\ d^m_{\rm L}=\frac{\gamma s(\tside)\tside/h_0+c_{\rm com}}{1-e_0},\qquad d^m_{\rm R}=\frac{\gamma s(\tside)\tside^{-1}/h_0+c_{\rm com}}{1-e_0},\\ k_0=\frac{2\gamma/h_0+r(C_{\rm old}+14/h_0+2e_0/q+e_0^2/q)}{1-e_0},\\ k_1=\frac{c_{\rm lead}/h_0+r(C'+14/h_0+2e_0/q+e_0^2/q)}{1-e_0},\\ \bar k=\max(k_0,k_1). \end{gather*} For a middle piece starting at $X$, evaluate at $q_X=1/X$ and $r_X=1/\lfloor\sqrt X\rfloor\ge X^{-1/2}$, and put $n_X=\lfloor L_{\rm loc}/\log_-X\rfloor$, $L_{\rm loc}=585$ (\cref{lem:record:local-domain}). The \emph{auxiliary sides} are \[ d^{\rm aux}_s(X)=e^{n_Xe_0(X)} \max\bigl(d^m_s(X),\,2\bar k(X)^2r_X\bigr),\qquad s\in\{{\rm L},{\rm R}\}. \] Every coefficient is evaluated as follows: the displayed expression, exactly as written as a function of the independent variables $(q,r)$ in the nondecreasing form of \cref{lem:majorant} (each remainder $qc$ written as $r(rc)$), is evaluated at $(q_X,r_X)$; no coefficient is used in a different $(q,r)$ form. In particular a remainder evaluated at $q_X$ is never divided by the larger value $r_X$. The $33$ values and their gates, including $\eta_1<1$, $\rho_1<1$ and $2\phi_\infty<1$, are those of \cref{tab:data:sides,cert:record:matching}. \end{definition} At this auxiliary point $s(31/32)=2.0778741\ldots$, $s\tside=2.0129405\ldots$ and $s/\tside=2.1449023\ldots$. The chosen physical sides below are at least the signed Gram coefficient, regardless of these smaller auxiliary values. For the block argument, recall that $\nu_F$ is the uniform law of a half $(x_0,x_1,x_2)$ with distinct labels and $x_0\to x_2$. The reference record has density $K_0=\Psi_0/z_0$ relative to $\nu_F\otimes\nu_F$, where $\Psi_0=I_\times(1+\mathsf A)(1+\mathsf B)$ and both half marginals are $m_0=g_0\nu_F$. Here $h_0\le z_0\le1$ and $|g_0-1|\le e_0$ (\cref{lem:old-f-law}(a)); all Markov adjoints in the next lemma are in $L^2(m_0)$. \begin{lemma}[Unequal sides]\label{lem:record:asymmetric-gram} Let $\Blk$ be a middle block of a piece starting at $X$, with least prime $b$, $r_b=b^{-1/2}$ and at most $n_X=\lfloor L_{\rm loc}/\log_-X\rfloor$ primes. Let $\Pi'_{F_1,\Blk}$ be a record placed by $F_1$ whose kernel is a finite real combination \[ K'_\Blk=\sum_{c\in I}\alpha_c\bigotimes_{p\in\Blk}K'_{c,p},\qquad \sum_{c\in I}\alpha_c=1, \] of products of probability couplings $K'_{c,p}$ with both half marginals $m_0$ (a single product is the case $|I|=1$); write $T'_{c,p}$ for their Markov operators on $L^2(m_0)$ and $T'_p=\sum_c\alpha_cT'_{c,p}$. \begin{enumerate}[label=(\alph*)] \item \emph{Enlargement.} If the block cut matrix of (b) is $\succeq_\iota0$ with sides $d_{\rm L},d_{\rm R}$, it is so with any sides $d'_{\rm L}\ge d_{\rm L}$, $d'_{\rm R}\ge d_{\rm R}$. \item \emph{Block extension.} Suppose that, for nonnegative functions $c_{\rm L},c_{\rm R}$ of $(q,r)$ that are nondecreasing in $(q,r)$ and a number $c_{\ge2}(X)\ge0$, \begin{itemize} \item at every prime $p\in\Blk$, on $L^2(m_0)^2$, $\bigl(\begin{smallmatrix}T_{\rm old}+r_pc_{\rm L}I&T'_p\\ T'^*_p&T_{\rm old}+r_pc_{\rm R}I\end{smallmatrix}\bigr)\succeq0$, with $c_s=c_s(1/p,p^{-1/2})$ and $T_{\rm old}$ the Markov operator of $K_0$; \item on every exact support $S\subseteq\Blk$ of at least two primes, the restrictions to the sector $\mathcal H_S$ of the old block operator $\bigotimes_pT_{{\rm old},p}$ and of the new one $\sum_c\alpha_c\bigotimes_pT'_{c,p}$ have norms summing to at most $c_{\ge2}(X)r_Xr_b$. \end{itemize} Then, as cut matrices at $\iota$ of measures on the labels of $\Blk$, \[ \begin{pmatrix}\Pi_{F_1,\Blk}+r_bd_{\rm L}D^1_\Blk&\Pi'_{F_1,\Blk}\\ \Pi'^{\,*}_{F_1,\Blk}&\Pi_{F_1,\Blk}+r_bd_{\rm R}D^1_\Blk \end{pmatrix}\succeq_\iota0 \qquad\text{for}\quad d_s\ge H_\Blk\max\bigl(c_s(X),c_{\ge2}(X)r_X\bigr), \] where $H_\Blk$ is any bound for the density of $m_{0,\Blk}=\bigotimes_pm_{0,p}$ relative to $\nu_F^{\otimes\Blk}$, for instance $e^{n_Xe_0(X)}$, or $\bar H_X=(1-n_Xe_0(X))^{-1}$ if $n_Xe_0(X)<1$; and $D^1_\Blk$ is the diagonal copy at $\iota$ of the product law $\nu_F^{\otimes\Blk}$ placed by $F_1$, the normalized one-layer companion of $F_1$ in $\widetilde\mu_\Blk$. \item Let $\varsigma(x)=(-x_2,-x_1,-x_0)$ and $\Phi(x,y)=(\varsigma y,\varsigma x)$. Then $\varsigma$ preserves $\nu_F$ and $g_0$, $\Phi$ preserves $K_0$, and $\Phi$ maps the edges $x_0\to y_2$, $y_0\to x_2$, $x_1\to y_0$, $x_0\to y_1$ to $x_0\to y_2$, $y_0\to x_2$, $x_2\to y_1$, $x_1\to y_2$. If the comparison record of $F_2$ is the reflected transpose of that of $F_1$, $K'_{2,c,p}(x,y)=K'_{c,p}(\varsigma y,\varsigma x)$ for every component and every prime, then (b) holds for $F_2$ with $d_{\rm L}$ and $d_{\rm R}$ interchanged. \end{enumerate} Consequently, if the \emph{side gates} $k_s:=w_{\rm D}d_s-v_{\rm D}\ge0$, $s\in\{{\rm L},{\rm R}\}$, hold in the piece, the two fold records of a block cost $k_{\rm L}+k_{\rm R}$ per unit $r_b^2$ on each side. \end{lemma} \begin{proof} (a) The difference of the two cut matrices is the diagonal $\operatorname{diag}((d'_{\rm L}-d_{\rm L})r_bD^1_\Blk,(d'_{\rm R}-d_{\rm R})r_bD^1_\Blk)$, a positive reserved-diagonal measure, which is $\succeq_\iota0$ (\ref{it:record:E3}). (b) The old block operator is $\bigotimes_pT_{{\rm old},p}$ and the new one is the combination $T'_\Blk=\sum_c\alpha_c\bigotimes_pT'_{c,p}$; every prime factor fixes the constants of $m_0$ on both sides, because all these couplings have the actual marginal $m_0$ on both sides. By \cref{lem:sector}(a) and \cref{rem:signed-mixture-sectors} both preserve the orthogonal sectors $\mathcal H_S$ on which the factors in a set $S$ of primes are mean-zero and the others constant; the old one is $\bigotimes_{p\in S}(T_{{\rm old},p}-\Jproj)$ there, and the new one is $T'_p-\Jproj$ at the one coordinate $p$ if $S=\{p\}$. So the block Gram is the orthogonal sum of its restrictions to the sectors (\cref{lem:sector}(a)), and it suffices to treat each sector with the shifts $\sigma_s=r_b\max(c_s(X),c_{\ge2}(X)r_X)$. On $\mathcal H_\emptyset$ it is $\bigl(\begin{smallmatrix}1+\sigma_{\rm L}&1\\1&1+\sigma_{\rm R} \end{smallmatrix}\bigr)\succeq0$, as $\sum_c\alpha_c=1$. On $S=\{p\}$ it is the restriction of the prime Gram at $p$, which holds with the shifts $r_pc_s(1/p,p^{-1/2})\le r_bc_s(X)\le\sigma_s$, by the monotonicity of $c_s$, as $p\ge b\ge X$ and $r_X\ge X^{-1/2}$; larger shifts preserve it. For $|S|\ge2$ let $O$ and $N$ be the restrictions of the old and new operators; $O$ is self-adjoint, $\|O\|+\|N\|\le c_{\ge2}(X)r_Xr_b\le\sigma_s$, and $\bigl(\begin{smallmatrix}O+\sigma_{\rm L}&N\\N^*&O+\sigma_{\rm R}\end{smallmatrix}\bigr) \succeq\bigl(\begin{smallmatrix}(\sigma_{\rm L}-\|O\|)I&N\\N^*&(\sigma_{\rm R}-\|O\|)I \end{smallmatrix}\bigr)\succeq0$, since $\sigma_s-\|O\|\ge\|N\|$. This gives the block Gram on $L^2(m_{0,\Blk})^2$ with the shifts $\sigma_s$ times $I$. In measure form, the cut forms at $\iota$ of $\Pi_{F_1,\Blk}$ and $\Pi'_{F_1,\Blk}$ at real half-functions are the forms of $T_{{\rm old},\Blk}$ and $T'_\Blk$ on $L^2(m_{0,\Blk})$, and that of the identity is the cut form of the diagonal law $\operatorname{Diag}_\iota(m^{F_1}_{0,\Blk})$ of the actual half marginal placed by $F_1$. Its density with respect to $D^1_\Blk$ is $\prod_{p\in\Blk}g_0(x_p)\le H_\Blk$; for the two examples, $g_0\le1+e_0(X)$ at every prime of the block (\cref{lem:old-f-law}(a)), and the block has at most $n_X$ primes, so the density is at most $(1+e_0(X))^{n_X}\le e^{n_Xe_0(X)}\le \bar H_X$. Replacing $\operatorname{Diag}_\iota(m^{F_1}_{0,\Blk})$ by $H_\Blk D^1_\Blk$ therefore adds a positive reserved-diagonal measure, which is $\succeq_\iota0$ (\ref{it:record:E3}). (c) $\varsigma$ is an involution preserving $\nu_F$ (\cref{subsec:middle-records:notation}) and $g_0$ (\cref{lem:old-f-law}(a)). Writing $(x',y')=\Phi(x,y)$, a relation $s\to t$ between labels becomes $-t\to-s$; this gives the edge table, and in particular $x_0\to y_2$ and $y_0\to x_2$ are fixed, so $K_0\circ\Phi=K_0$. The added edges of $F_1$ go to those of $F_2$ (\cref{cert:record:middle-geometry}). With $(\mathcal U\varphi)(x)=\varphi(\varsigma x)$, unitary on $L^2(\nu_F)$ and on $L^2(m_0)$, the hypothesis reads $T'_{2,c,p}=\mathcal UT'^{\,*}_{c,p}\mathcal U^*$ for every component, and $\mathcal UT_{\rm old}\mathcal U^*=T_{\rm old}$. Exchange the two copies in the prime Gram of (b) and conjugate by $\operatorname{diag}(\mathcal U,\mathcal U)$: this is the prime Gram of the $F_2$ record with $c_{\rm L}$ and $c_{\rm R}$ interchanged, the shifts being multiples of the identity. On the block, $\bigotimes_p\mathcal U$ maps every sector $\mathcal H_S$ onto itself, so the bound on the sectors of at least two primes is carried over unchanged, and the density of $m_{0,\Blk}$ is $\varsigma$-invariant. So the proof of (b) applies to $F_2$ with the sides interchanged. The last assertion is the bookkeeping of the two records: by (b) and (c), the layer-zero side carries $r_bd_{\rm L}$ for $F_1$ and $r_bd_{\rm R}$ for $F_2$, the layer-one side the reverse, each record has weight $w_{\rm D}r_b$, and the bracket already contains the one-layer companion of each record with the weight $v_{\rm D}r_b^2$ (one fold copy, \cref{lem:record:gram}). \end{proof} \paragraph{The global substitution.} For a middle block $\Blk$ let $F^{(2)}_\Blk=w_{\rm D}r(\Pi_{F_1,\Blk}+\Pi_{F_2,\Blk})/\widetilde\mu_\Blk(1)$ be the reference's two two-layer fold records, with their one-layer companions $F_{{\rm fold},\Blk}=v_{\rm D}r^2(D^1_\Blk+D^2_\Blk)/\widetilde\mu_\Blk(1)$ (\cref{def:record:frame}(b), where $D^j_\Blk$ is written $\operatorname{Diag}_\iota(\Pi^{(1)}_{F_j})$), where here $\Pi_{F_j,\Blk}$ and $D^j_\Blk$ denote probability laws; the common normalizing factor is displayed explicitly, unlike the component notation of \cref{def:record:frame}(b). The law $D^2_\Blk$ is defined as $D^1_\Blk$ with $F_2$ in place of $F_1$; and put \[ \lambda_{{\rm res},\Blk}=\lambda_\Blk-F^{(2)}_\Blk,\qquad \Nbr_{{\rm res},\Blk}=\Nbr_\Blk-F^{(2)}_\Blk-F_{{\rm fold},\Blk} =\lambda_{{\rm res},\Blk}+H_\Blk . \] Outside the middle put $\lambda_{{\rm res},\Blk}=\lambda_\Blk$ and $\Nbr_{{\rm res},\Blk}=\Nbr_\Blk$. \subsection{The sides of the signed law}\label{subsec:signed-sides} The joint $2\times2$ block of the preceding subsection needs, on each of its two diagonal sides, a coefficient---the \emph{side}: the multiple of the one-layer companion record placed on that diagonal. For the signed comparison records of $F_1$ and $F_2$ the block is positive already with the two equal sides $\bar H_Xd_\tlaw(X)$, where $d_\tlaw$ is the explicit coefficient computed from the joint Gram matrix in \cref{prop:signed-bounds}(d). The construction instead starts from cheaper auxiliary sides given by a certified formula (\cref{def:side-function}) and increases each by a nonnegative increment to at least $\bar H_Xd_\tlaw(X)$; only the auxiliary price and the increment are then charged. The proposition makes this precise, piece by piece. \begin{proposition}[The sides of the signed law]\label{prop:signed-sides} For a middle piece starting at $X$ let $n_X=\lfloor L_{\rm loc}/\log_-X\rfloor$, assume $n_Xe_0(X)<1$, put $\bar H_X=(1-n_Xe_0(X))^{-1}$, and let $d_\tlaw(X)$ and $c_{\ge2}(X)$ be the constants of \eqref{eq:signed-constants} at $(q_X,r_X)$, with $\tlaw=127/500$ (the functions of \cref{cert:signed-local} evaluate them at the $33$ piece starts). \begin{enumerate}[label=(\roman*)] \item Let $\Blk$ be a middle block of the piece. The signed comparison record of $F_1$ (\cref{def:record:mixture}(c)) satisfies the hypotheses of \cref{lem:record:asymmetric-gram}(b) with $c_{\rm L}=c_{\rm R}=d_\tlaw$ and the support-two constant $c_{\ge2}(X)$, and $c_{\ge2}(X)r_X2^{24}$, and let $T'_p=T[K_{\tlaw,p}]$ be the operator on $L^2(m_0)$ of the signed record at $p$ (the notation $T[\cdot]$ of \cref{prop:signed-bounds}), the combination $P_{++,p}+\frac\tlaw2P_{-+,p}-\frac\tlaw2P_{--,p}$ of its three components (\cref{def:record:mixture}(c)). These are probability couplings with both half marginals $m_0$ (\cref{lem:signed-components}(d)), so $T_{\rm old}$ and $T'_p$ fix the constants on both sides, and the decomposition of $L^2(m_0)$ into the constants and the $m_0$-centred functions reduces the prime Gram. On the constants it is $\bigl(\begin{smallmatrix}1+dr&1\\1&1+dr\end{smallmatrix}\bigr)\succeq0$ for $d\ge0$. On the centred functions, $T_{\rm old}=O_0+R_o$ with $\|R_o\|\le e_oq$, where $O_0=-(A_{\mathbf e}V_{0,m}^*+V_0A_{\mathbf e}^{*_m})$ is the natural leading part, with adjoints in $L^2(m_0)$ (\cref{lem:old-f-law}(f)); and $T'_p=O_0+L^m_{\tlaw,p}+R^{\rm new}_{\tlaw,p}$ with $L^m_{\tlaw,p}=A_{\mathbf a_\tlaw}V_{0,m}^*-V_0A_{\mathbf a_\tlaw}^{*_m}$, the signed leading difference with the unprojected pair feature $A_3$ and the adjoints of $L^2(m_0)$, and $\|R^{\rm new}_{\tlaw,p}\|\le e_{\rm sg}q$ (\cref{prop:signed-bounds}(c)). The leading parts form the operator matrix $G(u_\tlaw,v_\tlaw)$ of the synthesis form of \cref{lem:record:direct-gram}, with $\mathcal H=L^2(m_0)$, $V=V_0$ and the features $A_i$ regarded as maps into $L^2(m_0)$, whose synthesis has squared norm at most the frame $\Gamma_A$ of \cref{lem:actual-features}(d). At $\tside=1$ it gives $G(u_\tlaw,v_\tlaw)\succeq-r\Gamma_As_\tlaw I$. The remainders form the self-adjoint matrix $\bigl(\begin{smallmatrix}R_o&R^{\rm new}_{\tlaw,p}\\R^{{\rm new}*}_{\tlaw,p}&R_o \end{smallmatrix}\bigr)\succeq-(e_o+e_{\rm sg})qI$. As $q=r^2$, the prime Gram with the shifts $dr$ is positive semidefinite for $d\ge s_\tlaw\Gamma_A+(e_o+e_{\rm sg})r=d_\tlaw$, all evaluated at $(1/p,p^{-1/2})$. The function $d_\tlaw$ is nondecreasing in $(q,r)$ (\eqref{eq:signed-constants}), so this is the first hypothesis of \cref{lem:record:asymmetric-gram}(b) with $c_{\rm L}=c_{\rm R}=d_\tlaw$. \emph{Supports of at least two primes.} On every exact support $S\subseteq\Blk$ with $|S|\ge2$ the restrictions of the old and of the signed block operators have norms with sum at most $c_{\ge2}/b$, with $c_{\ge2}$ at $(1/b,b^{-1/2})$, and $c_{\ge2}r<21$}{m>1}}\label{subsec:record:positive_means} The number $\Theta$ in \cref{thm:comparison} is nonincreasing in the mean credit $m$ of (CP7): a larger proved $m$ only helps. We bound the mean energies from the reference side. Each envelope contains $\Nbr$, and $\Nbrz$ is $\mu$ plus positive reserved-diagonal records; at $\iota$ every monomial of the product of $\Nbrz$ and the chosen diagonals is therefore positive semidefinite, and explicit lower bounds for a few monomials may be kept while all others are discarded. The monomials kept are those of the polarized fold diagonals, the chosen side diagonals and the chosen matching diagonals, on sets of at most four distinct blocks, and of five or six blocks of a pool of late pieces. Their energies are bounded below by restoration (\cref{lem:record:restoration}) at the chamber cut where the two-layer fold record is the diagonal copy of its own induced law, and, for the matching diagonals, by the aligned bridge (\cref{lem:record:paired-e-joint}). At the baseline exponent these coupons are necessary for $\Theta<1$ in this construction: they lower $\Theta$ by about $(m-1)/64\approx0.0092$, against a margin $1-\Theta$ of about $2.67\cdot10^{-11}$. \paragraph{Notation.} Energies are those of the toolkit \ref{it:record:E1}--\ref{it:record:E3}: $Y[\kappa]=Y_{\kappa\otimes\mu_{-X}}$ for a measure $\kappa$ on the labels of a set $X$ of atoms, and $Y^{\Nbr}[\kappa]$, $Y^{\Nbrz}[\kappa]$ with $\Nbr_{-X}$, $\mathsf N_{0,-X}$ outside. Let $\Blk$ be a middle block of the piece $[X_i,Y_i)$ (\cref{def:record:exact-blocks}), with least prime $b_\Blk$ and $r_\Blk=b_\Blk^{-1/2}$. For $j\in\{1,2\}$ the normalized one-layer companion $D^j_\Blk$ of $F_j$ is a positive normalized law, fixed samplewise by $\iota$, with uniform one-slot marginals, and so are the selected diagonals $D_{E_s,\Blk}$ of the matching records; $D_{E_s,\Blk}=\operatorname{Diag}_\iota(\Pi^{(1)}_{E_s})$ is the one-layer matching law on the reserved diagonal, whereas $D^j_\Blk$ is the diagonal copy of $\nu_F^{\otimes\Blk}$ placed by $F_j$, and the selected diagonal $D_{F_j,\Blk}=\operatorname{Diag}_\iota(m^{F_j}_{0,\Blk})$ is obtained from it by the density of $m^{F_j}_{0,\Blk}$ relative to $\nu_F^{\otimes\Blk}$. By \cref{def:record:frame} and \cref{lem:record:gram}, \[ (\Nbrz-\mu)_\Blk=\mathsf E_\Blk+H_\Blk,\qquad\mathsf E_\Blk=(E_{\rm add}+G)_\Blk, \qquad E_{{\rm add},\Blk}=\frac{v_{\rm D}r_\Blk^2}{1+h_\Blk}\bigl(D_{E_0,\Blk}+D_{E_1,\Blk}\bigr), \] with $\widetilde\mu_\Blk(1)=1+h_\Blk$, where $h_\Blk$ is the nonroot mass \eqref{eq:record:nonroot-mass}; all summands are nonnegative and reserved diagonal. The fold companion $F_{{\rm fold},\Blk}=v_{\rm D}r_\Blk^2(1+h_\Blk)^{-1}(D^1_\Blk+D^2_\Blk)$ is a summand of $\Nbr$, not of $\Nbrz$; it enters the mean only through the polarization orders $\mathsf E_\Blk\pm F_{{\rm fold},\Blk}\succeq_{\vartheta_0}0$ (\cref{lem:middle-polarization}, \cref{rem:polarization-uses}(3)). By \cref{prop:record:matching}(i), $M_{s,\Blk}-\Nbr_\Blk-K_{s,\Blk}-Q_{E,\Blk}=Q^\circ_\Blk\succeq_\iota0$ (\ref{it:record:E3}). For the piece $i$ we use the piece values $h_i$, $M_i$, $\chi_i$, $\varepsilon_i$ and the density factors $H_i=(1+2/(X_i-4))^{n_i}$, with $n_i=\lfloor L/\log_-X_i\rfloor$ and $L=570$, of \eqref{eq:variance:pieces}, and the caps $C_i$ of \cref{lem:piece-caps}. For a multiset $m$ of pieces, $C_m$, $\eta_m$ and the restored value $\ell_m=\mathcal F(C_m,h_m,M_m,\chi_m)$ are those of the piece data of \cref{subsec:variance:backgrounds}, and a set of distinct middle blocks has the \emph{pattern} $m$ if $m_i$ of its blocks lie in the piece $i$. (Multisets of pieces are written $m$, as in \cref{subsec:variance:backgrounds}, and ``pattern'' here means such a multiset, not a chamber pattern $\phi$; they occur only as indices and in the sums over $|m|$, and are not to be confused with the mean credit $m$ of (CP7).) The factor $H_i$ bounds the density of the actual block marginal $m_{0,\Blk}$ relative to $\nu_F^{\otimes\Blk}$ for every block of the piece: at a prime, $\sup g_0=(p-2)/(p-4)=1+2/(p-4)$, the value of the formula of \cref{lem:old-f-law}(a) at $e_{01}=e_{12}=0$, and a block of the piece has at most $n_i$ primes, all at least $X_i$ (\cref{lem:record:local-domain}). Put \[ c_{E,i}=\frac{v_{{\rm D},i}}{1+h_i},\qquad c_{F,i}=\frac{c_{E,i}}{H_i}, \] the coefficients of the matching diagonals of $E_{\rm add}$ and of the polarized fold diagonals, and let $W_0(m)=W(\varnothing,m;\mathbf1)$ be the distinct-choice weight of \cref{lem:distinct-choice}(a) with unit coefficients: the sum of $\prod_{\Blk\in X}b_\Blk^{-1}$ over the sets $X$ of distinct middle blocks of pattern $m$ is at least $W_0(m)$. Except through the caps $C_i$, these quantities do not depend on $a$. \begin{lemma}[Restored companion energies]\label{lem:record:companion-energy} Let $X$ be a nonempty set of distinct middle blocks, $\Blk\in X$ lying in the piece $i(\Blk)$, and $j\in\{1,2\}$. \begin{enumerate}[label=(\alph*)] \item For every real $\ell$, if $Y[\bigotimes_{\Blk\in X}\Pi_{F_j,\Blk}]\ge(\ell-o(1))Y$, then $Y[\bigotimes_{\Blk\in X}D^j_\Blk]\ge\bigl(\ell/\prod_{\Blk\in X}H_{i(\Blk)}-o(1)\bigr)Y$. In particular, if $X$ has the pattern $m$, then $Y[\bigotimes_{\Blk\in X}D^j_\Blk]\ge(\ell_m/\prod_{i\in m}H_i-o(1))Y$. \item If $X$ has the pattern $m$, then $Y[\bigotimes_{\Blk\in X}D_{E_0,\Blk}]+Y[\bigotimes_{\Blk\in X}D_{E_1,\Blk}] \ge2\bigl([\ell_m-C_m\eta_m]_+-o(1)\bigr)Y$. \end{enumerate} \end{lemma} \begin{proof} (a) Put $\Pi_X=\bigotimes_{\Blk\in X}\Pi_{F_j,\Blk}$. \emph{Contraction at the reserved cut.} By \cref{lem:record:fold-identification}(d), $\Pi_X$ is symmetric at $\iota$ with actual half marginal $m_X=\bigotimes_{\Blk\in X}m^{F_j}_{0,\Blk}$, so the contraction \ref{it:record:P1} gives $Y[\Pi_X]\le Y[\operatorname{Diag}_\iota(m_X)]$. \emph{Density.} For a block $\Blk$ of the piece $i$, the density of $m^{F_j}_{0,\Blk}$ with respect to the half law $\nu_F^{\otimes\Blk}$ (placed by $F_j$) of $D^j_\Blk$ is at most $H_i$ (paragraph above), and densities of products multiply. So the density domination \ref{it:record:P2}, a domination of reserved-diagonal measures, gives $Y[\operatorname{Diag}_\iota(m_X)]\le\prod_{\Blk\in X}H_{i(\Blk)}\, Y[\bigotimes_{\Blk\in X}D^j_\Blk]$. Combining the two steps with the hypothesis proves the first claim. For the second, the blocks of $X$ share the fold chamber $\vartheta_{2j}$ of $F_j$ (\cref{lem:record:fold-identification}(b)), and the piece data give $Y[\Pi_X]\ge(\ell_m-o(1))Y$ (\cref{subsec:variance:backgrounds}, \cref{lem:record:restoration}, with the cap $C_m\ge C_X$ of \cref{lem:piece-caps}). (b) By \cref{subsec:variance:backgrounds}, \cref{lem:record:paired-e-joint}(b) holds for $X$ with $l_0=\ell_m$, $C=C_m$ and $\varepsilon_X\le\eta_m$; and the actual half marginal at $\iota$ of the aligned embedding $E^X_s$ is $\bigotimes_{\Blk\in X}m_{E_s,\Blk}$, so its diagonal copy is $\bigotimes_{\Blk\in X}D_{E_s,\Blk}$. Hence (b) is \cref{lem:record:paired-e-joint}(c), as $[l_0-C\varepsilon_X]_+\ge[\ell_m-C_m\eta_m]_+$. \end{proof} \begin{proposition}[Mean credit]\label{prop:record:mean-credit} Assume, in every middle piece, the protection \eqref{eq:protection}, the side gates $k^{\rm aux}_{s,i}\ge0$ (\cref{prop:signed-sides}) and the matching gates $2q_i\bar I_{2,i}\le A_{E,i}+S_{E,i}$ (\cref{subsec:matching-envelopes}). Then, for $s\in\{{\rm L},{\rm R}\}$, $e_s\ge(m-o(1))Y$ with \begin{equation}\label{eq:mean-credit} m=1+m_F+m_Q-R_{\rm err}e^{T_K+T_{QE}}, \end{equation} where the sums run over the multisets $m$ of pieces, the products over the pieces of $m$ with multiplicity, \begin{align*} m_F&=\sum_{1\le|m|\le4}W_0(m)\,\ell_m\Bigl[2\prod_{i\in m}c_{F,i} +\prod_{i\in m}\frac{k_{{\rm L},i}}{H_i}+\prod_{i\in m}\frac{k_{{\rm R},i}}{H_i}\Bigr] +m^{\rm pool}_F,\\ m_Q&=\sum_{1\le|m|\le4}2W_0(m)\,[\ell_m-C_m\eta_m]_+ \Bigl[\prod_{i\in m}(c_{E,i}+q_i)-\prod_{i\in m}c_{E,i}\Bigr]+m^{\rm pool}_Q, \end{align*} and $m^{\rm pool}_F$, $m^{\rm pool}_Q$ are the late-pool coupons of degrees five and six of \cref{lem:pool-coupons}(b), on the pieces starting at $2^{31}$ or later. Hence (CP7) holds with the mean credit $m$. \end{proposition} \begin{proof} \emph{Step 1: from the envelopes to $\Nbrz$.} In every middle block $0\preceq_\iota\Nbr_\Blk+K_{s,\Blk}+Q_{E,\Blk}\preceq_\iota M_{s,\Blk}$: the bracket measure is positive semidefinite at $\iota$ (\cref{lem:record:gram}(ii)), the chosen diagonals are positive and reserved diagonal (their coefficients are nonnegative by the gates), and the difference is $Q^\circ_\Blk\succeq_\iota0$; outside the middle $M_{s,\Blk}-\mu_\Blk=Q_\Blk\succeq_\iota0$. By the tensor monotonicity of \cref{lem:record:block-gram}(d), applied to the cut matrices at $\iota$ \eqref{eq:cc:kron}, $\bigotimes_\Blk M_{s,\Blk}\succeq_\iota \bigotimes_\Blk(\Nbr_\Blk+K_{s,\Blk}+Q_{E,\Blk})$, and evaluation at $\bar X$ gives $e_s\ge Y_{\widetilde M_s}$ with $\widetilde M_s=\bigotimes_\Blk(\Nbr_\Blk+K_{s,\Blk}+Q_{E,\Blk})$. Let $M_{0,s}$ be the same product with $\Nbrz$ in place of $\Nbr$. Expand both over the set $\mathcal S$ of blocks that carry $K_{s,\Blk}$ or $Q_{E,\Blk}$ and over, at each block of $\mathcal S$, the choice of $K_{s,\Blk}$ or $Q_{E,\Blk}$. Each resulting product $C_{\mathcal S}$ of chosen diagonals (the notation suppresses the choice) is a positive measure whose normalization has uniform one-slot marginals and is admissible (\cref{prop:record:matching}(i)), and its price is the product of the prices $\pi_\Blk$ of its factors; by \ref{it:record:E1}, $|Y^{\Nbr}[C_{\mathcal S}]-Y^{\Nbrz}[C_{\mathcal S}]|\le(1+o(1))R_{\rm err} \prod_{\Blk\in\mathcal S}\pi_\Blk Y$. Summing over all choices gives at most $(1+o(1))R_{\rm err}\prod_\Blk\bigl(1+\pi(K_{s,\Blk})+\pi(Q_{E,\Blk})\bigr)Y\le (1+o(1))R_{\rm err}e^{T_K+T_{QE}}Y$, because the chosen side diagonals cost at most $T_K$ and the chosen matching diagonals at most $T_{QE}$, for either $s$ (proof of \cref{prop:record:matching}(ii)). So $e_s\ge Y_{M_{0,s}}-(R_{\rm err}e^{T_K+T_{QE}}+o(1))Y$. \emph{Step 2: the expansion.} Write $M_{0,s}=\bigotimes_\Blk\bigl(\mu_\Blk+\mathsf E_\Blk+H_\Blk+K_{s,\Blk}+Q_{E,\Blk}\bigr)$ and expand $\mathsf E_\Blk=E_{{\rm add},\Blk}+G_\Blk$ as well. The cut matrix at $\iota$ of every term is a tensor product of positive semidefinite matrices, since $\mu_\Blk\succeq_\iota0$ and the other measures are positive and reserved diagonal; so every term has nonnegative energy (\ref{it:record:E2}), and we may keep some and discard the rest. Keep the term with $\mu$ at every atom, whose energy is $Y$, and, for every set $X$ of distinct middle blocks with $1\le|X|\le4$, or with $|X|\in\{5,6\}$ and all blocks in pieces of the pool, the three families of terms in which the blocks outside $X$ carry $\mu$ and the blocks of $X$ carry \begin{itemize} \item[($\alpha$)] labels in $\{E_{\rm add},G\}$, together $\bigotimes_{\Blk\in X}\mathsf E_\Blk$; \item[($\beta$)] the chosen side diagonal, together $\bigotimes_{\Blk\in X}K_{s,\Blk}$; \item[($\gamma$)] labels in $\{E_{\rm add},Q_E\}$, at least one of them $Q_E$. \end{itemize} These are distinct terms of the expansion: ($\gamma$) has a $Q_E$ label, and ($\alpha$), ($\beta$) have none and differ in every label. All other terms are discarded. The number of middle blocks is finite and does not depend on the scale, so the errors $o(1)Y$ below add up to $o(1)Y$. \emph{Step 3: the empty-$Q$ branch.} ($\alpha$) By the polarization orders $\mathsf E_\Blk\pm F_{{\rm fold},\Blk}\succeq_{\vartheta_0}0$ (\cref{rem:polarization-uses}(3)) and the identity of all degrees \cref{lem:tr:polarization}(d), \[ \bigotimes_{\Blk\in X}\mathsf E_\Blk-\bigotimes_{\Blk\in X}F_{{\rm fold},\Blk} =2^{-|X|}\sum_{\sigma\in\{\pm1\}^X}\Bigl(1-\prod_\Blk\sigma_\Blk\Bigr) \bigotimes_{\Blk\in X}\bigl(\mathsf E_\Blk+\sigma_\Blk F_{{\rm fold},\Blk}\bigr) \succeq_{\vartheta_0}0 . \] The factors $\mu_{\Blk'}$, $\Blk'\notin X$, are reflection positive at $\vartheta_0$, so $Y[\bigotimes\mathsf E_\Blk]\ge Y[\bigotimes F_{{\rm fold},\Blk}]$ (\ref{it:record:E2}). Expand $\bigotimes F_{{\rm fold},\Blk}$ in the measures $\bigotimes_\Blk D^{j_\Blk}_\Blk$; the products with mixed orientations are positive and reserved diagonal, with nonnegative energy, and are discarded; the two common orientations $j\equiv1$, $j\equiv2$ have, by \cref{lem:record:companion-energy}(a), energies at least $\ell_m/\prod_{i\in m}H_i-o(1)$ times $Y$, with the coefficient $\prod_\Blk v_{\rm D}r_\Blk^2/(1+h_\Blk)\ge \prod_\Blk r_\Blk^2\prod_{i\in m}c_{E,i}$. So the terms ($\alpha$) of $X$ have energy at least $(2\prod_\Blk r_\Blk^2\,\ell_m\prod_{i\in m}c_{F,i}-o(1))Y$, the factor $2$ counting the two common orientations. The fold companions are summands of $\Nbr$ and not of $\Nbrz$, so this polarized copy is the only way in which they enter the mean. ($\beta$) Expand $\bigotimes K_{s,\Blk}$ in the same measures and keep the two common orientations: for $s={\rm L}$ they are $\prod_\Blk r_\Blk^2\bigl(\prod_\Blk k_{{\rm L},i(\Blk)}\bigotimes D^1_\Blk +\prod_\Blk k_{{\rm R},i(\Blk)}\bigotimes D^2_\Blk\bigr)$, and for $s={\rm R}$ the same with $D^1$ and $D^2$ exchanged. By \cref{lem:record:companion-energy}(a) both give at least $(\prod_\Blk r_\Blk^2\,\ell_m[\prod_{i\in m}k_{{\rm L},i}/H_i+\prod_{i\in m}k_{{\rm R},i}/H_i] -o(1))Y$: the exact left and right pairing is retained, no ordering of the sides is needed, and both envelopes receive the same credit. The chosen side diagonals carry no factor $1/(1+h_\Blk)$, so the side ratios are $k_{s,i}/H_i$. In the bracket of one fold copy the measure $\Nbrz-\mu$ contains no fold diagonal (\cref{lem:record:gram}), so there are no terms mixing fold diagonals of $\Nbrz$ with the chosen side diagonals. \emph{Step 4: the nonempty-$Q$ branch.} ($\gamma$) Every factor is $c_\Blk r_\Blk^2(D_{E_0,\Blk}+D_{E_1,\Blk})$ with $c_\Blk\in\{v_{\rm D}/(1+h_\Blk),\,q_{i(\Blk)}\}$, so the terms ($\gamma$) of $X$ add up to \[ \prod_\Blk r_\Blk^2\Bigl[\prod_\Blk\Bigl(\frac{v_{\rm D}}{1+h_\Blk}+q_{i(\Blk)}\Bigr) -\prod_\Blk\frac{v_{\rm D}}{1+h_\Blk}\Bigr]\bigotimes_\Blk\bigl(D_{E_0,\Blk}+D_{E_1,\Blk}\bigr). \] The bracket is a polynomial with nonnegative coefficients that is nondecreasing in each $v_{\rm D}/(1+h_\Blk)\ge c_{E,i(\Blk)}$, so it is at least $\prod_{i\in m}(c_{E,i}+q_i)-\prod_{i\in m}c_{E,i}$. Keep the two aligned orientations of $\bigotimes(D_{E_0,\Blk}+D_{E_1,\Blk})$ and discard the others; by \cref{lem:record:companion-energy}(b) their energies add up to at least $2([\ell_m-C_m\eta_m]_+-o(1))Y$. The empty and nonempty $Q$ branches are disjoint, even where their physical diagonals are proportional. \emph{Step 5: summation.} For $1\le|X|\le4$ the bounds of Steps 3 and 4 depend on $X$ only through its pattern $m$ and the factor $\prod_\Blk r_\Blk^2$, and the sum of this factor over the sets of pattern $m$ is at least $W_0(m)$ (\cref{lem:distinct-choice}(a)); all coefficients are nonnegative. This gives the sums over $1\le|m|\le4$. For a set $X$ of $k\in\{5,6\}$ blocks of pieces of the pool, the first assertion of \cref{lem:pool-coupons} gives $Y[\bigotimes_{\Blk\in X}\Pi_{F_j,\Blk}]\ge(\ell_{\mathcal P^k}-o(1))Y$ and \cref{lem:record:paired-e-joint}(b), (c) with the pool data, so Steps 3 and 4 hold with $\ell_{\mathcal P^k}$, $C_{\mathcal P}^k$ and $\eta_{\mathcal P^k}$ in place of $\ell_m$, $C_m$ and $\eta_m$ (\cref{lem:record:companion-energy}(a), and the proof of \cref{lem:record:companion-energy}(b) with these data); the bounds of \cref{lem:pool-coupons}(b) for the sums over these sets of the coefficients of the three branches give the coupons $m^{\rm pool}_F$ and $m^{\rm pool}_Q$, which occupy degrees disjoint from those of the other kept terms. Adding the kept terms and Step 1 gives $e_s\ge(1+m_F+m_Q-R_{\rm err}e^{T_K+T_{QE}}-o(1))Y$ for both $s$. Every restoration is recomputed at the exponent $a$ with the product caps $C_m$ at that exponent, not transported from an estimate at $a_0$, and no lower estimate of an upper-priced norm is used. The closing number $\Theta$ is nonincreasing in $m$ (\cref{rem:cp:monotone}), so certified lower bounds for $m_F$, $m_Q$ and upper bounds for $R_{\rm err}$, $T_K$ and $T_{QE}$ may be used. \end{proof} The chosen side diagonals carry no factor $1/(1+h_\Blk)$, so the side ratios are $k_{s,i}/H_i$. The fold companions of $\Nbr$ carry it, so $c_{F,i}$ keeps $1/(1+h_i)$. The full chosen prices $T_K$ and $T_{QE}$ are charged in the error exponent, as in the matching exponent. The restorations are evaluated at the product caps of the final exponent, with piece data that do not depend on $a$. The following numerical values describe the baseline certificate, before the joint allocation below; they are in \cref{cert:record:means}: $m_F>0.400172842378$, $m_Q>0.190134971388$, of which the terms pooled over the pieces from $2^{31}$ contribute about $1.1951\cdot10^{-7}$ and $6.5884\cdot10^{-7}$ (the degree-six parts of both pooled coupons $m^{\rm pool}_F$ and $m^{\rm pool}_Q$ vanish), $R_{\rm err}e^{T_K+T_{QE}}<3.67071778633\cdot10^{-4}$ and $m>1.589940741988$. % Begin sections/24a_joint_mean \subsection{Allocating the full positive mean jointly with the comparison} \label{subsec:joint-mean} The closing inequality contains the comparison energy with coefficient $63/64$ and the mean energy with coefficient $-1/64$. A positive diagonal occurring in both can therefore reduce the closing bound: subtract its mean coefficient from $63$ times its comparison coefficient, then apply an upper bound to the remaining nonnegative energy. This is the joint allocation of \cref{cor:joint-closing}. We apply it to the positive expansion in Step~2 of \cref{prop:record:mean-credit}. Of the lower bounds retained there (called mean credits), only those supported on one block are used separately here. The following argument replaces the credits on two or more blocks. For a middle block write \[ \alpha_B=\frac{w_{{\rm D},B}r_B^2}{1+h_B},\qquad T_B=E_{{\rm add},B}+H_B =\beta_B(D_{E_0,B}+D_{E_1,B}),\qquad \mathsf E_B=E_{{\rm add},B}+G_B. \] The measures $E_{{\rm add},B},G_B,H_B$, the fold diagonals $D_{F_j,B}$, and the matching diagonals $D_{E_j,B}$ are those defined in \cref{subsec:record:positive_means}; $K_{s,B}$ is the added diagonal on side $s\in\{{\rm L},{\rm R}\}$ of the matching bracket (\cref{prop:record:matching}). Here $\beta_B$ is a local coefficient. The actual chosen diagonals satisfy \begin{equation}\label{eq:joint-resources} \begin{aligned} 2\le\beta_B/\alpha_B&\le R=2.004317,\qquad\sigma=0.3842,\\ Q_{E,B}&\succeq_\iota\alpha_B(D_{E_0,B}+D_{E_1,B}),\\ K_{s,B}&\succeq_\iota\sigma\alpha_B(D_{F_1,B}+D_{F_2,B}). \end{aligned} \end{equation} The density of an actual fold marginal relative to its normalized companion is at most $H_*=1.000003310$. Thus its companion diagonal dominates $H_*^{-1}D_{F_j,B}$. These assertions use the same $33$ physical pieces and chosen sides as \cref{prop:record:matching}. Explicitly, on a piece starting at $X$, \[ \frac{\beta_B}{\alpha_B} \le\frac{v_{\rm D}}{w_{\rm D}} +\frac{6}{\lfloor\sqrt X\rfloor(1-3/X)}\le R, \qquad \frac{\min(k_{{\rm L},i},k_{{\rm R},i})}{w_{{\rm D},i}H_i}\ge\sigma. \] The matching coefficient $q_i\ge w_{{\rm D},i}/(1+h_i)$ and $H_i\le H_*$ complete the checks. Both independent assemblies verify these inequalities piece by piece. \begin{lemma}[Multiaffine allocation constants]\label{lem:joint-multiaffine} Put $l=1/R$, $u=1/2$, and, for $0\le k\le n$, put \[ P_{n,k}=(1+l)^k(1+u)^{n-k},\quad E_{1,n,k}=kl+(n-k)u,\quad E_{2,n,k}=\binom k2l^2+k(n-k)lu+\binom{n-k}2u^2. \] Define \[ \eta_n=\min_{0\le k\le n}\frac{P_{n,k}-1}{E_{2,n,k}} (2\le n\le10), \qquad \zeta_n=\min_{0\le k\le n}\frac{P_{n,k}}{E_{1,n,k}} (1\le n\le9). \] Write $e_1(z)=\sum_i z_i$ and $e_2(z)=\sum_{i0 \qquad(0\le j\le10), \] and the same inequality with $\rho^j$ replaced by $1$ for the tail. These $36$ gates allow the full conservative variance credit on an aligned quartic word, before its weight $1/8$ in the class is taken. Each matching-pair class has a common cap; the pure matching quartics have no new mean subtraction and retain their existing variance gates. For the mixed words the chosen unframed caps are at least $1/4$, and $63/4-\sigma^n\zeta_{j+1}>0$ for $n=1,3,5$, $0\le j\le8$. The exact rational lists and their independent reconstruction are part of \cref{cert:four-routes-closing}. \begin{proposition}[Mean terms with a nonempty upper support]\label{prop:joint-upper-mean} Let $S_u,A_u$ denote just the finite upper comparison assignments, excluding prefix and tail padding. Set \[ C_E=e^{S_u}\cosh A_u-1,\qquad C_O=e^{S_u}\sinh A_u. \] The further joint correction is $\Delta_u-\mathcal R_u$, where \begin{align*} \Delta_u={}&\frac1{64}\left\{ C_E\bigl(\cosh(y)B_\rho+x\sinh(y)F_\zeta\bigr) +C_O\bigl(\sinh(y)B_\rho+x\cosh(y)F_\zeta\bigr)\right\},\\ \mathcal R_u={}&\frac{R_{\rm err}e^{T_K+T_{QE}}}{64} (e^{S_u+A_u}-1). \end{align*} \end{proposition} \begin{proof} On each finite upper block both matching brackets are $\mu_B+Q_B$, with the same positive reserved-diagonal norm envelope $Q_B$. The nonempty-$Q$ part of their tensor product is disjoint from all middle-only terms used above. Fix its skew parity and the exact middle $K_s$ set. If the parities agree, retain the full $T/Q_E/G$ background; otherwise select one additional matching position. The same multiaffine allocation gives the displayed even and odd exponential sums. The new first-stage error is bounded by $\mathcal R_u$, obtained by summing over the entire nonempty upper support, including discarded branches. Every such term has positive upper degree, so it belongs to none of the sixteen exceptional middle classes or their variance credits. After splitting each full middle skew price into its raw arm and positive remainder, the residual gates are $63-\sigma^n\rho^j>0$ and $63-\sigma^n\zeta_{j+1}>0$, with the same finite ranges and uniform tails. Since $\sigma<1$, $n=0$ is the worst case, and the stated rational constants satisfy these gates. Complete this positive residual series as above. The finite upper assignments are used jointly in its positive cost and mean term; they are not lower bounds for the mass of $Q_B$. \end{proof} \space % End sections/24a_joint_mean \paragraph{Hypotheses verified in this section.} \begin{itemize} \item (CP6): for every atom the bracket of \cref{prop:record:matching}(i) holds. $M_{s,\Blk}-\Nbr_\Blk$ is a nonnegative combination of positive reserved-diagonal laws with uniform one-slot marginals, independent of the index: the norm envelopes $D^\epsilon_{\Blk,t}$ of (CP4) of the records other than the fold and matching records, the chosen matching diagonals $Q_{E,\Blk}$ and the chosen side diagonals $K_{s,\Blk}$. Its summed price is at most the $T$ of \cref{prop:record:matching}(ii), with the sides of \cref{prop:signed-sides}. The chosen diagonals are diagonal copies of components of the reference, positive records with admissible normalizations (\cref{def:record:frame} and the paragraph after it); so (CP8)(a) holds for them. \item (CP7): $\frac12(e_{\rm L}+e_{\rm R})\ge(m-o(1))Y$ with $m$ of \eqref{eq:mean-credit}, by \cref{prop:record:mean-credit}. \item Every bound used is an exact relation (orders at $\iota$ and $\vartheta_0$; the expansion and polarization identities; the contraction and density steps), an upper bound from \ref{it:record:E1}, or an exact relation minus such bounds (the restorations, the mean error), and the restorations are positive parts of continuous expressions; so the bound of (CP7) is robust, as (CP8)(b) requires (\cref{lem:record:rec}(i)). The gates of this section, $k^{\rm aux}_{s,i}\ge0$ (positive in every piece), the protection $v_{\rm D}\ge2w_{\rm D}k_{\rm D}$, the matching gates, $n_Xe_0(X)<1$ and $c_{\ge2}(X)r_X0$. These are upper bounds, rounded upward in the record, for the local quantities of \cref{subsec:upper-formulas}, evaluated for blocks of class-three primes at least $X$ and logarithmic length at most $L_{\rm band}$: \begin{itemize} \item $d_\varphi$ bounds the block caps of the two-layer and of the one-layer chamber cut that cut the $\rm L$ coordinate of the graph whose other coordinate has field type $\varphi$ (LL20 and LL10, FL21 and FL11, EL21 and EL11). \item $(f_\varphi,h_\varphi,M_\varphi,t_\varphi)$ are row coefficients of \ref{it:record:upper-F5} valid for the two-layer and for the one-layer rows at $\varphi$; in particular $M_\varphi\ge H+t_\varphi$ and $t_\varphi H<1$ for both. \item The reserved input uses the one-layer quantities alone: LL10, FL11 or EL11 and the one-layer row. \item $k_{\mathfrak t}$ is the block cap $k_{\mathfrak f(\mathfrak t)}$ of the layer cut of the field pair $\mathfrak f(\mathfrak t)$ (LL22, FL22, EL22, FF22, FE22, EE22). The exceptions are $k_{\rm LR}=k_{\rm RL}=k_{\rm G}$ and $k_{\rm LC}=k_{\rm CL}=k_{\rm C}$, the observed merge and constant caps of EL22 (\cref{prop:observed-caps}). \end{itemize} The root entries $d_{\rm L}$ and $k_{\rm LL}$ are the caps of \cref{subsec:record:upper_root}. The values are recorded with the band (\cref{cert:upper-completion}) and summarized in \cref{tab:data:upper-bands}. \item \emph{Weights.} Rational weights $w_{\mathfrak t},v_{\mathfrak t}>0$, indexed by the $25$ states, with $w_{\rm LL}=1$, such that for each chamber coordinate $c\in\{0,1\}$ and each type $\mathfrak t'$ of the other coordinate the five weights $a_{\mathfrak s}=w_{\mathfrak t}$ ($\mathfrak t_c=\mathfrak s$, $\mathfrak t_{1-c}=\mathfrak t'$, $\mathfrak s\in\{\rm L,D,S,R,C\}$) satisfy \begin{equation}\label{eq:upper-slice} a_{\rm D}\ge d\,a_{\rm L},\qquad a_{\rm S}\ge M\,a_{\rm D},\qquad a_{\rm R}\ge f\,a_{\rm D}+h\,a_{\rm S},\qquad a_{\rm C}a_{\rm S}\ge a_{\rm R}^2 \end{equation} with the ordinary input $(d,f,h,M)$ of the field type of $\mathfrak t'$ (forty inequalities); the weights $v$ satisfy the same forty inequalities with the reserved inputs; and \begin{equation}\label{eq:independent-fold-domination} v_{\mathfrak t}\ge k_{\mathfrak t}\,w_{\mathfrak t}\qquad \text{for all $25$ states $\mathfrak t$.} \end{equation} \item \emph{Tail datum.} The \emph{tail datum} is a second set of inputs and weights, evaluated at $2^{64}$ for blocks of primes of either class. It is not the datum of the band $[2^{64},2^{512})$, whose inputs are class-three data. \begin{itemize} \item Its inputs $(d,f,h)$ and caps are integers, valid for blocks of primes at least $2^{64}$ of either class and of length at most $L_{\rm u}$ (\cref{cert:upper-band-inputs}(d)). \item Ordinary inputs: $(d,f,h)=(113,258,120)$ for $\rm L$, $(24,30,11)$ for $\rm F$, $(28,8,1)$ for $\rm E$. \item Reserved inputs: $(12,18,10)$, $(5,5,3)$, $(5,3,1)$. \item $M_\varphi=21/20$ and $t_\varphi=1/50$ for every type and both inputs. \item Caps $k_{\mathfrak t}=k_{\mathfrak f(\mathfrak t)}$ with $k_{\rm LL}=45$, $k_{\rm LF}=9$, $k_{\rm LE}=7$, $k_{\rm FF}=4$, $k_{\rm FE}=3$, $k_{\rm EE}=1$. \item Its $50$ weights satisfy (d). \end{itemize} It is used only by the tail law (\cref{def:tail-law}). \end{enumerate} \end{definition} \begin{remark}[What is a choice]\label{rem:upper-band-choices} The bands, the cells and the integers $n_j$ are choices, and any recorded choice with $n_j\log x_{j+1}\le L_{\rm band}$ is valid. Below $2^{52}$ the integers $n_j$ were chosen with $1/(2a\log x_{j+1})$ as a guide; from $2^{52}$ on the recorded partitions carry the block charges $\mathcal U_d$ of \cref{prop:record:upper}, computed at the anchor exponent $85941/125000000$, which the prices then reprice (\cref{prop:record:upper}(ii)). The bands are short below $2^{52}$ because the root caps, which fix the size of all the weights, fall fast with $X$ ($d_{\rm L}$ is about $12847$ at $\Pthree$, $6569$ at $2^{48}$ and $367$ at $2^{52}$), and each band pays the caps of its own start. Only the $105$ inequalities of (d) matter. The certificate fixes the weights by processing the states in increasing type order and taking for each weight the maximum of its lower bounds, and then checks every inequality exactly. Any positive rational solution, for instance one chosen jointly by optimization, gives the same conclusions. Each band evaluates its inputs at points not above $X$ (\cref{subsec:upper-nonroot}, \cref{cert:upper-band-inputs}). Since positivity is proved block by block and tensorizes factor by factor, different valid input sets may be used on different blocks. The data of a band are valid at every class-three prime $p\ge X$, but a band uses them only on $[X,Y)$. Beyond $2^{512}$ only the tail datum is used. \end{remark} \begin{remark}[Band endpoints]\label{rem:band-endpoints} Band endpoints need not form an equally spaced grid. Each band carries its own complete prime-count, product-budget, restart, endpoint and jump bounds of \cref{lem:record:block-charge}. The bands have disjoint prime supports that cover the range, so the positive band charges add. No boundary term is dropped. \end{remark} \subsection{The two-layer reference}\label{subsec:upper-two-layer} \subsubsection{The two-layer graphs}\label{subsec:push:layer72spectral} \paragraph{How to read the two-letter names.} In the upper range every graph, cut and record carries a short code with one letter for each of the two chamber coordinates. As \emph{field types}, $\rm L$ is the six-object root coordinate, $\rm F$ its three-object fold half, and $\rm E$ the three-object matching coordinate with no forward edges; thus $G_{{\rm FE},2}$ is the two-layer graph with a fold coordinate and a matching coordinate. A cut name adds the number of layers and the cut: the last digit is $0$ or $1$ for the chamber cut in coordinate $0$ or $1$, and $2$ for the layer cut $\iota$; so LL20 is the chamber cut in coordinate $0$ of the two-layer root, and EL22 is the layer cut of the two-layer $\rm EL$ graph. The $25$ \emph{states} $\mathfrak t$ use instead the five pattern types $\rm L,D,S,R,C$ of \cref{def:patterns} in each coordinate, so the state LR has the root pattern in the first coordinate and a merge pattern in the second. Records are usually named by their field types (FF, FE, LE), states by their pattern types (DD, DS); where both occur together the text gives both, as in \cref{prop:forest-records}. For the field types let $O_{\rm L}=\Zsix$ and $O_{\rm F}=O_{\rm E}=\{0,1,2\}$ be the object sets, with the following relations and forward relations. In $\rm L$, $x\to y$ is related if $y\in\{x+1,x-1,\rot x\}$ (the chamber relation $\Rel$ without equality), and forward if $y=\rot x$. In $\rm F$ the relation and the forward relation are their restrictions to $\{0,1,2\}$: the related pairs are $0\to1$, $1\to0$, $1\to2$, $2\to1$ and $0\to2$, and only $0\to2$ is forward. In $\rm E$ all ordered pairs of distinct objects are related and none is forward. For field types $\varphi_0,\varphi_1$ and $j\in\{1,2\}$ let $G_{\varphi_0\varphi_1,j}$ be the oriented graph on $O_{\varphi_0}\times O_{\varphi_1}\times\Lambda_j$, $\Lambda_2=\{0,1\}$, $\Lambda_1=\{0\}$, with an edge $(u_0,u_1,\ell)\to(v_0,v_1,\ell')$ whenever both coordinate relations $u_0\to v_0$, $u_1\to v_1$ hold and at least one of them is forward; there is no condition on the layers. The \emph{root} is $G_{\rm LL,2}$. \begin{lemma}[Two-layer geometry]\label{lem:upper-geometry} \leavevmode \begin{enumerate}[label=(\alph*)] \item Every $G_{\varphi_0\varphi_1,j}$ is an oriented graph. The root has $72$ vertices and $720$ edges, every vertex has $10$ out-neighbours and $10$ in-neighbours, and it contains every query $(u_0,u_1,\ell)\to(\rot u_0,\rot u_1,1-\ell)$; in particular the twelve queries \eqref{eq:upper-twelve} and $\mathcal E_6$ are edges of the root. \item The chamber reflections of a coordinate of type $\rm L$ and the layer swap are automorphisms of the graphs; every permutation of $O_{\rm E}$ is an automorphism of a graph with a coordinate of type $\rm E$ (exchangeability). \item The subgraph of $G_{{\rm L}\varphi,j}$ induced on the plus half $\{0,1,2\}$ of its first coordinate is $G_{{\rm F}\varphi,j}$, and likewise in the second coordinate. The subgraph of $G_{\varphi\varphi',2}$ induced on the layer $\ell=0$ is $G_{\varphi\varphi',1}$. \item For every $\varphi$ and $j$ the graphs $G_{{\rm F}\varphi,j}$ and $G_{{\rm E}\varphi,j}$ induce the same graph on the objects $\{0,1\}$ and on the objects $\{1,2\}$ of their first coordinate, and neither has an edge inside one object. \end{enumerate} \end{lemma} \begin{proof} (a) If $u\to v$ is forward in $\rm L$, then $v\to u$ is not related: $u\notin\{\rot u\pm1,\rot^2u\}$, as $\rot u-u=\pm2$; in $\rm F$ the pair $2\to0$ is not related. An edge needs a forward coordinate, whose reverse is not related, so no pair carries edges in both directions; and no loop occurs, since related objects are distinct. At a vertex of the root there are $3\cdot3$ pairs of related successors, of which $2\cdot2$ have no forward coordinate; so there are $5$ out-neighbours in each layer, $10$ in all, and by the same count $10$ in-neighbours; so $72\cdot10=720$ edges. Both coordinates of a query are forward. (b) A chamber reflection $\vartheta_a$ commutes with $\rot$ (\cref{lem:slot-array}(i)) and maps $x\pm1$ to $\vartheta_a(x)\mp1$; the relations do not involve the layer; and $\rm E$ has all distinct pairs and no forward pair. (c) Inside $\{0,1,2\}$ the only forward pair of $\rm L$ is $0\to2$, since $\rot1=5$ and $\rot2=4$; and edges carry no layer condition. (d) Between the objects $0,1$ and between $1,2$ the relations of $\rm F$ and $\rm E$ are the same (both directions, none forward); inside one object the relation fails. The script \path{research/push_2026_10_17/sparse/layer72.py} reconstructs these facts for all eighteen graphs. \end{proof} The spectral caps concern twelve cuts, and the merge and constant marginals of one of them (\cref{subsec:upper-observed}). The name of a cut lists the field types of its graph, its number of layers and the cut: $0$ and $1$ for the chamber cut $\vartheta_{c,0}$ of the coordinate $c$, and $2$ for the layer cut $\iota$. The two \emph{root cuts} are LL20 and LL22. The ten \emph{nonroot cuts} are the chamber cuts LL10, FL21, EL21, FL11, EL11 of the $\rm L$ coordinate and the layer cuts FL22, EL22, FF22, FE22, EE22; coordinate interchange and the chamber automorphisms give all other cuts. By \cref{lem:upper-geometry}(c) the half graph of a chamber cut of $G_{{\rm L}\varphi,j}$ is $G_{{\rm F}\varphi,j}$, which is the graph of the aligned fold, and the half graph of a layer cut is the one-layer graph. Each cut, with a deletion order fixed once, is spectral data in the sense of \cref{def:spec:data}; we write $\Op$ for its normalized cut operator on $L^2(\mu)$, where $\mu=\lambda_p(G^+)$ is the half law, the graph law of the half graph $G^+$ (\cref{lem:spec:cutkernel}); the actual half marginal is $\varrho\,\mu$, with $\varrho=\Op\one$. The root cuts have $n=36$ half vertices, maximal degree $\Delta=20$, internal degrees $d^0_k\le10$ and cross degrees $r_k\le12$ (LL20) and $r_k\le10$ (LL22). \subsubsection{The \texorpdfstring{$25$}{25} summand types}\label{subsec:layer72:upper} For a block $\Blk$ of odd primes and field types $\varphi_0,\varphi_1$ let $\lambda_{\varphi_0\varphi_1}=\lambda_\Blk(G_{\varphi_0\varphi_1,2})$ and $\lambda^{(1)}_{\varphi_0\varphi_1}=\lambda_\Blk(G_{\varphi_0\varphi_1,1})$ be the two-layer and the one-layer field laws (\cref{def:graphs:labeling}): at every prime of $\Blk$ independently, the uniform law on injective strict-square labellings. (In this section \emph{pattern summand} below is what is meant by a summand of $\pi_{\mathfrak t}$ or of $\mu_\Blk$; \emph{component} keeps its glossary meaning as a summand of $\nu_\Blk$.) These are the field laws of \cref{def:two-coordinate-five-type}, with the layer set $\Lambda=\{0,1\}$, respectively $\{0\}$. For a state $\mathfrak t$ and patterns $\phi=(\phi_0,\phi_1)\in P_{\mathfrak t_0}\times P_{\mathfrak t_1}$, the \emph{pattern summand} $\Pi_{\mathfrak t,\phi}$ (respectively $\Pi^{(1)}_{\mathfrak t,\phi}$) is the image of the two-layer (one-layer) field law of the field types of $\mathfrak t$ under the emission $e_\phi$; objects outside the image of $\phi$ are forgotten (the \emph{hidden} objects of merges and constants). The two-layer and one-layer components are written into the slots $(u_0,u_1,\ell)$ and, for one-layer components, copied onto both layers by $\operatorname{Diag}_\iota$. Put \[ \pi_{\mathfrak t,2}=\sum_\phi\Pi_{\mathfrak t,\phi},\qquad \pi_{\mathfrak t,1}=\sum_\phi\Pi^{(1)}_{\mathfrak t,\phi}, \] of mass $m_{\mathfrak t}$. The \emph{rows} of the coordinate $c$ at the field type $\varphi$ are the objects of the coordinate $c$ of a field law whose other coordinate has type $\varphi$; their law is a five-type datum (\cref{def:five-type-datum}) whose conditional reference is the law of one outer row given the middle row under the $\rm E$ law (\cref{subsec:upper-rows}). At $\iota$ the half graph of a two-layer graph is its one-layer graph (\cref{lem:upper-geometry}(c)); this is why one-layer copies on the reserved diagonal can cancel the negative envelopes at $\iota$ (\cref{rem:fold-pairing}). \subsubsection{The reference law \texorpdfstring{$\mu_\Blk$}{mu\_B} and its weights}\label{subsec:independent-fold-weights} \begin{definition}[The upper reference]\label{def:upper-reference} Let $\Blk$ be a block of an upper band with least prime $b$ and $r=b^{-1/2}$, and let $w_{\mathfrak t},v_{\mathfrak t}$ be the weights of the band (\cref{def:record:upper-bands}(d)). The \emph{reference} of $\Blk$ is $\mu_\Blk=\widetilde\mu_\Blk/P_\mu(r)$, where \[ \widetilde\mu_\Blk=\sum_{\mathfrak t}w_{\mathfrak t}r^{\deg\mathfrak t}\,\pi_{\mathfrak t,2} +r\sum_{\mathfrak t}v_{\mathfrak t}r^{\deg\mathfrak t}\operatorname{Diag}_\iota(\pi_{\mathfrak t,1}), \] \begin{equation}\label{eq:independent-fold-polynomial} P_\mu(r)=\sum_{\mathfrak t}m_{\mathfrak t}\bigl(w_{\mathfrak t}r^{\deg\mathfrak t} +v_{\mathfrak t}r^{\deg\mathfrak t+1}\bigr)\ge1 . \end{equation} \end{definition} The polynomial $P_\mu$ has constant coefficient $w_{\rm LL}=1$, the weight of the root $\pi_{\rm LL,2}$; its coefficient of degree $d$ is the total weight of the records of overall degree $d$. The one-layer weights $v_{\mathfrak t}$ form an array of their own: they satisfy the one-layer completion inequalities with the one-layer inputs and, separately, the domination \eqref{eq:independent-fold-domination} by the cap of their own state. Weights $v_{\mathfrak t}$ proportional to $w_{\mathfrak t}$, with one factor for all states, would have to dominate the largest cap $k_{\rm LL}$ ($9381.137478$ at $\Pthree$, $2070.828678$ at $2^{49}$) in every state, while the other caps are below $7.01$. \subsection{The two principal cuts}\label{subsec:record:upper_root} Two of the twelve cuts are the full degree-twenty root: the first-coordinate cut LL20, which gives the ordinary input $d_{\rm L}$, and the layer cut LL22, which gives the reserved cap $k_{\rm LL}$. Their half graphs have $36$ vertices, each of degree twenty in the root, and their caps are the largest of all: at $\Pthree$ they are about $12847$ and $9381$ ($2557$ and $2071$ at $2^{49}$), against at most $25$ for the other cuts. Two routes bound them. \paragraph{The setting.} Let $(G,\vartheta,U^+,\mathfrak o)$ be the spectral data of LL20 or LL22, with $n=|U^+|=36$, cross signs $\varsigma$, cross degrees $r_k$, internal degrees $d^0_k$ and $\Delta=20$. The threshold hypothesis (S1) of \cref{def:spec:data} is $e_{20}(p,72)<1$ and $p>4n^2=5184$, with the coarse count error $e_t(p,n)$ of \eqref{eq:graphs:et}. Let $\mu=\lambda_p(G^+)$ be the half law and $\Op$ the normalized cut operator on $L^2(\mu)$, with the character expansion \eqref{eq:record:root-kernel} of the root kernel (\cref{lem:spec:expansion}), its nonstar part $T_{\rm ns}$, its collision part $T_{\rm coll}$ and the star function $h_\star$ of \eqref{eq:star-function}. At $p\equiv3\pmod4$ this is the setting of route~B (\cref{subsec:spec:routeB}): $\Hmat^+=\Hmat$, and the two signs of the Schur test \eqref{eq:record:schur} give complex-conjugate matrices. The hard root also permits the sign filter of \cref{lem:signed-collisions}. On its two cuts the exact pin counts are \begin{equation}\label{eq:upper-signed-collision-counts} \begin{array}{c|r|r|r|r} &\text{all pins}&\text{compatible}&\sum a_{ij}&\sum\widetilde a_{ij}\\ \hline \mathrm{LL20}&1296&168&54583296&2752512\\ \mathrm{LL22}&1296&324&55738368&39813120 \end{array} \end{equation} These integers are obtained directly from the $72$-vertex root and its two reflections (\cref{cert:astra-local}). They sharpen the collision input while preserving the accepting graph. The certified band caps below retain their larger collision assignments, so the filter requires no alteration of the selected comparison laws or closing table. \paragraph{Route~B at the two root cuts.} \Cref{thm:record:direct-star} uses no completed conditional law of the root and no completion-variance denominator, only (S1). Its Route-B frame numbers (not those of the middle frame) \ref{it:record:star-H1} are those of \cref{lem:record:frame-inputs}; its inputs \ref{it:record:star-H3} are the following. \begin{lemma}[Root inputs]\label{lem:record:direct-star-inputs} Let the cut be LL20 or LL22, so that $n=36$, $d^0_k\le10$ and $r_k\le12$, and let $p\equiv3\pmod4$ satisfy (S1). Then hypothesis \ref{it:record:star-H3} of \cref{thm:record:direct-star} holds with the following choices. \begin{enumerate}[label=(\roman*)] \item $M_\star$ is the quantity of \cref{prop:advance:ordered-star} for a fixed total order of $U^+$, with the relative count errors $e_i=e^-_{d^0_i}(n)$ of \eqref{eq:graphs:graded}. \item $z_\star=r^2(\sum_iK_i+|B_{\rm even}|)$, with the $K_i$ of \cref{prop:advance:ordered-star} and $B_{\rm even}$ of \cref{lem:star-mean} for the signs $\chi(\varsigma_{jk})$ of the class $p\equiv3\pmod4$, and $Z_\star=2z_\star$. \item $N_{\rm ns}=\sum_{k=2}^4C_k(Q)r^k$, where $Q\le p$ is a real number at which (S1) holds and $C_k(Q)$ bounds the nonstar coefficients of \cref{cor:extraction-leaf}(b) for a refinement of the compressed partition (\cref{lem:advance:compressed-partition}) with witnesses of sizes $2$, $3$ and $4$. \begin{itemize} \item These coefficients are evaluated with the graded error pairs and the special values $\mathsf S_{\rm m}(s)$, $\mathsf S_\varrho(s)$ of \cref{def:extraction:records} and \eqref{eq:leaf-factors}, and summed exactly over the complete nonstar histogram of the cut, under the monotone-signature gate \eqref{eq:monotone-signature}. \item At an interpolation point $Q$ (a prime size, not an exponent anchor) they are this sum. \item Between consecutive interpolation points $P_0\le Q4n^2$ is a real number (in the applications a power of two) with $e_\Delta(p_0,2n)<1$. Suppose that $\mathbf R\succeq0$ and that the numbers of \cref{lem:record:direct-star-inputs}, with $Q=p_0$ in (iii), give $\eps_Z<1$ and $g_{\rm root}r_0<1$ at $r_0$. Let $p\ge p_0$ be a prime with $p\equiv3\pmod4$. Then the numbers of \cref{lem:record:frame-inputs,lem:record:direct-star-inputs} at $p$ satisfy \ref{it:record:star-H1}--\ref{it:record:star-H3} with the same $s_\star,g_\star$, and \[ g_{\rm root}(p)\le g_{\rm root}(p_0),\qquad B_{\rm top}(p)\le B_{\rm top}(p_0):=\frac{p_0\,\eps_\varrho(p_0)^2}{1-g_{\rm root}(p_0)p_0^{-1/2}} . \] Consequently, for every block $\Blk$ of primes $p\ge X\ge p_0$ with $p\equiv3\pmod4$ and $\log q_\Blk\le L_{\rm u}$, the normalized block root operator is at least $-d\,b_\Blk^{-1/2}$, with $d=g_{\rm root}(p_0)\exp\bigl(B_{\rm top}(p_0) L_{\rm u}/(X\log X)\bigr)$. More generally, let $s_\star,g_\star$ satisfy \eqref{eq:record:schur} at $p_0$ as above, with $\mathbf R\succeq0$, and let $X\ge p_0$ be real with (S1) at $X$. Suppose the numbers of \cref{lem:record:direct-star-inputs} at $r_X=X^{-1/2}$, with $Q=X$ in (iii), give $\eps_Z<1$ and $g_{\rm root}(X)r_X<1$. Let $\Blk$ be a block of primes $p\ge X$ with $p\equiv3\pmod4$ and $\log q_\Blk\le L'\le L_{\rm u}$. Then the normalized block root operator of $\Blk$ is at least $-d\,b_\Blk^{-1/2}$ with $d=g_{\rm root}(X)\exp\bigl(B_{\rm top}(X)L'/(X\log X)\bigr)$, where $B_{\rm top}(X)=X\eps_\varrho(X)^2/(1-g_{\rm root}(X)r_X)$. \end{lemma} \begin{proof} Write every quantity as a function of $r\in(0,r_0]$. By \cref{lem:spectral-monotone}(a) the frame quantities $\eps_V$, $\eps_\times$, $\eps'_H$, $\theta^\mu_j$, $\hat E^2$ and $\eps_{\ne}$ are admissible (\cref{lem:majorant}); for $\eps'_H$ this includes the entries $\beta_{kl}$ of \eqref{eq:spec:beta}, maxima of two branches that equal their first branches (the proof of \cref{lem:spectral-monotone}). Hence $\eps_{\rm rem}$, $\eps_{\mathbf B}$, $\eps_{\mathbf W}$, $\eps_{\mathbf{EW}}$, $\alpha_\star$ and $\beta_\star$ are at most their values at $p_0$. The matrices $\Delta^E$, $\Hmat$ and $\mathbf R$ depend on $p$ only through its class. So $\mathbf R+\beta_\star I\succ0$ at $p$, because $\mathbf R\succeq0$ and $\beta_\star\ge\eps_{\mathbf B}\ge\norm\Hmat_{\rm row}/(p-1)>0$; and \eqref{eq:record:schur} holds at $p$ by \cref{lem:majorant}(d), since $g_\star/\alpha_\star$ does not decrease and $\beta_\star$ does not increase. For the inputs: $M_\star/r$ and $z_\star/r^2$ are admissible (\cref{rem:pivot-order}), hence so are $(M_\star^2+z_\star^2)/r=r(M_\star/r)^2 +r^3(z_\star/r^2)^2$ and $Z_\star$; $N_{\rm ns}/r=\sum_kC_k(p_0)r^{k-1}$ is a polynomial in $r$ with nonnegative coefficients; and $D_{\rm col}/r$, for the fixed orders, is at most its value at $p_0$ (\cref{lem:oct24-collision}(e)). Thus $\eps_Z$, $\eps_{\rm soft}/r$, $g_{\rm root}$ and $\eps_\varrho/r$ are at most their values at $p_0$: $\eps_Z<1$, so \ref{it:record:star-H3} holds at $p$; $g_{\rm root}(p)p^{-1/2}\le g_{\rm root}(p_0)r_0<1$; and $B_{\rm top}(p)=(\eps_\varrho/r)^2/(1-g_{\rm root}r)\le B_{\rm top}(p_0)$. For the block, the operator is $\bigotimes_{p\in\Blk}\Op$ with $-g_{\rm root}(p_0)p^{-1/2}I\preceq\Op\preceq(1+B_{\rm top}(p_0)/p)I$ at every $p\in\Blk$ (\cref{thm:record:direct-star}(c),(e)), and \cref{lem:spec:tensorcomp} gives the bound, since $\sum_{p\in\Blk}1/p\le L_{\rm u}/(X\log X)$ (\cref{lem:majorant}(c)). For the general form, the first part of the proof, at $r=r_X\le r_0$, gives \ref{it:record:star-H1} and \ref{it:record:star-H2} at $X$ with the same $s_\star,g_\star$, and \ref{it:record:star-H3} at $X$ is the hypothesis $\eps_Z<1$. The rest of the proof then runs with $X$ in place of $p_0$ for the inputs: for $p\ge X$ the numbers of \cref{lem:record:direct-star-inputs}, with the coefficients $C_k(X)$ held fixed, are at most their values at $X$, so $g_{\rm root}(p)\le g_{\rm root}(X)$ and $B_{\rm top}(p)\le B_{\rm top}(X)$, and $\sum_{p\in\Blk}1/p\le L'/(X\log X)$. This is the endpoint form of the construction: the exact Schur witness of an anchor stays valid at every larger point because every frame, star-Gram and cross error there is at most its anchor value; this holds by admissibility, and the certificate also checks it separately for each error (\cref{cert:upper-root-caps}). \end{proof} \begin{certificate}[Route~B star-synthesis bounds and Schur tests at the root cuts]\label{cert:record:direct-star} For LL20 and LL22 and $p_0=2^b$, $b\in\{47,48,49,50,51,52\}$: \begin{enumerate}[label=(\alph*)] \item (S1) holds, with $e_{20}(p_0,72)\le0.3978$ at $2^{49}$ and $e_{20}(2^{47},72)$ about $0.796$; all count errors of \cref{lem:record:frame-inputs,lem:record:direct-star-inputs} are below one; $\mathbf R\succeq0$ by exact elimination. \item The frame numbers of \cref{lem:record:frame-inputs}, evaluated in outward rational arithmetic and rounded upward, and stored rationals $s_\star,g_\star$ satisfy \eqref{eq:record:schur}. The records contain $32$ such tests for $b\ge49$ (two cuts, four endpoints, both prime classes, both signs; the class-one tests are those of the variant described after \cref{lem:record:frame-inputs}, and class three runs through its real $72\times72$ embedding) and $16$ for $b\in\{47,48\}$ (two cuts, two endpoints, both classes, both signs), each certified positive semidefinite by exact rational elimination at the value of $g_\star$ found for its sign; the left side of \eqref{eq:record:schur} is nondecreasing in $g_\star$, so both signs hold at the larger value, which is the $g_\star$ used. The class-three matrices are those of the construction; since their two signs are complex conjugate, one sign per cut and endpoint would suffice. At class three, $g_\star=3193/32$ (LL20) and $18199639/500000$ (LL22) at $2^{47}$, and $98128393/10^6$ and $35898609/10^6$ at $2^{48}$. \end{enumerate} The records are \path{research/roadmap_2026_10_18/item12/direct_star_spectral.json} ($2^{49}$ to $2^{52}$), with the model and geometry exports \path{direct_star_models_export.json} and \path{direct_star_geometry_export.json} of the same directory, produced by \path{direct_star_spectral.py}, and \path{direct_star_lower_endpoints.json} of the same directory ($2^{47}$, $2^{48}$; four tests per row, status \texttt{PASS\_EXACT\_DIRECT\_STAR\_ROOT}). The exact eliminations at $2^{49},\dots,2^{52}$ and the frame errors were repeated by an independent rational implementation, the four class-three tests at $2^{47}$ by \path{research/advance_2026_10_24/upper/lower_p47/native_review.json}, and the class-three tests at $2^{48},\dots,2^{51}$ again by \path{research/continuation_2026_10_24/upper_arithmetic/fractional_roots_review.json}. The class-three anchor rows ($g_\star$, frame errors, $M_\star$, $z_\star$, collision bound) for $2^{47},\dots,2^{52}$ are \path{direct_star_collision_v2.json} (same directory); the reviews \path{research/advance_2026_10_24/upper/review_lower_native47.py} and \path{research/continuation_2026_10_24/upper_arithmetic/review_roots.py} read them. The records also derive root caps from these tests with the star constants of both prime classes; the derived class-one caps are not used, since the bands below $2^{52}$ have no class-one primes. Floating-point computations only proposed the rationals $s_\star,g_\star$; the proof uses the exact tests. \end{certificate} \begin{certificate}[Root caps below $2^{52}$]\label{cert:upper-root-caps} \sloppy For LL20 and LL22 and every band $[X,Y)$ below $2^{52}$, the inputs of \cref{lem:record:direct-star-inputs} are taken at the band's start $X$. The nonstar coefficients come from the complete histograms with the graded errors and special values, at the $19$ anchors $2^{47},\dots,2^{52}$, $167\cdot2^{40}$ and $j2^{42}$ for $j\in\{40,42,43,44,46,48,50,52,56,60,80,96\}$, and are interpolated log-convexly between them (\cref{lem:logconvex-coefficients}). The scalar stars $M_\star$, $z_\star$, $Z_\star$, the ordered coincidence bound $D_{\rm col}$ and the rank-one and soft terms are evaluated at $X$; the frame witness $(s_\star,g_\star)$ is that of the band's anchor (\cref{cert:record:direct-star}): $2^{47}$ below $2^{48}$, and $2^b$ on $[2^b,2^{b+1})$ for $b=48,\dots,51$, every frame, star-Gram and cross error at $X$ being checked to be at most its anchor value. These give $\eps_Z<1$, and $g$ below is an upper bound for $g_{\rm root}$, rounded upward to $10^{-8}$, with $gX^{-1/2}<10^{-3}$. By \cref{lem:record:monotone-endpoint} with $L'=L_{\rm band}$, the block caps are $d=g\exp(B_{\rm top}L_{\rm band}/(X\log X))$, rounded upward to $10^{-6}$; they are the root entries $d_{\rm L}$ (LL20) and $k_{\rm LL}$ (LL22) of the band. Selected rows (the record holds all $301$): \begin{center} \footnotesize\setlength{\tabcolsep}{3.5pt} \begin{tabular}{@{}llllllll@{}} \toprule & & \multicolumn{3}{c}{LL20} & \multicolumn{3}{c@{}}{LL22}\\ \cmidrule(lr){3-5}\cmidrule(l){6-8} $X$ & $L_{\rm band}$ & $g$ & $B_{\rm top}<$ & $d_{\rm L}$ & $g$ & $B_{\rm top}<$ & $k_{\rm LL}$\\ \midrule $\Pthree$ & $559$ & $12846.88753069$ & $2.52265\cdot10^{8}$ & $12847.187931$ & $9381.04100550$ & $1.10946\cdot10^{8}$ & $9381.137478$\\ $2^{48}$ & $566$ & $6568.89967376$ & $8.59331\cdot10^{7}$ & $6568.933791$ & $5072.00168224$ & $3.71450\cdot10^{7}$ & $5072.013069$\\ $2^{49}$ & $578$ & $2556.55783215$ & $2.30412\cdot10^{7}$ & $2556.559613$ & $2070.82814422$ & $8.51920\cdot10^{6}$ & $2070.828678$\\ $2^{50}$ & $555$ & $1165.55594825$ & $9.20408\cdot10^{6}$ & $1165.556101$ & $942.50581374$ & $2.71889\cdot10^{6}$ & $942.505851$\\ $2^{51}$ & $566$ & $612.94721642$ & $4.71877\cdot10^{6}$ & $612.947237$ & $472.87513870$ & $1.13250\cdot10^{6}$ & $472.875143$\\ $\frac{127}{64}2^{51}$ & $577$ & $370.09363192$ & $2.81352\cdot10^{6}$ & $370.093636$ & $262.47992391$ & $5.79331\cdot10^{5}$ & $262.479925$\\ \bottomrule \end{tabular} \end{center} At $2^{52}$ and above the Route~A caps $367,\dots,113$ and $261,\dots,45$ of \cref{cert:upper-completed-root} are used. The records are: \begin{itemize} \item the coefficient tables \path{research/further_2026_10_25/upper/special_coefficients/LL20_coefficients.json} and \path{LL22_coefficients.json} ($19$ anchors); \item their review \path{research/further_2026_10_25/upper/special_coefficients_review.json} (\texttt{PASS\_INDEPENDENT\_EVEN\_COUNT\_ROOT\_COEFFICIENTS}, refinement \texttt{PASS\_INDEPENDENT\_FORCED\_COINCIDENCE\_ROOT\_COEFFICIENTS}): the $30645955$ histogram rows summed exactly, $1596$ upward vertex factors, $114$ directed coefficients, the $80$ monotone-signature gates \eqref{eq:monotone-signature} (every step $s\to s+1$ up to $s+1=\Delta=20$) and $3024$ per-signature maxima; \item the root assembly \path{research/advance_2026_10_24/upper/apply_even_roots.py} (the formulas of \cref{thm:record:direct-star} with the interpolation), applied by \path{research/further_2026_10_25/upper/apply_special_roots.py} and written into the field \texttt{even\_root\_evidence} of \path{research/further_2026_10_25/upper/upper_dense_refined.json}; \item its review \path{research/further_2026_10_25/upper/special_upper_review.json} (\texttt{PASS\_INDEPENDENT\_EVEN\_COUNT\_ROOT\_UPPER}: $602$ fresh root and block caps, $1806$ log-convex coefficients); \item the scalar root data at the band starts ($M_\star$, $z_\star$, $Z_\star$, $D_{\rm col}$, the rank-one and soft terms, the frame errors): for the $45$ bands below $2^{48}$ the field \texttt{roots} of the band record, computed with the anchor witness at $2^{47}$ by \path{research/advance_2026_10_24/upper/lower_prefix.py} and replayed by \path{review_lower_native47.py} of the same directory in the regenerated upper chain of \path{regenerate_upper_chain.py}, whose $51$ independent reviews the record \path{research/advance_2026_10_24/verification/selected.json} lists; for the bands of $[2^{48},2^{52})$ \path{research/continuation_2026_10_24/upper_arithmetic/fractional_roots.json}, reviewed by \path{fractional_roots_review.json} of that directory (\texttt{PASS\_INDEPENDENT\_FRACTIONAL\_ROOT\_ASSEMBLY}: $16$ exact anchor tests, $1536$ frame dominations). The nonstar values stored with these scalar data come from earlier coefficient tables and are not used: the caps take $N_{\rm ns}$ from the coefficient tables of the first item. \end{itemize} \end{certificate} \paragraph{Where the root cost lies.} At $\Pthree$ the nonstar term $N_{\rm ns}/r\approx12715$ is about $99\%$ of $g(\mathrm{LL20})$, while the frame coefficient is $g_\star=3193/32$, about $99.8$, and the coincidence term $D_{\rm col}/r$ about $18.6$: the root is expensive because of its many two-matchings, not because of its frame. \paragraph{Route A from $2^{52}$: the completed root.} From $2^{52}$ on, the root caps come from the Route~A criterion \cref{thm:spectral-criterion}, whose coupling inputs integrate the internal neighbourhoods of the root through its completed conditional law (\cref{subsec:spec:completion-variance}). The criterion accepts any admissible values of its perpendicular and coupling inputs; the root caps use the following ones (\cref{rem:spectral-criterion:uses}(iii)). \begin{lemma}[Completed-root caps]\label{lem:upper-completed-root} Let the cut be LL20 or LL22, let $p_0$ be a real number with (S1) at $p_0$, and let $\mathfrak c\in\{1,3\}$. At every prime $p\ge p_0$ with $p\equiv\mathfrak c\pmod4$ the following are inputs of \cref{thm:spectral-criterion}, with the admissibility that it requires. \begin{enumerate}[label=(\roman*)] \item \emph{Perpendicular inputs.} $N_{\rm ns}=\sum_{k=2}^4C_k(Q)r^k$ with the nonstar coefficients of \cref{cor:extraction-leaf}(b) at a fixed $Q\le p_0$ at which (S1) holds; $D_{\rm col}=\min(D_{\rm ord},D_{\rm nat})$, a minimum as in \cref{lem:oct24-collision}(e); $M_\star$ the larger over the two classes of the bound of \cref{prop:advance:ordered-star}; and $\eps_Z$ the smaller of $2(P_{\rm st}+W_{\rm st})+N_{\rm ns}+D_{\rm nat}$ and $Z_\star+N_{\rm ns}+D_{\rm col}$, with the standard star constants $P_{\rm st},W_{\rm st}$ of \cref{lem:spec:stars} and $Z_\star$ twice the larger over the two classes of $z_\star$ (\cref{lem:star-mean}). \item \emph{Coupling inputs.} $R_+$ of \cref{prop:spec2:mucentre}\ref{it:centre:sup}, formed with this $\eps_Z$; $\eps_H=\min(\eps'_H+\eps_X,\eps^{\rm loc}_H)$ (\cref{lem:push:conditionalgram}); $\Gamma_E=\min(\hat E^2,\Gamma^{\rm loc}_E)$ (\cref{lem:projection-diagonal}), the relative completion variances being bounded by \cref{lem:push:localvariance}, whose two-variable bounds use the coefficient triples of \cref{thm:dl:H2} (\cref{rem:dl:H2-sharp}(ii)); and, for $\mathfrak c=1$, $\bar\zeta$ the minimum of \cref{lem:spec2:parity-transfer}, with $\eps_\varrho=R_Z(M_\star+N_{\rm ns}+D_{\rm col})$. \end{enumerate} Consequently, if at $r_0=p_0^{-1/2}$ these inputs give $\eps_Z<1$, $\bar\eps_V<1$ and $\ell^{\rm loc}_k>0$ for every $k\in U^+$, and the tests \eqref{eq:spectral-test} of the class $\mathfrak c$ hold for both signs, then the conclusions of \cref{thm:spectral-criterion} hold at every prime $p\ge p_0$ with $p\equiv\mathfrak c\pmod4$; and if $g\ge g_{\mathfrak c}$ and $gr_0<1$, then for every block $\Blk$ of such primes, all at least $X\ge p_0$, with $\log q_\Blk\le L_{\rm u}$, the normalized block root operator is at least $-d\,b_\Blk^{-1/2}$, with $d=g\exp(B_{\rm top}L_{\rm u}/(X\log X))$ and $B_{\rm top}=p_0\eps_\varrho(r_0)^2/(1-gr_0)$. \end{lemma} \begin{proof} (i) $N_{\rm ns}$ bounds $\norm{T_{\rm ns}}$ by \cref{cor:extraction-leaf}(b), and $D_{\rm col}$, $D_{\rm nat}$ bound $\norm{T_{\rm coll}}$ by \cref{lem:oct24-collision}(e). By \cref{lem:star-mean} with \cref{prop:advance:ordered-star}, for the signs of the class of $p$ (the half law is a pinned half law, as in the proof of \cref{lem:record:direct-star-inputs}), $\norm{h_\star-\E_\mu h_\star}\le M_\star$ and $2|\E_\mu h_\star|\le Z_\star$; the maxima over the classes cover both. With the standard star inputs (\cref{prop:spec2:mucentre}\ref{it:centre:standard}) both forms of $\eps_Z$, and so their minimum, are admissible in \cref{prop:spec2:mucentre}\ref{it:centre:inputs}. (ii) These are admissible inputs of the coupling block \cref{cor:spec2:coupling}, by the lemmas cited. Finally $N_{\rm ns}/r=\sum_kC_k(Q)r^{k-1}$ is a polynomial with nonnegative coefficients, $D_{\rm col}/r$ and $D_{\rm nat}/r$ are admissible by \cref{lem:oct24-collision}(e), $M_\star/r$ and $z_\star/r^2$ by \cref{rem:pivot-order}, and $P_{\rm st}/r^2$, $W_{\rm st}/r$ are constants (\cref{lem:spectral-monotone}(c)); so both forms of $\eps_Z$, and their minimum, are admissible (\cref{lem:majorant}(ii)). $\Gamma_E$, $\eps_H$ and $\bar\zeta$ are admissible by \cref{lem:spectral-monotone}(a),(c),(d): the count errors $\epsilon^\pm_t$ of \cref{subsec:spec:completion-variance} are polynomials in $r$ with nonnegative coefficients and at most the coarse errors $e_t$, so the denominators of \cref{lem:push:localvariance}(b) are positive by (S1), and $\ell^{\rm loc}_k>0$ at $r_0$. So \cref{thm:spectral-criterion} applies, and \cref{cor:spectral-criterion-blocks}, with $P=X$, gives the block bound. \end{proof} \begin{certificate}[Completed-root caps]\label{cert:upper-completed-root} For LL20 and LL22 at every band start $p_0=X$ from $2^{52}$ on, with the inputs of \cref{lem:upper-completed-root}, the evaluator asserts $\eps_Z<\frac12$, $\bar\eps_V<1$, $\ell^{\rm loc}_k>0$ for every $k$ and $gr_0<1$; the matrix tests \eqref{eq:spectral-test} hold for both prime classes and both signs (four exact rational tests per cut and threshold); and the recorded numbers give the block caps $d=g\exp(B_{\rm top}L_{\rm u}/(X\log X))