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math.PR — Probability

Quantitative analysis of critical-window profiles for autocatalytic emergence

Contributed by Michael Mislan

The critical-window law for reflexively autocatalytic and food-generated (RAF) sets in the reversible binary-polymer model states that, when the mean number of reactions catalysed per molecule grows like λn\lambda n, the RAF probability converges to Sν(1−e−λ)S_\nu(1-\mathrm{e}^{-\lambda}), where SνS_\nu is the probability that ordinary reversible closure of the food set is unbounded in an infinite field of independently open reaction channels. The law is known for the ordered split-position catalogue (ν=sp\nu=\mathrm{sp}) and for the commuting-factor quotient catalogue (ν=qt\nu=\mathrm{qt}). It is an existence theorem: it names the limit but says nothing effective about its value, its shape near zero, or what a finite network actually does. This paper answers those three questions. For both profiles, a construction gives a terminating algorithm which, given rational openness aa and rational tolerance ε\varepsilon, returns a rational interval of width below ε\varepsilon containing Sν(a)S_\nu(a), with an explicit approximation error 1/m+(2L+1−2)(1−aL+1)r1/m+(2^{L+1}-2)(1-a^{L+1})^r for a computable seed length LL and record index rr, uniform on every openness interval bounded away from zero. The key estimate is a finite-cap record contraction proved without conditioning on survival and without independence between repair attempts. Second, tracking total word length along productive closure histories replaces a coefficient of order (Jr)\binom{J}{r} over enormous channel caps by Crν≤36r2r(r−1)/2C_r^\nu\le36^r2^{r(r-1)/2}, giving log⁡Sν(a)≤−log⁡2(1/a)/(2log⁡2)+O(log⁡(1/a))\log S_\nu(a)\le-\log^2(1/a)/(2\log2)+O(\log(1/a)) and exact certificates such as Sν(10−20)<10−629S_\nu(10^{-20})<10^{-629}. Third, at fixed word length nn the probability that some singleton RAF exists is exactly 1−(1−p)2481-(1-p)^{248} (split) or 1−(1−p)2341-(1-p)^{234} (quotient), so the finite RAF probability is linear in pp at zero while the limiting profile is flatter than every power; this order-of-limits effect is quantified with rational two-sided predictions and two fully explicit examples at n=16n=16. Further results give strict monotonicity of the profile, an effective global modulus of continuity, terminating inverse-probability brackets, and non-analyticity at zero. The effective evaluator, its error contract with the finite catalytic model and productive-history extraction are checked in Lean~4; the printed numerical bounds are checked by the accompanying replay script; the sharper counting theorem, the singleton law and the regularity results have conventional proofs and are labelled as such.

Primarily AI-generated textHuman understanding: some partsautocatalytic setscomputable analysiscritical windowfinite-size effectslow-intensity asymptotics

math.QA — Quantum Algebra

Low-rank Grothendieck rings: an AI-assisted classification project, constructions, and open problems

Contributed by Sebastien Palcoux

We present a public research project on the Grothendieck rings of complex fusion categories of rank at most eight. The project reports unrestricted classification theorems in ranks two, three, and four, and classifications within specified fusion-multiplicity bounds in ranks five through eight, with two rank-six categorification questions unresolved. Its resources include research manuscripts, an exact fusion-ring census, verification code, and an interactive atlas. We describe seven constructions that are promising candidates for new tensor categories, subject to a separate assessment of their novelty up to tensor equivalence. We also state the two open problems explicitly. This announcement records the project's claims and their verification status; it invites independent mathematical review and does not provide a new proof of the complete classification.

Primarily AI-generated textHuman understanding: some partsAI-assisted mathematicsFusion categoriesGrothendieck ringscategorificationfusion multiplicitylow ranknear-group categories

math.DS — Dynamical Systems

Attracting oscillations in sequential distributive multisite phosphorylation

Contributed by Michael Mislan

The sequential distributive nn-site phosphorylation cycle with one kinase and one phosphatase admits attracting positive periodic orbits under mass-action kinetics for every n≥3n\ge3. An explicit three-site family has a fixed positive equilibrium, a transversal imaginary-eigenvalue crossing, a stable complementary spectrum and a negative first Lyapunov coefficient. A site-addition argument extends the supercritical Hopf bifurcation to every larger site count. Together with the one-site calculation and Vassena's two-site exclusion, this makes three the exact threshold for Hopf bifurcation in this family. Dynamic sequestration of the shared enzymes supplies the feedback: the equilibrium, productive fluxes and statically eliminated vector field remain fixed while stability changes. Further results compare enzyme clamps and selective reduction, quantify flux and amplitude laws, validate two finite-amplitude attracting orbits, and give a driven thermodynamic realization. Exact algebra and interval certificates support the quantitative claims; numerical continuation is distinguished from proof. A registered Lean theorem independently establishes an existential affine family with attracting periodic orbits for every n≥3n\ge3. The manuscript's arbitrary-parent site-addition theorem and its quantitative extensions go beyond that registered statement.

Primarily AI-generated textHuman understanding: some partsHopf bifurcationattracting periodic orbitsenzyme sequestrationmultisite phosphorylation

math.CT — Category Theory

The Grothendieck construction between the telescope monad and contextads

Contributed by Kotaro Kamiya

A telescope is a list of stages in which each stage is a family indexed over the Grothendieck construction of the previous ones. The telescope monad stacks stages as the free-monoid 2-monad on spans, whereas a contextad collapses two stages into one by a dependent sum. This paper derives both from the span of single stages, and thereby explains why the strict algebras of the telescope monad are contextads. The link is the Grothendieck extension of a span. Because it is monoidal and preserves coproducts, it turns the telescopes into the free monad on the extension of the span of stages and the stage contextad into the Grothendieck monad, whose Kleisli arrows are the contextful arrows. The main theorem identifies the stage contextad with the pseudo-algebra of the telescope monad transported from the display contextad. Its structure map is the dependent sum, which the extension turns into the iterated multiplication of the Grothendieck monad.

A mix of human-written and AI-generated textHuman understanding: some partsGrothendieck constructioncomprehension categorycontextaddependent sumtelescope

math.CO — Combinatorics

Bounds for Erdős Problem #188: 7≤k≤607\le k\le 60

Contributed by Carson Crocker

Let ℓk\ell_k denote kk collinear points with consecutive distances 11. Erdős Problem #188 asks for the least kk such that the plane can be colored red and blue with no two red points at distance 11 and no blue copy of ℓk\ell_k. Previous work gives 6≤k≤63306\le k\le 6330, with the lower bound due to Tsaturian and the upper bound due to Currier, Mody, Xie and Zhang. We prove 7≤k≤607\le k\le 60. For the lower bound we show that every red/blue coloring of the plane contains two red points at distance 11 or a blue ℓ6\ell_6, following the skeleton of Arman and Tsaturian's proof in three dimensions; four distance lemmas are reduced to explicit unsatisfiable propositional formulas, certified by DRAT proofs. For the upper bound we give an explicit periodic coloring whose red set consists of 9090 closed regular 2424-gons of 4848 different sizes, all of diameter less than 0.9990.999, in each period, with rational centers and sizes. Any two cells are either far apart (all distances between their points exceed 11) or close together (all distances are less than 11), which is checked in exact arithmetic for all periodic translates and rules out red unit pairs. That every ℓ60\ell_{60} contains a red point is proved by a computer-assisted verification: for every unit direction uu, the sets R−juR-ju, j=0,…,59j=0,\dots,59, cover the period torus, with every inclusion checked in rigorous ball arithmetic. A second, separately written program, based on a reduction to one-dimensional covering problems solved in outward-rounded interval arithmetic, confirms this. The computations, the verification code and drafts of the text were produced with AI tools under the author's direction; all proof certificates and verification programs are public (doi:10.5281/zenodo.23405962).

Primarily AI-generated textHuman understanding: some partsDRATErdős problemsEuclidean Ramsey theorySATinterval arithmeticperiodic coloringunit distance

math.CO — Combinatorics

Three conjectures on the first two graph eigenvalues

Contributed by Idris Ali Shaik

Let λ₁(G) ≥ λ₂(G) be the two largest adjacency eigenvalues of a finite simple graph G on at least two vertices. We resolve the three conjectures appearing as 1.15–1.17 in Kannan, Kumar and Pragada. First, for every noncomplete graph, we prove λ₁(G)² + λ₂(G)² ≤ 2 Σ_{e∈E(G)} (1 − 1/c(e)), where c(e) is the largest order of a clique containing e. Second, we construct connected (K₅ minus one edge)-free graphs of arbitrarily large size that violate the exact color-critical bound proposed by Li, Liu and Zhang. Third, for every fixed F with χ(F) = r + 1 ≥ 3, we prove, uniformly over F-free graphs with m = e(G) → ∞, λ₁(G)² + λ₂(G)² ≤ 2(1 − 1/r)m − ((r − 2)/r)Δ(G) + o_F(m), where Δ(G) is the maximum degree. The coefficient of the degree term is best possible. The arguments use the half-plane complete-positivity theorem of Coutinho, Liu, Spier, Tang and Zhang, together with an explicit connected construction, weighted clique removal and spectral separation of vertices of high degree. Theorems 1.1–1.3 are formalized in Lean 4 and registered as PALOMAR-2026-10-15-000015 v1, PALOMAR-2026-10-16-000012 v1 and PALOMAR-2026-10-17-000005 v1, respectively.

A mix of human-written and AI-generated textHuman understanding: all partsadjacency eigenvaluesextremal graph theoryspectral graph theory

math.CO — Combinatorics

A Product Formula for Partition-Restricted Boundary Hypermatrix Counts

Contributed by YURAN XIU

We prove the Koprowski--Lewis product conjecture for nondegenerate 2×(k+1)×k2\times(k+1)\times k hypermatrices over finite fields with two partition-shaped layers of prescribed zeros. The result holds for every positive kk, every finite field, and every admissible pair of partitions. After fixing the first slice, nondegeneracy is equivalent to simplicity of a partial linear map. Applying the simple-extension theorem of Arora, Ram, and Venkateswarlu inside the successive allowed row spaces gives the product directly. We include an elementary proof of that extension theorem and justify the equivalence with the defining projective critical locus of the hyperdeterminant. The complete counting statement and its semantic equivalences have been checked in Lean. HAL deposit: hal-05800194v1.

Primarily AI-generated textHuman understanding: no partsLean formalizationenumerationfinite fieldshypermatrixproduct formula

math.CO — Combinatorics

Tools for proving that graphs are not graceful

Contributed by Boon Suan Ho

A graph with mm edges is graceful if its vertices can be labeled with distinct integers in [0,m][0,m] whose edge differences are exactly 1,…,m1,\dots,m. Graceful labelings have been constructed for sixty years, but there are few general methods for showing that a graph is not graceful. We start from a single generating-function identity that restates gracefulness, and derive three tools from it: residues at roots of unity, extending the classical parity condition; positivity on the unit circle, whose semidefinite form amounts exactly to the Goemans–Williamson max-cut relaxation tested against the minimum of the Dirichlet kernel; and the label interval itself, which forces the labels of a dense subgraph to have a large span. The consequences include new families of ungraceful graphs: every edge-transitive graph that contains K6K_6, the Paley graphs P(q)P(q) with q≥37q\ge37, the Kneser graphs K(n,k)K(n,k) with n≥5.61kn\ge5.61k, almost every dd-regular graph with d≥84d\ge84, and the polarity graphs ERq\mathrm{ER}_q with q≥23q\ge23, which contain no 44-cycle. For the semidefinite form of positivity we also determine exactly what it can prove, and we show that a planar refinement is strictly stronger: it excludes the Kneser graph K(11,2)K(11,2) with any seven edges deleted.

Primarily AI-generated textHuman understanding: some partsDirichlet kernelGolomb rulerdifference setsgraceful labelingmax-cutsemidefinite programming

math.CO — Combinatorics

No lattice tiling of Z35\mathbb{Z}^{35} or Z805\mathbb{Z}^{805} by Lee balls of radius three

Contributed by Deep Bhattacharjee, Ushashi Bhattacharya

We prove that there is no lattice tiling of Z35\mathbb{Z}^{35} or of Z805\mathbb{Z}^{805} by Lee balls of radius three. These were the only cases left open by Xiao and Zhou among the Lee balls of dimension at least three and radius at least two with fewer than 2302^{30} points, so the lattice Golomb--Welch conjecture holds for all of them.

A mix of human-written and AI-generated textHuman understanding: some partsGolomb-Welch conjectureLee metricgroup ringlattice tilingperfect code

math.CO — Combinatorics

A graph with three card types and five vertex orbits

Contributed by Deep Bhattacharjee, Ushashi Bhattacharya

We prove that the answer to part~(b) of Problem~20.71 of the Kourovka Notebook is yes: there is a connected graph on 6363 vertices with exactly three isomorphism types of vertex-deleted subgraphs whose automorphism group has five orbits on the vertices. The graph is a Cayley graph of a Suzuki 22-group of order 6464 with one vertex removed.

A mix of human-written and AI-generated textHuman understanding: some partsCayley graphSuzuki 2-groupdivisible design graphpseudosimilar verticesvertex-deleted subgraph

math.CO — Combinatorics

Every odd antihole is strongly chromatic-choosable

Contributed by Deep Bhattacharjee, Ushashi Bhattacharya

We prove the complete Fiujlaali--McDonald conjecture on odd antiholes unconditionally: for every ℓ≥3\ell\ge3 the only assignments of (ℓ−1)(\ell-1)-element lists from which the odd antihole $\cbar{2\ell-1}$ cannot be coloured are the constant ones. Consequently, an odd-hole-free kk-critical graph of maximum degree Δ\Delta containing an odd antihole of length 2(Δ−k)+72(\Delta-k)+7 is that antihole.

A mix of human-written and AI-generated textHuman understanding: some partschromatic-choosabilitycolouringcritical graphodd antiholeodd hole

math.CO — Combinatorics

The sl(2)\mathfrak{sl}(2) weight system at c=−3/32c=-3/32 extends to a graph 4-invariant

Contributed by Deep Bhattacharjee, Ushashi Bhattacharya

We prove unconditionally the conjecture of Fomichev, Karev, Pavutnitskiy and Usanov that the specialization of the sl(2)\mathfrak{sl}(2) weight system at c=−3/32c=-3/32 extends to a 44-invariant of graphs. The extension is ξ(G)=(−32)−nSG(−2)\xi(G)=(-32)^{-n}S_G(-2), where SG(N)S_G(N) counts with signs the assignments of 22-element subsets of {1,…,N}\{1,\dots,N\} to the nn vertices of GG.

A mix of human-written and AI-generated textHuman understanding: some partsClifford algebrafour-term relationintersection graphoscillator representationweight system

math.AP — Analysis of PDEs

Non-unique vanishing-viscosity solutions of 2D Euler with vorticity in LpL^p

Contributed by Umberto Pappalettera, Massimo Sorella

For every finite p>2p>2, we construct one real compactly supported zero-circulation initial vorticity in L1(R2)∩Lp(R2)L^1(\mathbb R^2)\cap L^p(\mathbb R^2) whose unforced Navier--Stokes evolutions have two distinct strong vanishing-viscosity accumulation paths. Both limits are renormalized unforced Euler solutions with the same strong initial trace. The construction uses a fixed infinite concentric stack, a smooth unstable fourfold profile, actual positive scalar envelopes, and a finite nonlinear expansion retaining the interacting harmonic histories. Discounted source history is controlled through the complete prospective receiver stop, and exact-cap normalization yields a depth-uniform outgoing reset. Protected first crossings, phase degree and a sparse phase assignment then separate the two limits. The analytical preliminaries, finite-sector spectral scope, source-reference comparison and uniform parameter order are included in the proof.

Primarily AI-generated textHuman understanding: no parts

math.AG — Algebraic Geometry

The fifteenth cohomology of moduli spaces of stable curves

Contributed by zeming sun, guoxiong gao, shurui liu

We determine the fifteenth cohomology of the moduli stack of stable curves M‾g,n\overline{\mathcal{M}}_{g,n} in every genus gg and number of markings nn, with its symmetric-group action, by providing explicit multiplicity formulas for its simple constituents. We also prove the generalized Hodge conjecture in this case. The main result of this paper was obtained using the Pharos system. The author has reviewed the arguments and developed an understanding of the proof. On the basis of this review, the author believes the paper to be correct.

Primarily AI-generated textHuman understanding: some partsHodge structurescohomologygeneralized Hodge conjecturemoduli spaces of stable curvesmotives

math.AG — Algebraic Geometry

A Counterexample to Beauville's Stability Conjecture

Contributed by Yi Gu, Lifan Guan

We construct a morphism f:X→Yf: X\to Y from a genus-two curve to an elliptic curve such that f∗Lf_*\mathcal L is unstable for every $\mathcal L\in\Pic^3(X)$. This gives a counterexample to a conjecture of Beauville.

A mix of human-written and AI-generated textHuman understanding: all partsDirect imagesFrey–Kani construction.stability

math.AG — Algebraic Geometry

Dense Algebraic Loci of Hodge Classes

Contributed by Deep Bhattacharjee, Ushashi Bhattacharya

We prove unconditionally that the Hodge conjecture is equivalent to two statements about abelian varieties, that the locus on which either statement holds is dense in every family and is either the whole family or a meagre set, and that the real multiplications by 5\sqrt5, 6\sqrt6, 7\sqrt7 and by the cubic fields $\QQ(\zeta_{7})^{+}$ and $\QQ(\zeta_{9})^{+}$ are algebraic on explicit families of K3 surfaces, the cubic ones on the surfaces of Mumford type whose quaternion algebra is ramified at two real places. For each of the two statements we build the object it needs next, a complex on a product of two Weil fourfolds and a class on an abelian fourteenfold, prove what it does, and prove at which step it stops. Both statements remain open.

A mix of human-written and AI-generated textHuman understanding: some partsHodge conjectureK3 surfacesWeil classesabelian varieties

cs.CC — Computational Complexity

The Exact Junta Bound for Degree-Two Boolean Functions on q-ary Hamming Cubes

Contributed by YURAN XIU

We determine the maximum number of relevant variables of a Boolean function of degree at most two on a finite alphabet. For every integer q≥2q\geq2, this maximum is exactly max⁡{4,q+1}\max\{4,q+1\}. Here degree means Hamming, or junta, degree: the function is a sum of real-valued functions, each depending on at most two coordinates. We also prove that any such function with more than four relevant variables has a selector coordinate: after that coordinate is fixed, the function depends on at most one other coordinate. The proof combines saturation on a binary four-dimensional restriction with a rigidity argument that applies to every symbol of the original alphabet. Two disjoint interactions force a four-junta; a function with more than four relevant variables has a star of interactions. The exact bound and selector theorem have been formalized in Lean 4, with transitive dependencies using only the standard axioms of Lean and mathlib.

Primarily AI-generated textHuman understanding: no partsBoolean functionsHamming graphsLean formalizationdegree twojunta theoremrelevant variables

cs.CC — Computational Complexity

Set Cover by Cyclic Rotations Is NP-Complete

Contributed by YURAN XIU

Given an explicitly listed binary pattern of positive length nn and a nonnegative integer bb in binary, can at most bb cyclic rotations of the pattern cover all nn positions? We prove that this decision problem is NP-complete. The reduction constructs a pattern in a cyclic group of polynomial order and outputs its entire indicator word. Its principal ingredient is a replicated-marker construction: a cover within the budget must choose one translate in every layer, and each failed difference constraint leaves a block of more holes than the remaining translates can cover. Combining this construction with the known embedding of graph cliques into circulant graphs using distinct three-term sums gives a polynomial-time reduction from 33SAT. The theorem allows every subset, including the empty pattern, and every binary budget. A Lean formalization checks the mathematical reduction, the full-word polynomial-time programs, NP membership, and the unconditional NP-hardness foundation. HAL deposit: hal-05800233v1.

Primarily AI-generated textHuman understanding: no partsLean formalizationNP-completenesscyclic rotationsset cover

cs.CC — Computational Complexity

A Polynomial Separation for Adaptive Fourier-Overlap Parity Decision Trees

Contributed by YURAN XIU

Consider the parity decision tree rule that, at every nonconstant restriction, queries a nonzero character maximizing the intersection of the current Fourier support with its translate. We construct an explicit infinite family for which every adaptive policy obeying this rule has polynomial worst-case depth, although an unrestricted parity decision tree has logarithmic depth. For every ℓ≥1\ell\geq1, let R=2ℓR=2^\ell. Our function has n=4ℓ−1+R2ℓ+Rn=4\ell-1+R^2\ell+R input bits and exactly k=R6−R5+Rk=R^6-R^5+R nonzero Fourier coefficients. Every history-dependent maximizing policy terminates and computes the function, but has a feasible path of length at least R>k1/6R>k^{1/6}; an explicit unrestricted tree has depth at most 5ℓ≤log⁡2k5\ell\leq\log_2 k. The construction places one pointer behind each cell of a finite-field affine partition, with all pointers accessing a shared data table. After any sequence of equal-answer table comparisons, exact signed Fourier coefficients force every maximizing query to compare two remaining table blocks. This invariant accommodates all tie choices and all resulting table partitions. The complete separation, including the specified polynomial-field representation and the existence of every operational policy's finite run, has been checked in Lean. The result concerns this particular support-overlap rule; it is not a lower bound against arbitrary parity decision trees. HAL deposit: hal-05800236v1.

Primarily AI-generated textHuman understanding: no partsFourier analysisLean formalizationadaptive algorithmsparity decision trees

math.NT — Number Theory

On Landau--Siegel zeros

Contributed by Ben Green

This is a variant of the short OpenAI proof that there do not exist Landau-Siegel zeros. In v2, two parameters are decoupled to give a better constant in the main theorem.

Primarily human-written textHuman understanding: all parts

math.NT — Number Theory

Polylogarithmic Descent for Almost All Collatz Orbits in Natural Density

Contributed by Idris Ali Shaik

Korec proved that, for each fixed θ > log 3/log 4, almost every positive integer n has a Collatz iterate below n^θ in natural density. Tao proved descent below every prescribed diverging threshold in logarithmic density. We obtain polylogarithmic descent in ordinary natural density within logarithmically many steps, with bounds on the preceding orbit values. The shortcut map T sends even n to n/2 and odd n to (3n+1)/2. The unaccelerated map Col sends even n to n/2 and odd n to 3n+1. For any prescribed positive function f(n) → ∞, however slowly, we prove that almost every positive integer n, in natural density, has nonnegative integers k = k(n) and ℓ = ℓ(n) satisfying T^k(n) = Col^ℓ(n) < (log n)^A_FP f(n), where A_FP ≈ 9.9911 is an explicit exponent. The shortcut time is k = c_* log n + O_f(√(log n log log n)), where c_* = 2/log(4/3). The leading time c_* log n is predicted by the average logarithmic contraction of the equally weighted multipliers 1/2 and 3/2. The unaccelerated time is ℓ = (3/2)c_* log n + O_f(√(log n log log n)). Both orbits are bounded by nf(n) up to their respective times. For each fixed A > A_FP, put q = A/(2A_FP) − 1/2. For sufficiently large X, all but at most C_A X/(log X)^q integers n ≤ X satisfy the same conclusions with target (log n)^A and bound n(log n)^q on both orbits. The constant C_A and the time-error constants depend only on A. The proof counts finite parity sequences exactly and follows first passages through decreasing thresholds. We count later failures among the original starting values, without assuming that values reached after a descent are uniformly distributed. For starting values 2^M ≤ n < 2^(M+1), only O(√(M log M)) cumulative passage times need to be counted at each threshold. A finite random-walk survival estimate supplies the additional saving needed at the critical exponent. Density-one descent below a fixed multiple of (log n)^A_FP is not established, and the pointwise Collatz conjecture remains open. The theorem for arbitrary f is formalized in Lean 4 with Mathlib and registered as PALOMAR-2026-08-26-000005, version 4.

A mix of human-written and AI-generated textHuman understanding: all partsCollatz mapalmost all Collatz orbitsfirst passagenatural densityparity vectorspolylogarithmic descentstopping time

math.NT — Number Theory

Rational points on elliptic curves that are primitive modulo a positive proportion of primes

Contributed by Manjul Bhargava

In 1977, Lang and Trotter conjectured that, subject to certain necessary arithmetic restrictions, a rational point PP of infinite order on an elliptic curve EE over $\Q$ should generate its reduction modulo infinitely many primes pp---and indeed should do so for a specified positive density of primes. However, to date, even this infinitude was not known unconditionally for any explicit pair (E,P)(E,P). For the curve E:y2=x3−2xE:y^2=x^3-2x and point P=(2,2)P=(2,2), we prove the existence of infinitely many---and indeed a positive lower density of---primes for which the reduction of PP generates $E(\F_p)$. More precisely, we prove that a common zero-free half-plane ℜs>1−1/N\Re s>1-1/N for Dedekind zeta functions gives a lower density of at least c/(Nlog⁡N)c/(N\log N), with c>0c>0 independent of NN. The announced theorem of Cureton and Thorner provides N=32N=32. Our proof combines this input with the marked Type~II estimates of OpenAI, a sieve with varying cofactor, and estimates for division fields and heights. The same method also applies to other CM elliptic curves and points.

A mix of human-written and AI-generated textHuman understanding: some parts

math.AG — Algebraic Geometry

A Probabilistic Proof of a Positivstellensatz of Baldi-Sinn-Telek-Weigert

Contributed by Colin Tan

The AI gives a probabilistic proof of a uniform-denominator Positivstellensatz of Baldi--Sinn--Telek--Weigert for Laurent polynomials whose induced homogeneous form is strictly positive on the nonnegative part of a projective toric variety. Only this abstract was human-written. Three classical tools from mathematical statistics and probability theory were used by the AI: the Barndorff-Nielsen completion of discrete exponential families, sufficiency-based invariance under exponential tilting following Halmos--Savage and Van Campenhout--Cover, and the conditional limit theorem (equivalence of ensembles) of Diaconis--Freedman.

Primarily AI-generated textHuman understanding: no partsPositivstellensatzexponential familieslimit theoremtoric variety

math.PR — Probability

A nontrivial critical window for autocatalytic emergence in the binary polymer model

Contributed by Michael Mislan

The limiting probability is determined for a reflexively autocatalytic and food-generated (RAF) set in two reversible binary-polymer models. The models have the same molecules and food but distinguish reaction identities differently: the split-position catalogue retains ordered factorizations, whereas the quotient catalogue merges swapped factors exactly when they commute. With independent molecule--reaction catalysis, one mark shared by both directions, and mean catalysis fnf_n per molecule satisfying fn/n→λ>0f_n/n\to\lambda>0, the RAF probability converges in either model to Θν(λ)=Sν(1−e−λ),ν∈{sp,qt},\Theta_\nu(\lambda)=S_\nu(1-e^{-\lambda}),\qquad \nu\in\{\mathrm{sp},\mathrm{qt}\}, where SνS_\nu is the survival probability of infinite ordinary reversible food closure in the corresponding independent open-reaction field. Each profile is continuous and nondecreasing, lies strictly between zero and one at every finite positive intensity, and tends to zero and one at its two endpoints. Thus the entire linear scale is a nontrivial critical window, replacing the finite-step conjecture of Hordijk and Steel in the stated model. The common mechanism is uniform growth from a fixed supplied seed, followed by same-parameter richness and an exact law for complete catalytic pruning histories. A shared proof is given, including the explicit quotient transfer: deterministic closure and RAF equivalence project independent split marks to heterogeneous OR marks, rather than to the homogeneous quotient ensemble. The profiles satisfy Θsp(λ/2)≤Θqt(λ)≤Θsp(λ)\Theta_\mathrm{sp}(\lambda/2)\le\Theta_\mathrm{qt}(\lambda)\le\Theta_\mathrm{sp}(\lambda); productive food gateways give the conventional bounds Θsp(λ)≤1−e−32λ\Theta_\mathrm{sp}(\lambda)\le1-e^{-32\lambda} and Θqt(λ)≤1−e−30λ\Theta_\mathrm{qt}(\lambda)\le1-e^{-30\lambda}. The quotient gateway-conditioned bulk-factor limit is also identified. It concerns structural autocatalysis, without assertions about reaction kinetics or thermodynamic viability.

Primarily AI-generated textHuman understanding: some partsautocatalytic setsbinary polymer modelcritical windowreaction channelsreversible closure

math.CO — Combinatorics

A Formally Verified Certificate Proof of the Maximum Number of Stable Matchings for Six Men and Six Women

Contributed by YURAN XIU

We give a complete Lean 4 verification of the theorem that the maximum number of stable matchings for six men and six women with strict complete preferences is f(6)=48. Jo (2026) previously proved the unrestricted upper bound, and Benjamin, Converse, and Krieger (1995) supplied an attaining construction. Our contribution is an alternative, fully formalized proof using a finite certificate; the value 48 and the unrestricted theorem are already known. We reduce stable matchings of arbitrary profiles to order ideals of sequences of cyclic partner exchanges in which no man revisits a partner. A weighted frontier recurrence counts these ideals, and a sum of permanents bounds every future continuation. These bounds yield a finite certificate with 135,828 states. The complete argument, including the reduction for arbitrary profiles, certificate soundness, all concrete checks, and an attaining profile, has been formalized and checked in Lean 4. The final unconditional theorem depends only on the standard axioms of Lean and mathlib.

Primarily AI-generated textHuman understanding: no partsLeanextremal combinatoricsformal verificationstable marriagestable matchings

math.CO — Combinatorics

Pattern-avoiding binary arrays and a Stirling-type table: explicit formulas, exact recurrence orders, and non-D-finiteness

Contributed by Yunkun Song

Let ak(n)a_k(n) be the number of n×kn\times k binary arrays in which no row contains 001001 or 010010 and no column contains 001001 or 011011 as three consecutive entries (OEIS A207123). Splitting the rows by parity gives ak(n)=Uk(⌈n/2⌉) Uk(⌊n/2⌋)a_k(n)=U_k(\lceil n/2\rceil)\,U_k(\lfloor n/2\rfloor), where Uk(m)U_k(m) counts sequences in {0,…,m}k\{0,\dots,m\}^k in which every three consecutive entries (a,b,c)(a,b,c) satisfy b=cb=c or a≥max⁡(b,c)a\ge\max(b,c); equivalently, Uk(m)U_k(m) counts the multichains of length mm in a subposet Λk\Lambda_k of the Boolean lattice. We prove three main results. First, for each mm the minimal order of a linear recurrence in kk is exactly 3m+13m+1, and a unique factorization into blocks gives a positive double-sum formula for Uk(m)U_k(m) in terms of Stirling and rr-Stirling numbers. Second, the bivariate generating function is not D-finite, and every polynomial-coefficient recurrence that holds on a quadrant is a left multiple of the defining four-term recurrence; the same holds for an associated Stirling-type triangle N(k,q)N(k,q), and UU is not Stirling-like in the sense of Kauers. Third, the numerators hk(t)h_k(t) of ∑mUk(m)tm=hk(t)/(1−t)k+1\sum_mU_k(m)t^m=h_k(t)/(1-t)^{k+1}, analogues of the Eulerian polynomials, have only simple real zeros; equivalently, the chain polynomials of the posets Λk\Lambda_k are real-rooted, and the rows of NN are log-concave. We also determine all binomial shapes with nonnegative parameters in which Uk(m)U_k(m) is a single sum, and show that the near-diagonal entries N(k,k−d)N(k,k-d) are polynomials in kk starting exactly at k=2d+2k=2d+2. The reduction, the exact orders, the explicit formula, the non-D-finiteness, the description of the quadrant recurrences and the near-diagonal theorem are formalized in Lean 4 with Mathlib.

Primarily AI-generated textHuman understanding: some partsD-finite power seriesLean 4OEIS A207123Ore algebrasStirling numberschain polynomialsformal verificationpattern-avoiding arraysr-Stirling numbersreal-rootedness

math.CO — Combinatorics

Gallai's conjecture with two exceptional even vertices

Contributed by Idris Ali Shaik

Gallai conjectured that every connected finite simple graph on n vertices admits an edge partition into at most ⌈n/2⌉ simple paths. Botler and Sambinelli proved this when every even-degree vertex has at most three even neighbours. Fan, Hou and Zhou exempted one designated even vertex of positive degree and ensured that at least two paths ended there. Xie obtained the same endpoint conclusion for either of two adjacent designated even vertices, in separate partitions, when every other even vertex has at most three even neighbours. We prove that the same endpoint conclusion holds without requiring the two designated even vertices to be adjacent. Let F be the subgraph induced by the even-degree vertices of a connected finite simple graph G on n vertices, and let h and x be distinct vertices of F. Suppose every other vertex of F has degree at most three in F. Then for each of h and x there is an edge partition into at most ⌈n/2⌉ simple paths, at least two of which end at that vertex. Consequently, Gallai's bound holds whenever at most two vertices of F have degree greater than three. The two choices may use different partitions. We also obtain one partition with at least two paths ending at each member of the pair, using at most ⌊n/2⌋ + 1 paths. At odd order this is Gallai's bound. At even order the extra path can be necessary: K₄ minus an edge requires three paths when both degree-two vertices are prescribed. The ceiling and endpoint bounds are formalized in Lean 4 with Mathlib and registered as PALOMAR-2026-10-04-000006, version 1.

A mix of human-written and AI-generated textHuman understanding: all partsGallai's conjectureLean formalizationeven-degree verticesgraph theorypath decomposition

math.GT — Geometric Topology

Fixed-Level TQFT Transport of Marked Handleslide Coherence: Disjoint Cubes and a Three-Handle Pentagon

Contributed by Hao-Yu Sun

Fix an ordinary level K≥1K\geq1 and a fully specified family of pairwise disjoint positive handleslides on a compression body. The main question is how a literal geometric relation becomes a literal finite-level operator relation. We construct a finite reduced skein fibre and one normalized isomorphism $$ Q_{K,d}:\mathcal M_{K,d}\xrightarrow{\sim}\mathcal V^+_{K,d} $$ to the corresponding scalar-extended Walker--TQFT state space. Reusing this map at every vertex sends the supplied weight-zero slide cylinders to EKE_K-linear automorphisms: geometric squares become operator squares, finite slide orders give the same operator, and forward/reverse maps telescope for all declared phases and integer weights. The construction is fibrewise and makes no comparison between levels. These operator relations are transported images of the geometric relations proved in Papers~1 and~2; they are not new geometric coherence theorems. We then treat a fully specified positive three-handle pentagon. Its vertex-zero compression body admits a compatible fixed-level comparison core: a rational disk-kernel cap, a normalized complementary handlebody, a reduced spine model, and one universal-construction isomorphism QK,dq:MK,dq→∼VK,d+Q_{K,d}^{\mathfrak q}:\mathcal M_{K,d}^{\mathfrak q}\xrightarrow{\sim}\mathcal V^+_{K,d}. The geometric weight-zero Walker pentagon consequently has a literal operator image over EKE_K, with explicit inverse formulas and a fixed-basis matrix corollary. Different comparison cores are related by a typed comparison groupoid and give intertwined operator systems; no canonical comparison or literal equality between different coordinate choices is asserted.

A mix of human-written and AI-generated textHuman understanding: some partsanomaly normalizationfixed-level transporthandleslide coherenceskein moduletopological quantum field theory

math.GT — Geometric Topology

Integral tail signatures and the Hilbert--Smith conjecture

Contributed by Alexander Dabrowski

The obstruction to an effective pp-adic manifold action is an integer signature tail. On asymptotically controlled rational modules over one fixed free CpC_p-space, finite-cover Mayer--Vietoris makes the difference between pp copies and quotient-permutation tensoring nilpotent. Every degree-four class therefore has eventually pp-divisible signatures. An effective action gives a class of signature 11: coordinate averaging provides degree-one sphere control, free sheets turn quotient representatives into a compatible homotopy idempotent, and its normalized Poincar\'e corner forgets to a scalar manifold germ. Successive localization boundaries recover one copy of $\CP^2$, up to sign. The resulting contradiction proves the Hilbert--Smith conjecture.

Primarily AI-generated textHuman understanding: some partsHilbert–Smith conjectureHilbert’s fifth problemLie groupsalgebraic L-theorycontrolled topologylocally compact groupsp-adic group actionssignaturestransformation groups

math.GM — General Mathematics

Linchpin Theorems

Contributed by Thomas Hales

A proof assistant checks a formal proposition. It does not check that the proposition expresses the mathematics that its author intended. This distinction becomes pressing when large bodies of mathematics are autoformalized. We propose the use of linchpin theorems: statements whose meanings can be audited with relatively little mathematical infrastructure, and whose proofs connect them to substantial results. Examples range from sphere packing and the classification of Lie algebras to regularity theory, the Weil conjectures, and computational complexity.

Primarily AI-generated textHuman understanding: some parts

math.OA — Operator Algebras

Noncommutative Maccone-Pati Uncertainty Principles

Contributed by K. MAHESH KRISHNA

Let E\mathcal{E} be a Hilbert C*-module over a unital C*-algebra A\mathcal{A}. Let A:D(A)⊆E→EA: \mathcal{D}(A) \subseteq \mathcal{E} \to \mathcal{E} and B:D(B)⊆E→EB: \mathcal{D}(B)\subseteq \mathcal{E}\to \mathcal{E} be possibly unbounded self-adjoint morphisms. Then for all x∈D(AB)∩D(BA)x \in \mathcal{D}(AB)\cap \mathcal{D}(BA) with ⟨x,x⟩=1\langle x, x \rangle =1, we show that \begin{align*} (1) \quad\quad\quad d_x(A)^2+d_x(B)^2&\geq \mp \langle \{A,B\}x, x \rangle +\langle (A\pm B)x, y \rangle\langle y, (A\pm B)x \rangle\pm \{\langle Ax, x \rangle, \langle Bx, x \rangle\}, \\ &\quad \forall y \in \mathcal{E} \text{ satisfying } \|y\|\leq 1 \text{ and } \langle x,y \rangle =0 \end{align*} \begin{align*} (2) \quad \quad \quad d_x(A)^2+d_x(B)^2&\geq \mp i\langle [A,B]x, x \rangle +\langle (A\pm iB)x, y \rangle\langle y, (A\pm iB)x \rangle \mp i[\langle Ax, x \rangle, \langle Bx, x \rangle], \\ &\quad \forall y \in \mathcal{E} \text{ satisfying } \|y\|\leq 1 \text{ and } \langle x,y \rangle =0. \end{align*} where \begin{align*} & d_x(A):= \sqrt{\langle Ax, Ax \rangle -\langle Ax, x \rangle^2},\quad [A,B] := AB-BA, \\ & [\langle Ax, x \rangle,\langle Bx, x \rangle]:= \langle Ax, x \rangle\langle Bx, x \rangle -\langle Bx, x \rangle\langle Ax, x \rangle. \end{align*} We call Inequalities (1) and (2) as noncommutative Maccone-Pati uncertainty principles. They reduce to uncertainty principles derived by Maccone and Pati [\textit{Phys. Rev. Lett., 2014}] whenever A=C\mathcal{A}=\mathbb{C}.

Primarily human-written textHuman understanding: all partsHilbert C*-module.Uncertainty Principle

math.NT — Number Theory

Almost all Markoff numbers are unique.

Contributed by William Y. Chen

A Markoff number is the largest coordinate of a positive integer solution of a2+b2+c2=3abca^2+b^2+c^2=3abc. Frobenius conjectured in 1913 that every Markoff number is the largest coordinate of exactly one such solution with a≤b≤ca\le b\le c. We prove that the conjecture holds for almost all Markoff numbers: the proportion of exceptions among the Markoff numbers up to XX tends to 00 as X→∞X\to\infty. Two such solutions with the same largest coordinate give simple closed geodesics of equal length on the modular torus, that is, primitive homology classes v,wv,w with equal values N(v)=N(w)N(v)=N(w) of the McShane--Rivin stable norm NN. Estimates for the boundary of the unit ball of NN reduce the problem to the equations N(Gv)=N(v)N(Gv)=N(v) with GG a rational linear map. For each GG that is not a symmetry of the torus, a zero-one law for the 33-adic analytic dynamics of the mapping class group on the Markoff surface shows that the solutions vv have density zero.

Primarily AI-generated textHuman understanding: some partsMarkoff triplesmapping class group dynamicspunctured torus

math.NT — Number Theory

One of β(4), β(6),..., β(36) is irrational

Contributed by Shawn Krisman

Let β(s)=∑m≥0(−1)m(2m+1)−s\beta(s)=\sum_{m\ge 0}(-1)^m(2m+1)^{-s} be Dirichlet's beta function. We prove that at least one of the seventeen numbers β(4),β(6),…,β(36)\beta(4),\beta(6),\dots,\beta(36) is irrational. All previous explicit results of this kind that we know of include β(2)\beta(2), Catalan's constant; our statement does not involve β(2)\beta(2) at all. The proof uses the linear forms Ln=∑t≥0(−1)tRn′′(t)L_n=\sum_{t\ge0}(-1)^tR_n''(t) attached to a very-well-poised rational function RnR_n with triple integer zeros and half-integer poles. The second derivative, a β\beta-analogue of a device of Rivoal, removes β(2)\beta(2), and a symmetry removes the odd values. The zeros of RnR_n run through the region of its poles, which makes every prime p>np>n harmless. The common denominators are controlled by a pp-adic analysis and an arithmetic integral that we bound with an exact rational certificate. The size of LnL_n is bounded by an elementary estimate on the real axis, and its nonvanishing for infinitely many nn follows from a saddle-point analysis along a certified contour. The whole proof, including every numerical certificate, has been formalised in Lean 4 with Mathlib and checked by the Lean kernel, using only Lean's three standard axioms.

Primarily AI-generated textHuman understanding: no partsDirichlet beta functionLeanformal verificationirrationalitylinear forms in zeta-type valuessaddle-point method

math.NT — Number Theory

Finite Valuation Words and Terminal Obstructions for the Accelerated Syracuse Map

Contributed by Tosho Karadzhov

We develop a finite-word obstruction framework for the accelerated Syracuse map on positive odd integers. A finite valuation word determines an exact iterate formula and a unique realization class modulo a power of two; compatible infinite prefixes define a natural two-adic inverse-limit object together with least positive representatives. The first part records the exact finite-word congruence machinery, finite-descent equivalence, terminal-surplus identity, terminal-ceiling break criterion, bad-prefix windows, activated density collapse, stabilization criterion, and strict-jump bookkeeping. The second part uses these tools to isolate terminal obstruction classes for a hypothetical counterexample: a bounded branch leading to a nontrivial accelerated cycle, and an unbounded eventual no-jump branch, successively reduced through a chain of geometric and combinatorial normal forms to a packet-surplus compensation target. The resulting reduction spine is lossless: Collatz follows from exclusion of nontrivial accelerated cycles together with a packet-surplus, or stronger record-ladder, compensation theorem for the unbounded branch. As a closed module, we include a closed class-exclusion theorem showing that no eventually periodic infinite low-surplus valuation chain is realized by a positive odd integer. On the bounded branch, we further record, as an explicit unproved roadmap step, that the terminal-ceiling strict-jump obstruction reduces to a single recurrent valuation-mismatch statement. This manuscript proves the architecture stated in its theorems, propositions, lemmas, and corollaries; it states the remaining terminal exclusions explicitly as problems, conjectures, or roadmap steps, and does not claim a completed proof of the full Collatz conjecture.

Primarily AI-generated textHuman understanding: no parts3x+1 problemCollatz conjectureaccelerated Syracuse maplow-surplus chainsterminal obstructionsvaluation words

math.QA — Quantum Algebra

A fourteen-dimensional biperfect Lie bialgebra

Contributed by Pavel I Etingof

We construct a fourteen-dimensional Lie bialgebra for which both the underlying Lie algebra and its dual are perfect. The construction is defined over Q\mathbb{Q} and is self-dual over C\mathbb{C}. It gives an affirmative answer to Question 4.1(3) of Etingof--Gelaki--Guralnick--Saxl, arXiv:9912068. Its twenty-eight-dimensional Drinfeld double is quasitriangular with injective cobracket, also answering Question 4.1(4).

Primarily AI-generated textHuman understanding: some partsLie bialgebrasPoisson-Lie groups

math.GR — Group Theory

A universal group with thirteen relators

Contributed by Qiuyu Ren

We construct a finitely presented group with 13 relators that contains an isomorphic copy of every finitely presented group. This improves Valiev's bound of 21 relators for universal groups. The proof combines Valiev's construction, subgroup calculations of Kegel--Li--Ren, and small-cancellation theory.

Primarily AI-generated textHuman understanding: some partsfinitely presented groupuniversal group

math.NT — Number Theory

An elliptic curve of rank ≥34\geq 34 and root number −1-1 over a quadratic field

Contributed by Dylan T. Costa, Alvaro Lozano-Robledo

In this article, we find a quadratic twist over Q\mathbb{Q} of rank ≥2\geq 2 (and ≥3\geq 3 assuming parity) of an elliptic curve E/QE/\mathbb{Q} of rank ≥32\geq 32, recently found by Elkies, Klagsbrun, and Li. We use a family of quadratic twists of rank ≥2\geq 2 over Q(t)\mathbb{Q}(t) constructed by Mestre to search for twists EDE^D with root number −1-1, computing all root numbers without factoring the (very large) twisting parameter DD. As a result, we exhibit an explicit integer DD, with 411411 digits (a square times an integer with 381381 digits), such that EDE^D has root number −1-1 and two independent rational points. In particular, the rank of EE over Q(D)\mathbb{Q}(\sqrt{D}) is at least 3434, unconditionally, and at least 3535 if we assume the Parity Conjecture.

A mix of human-written and AI-generated textHuman understanding: all partselliptic curveparity conjecturequadratic fieldrank

math.NT — Number Theory

Rational Fourth Powers Summing to 82

Contributed by Natanael Wildner Fraga

We prove that the only primitive positive integer solutions of x4+y4=82z4x^4+y^4=82z^4 are (1,3,1)(1,3,1) and (3,1,1)(3,1,1). An arithmetic reduction lifts every other putative solution to an elliptic curve over K=Q(41,2)K=\mathbb{Q}(\sqrt{41},\sqrt{2}). An explicit 2-descent determines its rank as 3. A logarithmic functional then excludes all nonzero parameters in the relevant 2-adic disc, including both relative sign patterns at the two places above 2. The same argument determines every point of the auxiliary quartic whose parameter is rational: only the two points at infinity occur. Exact square identities also determine the quotient modulo 2, prove that the displayed subgroup has odd index, and give the vanishing of the 2-primary part of the Tate–Shafarevich group. Two reductions determine the torsion. The finite arithmetic certificates are supplied in two self-contained Python programs; no height cutoff or conjectural rank computation is used.

Primarily AI-generated textHuman understanding: no parts2-Descentbiquadratic fieldselliptic Chabautygeneralised Fermat equationrational fourth powers

math.NT — Number Theory

The P\'olya--Vinogradov inequality with log⁡log⁡q\log\log q

Contributed by Deep Bhattacharjee, Ushashi Bhattacharya

We prove unconditionally that every primitive Dirichlet character χ\chi modulo q≥3q\ge3 has character sums of size at most Cqlog⁡log⁡qC\sqrt q\log\log q. Montgomery and Vaughan proved this bound under the generalised Riemann hypothesis, and Paley showed that it is optimal. The proof uses the zero-free half-plane ℜs>7/8\Re s>7/8, which also gives ∣L′/L(1,χ)∣≪log⁡log⁡q|L'/L(1,\chi)|\ll\log\log q and two-sided bounds for the Euler--Kronecker constants of the cyclotomic fields Q(ζq)\mathbb Q(\zeta_q).

A mix of human-written and AI-generated textHuman understanding: some partsEuler--Kronecker constantsP\'olya--Vinogradov inequalitySelberg sievecharacter sumszero-free regions

math.NT — Number Theory

The Willow Transform and the Blind Zone Theorem: A Sharp Information-Theoretic Obstruction in the Turán Hierarchy for the Riemann xi-Function

Contributed by Changxia Lin

Let Xi(t) = xi(1/2 + it) be the Riemann Xi-function, let Xi(t) = sum_{k>=0} (-1)^k c_k t^{2k} be its even Taylor expansion at the origin, and let D(n,r) = det[c_{n+i-j}] (i,j = 0..r-1) be the Toeplitz minors whose positivity for all n >= 0, r >= 1 is equivalent to the Riemann Hypothesis (RH). We prove a sharp and quantitative obstruction in the resulting hierarchy of criteria. Parametrising the zeros of G(z) = sum c_k z^k by beta_j = -1/z_j, we establish by the dual Jacobi-Trudi identity the exact identity D(n,r) = s_{(r^n)}(beta), the Schur function of the rectangular partition (r^n) in the variables beta. A zero of zeta off the critical line contributes to beta a conjugate pair rho e^{+-i theta} whose angle theta is exactly the vertical angle of the violating pair of zeros, while zeros on the critical line contribute positive real variables. For two variables we prove the closed form s_{(a,b)}(rho e^{i theta}, rho e^{-i theta}) = rho^{a+b} sin((a+1-b) theta) / sin theta = rho^{a+b} U_{a-b}(cos theta), U_k being the Chebyshev polynomial of the second kind, so that the sign is governed by the classical criterion U_k(cos theta) > 0 if and only if (k+1) theta < pi. Since a Schur function in two variables can be expanded through the coproduct s_lambda(X sqcup Y) = sum_mu s_mu(X) s_{lambda/mu}(Y), and since s_mu(X) > 0 for positive real X, positivity reduces to the two-variable factors, whose index k = a - b is bounded by the number of columns r, not by the shift n. This yields: Blind Zone Theorem. If a violating pair subtends a vertical angle theta < pi/(r+1), then every Toeplitz minor D(n,r') with r' <= r is strictly positive, notwithstanding the presence of non-real zeros. The critical strip together with gamma_1 = 14.134725141... forces theta <= theta_max = 2 arctan(1/(2 gamma_1)) = 0.07071826... rad, whence pi/theta_max = 44.424... and therefore every order r <= 43 is completely non-discriminating. We emphasise that the exponential bound is on the order r and not on the shift n; we exhibit the mechanism and show the contrary n-based bound is false. We also record the refutation of a "universal covering law" previously conjectured by the author, and a floating-point artefact that nearly produced a false refutation of the main theorem. No claim of a proof of RH is made.

A mix of human-written and AI-generated textHuman understanding: all partsChebyshev polynomialsRiemann Zeta FunctionSchur functionsToeplitz minorsTuran inequalitiesblind zonetotal positivityxi-function

math.CO — Combinatorics

Linear Trace-Deficit Decay for Permanents of Positive Semidefinite Contractions

Contributed by Matěj Kripner, Václav Rozhoň, Robert Šámal, Martin Šindelář, Adrián Zámečník

Every Hermitian positive semidefinite contraction AA satisfies per⁡(A)≤exp⁡(−tr⁡(I−A)/68)\operatorname{per}(A)\leq\exp(-\operatorname{tr}(I-A)/68). This proves the linear trace-deficit bound conjectured by Ebrahimnejad, Nagda, and Oveis Gharan, whose estimate had quadratic dependence on the normalized deficit. The proof combines a size-biased complex Gaussian representation, a block version of Hanson–Wright decoupling, and a rational Loewner majorant. The constant is uniform in the dimension and is not optimized.

Primarily AI-generated textHuman understanding: some partsGaussian representationmatrix inequalitiespositive semidefinite permanenttrace deficit

math.IT — Information Theory

A finite-delay code for lexicographic graph products

Contributed by Matěj Kripner, Václav Rozhoň, Robert Šámal, Martin Šindelář, Adrián Zámečník

For all finite simple graphs, the strong product and both ordered lexicographic products have the same Shannon capacity, answering a question of Sason. An explicit code conversion delays one component by a single block, with rate loss tending to zero. The equality extends to arbitrary mixtures of the two products and survives adjoining an additional strong-product factor.

Primarily AI-generated textHuman understanding: some partsShannon capacitylexicographic productstrong productzero-error codes

math.MG — Metric Geometry

Sharp fractional Helly bounds for common affine flats

Contributed by Matěj Kripner, Václav Rozhoň, Robert Šámal, Martin Šindelář, Adrián Zámečník

If an α\alpha fraction of the (d−k+1)(d-k+1)-tuples of closed convex sets in Rd\mathbb R^d have an intersection containing a whole affine kk-flat, then a fraction 1−(1−α)1/(d−k+1)1-(1-\alpha)^{1/(d-k+1)} of the sets share such a flat. This coefficient is best possible, resolving the sharp fractional De Santis question of Ludwigson and Soberón. The geometric result behind the bound is (d−k)(d-k)-collapsibility of the common-flat complex, proved by coordinating convex sweeps in varying quotient spaces.

Primarily AI-generated textHuman understanding: some partsLeray complexesaffine flatsfractional Hellysharp bounds

math.RA — Rings and Algebras

The rank-one Dixmier conjecture for elements of mass at most six

Contributed by Idris Ali Shaik

Let K be a field of characteristic zero and let P,Q in A_1(K) satisfy [Q,P]=1. We prove that P,Q generate A_1(K) if either has mass at most six, meaning at most six nonzero homogeneous components for the grading deg X=1, deg Y=-1, with no degree bound on either element. This extends the four-component theorem of Guccione, Guccione and Valqui. The proof combines their Newton-polygon restrictions with a classification of polynomial pairs r,f satisfying an associated scalar differential equation under the condition that r^2 has at most six monomial terms. The scalar argument uses a two-dimensional Vandermonde kernel, Rolle's theorem, and a sign and parity obstruction. The scalar classification and the mass bound reduce the crossing cases to a binomial-power face. We exclude that face using at most one Newton cut, without a mass bound on the transformed pair. We also exclude a family of pure-power crossing faces with prime outer exponent, without a mass bound. A seven-term scalar solution shows that the scalar classification is sharp, although its associated Weyl face is excluded by the pure-power theorem. Theorem 1.1 is formalized in Lean 4 and registered as Palomar entry PALOMAR-2026-10-05-000006, version 2.

A mix of human-written and AI-generated textHuman understanding: all partsDixmier conjectureNewton polygonWeyl algebrahomogeneous componentssparse polynomials

cs.DS — Data Structures and Algorithms

Diameter-Free Pointwise Gaussian KDE in Near-Additive Query Time

Contributed by Matěj Kripner, Václav Rozhoň, Robert Šámal, Martin Šindelář, Adrián Zámečník

Wagner asked whether Gaussian kernel density estimation in Rd\mathbb R^d admits query time O~(d+ε−2)\widetilde O(d+\varepsilon^{-2}) without dependence on the diameter of the data. We answer this affirmatively for each fixed query: a randomized data structure answers a query to additive error ε\varepsilon with probability 1−δ1-\delta in time O((d+ε−2)log⁡(d+1)log⁡(2/δ))O((d+\varepsilon^{-2})\log(d+1)\log(2/\delta)), independently of the number of data points and of their diameter. The key ingredient is a variance bound for a Fastfood-type structured Fourier block that holds uniformly in the norm of the displacement.

Primarily AI-generated textHuman understanding: some partsFastfoodGaussian kernel density estimationpointwise approximationrandom Fourier featuresstructured random features

math.RT — Representation Theory

Finite Projective Source Geometry for GL2: Abel Resolvents and Central-Jet Degree Laws

Contributed by Shawn Schafer

Starting from the two trace functions p1 = Tr(A) and p2 = Tr(A^2) for semisimple A in GL2(C), we develop the associated projective source geometry. The coordinate y = t^2/d - 1 identifies the adjoint character, and normalized Haar measure on a specified closed subgroup H of SO(3) pushes forward to a probability measure nu_H. We describe this measure through harmonic multiplicities, moments, and its Stieltjes transform, and prove that it determines H up to conjugacy within the closed-subgroup class of SO(3). A positive Abel kernel resums the projective character tower and gives a resolvent formula whose endpoint limit recovers the mass of the identity atom. We give explicit Abel transforms for the finite rotation groups and positive-dimensional benchmark sources, and derive a finite-image Frobenius-prime Abel limit from Chebotarev. For central-jet interpolation, we prove two exact degree laws: the cyclic-versus-torus minimum degree is max(n, M+1), while the normalized tetrahedral detector against S4 and A5 has minimum degree 3 for M = 1, 2 and M+2 for M >= 3. We also compute the integral image of the tetrahedral averaging functional, obtaining 2Z for every M >= 2. All results are stated with their hypotheses. The paper does not claim a general infinite-spectrum Beyond Endoscopy trace formula or transfer of central-jet vanishing to orbital kernels.

Primarily AI-generated textHuman understanding: some partsAbel resolventsChebotarev density theoremGL2PGL2character measurescharacter theorycompact subgroups of SO(3)finite rotation groupspolynomial interpolationprojective characters

cs.DM — Discrete Mathematics

Fractional DAG treewidth controls DAG treewidth: profile reorientation and VC-dimension rounding

Contributed by Matěj Kripner, Václav Rozhoň, Robert Šámal, Martin Šindelář, Adrián Zámečník

For a nonempty finite graph, let FF be its fractional DAG treewidth, maximized over all acyclic orientations. Its DAG treewidth is at most 160F3ln⁡(16F)160F^3\ln(16F). This answers the boundedness question of Bressan, Lanzinger, and Roth. Reorienting the graph converts shattered source profiles into projective-plane obstructions, which bound their VC dimension by 5F25F^2. Classical epsilon-net rounding then converts fractional bag covers to integral ones without changing the decomposition.

Primarily AI-generated textHuman understanding: some partsDAG treewidthVC dimensionepsilon netsfractional hypertreewidthgraph homomorphisms

math.CO — Combinatorics

The Coloured Sand Theorem: the p-part of the sandpile group of the Hamming graph, for every prime p dividing q and every dimension d

Contributed by Rafael Amichis Luengo

Let H(d,q)=KqdH(d,q)=K_q^{d} be the Hamming graph and K(H(d,q))K(H(d,q)) its sandpile group (critical group, Jacobian). For primes p∤qp\nmid q its pp-part was determined by Jacobson, Niedermaier and Reiner in 2003, who wrote that the other primes appear "to be difficult, due to bad behavior of its pp-primary structure". We determine the Sylow pp-subgroup of K(H(d,q))K(H(d,q)) for every prime pp dividing qq and every dd, by an explicit rule. After the splitting of Jacobson, Niedermaier and Reiner, the group is a sum of cokernels of operators q(c+H)+Uq(c+H)+U on the Boolean lattice (Theorem A). These split over the indecomposable tilting modules T(λ)T(\lambda) of SL2SL_2 in characteristic pp that occur in a tensor power of the natural module. The contribution of T(λ)T(\lambda) consists of explicit small cyclic factors and of 2∣I∣2^{|I|} large ones, where II is the set of positions of the nonzero base-pp digits of λ+1\lambda+1 below the leading one. The large ones are obtained by pooling explicit integers, built from binomial valuations and base-pp carries, into a non-increasing sequence (Theorems I and J). The proof writes down explicit Zp\mathbb{Z}_p-lattices for all tilting modules of SL2SL_2, one move per base-pp digit; it reduces each contribution to the Smith form of an explicit 2∣I∣×2∣I∣2^{|I|}\times2^{|I|} matrix, and computes that form as in our proof for the hypercube (The Dancing Sand Theorem), the case p=2p=2. We also give closed formulas that need no pooling: for p>dp>d with ballot numbers (B), for the exponent with every prime (C), and for the number of cyclic factors (D). This proves Conjecture I of version 3 of this paper. Every result of the paper, Theorems A–J, is checked in Lean 4 with Mathlib, for every prime, and the Lean project was rebuilt from its sources on GitHub's machines, on Mathlib's published build. This work has not been refereed by a human expert.

Primarily AI-generated textHuman understanding: some partsHamming graphLean 4Smith normal formcritical groupsandpile grouptilting modules

math.DS — Dynamical Systems

Stable algebraic families of polarized dynamical systems and exceptional extensions

Contributed by Zhuchao Ji

The notion of exceptional maps in arbitrary dimension was recently introduced by Ji, Song, and Xie. In this paper, we introduce exceptional extensions of polarized dynamical systems: a family of systems admitting a positive-dimensional exceptional factor whose generic fiber dynamics have simultaneous local product coordinates with an isotrivial system. We then prove that an algebraic family of polarized endomorphisms of normal projective varieties over a quasi-projective curve is JJ-stable on a nonempty Zariski open subset if and only if it is isotrivial or it is an exceptional extension after a finite base change. This extends McMullen's theorem for stable algebraic families of rational maps to higher dimension. One ingredient is inspired by Ji and Xie's proof of McMullen's theorem: the use of homoclinic orbits and the multipliers of adjoint periodic points to control local return maps. The new ingredients are a higher-dimensional algebraization method and an inductive rigidity argument for the fiber dynamics, which together yield the exceptional extension structure.

Primarily AI-generated textHuman understanding: some partsComplex Dynamics; Arithmetic Dynamics

math.MG — Metric Geometry

Separated distances in fixed dimension

Contributed by John Tripodo

A finite Euclidean point set is distance-separated if the lengths of any two distinct unordered edges differ by at least one. Counting gives a diameter lower bound of binom(n,2), whereas Erdős asked for a lower bound with leading term n^2. We give two constructions in fixed dimension. For every 0 < epsilon <= 1/2, put m0 = ceil(8192/epsilon). For every n >= 4m0 there is a distance-separated n-point set in dimension 10m0-1 with diameter < (1/2+epsilon)n^2. A six-cluster construction gives arbitrarily large configurations in R^29 with diameter < 0.998n^2, and an explicit prime-interval bound gives diameter < 0.999n^2 for every n >= 400000. The constructions use two orthogonal circle families to control distances within and between clusters separately. Their common geometric argument reduces to a uniform operator estimate for the first result and three rational positive-definiteness certificates for the second. Lean 4 formalizations accompany the tolerance family and the dimension-29 result for arbitrarily large sizes; the all-size corollary is a written consequence.

Primarily AI-generated textHuman understanding: no partsErdős Problem 670Lean 4fixed dimensionseparated Euclidean distances