The Ultimate Matching Theorem

Primarily AI-generated textHuman understanding: some partsmath.PR — Probability

Contributed by Michael Goldman ↗, Francesco Grotto ↗, Dario Trevisan ↗

Version 1 / Nov 11, 2026 / CC BY 4.0

Abstract

Let X1,…,XNX_1,\dots,X_N be independent uniform points in the unit square, matched either to an evenly spread deterministic configuration or to a second independent sample. For exponents α1,α2>2\alpha_1,\alpha_2>2 with 1/α1+1/α2=1/21/\alpha_1+1/\alpha_2=1/2, we prove that with probability tending to one a single permutation controls the jjth coordinate displacements in the exponential Orlicz norm of exponent αj\alpha_j, at the scale log⁡N/N\sqrt{\log N/N}, for both j=1,2j=1,2. This settles Talagrand's Ultimate Matching Conjecture for all pairs of finite critical exponents. The proof constructs, on the flat torus, a current whose divergence is Gaussian white noise projected on a dyadic grid and whose coordinates have the critical anisotropic exponential Orlicz bounds, and transfers it to matching through a primal optimal-transport reduction. At the hard endpoints (2,∞)(2,\infty) and (∞,2)(\infty,2) the conjecture fails: a Brownian local-time construction shows that the normalized optimal matching cost diverges in probability.

Provenance statement

This work was largely generated and proof-checked by LLMs through a series of interactions aimed at understanding the initial version of GPT-6's solution to Talagrand's Ultimate Matching problem. That solution was itself developed through extensive interactions with the LLM, drawing also on the authors' ideas and previous work. GPT-6 also provided a sharper argument for the endpoint cases of the conjecture, which is available together with the initial version of the solution in the GitHub repository referenced in the preprint. The authors have an overall understanding of the proofs and intend to provide a fully digested version in the near future.

Tools used

OpenAI
ChatGPT
Anthropic
Claude Fable

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Version history

  1. v1 · 70 pagesSubmitted by Francesco GrottoInitial depositCurrentNov 10, 2026