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arXiv · 2609.08169

On overlap concentration in the Curie-Weiss Random Field model

Yutong Li·Juspreet Singh Sandhu·Jonathan Shi
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Abstract

We show that the overlaps of two independent replicas drawn from the Gibbs measure of the Curie--Weiss model with random field (CWRF) exhibit sub-Gaussian tails when the inverse temperature $ β< 1$ and the random field is drawn from a Gaussian distribution that makes the expected magnetization of the CWRF equal to its expected overlap in the thermodynamic limit. To show this, we prove finite-moment concentration via a rigorous Laplace approximation for a certain random rate function, and ``bootstrap'' it to a uniform bound for the moment-generating function of the squared overlap deviations using a sharp analysis of the associated rate function.

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Yutong Li, Juspreet Singh Sandhu, Jonathan Shi. 2026-09-08. On overlap concentration in the Curie-Weiss Random Field model. https://arxiv.org/abs/2609.08169

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