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arXiv · 2606.29404

A Multi-Body Dobrushin-Sokal Criterion -- Part II

Jan Philipp Neumann
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Abstract

We prove a sufficient condition for the absolute convergence of Mayer cluster expansions of log-partition and correlation functions applicable to lattice gases with possibly complex-valued multi-body interactions. Not only are several classical results subsumed but a partition scheme for spanning hypergraphs also makes our methods well-suited for treating stronger multi-body interactions, including higher-order hard-core repulsion in the context of hypergraph independence polynomials. Furthermore, our approach is easily combined with the Gruber--Kunz condition to produce extended convergence results for the polymer expansion of lattice gases, rivalling those obtained not too long ago by Nguyen and Fern\'andez (2024).

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Jan Philipp Neumann. 2026-06-28. A Multi-Body Dobrushin-Sokal Criterion -- Part II. https://arxiv.org/abs/2606.29404

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