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arXiv:2610.22548

A thermally and perturbatively stable classical spin model in two dimensions

Shankar Balasubramanian, Margarita Davydova, Ting-Chun Lin, Ryan Thorngren

quant-phcond-mat.stat-mechcs.ITmath-phSubmitted Oct 15, 2026• Announced Oct 19, 2026• 0 citations
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Abstract

We show that the 2D classical spin model constructed in arXiv:2605.10943 hosts many metastable states at non-zero temperature which are stable to arbitrary Hamiltonian perturbations, providing the first such example. Our proof relies on a recursive application of the cluster expansion.
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64 pages, 6 figures

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