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arXiv · 2505.20403

Casimir effect in critical $\mathrm{O}(N)$ models from non-equilibrium Monte Carlo simulations

Andrea Bulgarelli·Michele Caselle·Alessandro Nada·Marco Panero
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Abstract

$\mathrm{O}(N)$ vector models in three dimensions, when defined in a geometry with a compact direction and tuned to criticality, exhibit long-range fluctuations which induce a Casimir effect. The strength of the resulting interaction is encoded in the excess free-energy density, which depends on a universal coefficient: the Casimir amplitude. We present a high-precision numerical calculation of the latter, by means of a novel non-equilibrium Monte Carlo algorithm, and compare our findings with results obtained from large-$N$ expansions and from the conformal bootstrap.

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Andrea Bulgarelli, Michele Caselle, Alessandro Nada, Marco Panero. 2025-05-26. Casimir effect in critical $\mathrm{O}(N)$ models from non-equilibrium Monte Carlo simulations. https://doi.org/10.1103/lcvl-dgv4

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