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arXiv · 2506.09011

Eigenstate Thermalization Hypothesis and Random Matrix Theory Universality in Few-Body Systems

Jiaozi Wang·Hua Yan·Robin Steinigeweg·Jochen Gemmer
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Abstract

In this paper, we study the Feingold-Peres model as an example, which is a well-known paradigm of quantum chaos. Using semiclassical analysis and numerical simulations, we study the statistical properties of observables in few-body systems with chaotic classical limits and the emergence of random matrix theory universality. More specifically, we focus on: 1) the applicability of the eigenstate thermalization hypothesis in few-body systems and the dependence of its form on the effective Planck constant and 2) the existence of a universal random matrix theory description of observables when truncated to a small microcanonical energy window. Our results provide new insights into the established field of few-body quantum chaos and help bridge it to modern perspectives, such as the general eigenstate thermalization hypothesis (ETH).

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BibTeXRIS

Jiaozi Wang, Hua Yan, Robin Steinigeweg, Jochen Gemmer. 2025-06-10. Eigenstate Thermalization Hypothesis and Random Matrix Theory Universality in Few-Body Systems. https://doi.org/10.1103/94k1-8w3n

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