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arXiv · 2302.00157

Eigenstate Thermalization Hypothesis for Generalized Wigner Matrices

Abstract

In this paper, we extend results of Eigenvector Thermalization to the case of generalized Wigner matrices. Analytically, the central quantity of interest here are multiresolvent traces, such as $Λ_A:= \frac{1}{N} \text{Tr }{ GAGA}$. In the case of Wigner matrices, as in \cite{cipolloni-erdos-schroder-2021}, one can form a self-consistent equation for a single $Λ_A$. There are multiple difficulties extending this logic to the case of general covariances. The correlation structure prevents us from deriving a self-consistent equation for a single matrix $A$; this is due to the introduction of new terms that are quite distinct from the form of $Λ_A$. We find a way around this by carefully splitting these new terms and writing them as sums of $Λ_B$, for matrices $B$ obtained by modifying $A$ using the covariance matrix. The result is a system of self-consistent equations relating families of deterministic matrices. Our main effort in this work is to derive and analyze this system of self-consistent equations.

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BibTeXRIS

Arka Adhikari, Sofiia Dubova, Changji Xu, Jun Yin. 2023-02-16. Eigenstate Thermalization Hypothesis for Generalized Wigner Matrices. https://arxiv.org/abs/2302.00157

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