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arXiv · 2502.03533

Generic Hilbert Space Fragmentation in Kogut--Susskind Lattice Gauge Theories

Abstract

At the heart of quantum many-body physics lies the understanding of mechanisms that avoid quantum thermalization in an isolated system quenched far from equilibrium. A prominent example is Hilbert space fragmentation, which has recently emerged as an ergodicity-breaking mechanism in constrained spin models. Here, we show that Kogut--Susskind formulations of lattice gauge theories in $d+1$D ($d$ spatial and one temporal dimensions) give rise to Hilbert space fragmentation, and discuss possible implications for understanding continuum physics. Our findings not only prove that lattice gauge theories are a natural platform for Hilbert space fragmentation, they also serve as a guide to the conditions under which these models can be faithfully used to infer the thermalization properties of quantum chromodynamics.

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BibTeXRIS

Anthony N. Ciavarella, Christian W. Bauer, Jad C. Halimeh. 2025-10-20. Generic Hilbert Space Fragmentation in Kogut--Susskind Lattice Gauge Theories. https://arxiv.org/abs/2502.03533

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