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arXiv · 2604.11876

Quantum Mpemba effect in chaotic systems with conservation laws

Thomas Martin Müller·Silvia Pappalardi·Rosario Fazio
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Abstract

Closed chaotic quantum systems relax after a quench into a Gibbs ensemble. At late times, the relaxation speed is determined by their conservation laws and hydrodynamics. As a result, there exist pairs of initial states which thermalize to the same ensemble, yet exhibit drastically different hydrodynamic relaxation. We show in two chaotic spin chains how this enables a simple and robust realization of the quantum Mpemba effect: a system initially closer to equilibrium relaxes slower than one that starts farther away, despite both approaching the same final state.

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Thomas Martin Müller, Silvia Pappalardi, Rosario Fazio. 2026-04-13. Quantum Mpemba effect in chaotic systems with conservation laws. https://doi.org/10.1103/8nhn-1rs1

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