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arXiv · 2207.11980

Onset of Quantum Chaos in Random Field Theories

Micha Berkooz·Adar Sharon·Navot Silberstein·Erez Y. Urbach
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Abstract

We study the quantum Lyapunov exponent $\lambda_L$ in theories with spacetime-independent disorder. We first derive self-consistency equations for the two- and four-point functions for products of $N$ models coupled by disorder at large $N$, generalizing the equations appearing in SYK-like models. We then study families of theories in which the disorder coupling is an exactly marginal deformation, allowing us to follow $\lambda_L$ from weak to strong coupling. We find interesting behaviors, including a discontinuous transition into chaos, mimicking classical KAM theory.

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Micha Berkooz, Adar Sharon, Navot Silberstein, Erez Y. Urbach. 2022-07-25. Onset of Quantum Chaos in Random Field Theories. https://doi.org/10.1103/physrevlett.129.071601

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