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arXiv · 2301.01353

More on chaos at weak coupling

Rohit R. Kalloor·Adar Sharon
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Abstract

We discuss aspects of the quantum Lyapunov exponent $\lambda_L$ in theories with an exactly marginal SYK-like random interaction, where $\lambda_L$ can be computed as a continuous function of the interaction strength $\mathcal{J}$. In $1d$, we prove a conjecture from arXiv:2111.06108 which states that at small $\mathcal{J}$, $\lambda_L$ can be found by considering a specific limit of the four-point function in the decoupled theory. We then provide additional evidence for the $2d$ version of this conjecture by discussing new examples of Lyapunov exponents which can be computed at weak coupling.

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Rohit R. Kalloor, Adar Sharon. 2023-01-03. More on chaos at weak coupling. https://arxiv.org/abs/2301.01353

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