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arXiv · 2304.07319

Scrambling is Necessary but Not Sufficient for Chaos

Neil Dowling·Pavel Kos·Kavan Modi
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Abstract

We show that out-of-time-order correlators (OTOCs) constitute a probe for Local-Operator Entanglement (LOE). There is strong evidence that a volumetric growth of LOE is a faithful dynamical indicator of quantum chaos, while OTOC decay corresponds to operator scrambling, often conflated with chaos. We show that rapid OTOC decay is a necessary but not sufficient condition for linear (chaotic) growth of the LOE entropy. We analytically support our results through wide classes of local-circuit models of many-body dynamics, including both integrable and non-integrable dual-unitary circuits. We show sufficient conditions under which local dynamics leads to an equivalence of scrambling and chaos.

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Neil Dowling, Pavel Kos, Kavan Modi. 2023-04-14. Scrambling is Necessary but Not Sufficient for Chaos. https://doi.org/10.1103/physrevlett.131.180403

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