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arXiv · 2404.04805

Logarithmic singularities of Renyi entropy as a sign of chaos?

Norihiro Iizuka·Mitsuhiro Nishida
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Abstract

We propose that the logarithmic singularities of the Renyi entropy of local-operator-excited states for replica index $n$ can be a sign of quantum chaos. As concrete examples, we analyze the logarithmic singularities of the Renyi entropy in various two-dimensional conformal field theories. We show that there are always logarithmic singularities of the Renyi entropy in holographic CFTs, but no such singularities in free and rational CFTs. These singularities of the Renyi entropy are also related to the logarithmic time growth of the Renyi entropy at late times.

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Norihiro Iizuka, Mitsuhiro Nishida. 2024-04-07. Logarithmic singularities of Renyi entropy as a sign of chaos?. https://arxiv.org/abs/2404.04805

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