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arXiv:2604.15720

Geometric entropy and time-like entanglement entropy on a rotating BTZ black hole

Huayu Dai, Xi-Hao Fang, Mitsutoshi Fujita A, Song He

Published Apr 17, 2026• 0 citations
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Abstract

In this paper, we analyze the double Wick rotation of a rotating BTZ black hole and the entanglement entropy. We derive the transition matrix dual to the double Wick-rotated BTZ black hole, which has the usual shape at an imaginary chemical potential. In the dual gravity side, the double Wick rotated BTZ black hole, which is obtained as a quotient, is equal to a rotating BTZ black hole after the coordinate transformation and the identification of periodicity. The geometric entropy and time-like entanglement entropy are reproduced by the identification. New Lorentzian entanglement growth is defined by the coefficient of linear growth of time-like entanglement entropy.

DOI
10.48550/arxiv.2604.15720

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