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arXiv · 2311.17023

Reflected entropy in BCFTs on a black hole background

Debarshi Basu·Himanshu Chourasiya·Vinayak Raj·Gautam Sengupta
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Abstract

We obtain the reflected entropy for bipartite mixed state configurations involving two disjoint and adjacent subsystems in two dimensional boundary conformal field theories (BCFT$_2$s) in a black hole background. The bulk dual is described by an AdS$_3$ black string geometry truncated by a Karch-Randall brane. The entanglement wedge cross section computed for this geometry matches with the reflected entropy obtained for the BCFT$_2$ verifying the holographic duality. In this context, we also obtain the analogues of the Page curves for the reflected entropy and investigate the behaviour of the Markov gap.

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Debarshi Basu, Himanshu Chourasiya, Vinayak Raj, Gautam Sengupta. 2023-11-28. Reflected entropy in BCFTs on a black hole background. https://doi.org/10.1007/jhep05(2024)054

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