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arXiv · 2509.06551

Holographic Reflected Entropy: Islands and Defect Phases

Ankur Dey·Gautam Sengupta
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Abstract

We investigate the mixed state entanglement structure through the reflected entropy for disjoint radiation subsystems coupled to a 2d eternal brane world black hole in a time dependent defect AdS$_3$/BCFT$_2$ scenario. Utilizing the island prescription and the defect extremal surface (DES) formula, we demonstrate a complex mixed state entanglement structure through the reflected entropy corresponding to distinct entanglement entropy phases. In each case we verify the holographic duality of the reflected entropy with the bulk entanglement wedge cross section (EWCS) and also obtain the Page curves for both the entanglement entropy and the associated reflected entropy phases. Furthermore, we extend our analysis to adjacent radiation subsystems and obtain consistent results using both the island and the DES prescription.

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Ankur Dey, Gautam Sengupta. 2025-09-08. Holographic Reflected Entropy: Islands and Defect Phases. https://doi.org/10.1007/jhep12(2025)086

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