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arXiv · 2108.08544

Defect Extremal Surface for Reflected Entropy

Tianyi Li·Ma-Ke Yuan·Yang Zhou
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Abstract

Defect extremal surface is defined by extremizing the Ryu-Takayanagi formula corrected by the quantum defect theory. This is interesting when the AdS bulk contains a defect brane (or string). We introduce a defect extremal surface formula for reflected entropy, which is a mixed state generalization of entanglement entropy measure. Based on a decomposition procedure of an AdS bulk with a brane, we demonstrate the equivalence between defect extremal surface formula and island formula for reflected entropy in AdS$_3$/BCFT$_2$. We also compute the evolution of reflected entropy in evaporating black hole model and find that defect extremal surface formula agrees with island formula.

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hep-thcond-mat.str-elgr-qcquant-ph

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Tianyi Li, Ma-Ke Yuan, Yang Zhou. 2021-08-19. Defect Extremal Surface for Reflected Entropy. https://doi.org/10.1007/jhep01(2022)018

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