Corrections in the relative entropy of black hole microstates

Ben Michel; Andrea Puhm

doi:10.1007/jhep07(2018)179

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arXiv · 1801.02615

Corrections in the relative entropy of black hole microstates

Ben Michel·Andrea Puhm

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Abstract

Inspired by the recent work of Bao and Ooguri (BO), we study the distinguishability of the black hole microstates from the thermal state as captured by the average of their relative entropies: the Holevo information. Under the assumption that the vacuum conformal block dominates the entropy calculation, BO find that the average relative entropy vanishes on spatial regions less than half the size of the CFT. However, vacuum block dominance fails for some microstates of the $M=0$ BTZ black hole. We show that this renders the average relative entropy nonzero even on infinitesimal intervals at $O(c^0)$.

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Ben Michel, Andrea Puhm. 2018-01-08. Corrections in the relative entropy of black hole microstates. https://doi.org/10.1007/jhep07(2018)179

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