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arXiv · 2608.28755

A Quasi-local Entropy for Black Hole Space-times

Raymond Isichei
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Abstract

We show that for static & spherically symmetric black hole geometries, the angular components of the Brown-York tensor on a finite radius boundary can be interpreted as the product of the Tolman-Ehrenfest temperature and a quasi-local entropy. This entropy vanishes at spatial infinity and monotonically increases as radius decreases, taking its maximum value on the horizon where it is equal to the Bekenstein-Hawking entropy. Thus, the behaviour of this entropy provides explicit verification of the covariant entropy conjecture.

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Raymond Isichei. 2026-08-28. A Quasi-local Entropy for Black Hole Space-times. https://arxiv.org/abs/2608.28755

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