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arXiv · 2307.10986

Local first law of black hole

Pabitra Tripathy·Pritam Nanda·Amit Ghosh
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Abstract

We investigated the form and implications of the local first law of black hole thermodynamics in relation to an observer located at a finite distance from the black hole horizon. Our study is based on the quasilocal form of the first law for black hole thermodynamics, given by $\delta E=\frac{\bar{\kappa}}{8\pi}\delta A$, where $\delta E$ and $\delta A$ represent the changes in the black hole mass and area, respectively, and $\bar{\kappa}$ denotes the quasilocal surface gravity. We show that even at a finite distance, the quasilocal law still holds. It shows how the first law scales with the observer's location.

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Pabitra Tripathy, Pritam Nanda, Amit Ghosh. 2023-07-20. Local first law of black hole. https://doi.org/10.1007/s10714-024-03243-7

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