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arXiv · 1811.06854

Computing Black Hole Entropy at Infinity

Freya Edholm·Edi Halyo
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Abstract

We show that the entropy of asymptotically flat, nonextremal black holes can be computed at infinity. We provide a prescription for transforming these black holes to $AdS_2$ black holes with the same entropy by dimensional reduction to 2D and a Weyl transformation. We apply our prescription to Schwarzschild, 4D Reissner--Nordstrom and generic nonextremal black holes. In the transformed coordinates, the asymptotic regions contain a global $AdS_2$ whose entropy can be computed either as the holographic entanglement entropy or as the entanglement entropy of a pair of Rindler $AdS_2$ spaces in the thermofield double state. This precisely reproduces the entropy of the original nonextremal black holes.

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Freya Edholm, Edi Halyo. 2018-11-15. Computing Black Hole Entropy at Infinity. https://arxiv.org/abs/1811.06854

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