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arXiv · 1306.5063

Entropy from near-horizon geometries of Killing horizons

Olaf Dreyer·Amit Ghosh·Avirup Ghosh
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Abstract

We derive black hole entropy based on the near-horizon symmetries of black hole space-times. To derive these symmetries we make use of an $(R,T)$-plane close to a Killing horizon. We identify a set of vector fields that preserves this plane and forms a Witt algebra. The corresponding algebra of Hamiltonians is shown to have a non-trivial central extension. Using the Cardy formula and the central charge we obtain the Bekenstein-Hawking entropy.

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Olaf Dreyer, Amit Ghosh, Avirup Ghosh. 2013-06-21. Entropy from near-horizon geometries of Killing horizons. https://doi.org/10.1103/physrevd.89.024035

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