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arXiv · 1810.01847

Black Hole Entropy and Soft Hair

Sasha Haco·Stephen W. Hawking·Malcolm J. Perry·Andrew Strominger
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Abstract

A set of infinitesimal ${\rm Virasoro_{\,L}}\otimes{\rm Virasoro_{\,R}}$ diffeomorphisms are presented which act non-trivially on the horizon of a generic Kerr black hole with spin J. The covariant phase space formalism provides a formula for the Virasoro charges as surface integrals on the horizon. Integrability and associativity of the charge algebra are shown to require the inclusion of `Wald-Zoupas' counterterms. A counterterm satisfying the known consistency requirement is constructed and yields central charges $c_L=c_R=12J$. Assuming the existence of a quantum Hilbert space on which these charges generate the symmetries, as well as the applicability of the Cardy formula, the central charges reproduce the macroscopic area-entropy law for generic Kerr black holes.

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Sasha Haco, Stephen W. Hawking, Malcolm J. Perry, Andrew Strominger. 2018-10-03. Black Hole Entropy and Soft Hair. https://doi.org/10.1007/jhep12(2018)098

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