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arXiv · 1802.04665

Near Horizon Symmetry and Entropy Formula for Kerr-Newman (A)dS Black Holes

M. R. Setare·H. Adami
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Abstract

In this paper we provide the first non-trivial evidence for universality of the entropy formula $4\pi J_{0}^{+}J_{0}^{-}$ beyond pure Einstein gravity in 4-dimensions. We consider the Einstein-Maxwell theory in the presence of cosmological constant, then write near horizon metric of the Kerr-Newman (A)dS black hole in the Gaussian null coordinate system. We consider near horizon fall-off conditions for metric and $U(1)$ gauge field. We find asymptotic combined symmetry generator, consists of diffeomorphism and $U(1)$ gauge transformation, so that it preserves fall-off conditions. Consequently, we find supertranslation, supperrotation and multiple-charge modes and then we show that the entropy formula is held for the Kerr-Newman (A)dS black hole. Supperrotation modes suffer from a problem. By introducing new combined symmetry generator, we cure that problem.

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M. R. Setare, H. Adami. 2018-02-12. Near Horizon Symmetry and Entropy Formula for Kerr-Newman (A)dS Black Holes. https://doi.org/10.1007/jhep04(2018)133

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