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arXiv · 1210.6736

Noether current of the surface term of Einstein-Hilbert action, Virasoro algebra and entropy

Bibhas Ranjan Majhi
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Abstract

A derivation of Noether current from the surface term of Einstein-Hilbert action is given. We show that the corresponding charge, calculated on the horizon, is related to the Bekenstein-Hawking entropy. Also using the charge, the same entropy is found based on the Virasoro algebra and Cardy formula approach. In this approach, the relevant diffeomorphisms are found by imposing a very simple physical argument: diffeomorphisms keep the horizon structure invariant. This complements similar earlier results (arXiv:1204.1422) obtained from York-Gibbons-Hawking surface term. Finally we discuss the technical simplicities and improvements over the earlier attempts and also various important physical implications.

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Bibhas Ranjan Majhi. 2012-10-27. Noether current of the surface term of Einstein-Hilbert action, Virasoro algebra and entropy. https://doi.org/10.1155/2013%2F386342

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