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arXiv · 1403.7352

Entropy of isolated horizon from surface term of gravitational action

Cheng-Yong Zhang·Yu Tian·Xiao-Ning Wu·Shao-Jun Zhang
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Abstract

Starting from the surface term of gravitational action, one can construct a Virasoro algebra with central extension, with which the horizon entropy can be derived by using Cardy formula. This approach gives a new routine to calculate and interpret the horizon entropy. In this paper, we generalize this approach to a more general case, the isolated horizon, which contains non-stationary spacetimes beyond stationary ones. By imposing appropriate boundary conditions near the horizon, the full set of diffeomorphism is restricted to a subset where the corresponding Noether charges form a Virasoro algebra with central extension. Then by using the Cardy formula, we can derive the entropy of the isolated horizon.

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Cheng-Yong Zhang, Yu Tian, Xiao-Ning Wu, Shao-Jun Zhang. 2014-03-28. Entropy of isolated horizon from surface term of gravitational action. https://doi.org/10.1088/0264-9381/31/19/195002

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