Black Hole Entropy and Physics at Planckian Scales

V. Frolov

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arXiv · hep-th/9510156

Black Hole Entropy and Physics at Planckian Scales

V. Frolov

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Abstract

We discuss and compare different definitions of the entropy of a black hole. In particular we show that the thermodynamical entropy defined by the response of the free energy of a black hole to the change of temperature does not coincide with the statistical-mechanical entropy, obtained by counting its dynamical degrees of freedom. The no-boundary wavefunction of a black hole, its relation to the entropy problem and its generalization are discussed. We discuss the relation between on-shell and off-shell calculations of the entropy, and the role of the renormalization of the gravitational constant.

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V. Frolov. 1995-10-23. Black Hole Entropy and Physics at Planckian Scales. https://arxiv.org/abs/hep-th/9510156

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