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Entropy and black hole horizons

J. G. Russo
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Abstract

The standard approach of counting the number of eigenmodes of $N$ scalar fields near the horizon is used as a basis to provide a simple statistical mechanical derivation of the black hole entropy in two and four dimensions. The Bekenstein formula $S={A\ov 4G\h}$ and the two-dimensional entropy $S=2M/ł\h $ are naturally obtained (up to a numerical constant of order 1). This approach provides an explanation on why the black hole entropy is of order $1/\h $ and why it is independent of the number of field-theoretical degrees of freedom.

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J. G. Russo. 1995-07-12. Entropy and black hole horizons. https://doi.org/10.1016/0370-2693(95)01020-q

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