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Black Hole Entropy from Loop Quantum Gravity

Carlo Rovelli
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Abstract

We argue that the statistical entropy relevant for the thermal interactions of a black hole with its surroundings is (the logarithm of) the number of quantum microstates of the hole which are distinguishable from the hole's exterior, and which correspond to a given hole's macroscopic configuration. We compute this number explicitly from first principles, for a Schwarzschild black hole, using nonperturbative quantum gravity in the loop representation. We obtain a black hole entropy proportional to the area, as in the Bekenstein-Hawking formula.

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Carlo Rovelli. 1996-03-30. Black Hole Entropy from Loop Quantum Gravity. https://doi.org/10.1103/physrevlett.77.3288

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