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Black Hole Thermodynamics from Euclidean Horizon Constraints

S. Carlip
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Abstract

To explain black hole thermodynamics in quantum gravity, one must introduce constraints to ensure that a black hole is actually present. I show that for a large class of black holes, such ``horizon constraints'' allow the use of conformal field theory techniques to compute the density of states, reproducing the Bekenstein-Hawking entropy in a nearly model-independent manner. One standard string theory approach to black hole entropy arises as a special case, lending support to the claim that the mechanism may be ``universal.'' I argue that the relevant degrees of freedom are Goldstone-boson-like excitations arising from the weak breaking of symmetry by the constraints.

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S. Carlip. 2007-05-25. Black Hole Thermodynamics from Euclidean Horizon Constraints. https://doi.org/10.1103/physrevlett.99.021301

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