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A Proof of the Generalized Second Law for Two-Dimensional Black Holes

Jeongwon Ho
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Abstract

We investigate the generalized second law for two-dimensional black holes in equilibrium (Hartle-Hawking) and nonequilibrium (Unruh) with the heat bath surrounding the black holes. We obtain a simple expression for the change of total entropy in terms of covariant thermodynamic variables, which is valid not only for the Hartle-Hawking state but also for the Unruh state up to leading order, without assuming a quasi-stationary evolution of the black holes. Using this expression, it is shown that the rate of local entropy production is non-negative in the two-dimensional black hole systems.

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Jeongwon Ho. 2001-04-25. A Proof of the Generalized Second Law for Two-Dimensional Black Holes. https://doi.org/10.1103/physrevd.64.064019

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