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arXiv · 1812.10599

Quasi-homogeneous black hole thermodynamics

Hernando Quevedo·Maria N. Quevedo·Alberto Sanchez
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Abstract

Although the fundamental equations of ordinary thermodynamic systems are known to correspond to first-degree homogeneous functions, in the case of non-ordinary systems like black holes the corresponding fundamental equations are not homogeneous. We present several arguments, indicating that black holes should be described by means of quasi-homogeneous functions of degree different from one. In particular, we show that imposing the first-degree condition leads to contradictory results in thermodynamics and geometrothermodynamics of black holes. As a consequence, we show that in generalized gravity theories the coupling constants like the cosmological constant, the Born-Infeld parameter or the Gauss-Bonnet constant must be considered as thermodynamic variables.

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Hernando Quevedo, Maria N. Quevedo, Alberto Sanchez. 2018-12-27. Quasi-homogeneous black hole thermodynamics. https://doi.org/10.1140/epjc%2Fs10052-019-6745-0

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