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Flat Information Geometries in Black Hole Thermodynamics

J. E. Aman·Ingemar Bengtsson·Narit Pidokrajt
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Abstract

The Hessian of either the entropy or the energy function can be regarded as a metric on a Gibbs surface. For two parameter families of asymptotically flat black holes in arbitrary dimension one or the other of these metrics are flat, and the state space is a flat wedge. The mathematical reason for this is traced back to the scale invariance of the Einstein-Maxwell equations. The picture of state space that we obtain makes some properties such as the occurence of divergent specific heats transparent.

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J. E. Aman, Ingemar Bengtsson, Narit Pidokrajt. 2006-01-27. Flat Information Geometries in Black Hole Thermodynamics. https://doi.org/10.1007/s10714-006-0306-1

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