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arXiv · 1906.00993

Instability of Super-Entropic Black Holes in Extended Thermodynamics

Clifford V. Johnson
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Abstract

The charged black hole of Banados, Teitelbiom and Zanelli is studied in extended gravitational thermodynamics where there is a dynamical pressure and volume. It is a simple example of a super-entropic black hole, violating the reverse isoperimetric inequality. It is proven that this property implies that its specific heat at constant volume is negative, signalling a new kind of fundamental instability for black holes. It is conjectured that this instability is present for other super-entropic black holes, and this is demonstrated numerically for a large family of known solutions.

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Clifford V. Johnson. 2019-06-03. Instability of Super-Entropic Black Holes in Extended Thermodynamics. https://doi.org/10.1142/s0217732320500984

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