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arXiv · 2008.07593

Thermodynamics of de Sitter Black Holes with Conformally Coupled Scalar Fields

Fil Simovic·Danny Fusco·Robert B. Mann
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Abstract

We investigate the thermodynamic properties of 3+1 dimensional black holes in asymptotically de Sitter spacetimes, conformally coupled to a real scalar field. We use a Euclidean action approach, where boundary value data is specified at a finite radius `cavity' outside the black hole, working in the extended phase space where the cosmological constant is treated as a thermodynamic pressure. We examine the phase structure of these black holes through their free energy. For the MTZ subclass of solutions, we find Hawking-Page-like phase transitions from a black hole spacetime to thermal de Sitter with a scalar field. In the more general case, Hawking-Page-like phase transitions are also present, whose existence depends further on a particular cosmic censorship bound.

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Fil Simovic, Danny Fusco, Robert B. Mann. 2020-08-17. Thermodynamics of de Sitter Black Holes with Conformally Coupled Scalar Fields. https://doi.org/10.1007/jhep02(2021)219

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