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arXiv · 2004.10139

Extremal cosmological black holes in Horndeski gravity and the anti-evaporation regime

Ismael Ayuso·Diego Sáez-Chillón Gómez
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Abstract

Extremal cosmological black holes are analysed in the framework of the most general second order scalar-tensor theory, the~so-called Horndeski gravity. Such~extremal black holes are a particular case of Schwarzschild-De Sitter black holes that arises when the black hole horizon and the cosmological one coincide. Such~metric is induced by a particular value of the effective cosmological constant and is known as Nariai spacetime. The~existence of this type of solutions is studied when considering the Horndeski Lagrangian and its stability is analysed, where the so-called anti-evaporation regime is studied. Contrary to other frameworks, the~radius of the horizon remains stable for some cases of the Horndeski Lagrangian when considering perturbations at linear order.

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Ismael Ayuso, Diego Sáez-Chillón Gómez. 2020-04-21. Extremal cosmological black holes in Horndeski gravity and the anti-evaporation regime. https://doi.org/10.3390/universe6110210

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