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arXiv · 1908.09842

Strong Cosmic Censorship in Horndeski Theory

Kyriakos Destounis·Rodrigo D. B. Fontana·Filipe C. Mena·Eleftherios Papantonopoulos
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Abstract

The strong cosmic censorship hypothesis has recently regained a lot of attention in charged and rotating black holes immersed in de Sitter space. Although the picture seems to be clearly leaning towards the validity of the hypothesis in Kerr-de Sitter geometries, Reissner-Nordström-de Sitter black holes appear to be serious counter-examples. Here, we perform another test to the hypothesis by using a scalar field perturbation non-minimally coupled to the Einstein tensor propagating on Reissner-Nordström-de Sitter spacetimes. Such non-minimal derivative coupling is characteristic of Horndeski scalar-tensor theories. Although the introduction of higher-order derivative couplings in the energy-momentum tensor increases the regularity requirements for the existence of weak solutions beyond the Cauchy horizon, we are still able to find a small finite region in the black hole's parameter space where strong cosmic censorship is violated.

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Kyriakos Destounis, Rodrigo D. B. Fontana, Filipe C. Mena, Eleftherios Papantonopoulos. 2019-10-16. Strong Cosmic Censorship in Horndeski Theory. https://doi.org/10.1007/jhep10(2019)280

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