Strong Cosmic Censorship in Einstein-Maxwell-Scalar-Gauss-Bonnet Theory

TL;DR

This paper investigates whether the strong cosmic censorship conjecture holds in Einstein-Maxwell-Scalar-Gauss-Bonnet theory by analyzing scalar field perturbations and finds conditions under which SCC can be restored.

Contribution

It explores the impact of non-minimally coupled scalar fields on SCC in RNdS black holes within Einstein-Maxwell-Scalar-Gauss-Bonnet theory, revealing parameter regimes that restore SCC.

Findings

SCC can be recovered with certain parameters.

Non-minimal coupling affects the extendibility of the metric.

Quasinormal modes indicate stability conditions.

Abstract

Recently, it is found that the strong cosmic censorship (SCC) is violated in RNdS black hole by a minimal coupled neutral massless scalar field at the linear perturbation level. For the Einstein-Maxwell-Scalar-Gauss-Bonnet theory which is famous for the spontaneous scalarization phenomenon, there exists the scalar field coupled with the Gauss-Bonnet term. Whether the SCC of the RNdS black hole can be repaired by the non-minimal coupled scalar field perturbation at the linear level becomes an interesting question. In this paper, we firstly investigate the extendibility of the metric beyond the Cauchy horizon in the Einstein-Maxwell-Scalar-Gauss-Bonnet theory. Then, we examine the SCC of the RNdS black hole by calculating the quasinormal mode of the non-minimal coupled scalar field and find that the SCC can be recovered under some parameters.