# Strong Cosmic Censorship in Charged de Sitter spacetime with Scalar Field Non-minimally Coupled to Curvature

## TL;DR

This paper investigates how a non-minimally coupled scalar field affects the stability and cosmic censorship in charged de Sitter black holes, revealing conditions under which the censorship can be violated or preserved.

## Contribution

It demonstrates that non-minimal coupling influences the stability and cosmic censorship violation thresholds in RN-dS black holes, especially regarding the parameter beta and the cosmological constant.

## Key findings

- Negative coupling leads to instability; non-negative coupling stabilizes.
- Increasing coupling raises the critical charge ratio for censorship violation.
- Higher cosmological constant suppresses the increase in critical charge ratio.

## Abstract

We examine the stability and the strong cosmic censorship in the Reissner-Nordstrom-de Sitter (RN-dS) black hole by investigating the evolution of a scalar field non-minimally coupled to the curvature. We find that when the coupling parameter is negative, the RN-dS black hole experiences instability. The instability disappears when the coupling parameter becomes non-negative. With the increase of the coupling parameter, the violation of the strong cosmic censorship occurs at a larger critical charge ratio. But such an increase of the critical charge is suppressed by the increase of the cosmological constant. Different from the minimal coupling situation, it is possible to accommodate $\beta\ge1$ in the near extremal black hole when the scalar field is non-minimally coupled to curvature. The increase of the cosmological constant can allow $\beta\ge1$ to be satisfied for even smaller value of the coupling parameter. The existence of $\beta\ge1$ implies that the resulting curvature can continuously cross the Cauchy horizon.