Stability of Reissner-Nordström black hole in de Sitter background under charged scalar perturbation

Abstract

We find a newinstability in the four-dimensional Reissner-Nordström–de Sitter black holes against charged scalar perturbations with vanishing angular momentum, l ¼ 0. We show that such an instability is caused by superradiance. The instability does not occur for a larger angular index, as explicitly proved for l ¼ 1. Our results are obtained from a numerical investigation of the time-domain profiles of the perturbations