Quasinormal resonances of a charged scalar field in a charged Reissner-Nordström black hole spacetime: A WKB analysis

Abstract

The fundamental quasinormal resonances of charged Reissner-Nordström black holes due to charged scalar perturbations are derived {\it analytically}. In the WKB regime, $qQ\gg\hbar$, we obtain a simple expression for the fundamental quasinormal resonances: $ω=qQ/r_+-i2πT_{\text{BH}}(n+{1 \over 2})$, where $T_{\text{BH}}$ and $Q$ are the temperature and electric charge of the black hole and $q$ is the electric charge of the field. Remarkably, our results show that the relaxation dynamics of a perturbed Reissner-Nordström black hole may saturate the recently proposed universal relaxation bound.

5 pages. arXiv admin note: text overlap with arXiv:1109.4080