Charged scalar perturbations around a regular magnetic black hole

TL;DR

This paper investigates how charged scalar fields behave around a regular magnetic black hole, finding that the black hole remains stable under such perturbations and that the scalar charge influences oscillation frequencies.

Contribution

It provides the first detailed analysis of charged scalar perturbations in a regular magnetic black hole background, highlighting stability and frequency shifts.

Findings

Charged scalar perturbations do not cause superradiance.

The scalar charge affects the real part of quasinormal frequencies.

The imaginary part of quasinormal frequencies remains largely unchanged.

Abstract

We study charged scalar perturbations in the background of a regular magnetic black hole. In this case, the charged scalar perturbation does not result in superradiance. By using careful time-domain analysis, we show that the charge of scalar field can change the real part of quasinormal frequency, but has little impact on the imaginary part of quasinormal frequency and the behavior of the late-time tail. Therefore, the regular magnetic black hole may be stable under the perturbations of charged scalar field at the linear level.