# Superradiance of a Global Monopole in Reissner-Nordstr\"{o}m(-AdS) Space-time

## TL;DR

This paper investigates how a global monopole influences superradiance and stability of Reissner-Nordström-AdS black holes under charged scalar perturbations, revealing that monopoles tend to stabilize these black holes against superradiance.

## Contribution

It provides an analytical and graphical study of superradiance phenomena in RN-AdS black holes with global monopoles, highlighting the monopole's stabilizing effect.

## Key findings

- Monopole charge alters superradiance threshold frequency.
- Global monopoles increase the stability of black holes against superradiance.
- The presence of monopoles affects the instability time scale.

## Abstract

In this article, the behaviour of a charged and massive scalar field around a global monopole swallowed by a Reissner-Nordstr\"{o}m-Anti-de Sitter (RN-AdS) black hole is investigated by considering the Klein-Gordon equation in this geometry. The superradiance phenomenon and instability behaviour of the black hole against charged scalar perturbations are studied for both an RN-AdS case and also for an RN black hole surrounded by a reflective mirror, i.e., the black hole bomb case. The effects of the monopole on these cases are discussed analytically and also with the help of several graphs in detail. The monopole charge affects the superradiance threshold frequency and also effects the instability time scale for both cases. The existence of global monopole makes these black holes more stable against superradiance instability.