Hawking radiation and propagation of massive charged scalar field on a three-dimensional G\"{o}del black hole

TL;DR

This paper investigates Hawking radiation and scalar field propagation in a three-dimensional G"{o}del black hole, revealing superradiance, quasinormal mode instability, and unique absorption properties.

Contribution

It provides an analytical study of quasinormal modes and superradiance for scalar fields in a G"{o}del black hole, highlighting their instability and oscillatory behavior.

Findings

Scalar waves can be superradiantly amplified.

Quasinormal modes are unstable due to closed time-like curves.

Absorption cross section vanishes at high frequencies.

Abstract

In this paper we consider the three-dimensional G\"{o}del black hole as a background and we study the vector particle tunneling from this background in order to obtain the Hawking temperature. Then, we study the propagation of a massive charged scalar field and we find the quasinormal modes analytically, which turns out be unstable as a consequence of the existence of closed time-like curves. Also, we consider the flux at the horizon and at infinity, and we compute the reflection and transmission coefficients as well as the absorption cross section. Mainly, we show that massive charged scalar waves can be superradiantly amplified by the three-dimensional G\"{o}del black hole and that the coefficients have an oscillatory behavior. Moreover, the absorption cross section is null at the high frequency limit and for certain values of the frequency.