Quasinormal Modes of Near-Extremal Black Holes and Black Strings in Massive Gravity Background

TL;DR

This paper computes quasinormal modes of near-extremal black holes and strings in massive gravity using numerical methods, confirming analytic formulas and exploring implications for the Strong Cosmic Censorship conjecture.

Contribution

It introduces and applies two numerical methods to accurately calculate QNMs in massive gravity backgrounds, validating analytic approximations and analyzing cosmic censorship.

Findings

Numerical results confirm the accuracy of the P"{o}schl-Teller potential approximation.

Analytic formulas effectively describe QNMs in near-extremal black holes.

Results have implications for the Strong Cosmic Censorship conjecture.

Abstract

Two numerical methods are used to calculate quasinormal modes (QNMs) of near-extremal black holes/strings in the generalized spherically/cylindrically symmetric background, the Asymptotic Iteration Method (AIM) and the Spectral Method. The numerical results confirm the accuracy of the approximate analytic formula using the P\"{o}schl-Teller potential. Our analytic formula is used to investigate the Strong Cosmic Censorship conjecture of extremal and near-extremal black holes in Ref. \cite{Burikham:2020dfi}.