Bifurcation of the Maxwell quasinormal spectrum on asymptotically anti-de Sitter black holes

TL;DR

This paper investigates how the Maxwell quasinormal spectrum behaves on asymptotically anti-de Sitter black holes, revealing a bifurcation phenomenon influenced by boundary conditions, black hole size, and monopole parameters.

Contribution

It demonstrates the bifurcation (mode split effect) of the Maxwell quasinormal spectrum under Robin boundary conditions on Schwarzschild-AdS black holes, including monopole effects.

Findings

Spectrum bifurcates with increasing black hole radius

Boundary conditions can trigger or terminate mode split

Monopole parameter influences spectrum bifurcation

Abstract

We study the Maxwell quasinormal spectrum on asymptotically anti-de Sitter black holes with a set of two Robin type boundary conditions, by requiring the energy flux to vanish at asymptotic infinity. Focusing, for illustrative purposes, on Schwarzschild-anti-de Sitter black holes both without and with a global monopole, we unveil that, on the one hand, the Maxwell quasinormal spectrum bifurcates as the black hole radius increases for both boundary conditions, which is termed the mode split effect; while on the other hand, with an appropriate fixed black hole radius but increasing the monopole parameter, the first (second) boundary condition may trigger (terminate) the mode split effect.