Exact quasinormal modes for a special class of black holes

TL;DR

This paper derives exact analytical expressions for the quasinormal modes of scalar and electromagnetic perturbations in a specific class of higher-dimensional black holes, revealing bounds on angular momentum related to black hole size.

Contribution

It provides the first exact formulas for quasinormal modes in this black hole class, linking black hole size to perturbation angular momentum bounds.

Findings

Quasinormal modes exist when angular momentum is within a size-dependent bound.

Perturbations become purely damped if the bound is not fulfilled.

Exact expressions are derived for higher-dimensional black holes.

Abstract

Analytic exact expressions for the quasinormal modes of scalar and electromagnetic perturbations around a special class of black holes are found in d\ge3 dimensions. It is shown that, the size of the black hole provides a bound for the angular momentum of the perturbation. Quasinormal modes appear when this bound is fulfilled, otherwise the excitations become purely damped.