Quasinormal ringing on the brane

TL;DR

This paper investigates the nonlinear gravitational effects of black holes on a brane by analyzing quasinormal modes, revealing that these modes follow the black hole entropy and may not distinguish between brane and lower-dimensional black holes.

Contribution

It provides an analytical study of brane-localized black hole quasinormal modes and their relation to black hole entropy, offering insights into nonlinear gravitational effects in braneworld models.

Findings

Quasinormal modes follow the entropy of the black hole.

Scattering problems may not distinguish between brane and lower-dimensional black holes.

Black hole quasinormal modes can reflect background geometry effects.

Abstract

While the linear behavior of gravity in braneworld models is well understood, much less is known about full non-linear gravitational effects. Even when they agree at the linear level, these could be expected to distinguish braneworlds from a lower-dimensional theory with no brane. Black holes are a good testing ground for such studies, as they are nonlinear solutions that would be expected to reflect the background geometry. In particular, we assess the role of black hole quasinormal modes in gravitational experiments devised to be sensitive to the existence of the brane, in a lower-dimensional setting where we have analytical control. We compute quasinormal modes of brane-localized black holes and find that they follow the entropy of the corresponding black hole. This observation allows us to conclude that, surprisingly, the scattering problem we consider, at least in some regimes, does not distinguish between non-linear gravitational effects of black holes in AdS space with a brane and black holes in a spacetime of one lower dimension.