The Perturbation Spectrum of Black Holes in N=8 Supergravity

TL;DR

This paper calculates the perturbation spectra of four- and five-dimensional N=8 supergravity black holes using group theory and explicit decoupling methods, relating results to brane configurations and string theory.

Contribution

It introduces a group theoretical approach to compute black hole perturbation spectra in N=8 supergravity and extends previous N=4 results to five dimensions.

Findings

Perturbation spectrum for 4D black holes derived using SU(2) x USp(6) symmetry.

Explicit spectrum calculation for 5D black holes via decoupling equations.

Comparison of spectra with string theory predictions.

Abstract

The near horizon geometry of four-dimensional black holes in the dilute gas regime is AdS_3 x S^2, and the global symmetry group is SU(2) x USp(6). This is exploited to calculate their perturbation spectrum using group theoretical methods. The result is interpreted in terms of three extreme M5-branes, orthogonally intersecting over a common string. We also consider N=8 black holes in five dimensions, and compute the spectrum by explicit decoupling of the equations of motion, extending recent work on N=4 black holes. This result is interpreted in terms of D1- and D5-branes that are wrapped on a small four-torus. The spectra are compared with string theory.