Dynamics of perturbations of rotating black holes

TL;DR

This paper numerically studies how perturbations evolve around rotating black holes, revealing how black hole spin influences gravitational wave signals during black hole mergers.

Contribution

It introduces a numerical method for solving the Teukolsky equation that captures its hyperbolic structure and analyzes the impact of black hole rotation on gravitational wave scattering.

Findings

Black hole rotation affects gravitational wave scattering.

The numerical method effectively models perturbation evolution.

Results help interpret gravitational wave signals from black hole mergers.

Abstract

We present a numerical study of the time evolution of perturbations of rotating black holes. The solutions are obtained by integrating the Teukolsky equation written as a first-order in time, coupled system of equations, in a form that explicitly captures its hyperbolic structure. We address the numerical difficulties of solving the equation in its original form. We follow the propagation of generic initial data through the burst, quasinormal ringing and power-law tail phases. In particular, we calculate the effects due to the rotation of the black hole on the scattering of incident gravitational wave pulses. These results may help explain how the angular momentum of the black hole affects the gravitational waves that are generated during the final stages of black hole coalescence.