Black-hole head-on collisions in higher dimensions

TL;DR

This paper presents numerical simulations of head-on black-hole collisions in higher-dimensional spacetimes, analyzing gravitational wave emission and comparing results with perturbative predictions across dimensions 4 to 10.

Contribution

It provides the first systematic numerical study of black-hole collisions in higher dimensions, exploring gravitational radiation and testing perturbation theory validity.

Findings

Gravitational wave emission increases with spacetime dimension.

Perturbation theory accurately predicts energy emission in extreme mass ratio cases.

Simulations reveal dimension-dependent features of black-hole collisions.

Abstract

The collision of black holes and the emission of gravitational radiation in higher-dimensional spacetimes are of interest in various research areas, including the gauge-gravity duality, the TeV gravity scenarios evoked for the explanation of the hierarchy problem, and the large-dimensionality limit of general relativity. We present numerical simulations of head-on collisions of nonspinning, unequal-mass black holes starting from rest in general relativity with $4 \leq D\leq 10$ spacetime dimensions. We compare the energy and linear momentum radiated in gravitational waves with perturbative predictions in the extreme mass ratio limit, demonstrating the strength and limitations of black-hole perturbation theory in this context.