Gravitational waves from black hole emission

TL;DR

This paper explores potential gravitational wave signals from hypothetical black hole emission and absorption events, proposing modifications to waveform models to test deviations from general relativity in alternative theories of gravity.

Contribution

It introduces simple modifications to existing gravitational wave models to simulate signals from exotic black hole emission and absorption scenarios, aiding in testing GR.

Findings

Proposed waveform modifications for exotic black hole events

Initial simulations suggest detectable signatures in gravitational wave data

Framework for null tests of general relativity using these signals

Abstract

Using adiabatic point-particle black hole perturbation theory, we simulate plausible gravitational wave~(GW) signatures in two exotic scenarios (i) where a small black hole is emitted by a larger one ('black hole emission') and (ii) where a small black hole is emitted by a larger one and subsequently absorbed back ('black hole absorption'). While such scenarios are forbidden in general relativity!(GR), alternative theories (such as certain quantum gravity scenarios obeying the weak gravity conjecture, white holes, and Hawking radiation) may allow them. By leveraging the phenomenology of black hole emission and absorption signals, we introduce straightforward modifications to existing gravitational waveform models to mimic gravitational radiation associated with these exotic events. We anticipate that these (incomplete but) initial simulations, coupled with the adjusted waveform models, will aid in the development of null tests for GR using GWs.