Classical Gravitational Bremsstrahlung from a Worldline Quantum Field Theory

TL;DR

This paper employs a worldline quantum field theory approach to compute gravitational waveforms from black hole encounters, providing a more efficient method that could enhance predictions for high-velocity gravitational interactions.

Contribution

It introduces a novel application of worldline quantum field theory to calculate gravitational bremsstrahlung, reproduces known results efficiently, and extracts new angular momentum and energy data.

Findings

Reproduces Kovacs and Thorne's waveform results efficiently

Calculates total radiated angular momentum and energy at leading order

Potentially improves gravitational-wave predictions for high-velocity encounters

Abstract

Using the recently established formalism of a worldline quantum field theory (WQFT) description of the classical scattering of two spinless black holes, we compute the far-field time-domain waveform of the gravitational waves produced in the encounter at leading order in the post-Minkowskian (weak field, but generic velocity) expansion. We reproduce previous results of Kovacs and Thorne in a highly economic way. Then using the waveform we extract the leading-order total radiated angular momentum and energy (including differential results). Our work may enable crucial improvements of gravitational-wave predictions in the regime of large relative velocities.