(23.05.) An eikonal approach to gravitational scattering and waveforms
Carlo Heissenberg (Queen Mary University London)
23.05.2024 at 16:15
The classical limit of scattering amplitudes offers a convenient strategy to calculate gravitational-wave observables for binary processes in the post-Minkowskian (PM) regime, in which the two objects are far apart and interact weakly. In this talk I will discuss how the eikonal exponentiation offers a simple and conceptually transparent framework to exploit this connection and calculate key gravitational observables from amplitudes: the deflection angle for two-body encounters, energy and angular momentum losses, as well as the emitted gravitational waveform itself. In particular, I will focus on the next-to-leading PM correction to the asymptotic waveform in the low-frequency and small-velocity limits, and I will show how the choice of asymptotic BMS frame is crucial in order to compare the resulting amplitude-based waveform with the multipolar post-Newtonian (PN) one, finding agreement up to 3PN order.