High Energy Theory Seminar

We present an on-shell framework for addressing the self-force expansion around plane wave backgrounds. We first review these exact solutions in general relativity and their relation to the two-body problem via the Penrose limit. Then, we show how classical observables containing resumed post-Minkowskian (PM) contributions can be evaluated from the classical limit of scattering amplitudes on a plane wave background. As a concrete example of such an observable, we analyse the impulse and scattering waveform in the self-force expansion. Interestingly, by taking the weak field limit, we find that this framework naturally predicts the existence of contributions from non-vanishing perturbative 3-point amplitudes on Minkowski and with real kinematics. We solve this apparent conundrum by showing how these amplitudes can actually contribute to classical observables once large gauge transformations are taken into account.

In person attendees (469 Lauritsen) must have a valid Caltech ID.

Contact [email protected] for Zoom information.