Records from the S-Matrix Marathon: Gravitational Physics from Scattering Amplitudes

TL;DR

This paper explains how classical gravitational phenomena can be derived from scattering amplitudes, highlighting recent methods and applications in black hole physics, gravitational waves, and astrophysics.

Contribution

It introduces new approaches connecting scattering amplitudes to classical gravity and black hole physics, including effective field theory and waveform predictions.

Findings

Derivation of classical GR effects from amplitudes

Application of worldline EFT in astrophysics

Predictions of gravitational waveforms

Abstract

These lecture notes explain how classical gravitational physics emerges from scattering amplitudes. We emphasize the role of different kinematic regimes in probing various aspects of bound and unbound problems, as illustrated by the Hydrogen atom example. Classical predictions of General Relativity, such as the Shapiro time delay and perihelion precession, emerge from these considerations. We also explain a number of recent approaches to probing black hole physics from the perspective of amplitudes, including applications of worldline effective field theory in astrophysics, predictions of gravitational waveforms, and the hierarchical three-body problem. These notes are based on a series of lectures held during the S-Matrix Marathon workshop at the Institute for Advanced Study on 11--22 March 2024.