Amplitudes, Gravity and Classical Discontinuities

TL;DR

This paper explores the application of on-shell scattering amplitude methods to classical gravity problems, specifically light-bending and the vDVZ discontinuity, aiming to bridge particle physics techniques with astrophysical and cosmological contexts.

Contribution

It demonstrates how on-shell methods can be used to analyze classical gravity phenomena, providing new insights into longstanding issues like light-bending and the vDVZ discontinuity.

Findings

On-shell methods offer a novel perspective on classical gravity problems.

Revisiting light-bending with amplitude techniques yields new insights.

Analysis of the vDVZ discontinuity using modern amplitude methods.

Abstract

On-shell methods have revitalized interest in scattering amplitudes which have, in turn, shed some much needed light on the structure of quantum field theories. These developments have been warmly embraced by the particle physics community. Less so in the astrophyical and cosmological contexts. As part of an effort to address this imbalance, we illustrate these methods by revisiting two classic problems in gravity: gravitational light-bending and the vDVZ discontinuity of massive gravity.