Perturbative Gravity from QCD Amplitudes

TL;DR

This paper shows how to derive a gravity Lagrangian from QCD gluon amplitudes using perturbative relations inspired by string theory, simplifying gravity calculations.

Contribution

It provides a method to construct gravity Lagrangians from QCD amplitudes and offers simpler tree-level Feynman rules for gravity.

Findings

Explicit construction for up to five-point interactions.

Simpler tree-level gravity Feynman rules.

Connection between gauge theory and gravity via squaring relations.

Abstract

We demonstrate that QCD gluon amplitudes can be used to construct a Lagrangian for gravity. This procedure makes use of perturbative `squaring' relations between gravity and gauge theory that follow from string theory. We explicitly carry out the construction for up to five-point interactions and discuss a set of field variables in the Einstein-Hilbert Lagrangian for interpreting the Lagrangian obtained from QCD. A spin-off from our analysis is that it can be used to provide simpler tree-level gravity Feynman rules than for conventional gauges.