Graviton partial waves and causality in higher dimensions

TL;DR

This paper establishes bounds on deviations from General Relativity in higher-dimensional graviton interactions, using partial wave analysis and causality constraints to limit possible corrections at low energies.

Contribution

It introduces a method to compute SO(D-1) partial waves efficiently and derives new bounds on higher-spin corrections and holographic conformal theory parameters.

Findings

Graviton S-matrix closely aligns with General Relativity at low energies.

Derived bounds on higher-spin state masses M in D>=5 dimensions.

Provided new constraints on central charges in holographic conformal theories.

Abstract

Do gravitational interactions respect the basic principles of relativity and quantum mechanics? We show that any graviton S-matrix that satisfies these assumptions cannot significantly differ from General Relativity at low energies. We provide sharp bounds on the size of potential corrections in terms of the mass M of new higher-spin states, in spacetime dimensions D>=5 where the S-matrix does not suffer from infrared ambiguities. The key novel ingredient is the full set of SO(D-1) partial waves for this process, which we show how to efficiently compute with Young tableau manipulations. We record new bounds on the central charges of holographic conformal theories.