General Relativity from Scattering Amplitudes
Abstract
We outline the program to apply modern quantum field theory methods to calculate observables in classical general relativity through a truncation to classical terms of the multi-graviton two-body on-shell scattering amplitudes between massive fields. Since only long-distance interactions corresponding to non-analytic pieces need to be included, unitarity cuts provide substantial simplifications for both post-Newtonian and post-Minkowskian expansions. We illustrate this quantum field theoretic approach to classical general relativity by computing the interaction potentials to second order in the post-Newtonian expansion, as well as the scattering functions for two massive objects to second order in the post-Minkowskian expansion. We also derive an all-order exact result for gravitational light-by-light scattering.
Cite
@article{arxiv.1806.04920,
title = {General Relativity from Scattering Amplitudes},
author = {N. E. J. Bjerrum-Bohr and Poul H. Damgaard and Guido Festuccia and Ludovic Planté and Pierre Vanhove},
journal= {arXiv preprint arXiv:1806.04920},
year = {2018}
}
Comments
v2: 9 pages. Version to be published, minor corrections, references updated, and a new appendix on the eikonal method (a supplemental material at PRL)