Eur. Phys. J. C (2016) 76: 554
https://doi.org/10.1140/epjc/s10052-016-4384-2

Regular Article - Theoretical Physics

Unimodular trees versus Einstein trees

¹ Instituto de Física Teórica, IFT-UAM/CSIC, Universidad Autónoma, 28049, Madrid, Spain
² Departamento de Física Teórica, Universidad Autónoma de Madrid, 28049, Madrid, Spain
³ Departamento de Física Teórica I Facultad de Ciencias Físicas, Universidad Complutense de Madrid (UCM), Av. Complutense S/N (Ciudad Univ.), 28040, Madrid, Spain

^* e-mail: sergio.gonzalez.martin@csic.es

Received: 26 July 2016
Accepted: 15 September 2016
Published online: 12 October 2016

Abstract

The maximally helicity violating tree-level scattering amplitudes involving three, four or five gravitons are worked out in Unimodular Gravity. They are found to coincide with the corresponding amplitudes in General Relativity. This a remarkable result, insofar as both the propagators and the vertices are quite different in the two theories.