A recursion relation for gravity amplitudes

Abstract Britto, Cachazo and Feng have recently derived a recursion relation for tree-level scattering amplitudes in Yang–Mills. This relation has a bilinear structure inherited from factorisation on multi-particle poles of the scattering amplitudes—a rather generic feature of field theory. Motivated by this, we propose a new recursion relation for scattering amplitudes of gravitons at tree level. Using this, we derive a new general formula for the MHV tree-level scattering amplitude for n gravitons. Finally, we comment on the existence of recursion relations in general field theories.