SU(N) group-theory constraints on color-ordered five-point amplitudes at all loop orders

摘要

Color-ordered amplitudes for the scattering of n particles in the adjointrepresentation of SU(N) gauge theory satisfy constraints arising solely fromgroup theory. We derive these constraints for n=5 at all loop orders using aniterative approach. These constraints generalize well-known tree-level andone-loop group theory relations.