SU(N) group-theory constraints on color-ordered five-point amplitudes at all loop orders
Color-ordered amplitudes for the scattering of n particles in the adjoint representation of SU(N) gauge theory satisfy constraints arising solely from group theory. We derive these constraints for n=.5 at all loop orders using an iterative approach. These constraints generalize well-known tree-level and one-loop group theory relations. © 2012 Elsevier B.V.
