On the nullification of threshold amplitudes
arXiv:hep-th/0207010 · doi:10.1103/PhysRevD.66.105010
Abstract
The nullification of threshold amplitudes is considered within the conventional framework of quantum field theory. The relevant Ward identities for the reduced theory are derived both on path-integral and diagrammatic levels. They are then used to prove the vanishing of tree-graph threshold amplitudes.
16 pages