Zeros in Amplitudes: Gauge Theory and Radiation Interference

Abstract
It is found that any complete single-photon tree amplitude has a general canonical form which vanishes in certain kinematical zones provided that any derivative couplings are as prescribed by gauge theory. The location of these zones depends only on the external charges and momenta. Their occurrence is based on classical radiation interference that is a generalization of the well-known absence of dipole radiation by colliding particles with the same charge-to-mass ratio. Weak-boson amplitude zeros are explained.