Light-cone singularities in classical and quantum field theories with interaction

Abstract

It is shown that the light-cone singularity suggested by the SLAC experiment on deep inelastic electroproduction is already given by the singularity of the classical current-current Poisson bracket. The form of the latter turns out to be exactly the one proposed by Fritsch and Gell-Mann, only the fields constituting local and biolocal currents are modified by the interaction. Translating this result into quantum field theory we point out that anomalous singularities occurring in the field commutator cancel in the current commutator.