The box diagram in Yukawa theory
arXiv:hep-th/0610309 · doi:10.1103/PhysRevD.75.065010
Abstract
We present a light-front calculation of the box diagram in Yukawa theory. The covariant box diagram is finite for the case of spin-1/2 constituents exchanging spin-0 particles. In light-front dynamics, however, individual time-ordered diagrams are divergent. We analyze the corresponding light-front singularities and show the equivalence between the light-front and covariant results by taming the singularities.
21 pages, 17 figures. submittes to Phys. Rev. D