  We discuss the equivalence of the standard covariant expressions and
light-front expressions of the three fundamental one loop Feynman diagrams of
Quantum Electrodynamics viz. vertex correction, fermion self-energy and vacuum
polarization in the light-front gauge obtained using time-ordered Hamiltonian
perturbation theory. Although this issue has been addressed by us and others
previously, our emphasis in this article is to resolve any ambiguity regarding
the correct form of the gauge boson propagator to be used in the light-front
gauge. We show how integrating over the light-front energy consistently in the
covariant expression of each of the three one loop corrections leads to the
propagating as well as the instantaneous diagrams of the light-front theory. In
doing so, we re-establish the necessity of using the doubly transverse gauge
boson propagator.

High Energy Physics - Theory