Cancellation of energy-divergences in Coulomb gauge QCD

Abstract

In the Coulomb gauge of nonabelian gauge theories there are in general, in individual graphs, 'energy-divergences' on integrating over the loop energy variable for fixed loop momentum. These divergences are avoided in the Hamiltonian, phase-space formulation. But, even in this formulation, energy-divergences re-appear at 2-loop order. We show in an example how these cancel between graphs as a consequence of Ward identities.

Comments: 8 pages, 3 figures, revised version, two references added; accepted for publication in EPJC