Coherent states in null-plane QED.

Light front field theories are known to have the usual infra-red divergences of the equal time theories, as well as new ‘spurious’ infra-red divergences. The former kind of IR divergences are usually treated by giving a small mass to the gauge particle. An alternative method to deal with these divergences is to calculate the transition matrix elements in a coherent state basis. In this paper we present, as a model calculation, the lowest order correction to the three point vertex in QED using a coherent state basis in the light cone formalism. The relevant transition matrix element is shown to be free of the true IR divergences up to O(e2). Typeset using REVTEX 0