Abstract
To understand how problems of self-interaction are to be addressed in quantum electrodynamics, we can start by analyzing a classical theory of the Dirac and electromagnetic fields. In such a classical field theory, the electron has a spread-out distribution of charge that avoids some problems of self-interaction facing point charge models. However, there remains the problem that the electron will experience self-repulsion. This self-repulsion cannot be eliminated within classical field theory, but it can be eliminated from quantum electrodynamics in the Coulomb gauge by fully normal-ordering the Coulomb term in the Hamiltonian.
