Unitary transformation approach to quantum electrodynamics

Summary

A unitary transformation, representing a rotation in the Minkowski space, is introduced to decompose the electron-photon interactionH into two partsH ₁ andH ₂, and these are used in the perturbation calculation of electron self-energy and radiative corrections to the electron scattering amplitude. The ultraviolet divergences, appearing in the contributions fromH ₁ andH ₂ in the any order of perturbation, are shown to be cancelled with each other in the stage of matrix elements without integrating explicitly. This way of removing divergences should be distinguished from that in the traditional renormalization theory, since we do not need such a physiological concept of infinite theoretical mass or charge assumed in the latter theory.