RENORMALIZATION THEORY

Standard renormalization theory is presented with the help of a new technique for handling the subtractions. Briefly, the approach used is to replace the subtraction of terms from the Feynman integrand by an equivalent set of differential and integral operations on the integrals. It is relatively straightforward to show that these operations lead to a unique finite part of every integral. Although we are concerned here primarily with the general analysis of renormalization theory to all orders of the perturbation expansion, the explicit calculation of individual terms in the expansion is straightforward, and certainly not more lengthy than in the usual approach. In this approach, it is a simple matter to demonstrate gauge invariance of the finite amplitudes without explicity carrying out the integrations; this contrasts with the usual treatment. © 1969.