Regge Poles and anS-Matrix Theory of the Lamb Shift

Abstract

The Lamb shift in hydrogen is calculated by means of dispersion theory. Relativistic invariance is maintained throughout the calculation, and electron spin is included, although the spin of the proton is neglected. Divergence problems which have plagued other calculations are eliminated by the exploitation of the Regge behavior of the amplitudes which appear in the dispersion integrals. The preliminary results are in excellent agreement with the lowest-order values given by Yennie and Erickson.