A Fully Numerical Approach to One-Loop Amplitudes

Abstract

We suggest a new approach for the automatic and fully numerical evaluation of one-loop scattering amplitudes in perturbative quantum field theory. We use suitably formulated dispersion relations to perform the calculation as a convolution of tree-level amplitudes. This allows to take advantage of the iterative numerical algorithms for the evaluation of leading order matrix elements.

Comments: 31 pages, revised and enlarged manuscript, axodraw.sty needed