Multiloop calculations in the string-inspired formalism: The single spinor loop in QED

We use the world line path-integral approach to the Bern-Kosower formalism for developing a new algorithm for the calculation of the sum of diagrams with one spinor loop and a fixed number of external and internal photons. The method is based on world line supersymmetry, and on the construction of generalized world line Green functions. The two-loop QED β function is calculated as an example. © 1996 The American Physical Society.