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MiS Preprint
7/2014
Perturbative description of the fermionic projector: normalization, causality and Furry's theorem
Felix Finster and Jürgen Tolksdorf
Abstract
The causal perturbation expansion of the fermionic projector is performed with a contour integral method. Different normalization conditions are analyzed. It is shown that the corresponding light-cone expansions are causal in the sense that they only involve bounded line integrals. For the resulting loop diagrams we prove a generalized Furry theorem.
