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arXiv · hep-th/9403158

Worldline Green Functions for Multiloop Diagrams

M. G. Schmidt·C. Schubert
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Abstract

We propose a multiloop generalization of the Bern-Kosower formalism, based on Strassler's approach of evaluating worldline path integrals by worldline Green functions. Those Green functions are explicitly constructed for the basic two-loop graph, and for a loop with an arbitrary number of propagator insertions. For scalar and abelian gauge theories, the resulting integral representations allow to combine whole classes of Feynman diagrams into compact expressions.

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M. G. Schmidt, C. Schubert. 1994-03-25. Worldline Green Functions for Multiloop Diagrams. https://doi.org/10.1016/0370-2693(94)90944-x

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