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arXiv · 1607.05729

Diagrammatic Cancellations and the Gauge Dependence of QED

Henry Kißler·Dirk Kreimer
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Abstract

This letter examines diagrammatic cancellations for Quantum Electrodynamics (QED) in the general linear gauge. These cancellations combine Feynman graphs of various topologies and provide a method to reconstruct the gauge dependence of the electron propagator from the result of a particular gauge by means of a linear Dyson-Schwinger equation. We use this method in combination with dimensional regularization to demonstrate how the 3-loop $ε$-expansion in the Feynman gauge determines the $ε$-expansions for all gauge parameter dependent terms to 4 loops.

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Henry Kißler, Dirk Kreimer. 2016-12-19. Diagrammatic Cancellations and the Gauge Dependence of QED. https://doi.org/10.1016/j.physletb.2016.11.052

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