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arXiv · 1607.06995

Perturbation Theory in Supersymmetric QED: Infrared Divergences and Gauge Invariance

Michael Dine·Patrick Draper·Howard E. Haber·Laurel Stephenson Haskins
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Abstract

We study some aspects of perturbation theory in $N=1$ supersymmetric abelian gauge theories with massive charged matter. In general gauges, infrared (IR) divergences and nonlocal behavior arise in 1PI diagrams, associated with a $1/k^4$ term in the propagator for the vector superfield. We examine this structure in supersymmetric QED. The IR divergences are gauge-dependent and must cancel in physical quantities like the electron pole mass. We demonstrate that cancellation takes place in a nontrivial way, amounting to a reorganization of the perturbative series from powers of $e^2$ to powers of $e$. We also show how these complications are avoided in cases where a Wilsonian effective action can be defined.

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Michael Dine, Patrick Draper, Howard E. Haber, Laurel Stephenson Haskins. 2016-07-24. Perturbation Theory in Supersymmetric QED: Infrared Divergences and Gauge Invariance. https://doi.org/10.1103/physrevd.94.095003

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