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arXiv · 0906.2881

2PI functional techniques for gauge theories: QED

U. Reinosa·J. Serreau
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Abstract

We discuss the formulation of the prototype gauge field theory, QED, in the context of two-particle-irreducible (2PI) functional techniques with particular emphasis on the issues of renormalization and gauge symmetry. We show how to renormalize all $n$-point vertex functions of the (gauge-fixed) theory at any approximation order in the 2PI loop-expansion by properly adjusting a finite set of local counterterms consistent with the underlying gauge symmetry. The paper is divided in three parts: a self-contained presentation of the main results and their possible implementation for practical applications; a detailed analysis of ultraviolet divergences and their removal; a number of appendices collecting technical details.

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U. Reinosa, J. Serreau. 2009-06-16. 2PI functional techniques for gauge theories: QED. https://doi.org/10.1016/j.aop.2009.11.005

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