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arXiv · hep-th/0311167

Two-Loop Diagrammatics in a Self-Dual Background

Gerald V. Dunne
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Abstract

Diagrammatic rules are developed for simplifying two-loop QED diagrams with propagators in a constant self-dual background field. This diagrammatic analysis, using dimensional regularization, is used to explain how the fully renormalized two-loop Euler-Heisenberg effective Lagrangian for QED in a self-dual background field is naturally expressed in terms of one-loop diagrams. The connection between the two-loop and one-loop vacuum diagrams in a background field parallels a corresponding connection for free vacuum diagrams, without a background field, which can be derived by simple algebraic manipulations. It also mirrors similar behavior recently found for two-loop amplitudes in N=4 SUSY Yang-Mills theory.

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Gerald V. Dunne. 2003-11-18. Two-Loop Diagrammatics in a Self-Dual Background. https://doi.org/10.1088/1126-6708%2F2004%2F02%2F013

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