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arXiv · hep-th/9907044

Recursive Graphical Construction for Feynman Diagrams of Quantum Electrodynamics

M. Bachmann·H. Kleinert·A. Pelster
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Abstract

We present a method for a recursive graphical construction of Feynman diagrams with their correct multiplicities in quantum electrodynamics. The method is first applied to find all diagrams contributing to the vacuum energy from which all n-point functions are derived by functional differentiation with respect to electron and photon propagators, and to the interaction. Basis for our construction is a functional differential equation obeyed by the vacuum energy when considered as a functional of the free propagators and the interaction. Our method does not employ external sources in contrast to traditional approaches.

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M. Bachmann, H. Kleinert, A. Pelster. 1999-12-08. Recursive Graphical Construction for Feynman Diagrams of Quantum Electrodynamics. https://doi.org/10.1103/physrevd.61.085017

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