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arXiv · 2607.13321

Worldline representation of multiloop amplitudes in quantum electrodynamics

Victor M. Banda Guzmán·Uwe Müller·Cristofer Nava Jacuinde·Christian Schubert·Carlos J. Servin Tomas
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Abstract

The worldline approach to quantum electrodynamics allows one to construct integral representations combining large numbers of Feynman diagrams. Here I review the state-of-the-art of a long-term effort to make this fact useful for actual multiloop calculations, such as of the scalar and spinor QED vacuum polarization functions and the electron anomalous magnetic moment. After a short historical introduction, and a discussion of the non-standard mathematical challenges involved, I focus on a recent calculation of the two-loop vacuum polarisation in scalar QED and some master integral formulas obtained in this context.

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Victor M. Banda Guzmán, Uwe Müller, Cristofer Nava Jacuinde, Christian Schubert, Carlos J. Servin Tomas. 2026-07-14. Worldline representation of multiloop amplitudes in quantum electrodynamics. https://arxiv.org/abs/2607.13321

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