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arXiv · hep-ph/0112198

Loops and loop clouds - a numerical approach to the worldline formalism in QED -

Holger Gies·Kurt Langfeld
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Abstract

A numerical technique for calculating effective actions of electromagnetic backgrounds is proposed, which is based on the string-inspired worldline formalism. As examples, we consider scalar electrodynamics in three and four dimensions to one-loop order. Beyond the constant-magnetic-field case, we analyze a step-function-like magnetic field exhibiting a nonlocal and nonperturbative phenomenon: ``magnetic-field diffusion''. Finally, generalizations to fermionic loops and systems at finite temperature are discussed.

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Holger Gies, Kurt Langfeld. 2001-12-14. Loops and loop clouds - a numerical approach to the worldline formalism in QED -. https://doi.org/10.1142/s0217751x02010388

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