Quantum diffusion of magnetic fields in a numerical worldline approach
نویسندگان
چکیده
We propose a numerical technique for calculating effective actions of electromagnetic backgrounds based on the worldline formalism. As a conceptually simple example, we consider scalar electrodynamics in three dimensions to one-loop order. Beyond the constant-magneticfield case, serving as a benchmark test, we analyze the effective action of a step-function-like magnetic field – a configuration that is inaccessible to derivative expansions. We observe magnetic-field diffusion, i.e., nonvanishing magnetic action density at space points near the magnetic step where the classical field vanishes. ∗ Emmy Noether fellow PACS: 12.20.-m, 11.15.Ha keywords: worldline, effective action, Monte-Carlo simulation
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