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arXiv · 2203.13145

Emergence of periodic in magnetic moment effective QED action

Stefan Evans·Johann Rafelski
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Abstract

We evaluate for the inhomogeneous static electric Sauter step potential the imaginary part of the emerging homogeneous in electric field effective Euler-Heisenberg-Schwinger action sourced by vacuum fluctuations of a charged particle with magnetic moment of arbitrary strength. The result is convergent for all values of gyromagnetic ratio $g$, periodic in $g$, with a cusp at $g=2$. We consider the relation to the QED beta-function which is also found to be periodic in $g$. We confirm presence of asymptotic freedom conditions using this novel method and document a wider range of $g$-values for which asymptotic freedom is present.

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Stefan Evans, Johann Rafelski. 2022-05-27. Emergence of periodic in magnetic moment effective QED action. https://doi.org/10.1016/j.physletb.2022.137190

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