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arXiv · 2401.12401

Exploring magnetic fluctuations effects in QED gauge fields: implications for mass generation

Jorge David Castaño-Yepes·Enrique Muñoz
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Abstract

In this work, we calculate the one-loop contribution to the polarization tensor for photons (and gluons) in the presence of a classical background magnetic field with white-noise stochastic fluctuations. The magnetic field fluctuations are incorporated into the fermion propagator in a quasi-particle picture, which we developed in previous works using the {\it replica trick}. By focusing on the strong-field limit, here we explicitly calculate the polarization tensor. Our results reveal that it does not satisfy the transversality conditions outlined by the Ward identity, thus breaking the $U(1)$ symmetry. As a consequence, in the limit of vanishing photon four-momenta, the tensor coefficients indicate the emergence of an effective magnetic mass induced on photons (and gluons) by these stochastic fluctuations, leading to the interpretation of a dispersive medium with a noise-dependent index of refraction.

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Jorge David Castaño-Yepes, Enrique Muñoz. 2024-01-22. Exploring magnetic fluctuations effects in QED gauge fields: implications for mass generation. https://arxiv.org/abs/2401.12401

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