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arXiv · 2211.16985

QED Fermions in a noisy magnetic field background

Jorge David Castaño-Yepes·Marcelo Loewe·Enrique Muñoz·Juan C. Rojas·Renato Zamora
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Abstract

We consider the effects of a noisy magnetic field background over the fermion propagator in QED, as an approximation to the spatial inhomogeneities that would naturally arise in certain physical scenarios, such as heavy-ion collisions or the quark-gluon plasma in the early stages of the evolution of the Universe. We considered a classical, finite and uniform average magnetic field background $\langle\mathbf{B}(\mathbf{x})\rangle = \mathbf{B}$, subject to white-noise spatial fluctuations with auto-correlation of magnitude $\Delta_B$. By means of the Schwinger representation of the propagator in the average magnetic field as a reference system, we used the replica formalism to study the effects of the magnetic noise in the form of renormalized quasi-particle parameters, leading to an effective charge and an effective refraction index, that depend not only on the energy scale, as usual, but also on the magnitude of the noise $\Delta_B$ and the average field $\mathbf{B}$.

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Jorge David Castaño-Yepes, Marcelo Loewe, Enrique Muñoz, Juan C. Rojas, Renato Zamora. 2022-11-30. QED Fermions in a noisy magnetic field background. https://doi.org/10.1103/physrevd.107.096014

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