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arXiv · 0910.5248

The Origin of Magnetic Fields in Galaxies

Rafael S. de Souza·R. Opher
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Abstract

Microgauss magnetic fields are observed in all galaxies at low and high redshifts. The origin of these intense magnetic fields is a challenging question in astrophysics. We show here that the natural plasma fluctuations in the primordial universe (assumed to be random), predicted by the Fluctuation-Dissipation-Theorem, predicts $\sim 0.034 μG$ fields over $\sim 0.3$ kpc regions in galaxies. If the dipole magnetic fields predicted by the Fluctuation-Dissipation-Theorem are not completely random, microgauss fields over regions $\gtrsim 0.34$ kpc are easily obtained. The model is thus a strong candidate for resolving the problem of the origin of magnetic fields in $\lesssim 10^{9}$ years in high redshift galaxies.

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Rafael S. de Souza, R. Opher. 2010-02-24. The Origin of Magnetic Fields in Galaxies. https://doi.org/10.1103/physrevd.81.067301

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