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arXiv · gr-qc/0310085

Cosmic magnetic fields from velocity perturbations in the early Universe

Gerold Betschart·Peter K. S. Dunsby·Mattias Marklund
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Abstract

We show, using a covariant and gauge-invariant charged multifluid perturbation scheme, that velocity perturbations of the matter-dominated dust Friedmann-Lemaitre-Robertson-Walker (FLRW) model can lead to the generation of cosmic magnetic fields. Moreover, using cosmic microwave background (CMB) constraints, it is argued that these fields can reach strengths of between 10^{-28} and 10^{-29} G at the time the dynamo mechanism sets in, making them plausible seed field candidates.

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Gerold Betschart, Peter K. S. Dunsby, Mattias Marklund. 2003-10-21. Cosmic magnetic fields from velocity perturbations in the early Universe. https://doi.org/10.1088/0264-9381%2F21%2F8%2F014

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