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arXiv · 1402.1044

Testing the Origin of Cosmological Magnetic Fields through the Large-Scale Structure Consistency Relations

P. Berger·A. Kehagias·A. Riotto
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Abstract

We study the symmetries of the post-recombination cosmological magnetohydrodynamical equations which describe the evolution of dark matter, baryons and magnetic fields in a self-consistent way. This is done both at the level of fluid equations and of Vlasov-Poisson-Maxwell equations in phase space. We discuss some consistency relations for the soft limit of the (n + 1)-correlator functions involving magnetic fields and matter overdensities. In particular, we stress that any violation of such consistency relations at equal-time would point towards an inflationary origin of the magnetic field.

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P. Berger, A. Kehagias, A. Riotto. 2014-02-05. Testing the Origin of Cosmological Magnetic Fields through the Large-Scale Structure Consistency Relations. https://doi.org/10.1088/1475-7516%2F2014%2F05%2F025

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