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Generation of Cosmic Magnetic Fields and Gravitational Waves at Neutrino Decoupling

A. D. Dolgov·D. Grasso
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Abstract

We show that an inhomogeneous cosmological lepton number may have produced turbulence in the primordial plasma when neutrinos entered (almost) free-streaming regime. This effect may be responsible for the origin of cosmic magnetic fields and give rise to a detectable background of gravitational waves. An existence of inhomogeneous lepton asymmetry could be naturally generated by active-sterile neutrino oscillations or by some versions of Affleck and Dine baryogenesis scenario.

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A. D. Dolgov, D. Grasso. 2001-11-08. Generation of Cosmic Magnetic Fields and Gravitational Waves at Neutrino Decoupling. https://doi.org/10.1103/physrevlett.88.011301

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