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Modulational instabilities in neutrino--anti-neutrino interactions

Mattias Marklund·Padma K. Shukla·Gerold Betschart·Lennart Stenflo·Dan Anderson·Mietek Lisak
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Abstract

We analyze the collective behavior of neutrinos and antineutrinos in a dense background. Using the Wigner transform technique, it is shown that the interaction can be modelled by a coupled system of nonlinear Vlasov-like equations. From these equations, we derive a dispersion relation for neutrino-antineutrino interactions on a general background. The dispersion relation admits a novel modulational instability. The results are examined, together with a numerical example, and we discuss the induced density inhomogeneities using parameters relevant to the early Universe.

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Mattias Marklund, Padma K. Shukla, Gerold Betschart, Lennart Stenflo, Dan Anderson, Mietek Lisak. 2003-10-22. Modulational instabilities in neutrino--anti-neutrino interactions. https://doi.org/10.1134/1.1787073

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