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Neutrinoless Universe

John F. Beacom·Nicole F. Bell·Scott Dodelson
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Abstract

We consider the consequences for the relic neutrino abundance if extra neutrino interactions are allowed, e.g., the coupling of neutrinos to a light (compared to $m_ν$) boson. For a wide range of couplings not excluded by other considerations, the relic neutrinos would annihilate to bosons at late times, and thus make a negligible contribution to the matter density today. This mechanism evades the neutrino mass limits arising from large scale structure.

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John F. Beacom, Nicole F. Bell, Scott Dodelson. 2004-08-31. Neutrinoless Universe. https://doi.org/10.1103/physrevlett.93.121302

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