Neutrino-antineutrino Asymmetry in the Early Universe
نویسنده
چکیده
In this talk I discuss the use of a relic neutrino-antineutrino asymmetry in suppressing active-sterile neutrino oscillations in the early universe. This phenomenon can serve to greatly loosen the well known Big Bang Nucleosynthesis constraints on active-sterile neutrino mixing, and is thus important in some proposed solutions to the solar and atmospheric neutrino anomalies which employ large-angle active-sterile mixing. I first discuss the necessary conditions for the survival of a pre-existing neutrino asymmetry. I then consider the much more interesting phenomenon whereby such an asymmetry can actually be created by active-sterile neutrino oscillations.
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