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Sterile Neutrino and Accelerating Universe

P. Q. Hung
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Abstract

If all three neutrino oscillation data were to be confirmed in the near future, it is probable that one might need a sterile neutrino, in addition to the three active ones. This sterile neutrino, nu_S, would be very light with mass m_{nu_S} less than or equal to 1 eV or even with m_{ν_S} approximately 10^{-3} eV according to some scenarios. Why would it be so light? On another front, recent cosmological observations and analyses appear to indicate that the present universe is flat and accelerating, and that the present energy density is dominated by a ``dark variety'', with rho_V approximately (10^{-3}eV)^4. Is it a constant? Is there a link between these apparently unrelated phenomena?

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P. Q. Hung. 2000-10-12. Sterile Neutrino and Accelerating Universe. https://arxiv.org/abs/hep-ph/0010126

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