Dark Neutrinos
  Solar, atmospheric and reactor neutrino experiments established that
neutrinos are massive. It is quite natural then to consider neutrinos as
candidate particles for explaining the dark matter in halos around galaxies. We
study the gravitational clustering of these neutrinos within a model of a
massive core and a surrounding spherical neutrino halo. The neutrinos form a
degenerate Fermi gas and a loaded polytropic equation is established. We solve
the equation and we obtain the neutrino density in a galaxy, the size of the
galaxy and the galactic rotational curves. The available data favor a neutrino
with a mass around 10eV. The consequent cosmological implications are examined.
