Dark matter in the universe - Massive neutrinos revisited

Abstract

A quantitative model describing the self-consistent distribution of galaxies in clusters and that of visible matter in galaxies is developed, assuming that clouds of neutrinos with mass about 10 eV pervade the universe. The model reproduces the distribution of the galaxies in a cluster; explains the high stellar velocities recently measured in dwarf spheroidals as well as the tidal stability of these systems; fits the profiles of surface density of dwarf spheroidals, ellipticals, and spirals; and gives rise to flat or gently rising rotation curves observed in the optical and 21-cm bands. It is shown that when stars form in an isothermal gas cloud embedded in a much more massive and denser cloud of neutrinos, they acquire a Maxwellian distribution of velocities. These clouds contribute, on average, a density adequate to ensure the closure of the universe.