wIt is found that an ensemble of random phase incoherent neutrinos can
generate both the inhomogeneities and magnetic fields in the early un
iverse. Hence, neutrinos can be considered as building blocks of the t
wo most important astrophysical phenomena that are central to modern a
stroparticle physics and cosmology. (C) 1998 American Institute of Phy
sics. [S1070-664X(98)02107-7].