Formation of Partially Dark-Matter Galaxies

The problem of galactic formation and evolution should be solved on the basis of the Standard Model of particle physics. We believe that we live in the quantum 4-dimensional Minkowski space-time with the force-fields gauge-group structure SU_c(3) \times SU_L(2) \times U(1) \times SU_f(3) built-in from the very beginning, i.e., the "background" of our world. From this "background", we can see the lepton world, of atomic sizes, and also the quark world, of (fermi)^3 sizes. Basing on this belief, we study galactic formation and evolution, concluding that our Cosmos should end up with "model" galaxies. A model galaxy is the one in which a spiral visible ordinary-matter galaxy, such as our Milky Way and satellites, is surrounded by a huge dark-matter neutrino halo. As a byproduct (of studying the Standard Model), we find that neutrinos will be the {\it only long-lived} dark-matter particles.