Neutrinos are spin 1/2 fermions that are nearly massless and without electrical charge. Only left-hand neutrinos (negative helicity) with spins anti-parallel to linear momenta are observed. Right-hand anti-neutrinos (positive helicity) exhibit spins parallel to the linear momentum vector. Neutrinos have very small interaction cross-sections and interact weakly with matter. In a geometrical model considered here, neutrinos are conceptualized as vortex rings composed of spinning Planck mass dipoles and propagate along the spin axis.