Mass neutrino oscillations in Robertson--Walker space--time

Along the geodesic we calculate the interference phase of the mass neutrinos propagating in the radial direction in Robertson--Walker space--time. Since our universe is expanding, the phase factor \varPhi is increasing under the condition of the same proper physical distance l. Different values of curvature parameter k in Robertson--Walker metric represent different cosmological models, correspondingly, we obtain the different interference phases.