Dark matter halo as the dispersional gravitational lens

Based on the time- variability of the dark matter (DM) parameter of state (PoS) type of omega(t) = omega(0) + omega(alpha) center dot (t/T)(alpha) , T) a, the conception of dispersional gravitational lens (DGL) was proposed. The dependency of refractive index of DM halo on its own global oscillations was found. It was shown that DM does not oscillate with optical or ultraviolet and Xray diapasons, but it may oscillate with essentially low frequency omega(DM) >= 10(-15) Hz. Hence, it is possible to talk about the ultra weak DM oscillations, and the very cold dark matter (VCDM) particles whose masses are larger than m(VCDM) >= 10(-42) eV. It was marked briefly that DM global oscillations will gradually pump with elastic energy the galaxy's baryonic matter. Hence, they may be the real reason of its subsequent fragmentation and the inner galaxy structure formation.