An absolute cosmological-distance scale and the peculiar-velocity field from proper motions of galaxies

摘要

We suggest a method for extracting important cosmological information from observational data on galaxy proper motions on the celestial sphere. These data can be used to reconstruct the three-dimensional velocities of galaxies relative to the cosmicmicrowave background (peculiar velocities), and to separate the Hubble and peculiar components of the observed redshifts in a large volume for the first time. As a result, it is possible to determine the Hubble constant accurately and independently using the radial velocities of comparatively close galaxies (up to 50 Mpc), and to determine distances to the galaxies and the mass distribution in the neighborhood of the Local group of galaxies. The proposed task may be solved using the future "Millimetron" space radio interferometer.