We believe most particles building the Universe and weakly interacting between each other exist in a degenerate (basic) state promoting minimal contribution to the vacuum polarization to estimate which space curvature is used. Because of low temperatures quarks in the form of baryons are distributed in the Universe with a marginal density. That is why the geometrical structure of Metagalaxy does not differ much from the one of flat space. Moreover, it can be assumed that the Minkowski space-time symmetry is induced by physical properties of the Universe fermions in a degenerate state under 0°. It allows to solve not only the problem of the Universe planeness but also the observer horizon (the isotropy problem of the cosmic microwave background from the Universe observer horizon).