A universe with a constant expansion rate

Abstract

One of the strongest supports for the existence of a cosmological vacuum energy density Λ is given by the SN-Ia luminosities as function of the redshift z of the host galaxies, since they seem to indicate an accelerated expansion of the universe in more recent cosmic times. In this paper, we show that one in fact, however, can start out from the astronomical observations of two-point correlation functions regulating the positions of galaxies and clusters of galaxies and derive from them the average cosmic mass density in the universe. We obtained that for the scale-invariant mass distribution derived from these correlation functions we only obtain a finite mass density for a positive curvature parameter + while for curvature parameters 0 k = and 1 k = − one obtains vanishing cosmic mass densities. In these latter universes one consequently would find conditions for a “coasting cosmology” fulfilled which abolishes the need for a cosmic vacuum energy . Λ