Lifting cosmic degeneracy within a single quasar survey

Abstract

In the almost Friedmann-Lema^itre model of the Universe, the density parameter, Omega_matter, and the cosmological constant, Omega_Lambda, measure curvature. Several linearly degenerate relations between these two parameters have recently been measured. Here, large scale structure correlations at \~100-150 h^-1 Mpc are found in the comoving three-dimensional separations of redshift z \approx 2 quasars. These function as a comoving standard rod of length L_LSS \approx 130+-10 h^-1 Mpc. A local maximum in the correlation function at \approx L_LSS/2 also appears to be significant. By combining separate radial and tangential standard ruler analyses, the lifting of the Omega_matter - Omega_Lambda linear degeneracy within a single data set is demonstrated for the first time.