Abstract: | Galaxy clustering measurements play an essential role in constraining cosmology. Here I present new clustering results obtained from the Sloan Digital Sky Survey (SDSS; z<0.5) and the Australian WiggleZ survey (z<1).
Combining SDSS and WiggleZ data sets we detect a significant baryonic acoustic feature, a relic from early Universe plasma waves that left ripples in the distribution of matter. This 140 Mpc signature is a cosmic standard ruler with wich we test the geometry of the Universe and constrain parameters of the standard LCDM model.
I also present preliminary results of a test of gravity on large-scales (50-110 Mpc), when using anisotropies in galaxy clustering measurements of the SDSS luminous red galaxy sample, Doppler shift measurements are strongly contaminated by degeneracies between the Hubble expansion and peculiar velocities causing an apparent anisotropy in redshift maps. Because these ``redshift distortions" are sensitive to the galaxies' dynamical environment, they can ultimately be used to test General Relativity and alternative models. |