Aspects of the Inhomogeneous Universe at Low Redshift

by Ido Ben-Dayan (DESY)

Monday 4 Nov 2013, 16:30 → 17:30 Europe/Berlin

DESY Hamburg

Our Universe is homogeneous and isotropic only in an averaged sense. General Relativity (GR) is a non-linear theory and therefore it is important to properly define averages in GR both for theoretical and phenomenological reasons. I will start by describing the "light-cone averaging prescription", followed by some formal results for the theoretically inclined audience. Then I will discuss the effect of small scale inhomogeneities on the luminosity distance - redshift relation within LCDM, the standard model of cosmology. I will then focus on two results of such analysis: 1) The effect of inhomogeneities on the Hubble parameter H_0 and the observed cosmological constant \Omega_{\Lambda}. 2) Inhomogeneities as a probe of the primordial power spectrum on small scales.

Slides DESYtalk.pdf