Reconstruction analysis of galaxy redshift surveys

In the standard model of cosmology, the observed large scale distribution of galaxies arose from gravitational instability of Gaussian primordial mass density fluctuations in the early universe. I test this hypothesis of gravitational structure formation, derive constraints on the value of the cosmological mass density parameter $Wm$, and study the “bias” between luminous galaxies and the dynamically dominant dark matter, by reconstructing the galaxy distribution observed in the IRAS (Infrared Astronomical Satellite) Point Source Catalog Redshift Survey (PSCz).; By combining the complementary desirable features of two previous reconstruction methods, I have developed a hybrid technique for reconstructing a galaxy distribution, given specified assumptions about the value of $Wm$ and bias. I test this method using the outputs of numerical simulations with known initial conditions and find that the hybrid method can best reconstruct the observed galaxy distribution, among all the methods proposed so far to reconstruct a galaxy redshift survey. A reconstruction that incorporates correct assumptions about $Wm$ and bias successfully reproduces the input data, but a reconstruction based on incorrect assumptions fails in a systematic manner. This method can therefore test the gravitational instability model and constrain the value of $Wm$ and the bias.; I present the results of reconstruction analysis of the PSCz catalog using 15 models, each consisting of a set of assumptions regarding the value of $Wm$ and the bias between IRAS galaxies and mass. I find that gravitational instability of Gaussian primordial mass density fluctuations can account for the galaxy distribution in the PSCz catalog, at least for some plausible assumptions about the value of $Wm$ and the biasing between IRAS galaxies and mass. However, unbiased models in which IRAS galaxies trace mass fail to reconstruct the PSCz catalog accurately, both for $Wm$ = 0.4 and for $Wm$ = 1. Low $Wm$ models in which IRAS galaxies are antibiased with respect to the mass distribution are the most successful in reconstructing the PSCz catalog. Further, I find that reconstruction analysis is capable of discriminating between different types of biasing relations, and not just between different amplitude of the bias. In particular, a model with $Wm$ = 0.4 and IRAS galaxies related to the mass distribution according to the predictions of a semi-analytic galaxy formation model is very successful in reproducing the properties of the PSCz galaxy distribution, while another model with very similar values of $Wm$ and the amplitude of bias, but with a different biasing relation, is summarily rejected.