Semi-analytical models of galaxy formation and comparison with observations

In this Thesis we attempted to answer to some of the fundamental questions concerning galaxy evolution. In particular when and how galaxies got their present-day stellar content and how this process depends on their mass. In order to address this key issues, we developed a new semi-analytic model of galaxy formation (GECO, Galaxy Evolution COde), that couples a Monte Carlo representation of the hierarchical clustering of dark matter haloes with analytic recipes for the baryonic physics, such as the cooling of the gas, the star formation, the feedback from SN and AGN. We set the model on observations in the local universe and then we predict and compare results for the high redshift galaxies