Le 19 décembre 2014
De 10h30 à 12h00
Benjamin L’HUILLIER
Korea Institute for Advanced Study, Seoul
Cosmological simulations have become a powerful tool to describe the non-linear regime of structure formation. After reviewing the main aspects of cosmological simulations, I will focus on the effects of the initial conditions on some statistics obtained from cosmological $N$-body simulations, namely the density power spectrum, the halo mass function, and the size distribution of the large-scale structures (LSS), showing that second order Lagrangian perturbation theory (2LPT) is needed to obtain 1 percent precision, and that the starting redshift must be chosen with care. I will then move on to galaxy evolution in a hierachical Universe. I will focus on computing statistics of halo interactions using the Horizon Run 4 cosmological N-body simulations, and studying the effect of the environment on the interaction rates and its time evolution.