Evolution of environmental dependence of galaxy properties over cosmic time: comparison between observations and simulations

Understanding the environmental dependence of galaxy properties and its evolution over cosmic time is one of key issues in the study of galaxy formation and evolution. Among many tight correlations between galaxy properties and environment, the star formation activity of galaxies and its evolution has not well reproduced in cosmological simulations. Here we discuss recent progress of comparisons between observations and simulations focusing on the reproduction of the observed reversal of star formation rate (SFR) – density relation in cosmological hydrodynamical simulations. We emphasize the importance of hydrodynamical simulations of large cosmological volumes for direct comparisons with observations.