Connecting the visible Universe to the dark: recent numerical advances on galaxy bias predictions

Abstract: Galaxy bias is the relationship between galaxy formation and the underlying (invisible) large-scale mass distribution, and studying it leads not only to improved cosmological constraints using galaxy data, but invariably also to new insights about the galaxy-environment connection. In this talk I will describe a number of recent breakthroughs made in our ability to make predictions for galaxy bias using hydrodynamical simulations of galaxy formation. By comparing to the bias of dark matter halos, I will discuss what these results can tell us about the environmental dependence of the galaxy-halo connection and the so-called assembly bias signal. I will also discuss how robust priors on galaxy bias from hydrodynamical simulations are imperative to the goal of many future galaxy surveys to constrain inflation models through searches for local-type primordial non-Gaussianity.