Simulations are an invaluable tool in astrophysics to test theories relating to processes that take millions and billions of years. Within the last decades, cosmological simulations have drastically improved on their power to compare simulation with observations: from simulations only tracing the gravitational effects of cosmic structure formation (“dark matter only / N-body simulations”) to fully hydro-dynamic simulations that form galaxy populations resembling observed galaxies.
An upcoming new generation of cosmological simulations further advances the opportunities for a more direct comparison to observed galaxies. This is not only achieved by an increased mass and spatial resolution, but also by an innovative physical and chemical model of the gas phases of the interstellar medium (ionized, neutral atomic, molecular). This allows to self-consistently model the multi-phase interstellar medium (ISM) and produce more realistic mock observations. I will present first results of these new simulations and show how a multi-phase ISM can impact some of the small-scale challenges of the current standard cosmological model.
This improved model for baryon physics also allows us to better study the impact on the formation of dwarf galaxies on the assumed dark matter particle. This will be illustrated by performing statistical test on the galaxy populations within cold and warm (sterile neutrino) dark matter simulations.