Event Details

The currently favored cosmological paradigm, Lambda Cold Dark Matter Theory (LCDM), has been widely successful in predicting the counts, clustering, colors, morphologies, and evolution of galaxies on large scales, as well as a variety of cosmological observables. Despite these successes, several challenges have arisen to this model in recent years, most of them occurring at the smallest scales — those of low mass dwarf galaxies (Mstar < 10^7 Msun). To investigate these challenges, I run cosmological (GIZMO/FIRE2) simulations of dwarf galaxies (Mhalo ~10^10 Msun) with 250-30 Msun mass and parsec-sub-pc spatial resolution. This allows us to probe smaller physical scales than previously possible in cosmological simulations, and to make more detailed predictions for the counts, star formation histories, and chemical composition of the lowest mass galaxies ever observed. These highest resolution simulations confirm many results at lower resolution, suggesting they are numerically robust (for a given physical model), but there are also intriguing discrepancies with observations. I will also discuss the implications of my work for the emerging low surface-brightness sky.