What we do not yet know about star formation in galaxies

Nick Gnedin (Fermilab)

I will discuss the key physical processes that control the atomic-to-molecular gas transition in the interstellar medium, and the effect that transition has on star formation in galaxies. The interplay between radiation field and gas dynamics leads to novel, previously undiscovered feedback processes in galaxy evolution, that are potentially more important than the supernova feedback, and that have not yet been incorporated into cosmological or galactic-scale numerical simulations.