The Physics of Accretion onto Galaxies

How do galaxies accrete the gas needed to fuel star formation?' remains a fundamental open question in the study of galaxy evolution, without a definitive answer even for low-redshift disks such as the Milky-Way.  I will discuss recent theoretical developments in galaxy accretion physics, and how different modes of accretion can impact galaxy evolution. I will also present novel tests of galaxy accretion models, based on the recent surge in observations of the circumgalactic medium.