Abstract: "We are in the age of large galaxy surveys, such as the Sloan Digital Sky Survey (SDSS), where we can confront theories of galaxy formation with extremely rich observational data sets. Extensive effort has been put forth to understand the manner in which galaxies connect to dark matter halos, as this provides the fundamental link between galaxy formation theory and the concordance LCDM model. I will discuss the recently developed age matching formalism of Hearin & Watson (2013), which is predicated on the assumption that galaxies co-evolve with their dark matter halos. This remarkably simple model accurately predicts new SDSS measurements of galaxy clustering and galaxy-galaxy lensing as a function of stellar mass and color/star formation rate, as well as a variety of satellite galaxy properties. I will also show how age matching is inherently distinct from other successful models, and how emerging statistics of the galaxy distribution, such as "galactic conformity", can distinguish between competing models. The successes of age matching indicate that there exists a simple relation between the cosmic star formation history of galaxies and the dark side of the universe."
Doug Watson, University of Chicago