Astro Seminar: "The Local Universe as a Cosmological Lens "

Wed, 09/23/2015 - 14:00 - 16:00
Jonathan Hargis (Haverford)

The local universe serves as a lens through which we can understand the formation of galaxies in a dark energy + cold dark matter(LCDM) context.  Numerical simulations suggest that galaxies grow hierarchically; that is, from the continuous build-up and tidal destruction of dwarf galaxies and globular clusters.  The discovery of numerous satellite dwarf galaxies and tidal stellar streams in the halo of the Milky Way and Andromeda generally support this picture.  However, detailed observations reveal tensions with LCDM and uncertainties in galaxy formation theory on small scales.  In this talk, I will discuss how current and futureresearch projects are aiming to address these issues using (1) LCDM galaxy formation simulations and (2) observations of the resolved stellar populations of nearby galaxies (d < 4 Mpc). Lastly, I will discuss howfuture surveys and facilties such as LSST and GMT/TMT will improve both our understanding LCDM cosmology on small scales and the formation of the faintest galaxies.