We study the nature of Dark Energy and Dark Matter, and related aspects of fundamental physics. Our recent projects have primarily used the tools and techniques of observational astronomy, since these provide us the opportunity to measure the properties of the dark sector where the signal is non-zero. Current projects include: Measuring the expansion history of the Universe with Type Ia supernovae, measuring redshifts and masses for the largest clusters of galaxies in the sky (South Pole Telescope cluster survey), devising techniques for precision calibration of astronomical observations, and testing gravity in the solar system with lunar laser ranging (the APOLLO project). Our group is also heavily involved in the development of the Large Synoptic Survey Telescope (LSST), and is also assisting with WFIRST. 

Our sponsors:
National Science Foundation      U.S. Department of Energy