COSMIC MAGNIFICATION · Cosmic Magnification - A New Window to Cosmology

The unknown nature of dark matter and dark energy represent two of the most puzzling problems in contemporary physics. Observational guidance is essential to constrain the parameter space of possible dark matter candidate particles and to test models of modified gravity. Even more importantly, only cosmological observations seem to be able to shed light on the mystery of dark energy, by directly measuring its energy density as function of redshift. This proposal is aimed at establishing a new cosmological probe - cosmic magnification - that will help to make progress in answering these questions. The magnification effect of weak gravitational lensing (WL) introduces correlations between the positions and magnitudes of high-redshift galaxies and foreground matter. We will measure these correlations from the most powerful WL survey to date and constrain cosmological parameters in a way that is complementary to other probes such as cosmic shear. Important secondary results will include precise clustering and luminosity function measurements of the brightest high-redshift galaxies.