Gravitational Signals from Noise in the Hubble Diagram – Edward Macaulay
Date: Tue. May 5th, 2015, 11:30 am-12:30 pmLocation: Rockefeller 221
Understanding the nature of the dark universe requires precise measurements of the background expansion history, and also the growth rate of density fluctuations. In this talk, I’ll consider both regimes with supernova lensing for the OzDES spectroscopic survey – which is measuring the redshifts of hundreds of supernova and thousands of galaxies identified by the Dark Energy Survey. I’ll start by reviewing the more established method of growth rate measurements with Redshift Space Distortions, and discuss possible tension between RSDs and expectations from Planck CMB measurements. I’ll then consider how OzDES can place novel constraints on the growth rate and amplitude of density fluctuations by correlating noise in the supernova Hubble diagram with the gravitational effects of lensing and peculiar velocities expected from the observed density field.