Primordial Nongaussianity and Large-Scale Structure – Dragan Huterer
Date: Fri. October 17th, 2008, 11:30 am-12:30 pmLocation: Rockefeller 221
The near-absence of primordial nongaussianity is one of the basic predictions of slow roll, single-field inflation, making measurements of nongaussianity fundamental tests of the physics of the early universe. I first review parametrizations of nongaussianity and briefly review the history of its measurements from the CMB and large-scale structure. I then present results from recent work where effects of primordial nongaussianity on the distribution of largest virialized objects was studied numerically and analytically. We found that the bias of dark matter halos takes strong scale dependence in nongaussian cosmological models. Therefore, measurements of scale dependence of the bias, using various tracers of large-scale structure, can – and do – constrain primordial nongaussianity an order of magnitude better than previously thought.