Covering the Bases
March 18, 2013
Abstract: One of the principal aims of cosmology today is to seek subtle correlations in primordial perturbations, beyond the standard two-point correlation that has been mapped precisely already, that may hint at new physics beyond that in the simplest single-field slow-roll models. I will describe in this talk a new class of such correlations and how they may be sought with galaxy surveys and in the CMB. I will then turn my attention to a new formalism, total-angular-momentum (TAM) waves, that my collaborators and I have recently developed. In most of the literature, cosmological perturbations are decomposed into Fourier modes, or plane waves. However, for calculations that aim to produce predictions for angular correlations on a spherical sky, a decomposition into TAM waves provides a far more direct and intuitive route from theory to observations. I will describe the formalism and illustrate with applications to cosmic shear, three-point correlation functions, and redshift-space distortions.