Speaker: Sabino Matarrese (Padova U.)
Title: Cosmology going non-linear
Abstract:
The standard approach to cosmological observables is based upon a homogeneous and isotropic background model on top of which small linear perturbations are considered. While the need to go beyond such a first-order approach is universally recognized when dealing with cosmic structure formation, there are several other consequences of "going non-linear" which have become an important tool in cosmological analyses during the last 20-30 years and others which are still poorly explored. In this talk, I will review several examples of deviations from linearity, such as: production of primordial non-Gaussian signals, production of gravitational waves and magnetic fields out of scalar density fluctuations, production of density perturbations out of gravitational waves, as well as non-vanishing cross-correlations among seemingly independent observables.