Fredagskollokvium: Non-Gaussianity in the Planck satellite data.
Benjamin Racine, Postdoctoral Fellow , ITA
In the standard model of cosmology, the Universe starts with a period of exponential expansion, before the hot Big-Bang, called cosmic inflation. Quantum fluctuations at this epoch would be the seeds for the anisotropies of the Cosmic Microwave Background (CMB), and all the structures of the observable universe. The simplest model of inflation, introduced in the 1980’s, with a unique slowly rolling scalar field, produced nearly Gaussian perturbations, characterized by statistics of order 2. Many models have been proposed since, and some produce deviations to Gaussianity, that we can study with higher order statistics. The ESA Planck Satellite, launched in 2009, observed the CMB temperature and polarization over the full sky with an unprecedented precision. In February 2015, the Planck collaboration published the best constraints to date on non-Gaussian models. In this talk, we will introduce the physics of inflation and the non-Gaussianities, as well as their effect on the CMB. We will show the latest results, using the recent Planck data.