Vendredi 18 mars 2016 à 14h15
Auditoire Stueckelberg, Ecole de Physique

The polarized microwave background: from neutrinos to gravitational waves

Joanna Dunkley, University of Oxford

Measurements of the relic Cosmic Microwave Background radiation have taught us a great deal about the origins and content of the universe, but there is still more information to be extracted. The fine-scale features in the polarization of this light tell us about the number and mass of the lightest sub-eV particles in the universe. Larger-scale features could reveal a signature of gravitational waves generated during a very energetic inflationary expansion in the early universe. I will talk in particular about the Atacama Cosmology Telescope in northern Chile, an experiment that is measuring the polarization of the CMB light. I will show early results from the experiment and discuss preparations for a large upcoming survey which will cover half the sky and overlaps large optical cosmological surveys.