Tuesday 01 September 2015
to 15:00 at
Martin Winkler (Bethe Center for Theoretical Physics, Bonn University)
Cosmic inflation, driven by the potential energy of a scalar field, provides a very successful description of the early universe. Axions with their shift symmetries give rise to flat directions in the potential which makes them perfect candidates for the inflaton. The simplest realization, known as “natural inflation“, however, requires a trans-Planckian axion scale. It is not obvious, whether the global shift symmetry survives quantum gravity effects. As a way out, the axion alignment mechanism has been proposed to generate a large effective axion scale from two sub-Planckian axions. I will discuss realizations of aligned natural inflation and the challenges they are facing. I will also comment on the observational status.
(Host: Stefan Vogl)