Listening for primordial gravitational waves

Who: Valerie Domcke (Paris Centre for Cosmological Physics)
When: Monday, April 11, 2016 at 14:15
Where: The CP³ meeting room

The recent discovery of gravitational waves by the LIGO collaboration opens up a completely new way of probing the Universe. Gravitational waves are the ultimate probe of the physics of the early universe, carrying information about the cosmic history all the way back to the period of inflation. In this talk I will discuss some possible characteristic signals in the gravitational wave spectrum and how to search for these in the cosmic microwave background as well as in direkt gravitational wave detectors. A particular focus will be on gravitational waves from cosmic inflation. While current CMB bounds predict the generic scale-invariant spectrum to be below the reach of upcoming gravitational wave interferometers, this prospect dramatically changes if the inflaton has a suitable coupling to massless vector fields. In this case, the latter provide a new source of gravitational waves, directly related to the inflaton dynamics. Such a set-up can have striking observational features, such as non-gaussianities in the CMB, production of primordial black holes and a large, highly polarized gravitational wave signal.


Slides from the talk