TH Cosmo Coffee

# Odd gravitational waves from inflation

## by Lorenzo Sorbo (U. Mass.)

Wednesday, 15 January 2014 from to (Europe/Zurich)
at CERN ( 4-2-011 - TH common room )
 Description The existence of a primordial spectrum of gravitational waves is a generic prediction of inflation, and several CMB experiments are going after this signature. Here I will discuss how the coupling of a pseudoscalar inflaton to a gauge field can induce, in a two-step process, gravitational waves with unusual properties such as: (i) a net chirality (ii) a blue spectrum (iii) being detectable in the (relatively) near future by ground-based gravitational interferometers (iv) large nongaussianities even if the scalar perturbations are approximately gaussian.