Odd gravitational waves from inflation

par Lorenzo Sorbo (University of Massachusetts)

jeudi 19 déc. 2013, 11:00 → 12:00 Europe/Paris

Auditorium (Annecy-le-Vieux)

The existence of a primordial spectrum of gravitational waves is a generic prediction of inflation, and several CMB experiments are going after their signatures. Here I will review the standard mechanism leading to the generation of primordial gravitational waves during inflation. Then 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.