August 30, 10:15 in A315   

Shahin Sheikh-Jabbari (IPM, Tehran)


 

Gauge-flation: Inflation from Non-Abelian Gauge Fields

Abstract: We introduce an inflationary scenario, Non-Abelian Gauge Field Inflation or gauge-flation for short, in which slow-roll inflation is driven by non-Abelian gauge field minimally coupled to gravity. I present a detailed analysis, both numerical and analytical, of the gauge-flation. By studying the phase diagrams of the theory, we show that getting enough number of e-folds during a slow-roll inflation is fairly robust to the choice of initial gauge field values. In addition, I show the results of the gauge-flation cosmic perturbation theory which has its own specific features and novelties. The specific gauge-flation model I analyze in this talk has two parameters, a cutoff scale Lambda and the gauge coupling g. Fitting our results with the current cosmological data fixes Lambda ~ 10 H ~ 10^{15} GeV (H is the Hubble parameter) and g ~ 10^{-4}, which are in the natural range of parameters in generic particle physics beyond standard models. Our model also predicts a tensor-to-scalar ratio r>0.05, in the range detectable by the Planck satellite.