The inflationary paradigm generically predicts Gaussian distributed metric perturbations and a scale-invariant power spectrum. Although current data are in agreement with these predictions, small deviations to Gaussianity might be detectable in high accuracy experiments. Such deviations are a powerful way to discriminate among inflationary models. In particular, I will show that significant non-Gaussian fluctuations could be induced in a large class of multiple field inflationary models. In such models, isocurvature modes develop non trivial fluctuations that are transfered to the metric through a mechanism I will detail. I will then characterize the non-Gaussianities generated in such a framework and study some consequences on the CMB temperature anisotropies.

SPhT, CEA/Saclay