Bispectra from two-field inflation using the long-wavelength formalism
Tzavara, Eleftheria (Universite Paris Sud-11)

The future detection of, or improved constraints on, the non-Gaussianity of the CMB sky is one of the most promising observational tests of inflation, capable of narrowing down the immense number of models in the literature. In this talk I will introduce a formalism to compute the non-Gaussianity parameter fNL produced during two-field inflation, using as only assumption the long-wavelength approximation. This formalism allows for a simple physical interpretation of the different parts of fNL in terms of adiabatic and isocurvature modes, providing insight into the behaviour of the different transient and persistent contributions. I will present both exact and approximated slow-roll results and compare with the delta-N formalism where possible.