Maximising the scientific return from cosmic non-Gaussianity
Byrnes, Christian (University of Bielefeld)

The model of local non-Gaussianity, parameterised by the constant non-linearity parameter fNL, is an extremely popular description of non-Gaussianity. However, a mild scale-dependence of fNL is natural. This scale dependence is a new observable, potentially detectable with the Planck satellite, which helps to further discriminate between models of inflation. It is sensitive to properties of the early universe which are not probed by the standard observables. In a complementary way, the trispectrum also contains important information about non-Gaussianity which the bispectrum does not capture. Using simple models, I will demonstrate how scale-dependence and the trispectrum provide a powerful probe of the early universe.