Evolution of non-Gaussianity in multi-scalar field models
  We study the evolution of non-Gaussianity in multiple-field inflationary models, focusing on three fundamental questions: (a) How is the sign and peak magnitude of the non-linearity parameter fNL related to generic features in the inflationary potential? (b) How sensitive is fNL to the process by which an adiabatic limit is reached, where the curvature perturbation becomes conserved? (c) For a given model, what is the appropriate tool -- analytic or numerical -- to calculate fNL at the adiabatic limit? We summarise recent results obtained by the authors and further elucidate them by considering an inflection point model. 
Joseph Elliston, David Mulryne, David Seery, Reza Tavakol
astro-ph.CO gr-qc hep-th