The shape of non-Gaussianities

  title={The shape of non-Gaussianities},
  author={Daniel Babich and Paolo Creminelli and Matias Zaldarriaga},
  journal={Journal of Cosmology and Astroparticle Physics},
We study the dependence on the configuration in momentum space of the primordial three-point function of density perturbations in several different scenarios: standard slow-roll inflation, curvaton and variable decay models, ghost inflation, models with higher derivative operators and the DBI model of inflation. We define a cosine between the distributions using a measure based on the ability of experiments to distinguish between them. We find that models fall into two broad categories with… 

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