Non-Gaussianities in New Ekpyrotic Cosmology.

@article{Buchbinder2008NonGaussianitiesIN,
  title={Non-Gaussianities in New Ekpyrotic Cosmology.},
  author={E. Buchbinder and J. Khoury and B. Ovrut},
  journal={Physical review letters},
  year={2008},
  volume={100 17},
  pages={
          171302
        }
}
The new ekpyrotic model is an alternative scenario of the early Universe which relies on a phase of slow contraction before the big bang. We calculate the 3-point and 4-point correlation functions of primordial density perturbations and find a generically large non-Gaussian signal, just below the current sensitivity level of cosmic microwave background experiments. This is in contrast with slow-roll inflation, which predicts negligible non-Gaussianity. The model is also distinguishable from… Expand

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