Equilateral non-Gaussianity from multifield dynamics

@article{Tolley2009EquilateralNF,
  title={Equilateral non-Gaussianity from multifield dynamics},
  author={Andrew J. Tolley and Mark Wyman},
  journal={Physical Review D},
  year={2009},
  volume={81},
  pages={043502}
}
The distinctive features of single field inflationary models with nonminimal kinetic terms, like Dirac-Born-Infeld and k inflation, can be captured by more familiar multiple-field inflationary systems of the type that typically arise in low-energy supergravity models. At least one heavy field, which we call the gelaton, has an effective potential which depends on the kinetic energy of the inflaton. Integrating out the gelaton gives rise to an effectively single field system for which the speed… 

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