Gravitational wave constraints on multi-brane inflation

  title={Gravitational wave constraints on multi-brane inflation},
  author={Ian Huston and James E. Lidsey and Steven A. Thomas and John Ward},
  journal={Journal of Cosmology and Astroparticle Physics},
A class of non-canonical inflationary models is identified, where the leading-order contribution to the non-Gaussianity of the curvature perturbation is determined by the sound speed of the fluctuations in the inflaton field. Included in this class of models is the effective action for multiple coincident branes in the finite n limit. The action for this configuration is determined using a powerful iterative technique, based upon the fundamental representation of SU(2). In principle the upper… 

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