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arXiv · 1209.2156

Three-form inflation and non-Gaussianity

David J. Mulryne·Johannes Noller·Nelson J. Nunes
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Abstract

We calculate the perturbed action, at second and third order, for a massive three-form field minimally coupled to gravity, and use it to explore the observational predictions of three-form inflation. One intriguing result is that the value of the spectral index is nearly independent of the three-form potential, being fixed solely by the number of e-folds of inflation, with n_s=0.97 for the canonical number of 60. Considering the bispectrum, we employ standard techniques to give explicit results for two models, one of which produces a large non-Gaussianity. Finally, we confirm our results by employing a duality relating the three-form theory to a non-canonical scalar field theory and explicitly re-computing results in this dual picture.

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David J. Mulryne, Johannes Noller, Nelson J. Nunes. 2012-12-11. Three-form inflation and non-Gaussianity. https://doi.org/10.1088/1475-7516%2F2012%2F12%2F016

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