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arXiv · 1312.1353

Rescuing Quadratic Inflation

John Ellis·Malcolm Fairbairn·Maria Sueiro
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Abstract

Inflationary models based on a single scalar field $ϕ$ with a quadratic potential $V = \frac{1}{2} m^2 ϕ^2$ are disfavoured by the recent Planck constraints on the scalar index, $n_s$, and the tensor-to-scalar ratio for cosmological density perturbations, $r_T$. In this paper we study how such a quadratic inflationary model can be rescued by postulating additional fields with quadratic potentials, such as might occur in sneutrino models, which might serve as either curvatons or supplementary inflatons. Introducing a second scalar field reduces but does not remove the pressure on quadratic inflation, but we find a sample of three-field models that are highly compatible with the Planck data on $n_s$ and $r_T$. We exhibit a specific three-sneutrino example that is also compatible with the data on neutrino mass difference and mixing angles.

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John Ellis, Malcolm Fairbairn, Maria Sueiro. 2013-12-17. Rescuing Quadratic Inflation. https://doi.org/10.1088/1475-7516%2F2014%2F02%2F044

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