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arXiv · 1204.6214

Observational constraints on K-inflation models

Sheng Li·Andrew R. Liddle
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Abstract

We extend the ModeCode software of Mortonson, Peiris and Easther to enable numerical computation of perturbations in K-inflation models, where the scalar field no longer has a canonical kinetic term. Focussing on models where the kinetic and potential terms can be separated into a sum, we compute slow-roll predictions for various models and use these to verify the numerical code. A Markov chain Monte Carlo analysis is then used to impose constraints from WMAP7 data on the addition of a term quadratic in the kinetic energy to the Lagrangian of simple chaotic inflation models. For a quadratic potential, the data do not discriminate against addition of such a term, while for a quartic (λϕ^4) potential inclusion of such a term is actually favoured. Overall, constraints on such a term from present data are found to be extremely weak.

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Sheng Li, Andrew R. Liddle. 2012-07-24. Observational constraints on K-inflation models. https://doi.org/10.1088/1475-7516%2F2012%2F10%2F011

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