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arXiv · 1612.04124

Hamilton-Jacobi approach for quasi-exponential inflation: predictions and constraints after Planck 2015 results

Nelson Videla
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Abstract

In the present work we study the consequences of considering an inflationary universe model in which the Hubble rate has a quasi-exponential dependence in the inflaton field, given by $H(ϕ)=H_{inf}\exp \left[\frac{\fracϕ{m_p}}{p\left(1+\fracϕ{m_p}\right)}\right]$. We analyze the inflation dynamics under the Hamilton-Jacobi approach, which allows us to consider $H(ϕ)$, rather than $V(ϕ)$, as the fundamental quantity to be specified. By comparing the theoretical predictions of the model together with the allowed contour plots in the $n_s-r$ plane and the amplitude of primordial scalar perturbations from the latest Planck data, the parameters charactering this model are constrained. The model predicts values for the tensor-to-scalar ratio $r$ and for the running of the scalar spectral index $dn_s/ d\ln k$ consistent with the current bounds imposed by Planck, and we conclude that the model is viable.

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Nelson Videla. 2017-02-21. Hamilton-Jacobi approach for quasi-exponential inflation: predictions and constraints after Planck 2015 results. https://doi.org/10.1140/epjc%2Fs10052-017-4711-2

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