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arXiv · 1305.5260

Resurrecting power law inflation in the light of Planck results

Sanil Unnikrishnan·Varun Sahni
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Abstract

It is well known that a canonical scalar field with an exponential potential can drive power law inflation (PLI). However, the tensor-to-scalar ratio in such models turns out to be larger than the stringent limit set by recent Planck results. We propose a new model of power law inflation for which the scalar spectra index, the tensor-to-scalar ratio and the non-gaussianity parameter $f_{_{\mathbf{NL}}}^{\mathrm{equil}}$ are in excellent agreement with Planck results. Inflation, in this model, is driven by a non-canonical scalar field with an inverse power law potential. The Lagrangian for our model is structurally similar to that of a canonical scalar field and has a power law form for the kinetic term. A simple extension of our model resolves the graceful exit problem which usually afflicts models of power law inflation.

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Sanil Unnikrishnan, Varun Sahni. 2013-10-31. Resurrecting power law inflation in the light of Planck results. https://doi.org/10.1088/1475-7516%2F2013%2F10%2F063

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