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arXiv · 1312.5944

Does Planck really rule out monomial inflation?

Kari Enqvist·Mindaugas Karciauskas
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Abstract

We consider the modifications of monomial chaotic inflation models due to radiative corrections induced by inflaton couplings to bosons and/or fermions necessary for reheating. To the lowest order, ignoring gravitational corrections and treating the inflaton as a classical background field, they are of the Coleman-Weinberg type and parametrized by the renormalization scale $μ$. In cosmology, there are not enough measurements to fix $μ$ so that we end up with a family of models, each having a slightly different slope of the potential. We demonstrate by explicit calculation that within the family of chaotic $ϕ^2$ models, some may be ruled out by Planck whereas some remain perfectly viable. In contrast, radiative corrections do not seem to help chaotic $ϕ^{4}$ models to meet the Planck constraints.

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Kari Enqvist, Mindaugas Karciauskas. 2013-12-20. Does Planck really rule out monomial inflation?. https://doi.org/10.1088/1475-7516%2F2014%2F02%2F034

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