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arXiv · 1912.12977

Preheating in radiative corrections to $\phi^4$ inflation with non-minimal coupling in Palatini formulation

Nilay Bostan
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Abstract

We discuss the impact of the preheating stage in radiative corrections due to interaction of the inflaton to fermions to $\phi^4$ inflation with non-minimal coupling in Palatini formulation. In Palatini inflation with large non-minimal coupling the field is allow to return to the plateau region during the reheating stage, so the average equation of state per oscillations is closer to $-1$ than to $1/3$. The incursion in the plateau leads, however, to a highly efficient tachyonic instability able to reheat the Universe in less than one e-fold. By taking into account prescription II discussed in the literature, in the wide range of $\kappa-\xi$, we figure out spectral index $n_s$ and tensor-to-scalar ratio $r$ which are compatible with the data given by the Keck Array/BICEP2 and Planck collaborations.

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Nilay Bostan. 2019-12-30. Preheating in radiative corrections to $\phi^4$ inflation with non-minimal coupling in Palatini formulation. https://arxiv.org/abs/1912.12977

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