Quartic inflation and radiative corrections with non-minimal coupling

Abstract

It is well known that the non-minimal coupling $\xi\phi^2R$ between the inflaton and the Ricci scalar affects predictions of single field inflation models. In particular, the $\lambda\phi^4$ quartic inflation potential with $\xi\gtrsim0.005$ is one of the simplest models that agree with the current data. After reviewing the inflationary predictions of this potential, we analyze the effects of the radiative corrections due to couplings of the inflaton to other scalar fields or fermions. Using two different prescriptions discussed in the literature, we calculate the range of these coupling parameter values for which the spectral index $n_s$ and the tensor-to-scalar ratio $r$ are in agreement with the data taken by the Keck Array/BICEP2 and Planck collaborations.