Quantum Smearing in Hybrid Inflation with Chaotic Potentials

TL;DR

This paper investigates how one-loop radiative corrections can modify hybrid inflation models with chaotic potentials, making them compatible with Planck data by adjusting spectral index and tensor-to-scalar ratio.

Contribution

It demonstrates that radiative corrections can reconcile hybrid inflation models with observational constraints, especially reducing tensor-to-scalar ratio and achieving a red-tilted spectral index.

Findings

Radiative corrections improve compatibility with Planck data.

Fermionic corrections reduce tensor-to-scalar ratio.

Models achieve red-tilted spectral index with sub-Planckian fields.

Abstract

We study the impact of one-loop radiative corrections in a non-supersymmetric model of hybrid inflation with chaotic (polynomial-like) potential, $V_0 + \lambda_p \phi^p$. These corrections can arise from the possible couplings of inflaton with other fields which may play active role in the reheating process. The tree-level predictions of these models are shown to lie outside of the Planck's latest bounds on the scalar spectral index $n_s$ and the tensor to scalar ratio $r$. However, the radiatively corrected version of these models, $ V_0 + \lambda_p \phi^p + A \phi^4 \ln \phi$, is fully consistent with the Planck's data. More specifically, fermionic radiative correction ($A<0$) reduces the tensor to scalar ratio significantly and a red-tilted spectral index $n_s<1$, consistent with Planck's data, is obtained even for sub-Planckian field-values.