Chaotic inflation, radiative corrections and precision cosmology

TL;DR

This paper investigates how radiative corrections influence chaotic inflation models, demonstrating their compatibility with recent cosmological data and providing parameter constraints for phi^2 and phi^4 inflation scenarios.

Contribution

It shows that radiative corrections can reconcile chaotic inflation models with observational data, offering new parameter bounds and emphasizing the importance of quantum effects during inflation.

Findings

Radiative corrections significantly affect inflationary predictions.

Chaotic inflation models remain compatible with WMAP data when including corrections.

Derived specific bounds on correction parameters and inflationary observables.

Abstract

We employ chaotic (phi^2 and phi^4) inflation to illustrate the important role radiative corrections can play during the inflationary phase. Yukawa interactions of phi, in particular, lead to corrections of the form -kappa phi^4 ln(phi/mu), where kappa>0 and mu is a renormalization scale. For instance, phi^4 chaotic inflation with radiative corrections looks compatible with the most recent WMAP (5 year) analysis, in sharp contrast to the tree level case. We obtain the 95% confidence limits 2.4x10^-14<~kappa<~5.7x10^-14, 0.931<~n_s<~0.958 and 0.038<~r<~0.205, where n_s and r respectively denote the scalar spectral index and scalar to tensor ratio. The limits for phi^2 inflation are kappa<~7.7x10^-15, 0.929<~n_s<~0.966 and 0.023<~r<~0.135. The next round of precision experiments should provide a more stringent test of realistic chaotic phi^2 and phi^4 inflation.