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Curvaton Potential Terms, Scale-Dependent Perturbation Spectra and Chaotic Initial Conditions

John McDonald
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Abstract

The curvaton scenario predicts an almost scale-invariant spectrum of perturbations in most inflation models. We consider the possibility that renormalisable phi^4 or Planck scale-suppressed non-renormalisable curvaton potential terms may result in an observable deviation from scale-invariance. We show that if the curvaton initially has a large amplitude and if the total number of e-foldings of inflation is less than about 300 then a running blue perturbation spectrum with an observable deviation from scale-invariance is likely. D-term inflation is considered as an example with a potentially low total number of e-foldings of inflation. A secondary role for the curvaton, in which it drives a period of chaotic inflation leading to D-term or other flat potential inflation from an initially chaotic state, is suggested.

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John McDonald. 2003-12-08. Curvaton Potential Terms, Scale-Dependent Perturbation Spectra and Chaotic Initial Conditions. https://doi.org/10.1088/1475-7516%2F2003%2F12%2F005

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