The Spectrum of Density Perturbations produced during Inflation to Leading Order in a General Slow-Roll Approximation

Abstract

The standard calculation of the spectrum of density perturbations produced during inflation assumes (i) |n-1| << 1 and (ii) |dn/dlnk| << |n-1|. Slow-roll predicts and observations require (i), but neither slow-roll nor observations require (ii). In this paper I derive formulae for the spectrum, spectral index, and running of the spectral index, assuming only (i) and not (ii). I give a large class of observationally viable examples in which these general slow-roll formulae are accurate but the standard slow-roll formulae for the spectral index and running are incorrect.

26 pages, 6 figures

References in corpus (1)

• The Density Perturbation Power Spectrum to Second-Order Corrections in the Slow-Roll Expansion

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