Accurately determining inflationary perturbations

Andrew R Liddle; Ian J Grivell

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arXiv · astro-ph/9701031

Accurately determining inflationary perturbations

Andrew R Liddle·Ian J Grivell

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Abstract

Cosmic microwave anisotropy satellites promise extremely accurate measures of the amplitude of perturbations in the universe. We use a numerical code to test the accuracy of existing approximate expressions for the amplitude of perturbations produced by single-field inflation models. We find that the second-order Stewart-Lyth calculation gives extremely accurate results, typically better than one percent. We use our code to carry out an expansion about the general power-law inflation solution, providing a fitting function giving results of even higher accuracy.

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Andrew R Liddle, Ian J Grivell. 1997-01-08. Accurately determining inflationary perturbations. https://arxiv.org/abs/astro-ph/9701031

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