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The spectrum of cosmological perturbations produced by a multi-component inflaton to second order in the slow-roll approximation

Takahiro T. Nakamura·Ewan D. Stewart
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Abstract

We derive general analytic formulae for the power spectrum and spectral index of the curvature perturbation produced during inflation driven by a multi-component inflaton field, up to the second order in the slow-roll approximation. We do not assume any specific properties of the potential or the metric on the scalar field space, except for the slow-roll condition, Einstein gravity, and the absence of any permanent isocurvature modes.

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Takahiro T. Nakamura, Ewan D. Stewart. 1996-04-18. The spectrum of cosmological perturbations produced by a multi-component inflaton to second order in the slow-roll approximation. https://doi.org/10.1016/0370-2693(96)00594-1

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