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Generating the primordial curvature perturbation from inflation

David H. Lyth
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Abstract

The scale--independence of the primordial curvature perturbation suggests that it comes from the vacuum fluctuation during inflation of a light scalar field. This field may be the inflaton, or a different `curvaton' field. The observation of primordial non--gaussianity would be a smoking gun for the curvaton model, while the observation of gravitational waves originating during slow--roll inflation would rule out the model.

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David H. Lyth. 2002-06-01. Generating the primordial curvature perturbation from inflation. https://arxiv.org/abs/hep-ph/0205266

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