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arXiv · 0802.3573

Running spectral index from shooting-star moduli

Tomohiro Matsuda
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Abstract

We construct an inflationary model that is consistent with both large non-Gaussianity and a running spectral index. The scenario of modulated inflation suggests that modulated perturbation can induce the curvature perturbation with a large non-Gaussianity, even if the inflaton perturbation is negligible. Using this idea, we consider a multi-field extension of the modulated inflation scenario and examine the specific situation where different moduli are responsible for the perturbation at different scales. We suppose that the additional moduli (shooting-star moduli) is responsible for the curvature perturbation at the earlier inflationary epoch and it generates the fluctuation with n>1 spectral index at this scale. After a while, another moduli (or inflaton) takes the place and generates the perturbation with n<1. At the transition point the two fluctuations are comparable with each other. We show how the spectral index is affected by the transition induced by the shooting-star moduli.

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Tomohiro Matsuda. 2008-02-25. Running spectral index from shooting-star moduli. https://doi.org/10.1088/1126-6708%2F2008%2F02%2F099

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