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arXiv · 0801.0467

Large Non-Gaussianity Implication for Curvaton Scenario

Qing-Guo Huang
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Abstract

We argue that the typical energy density of a light scalar field should not be less than $H^4$ in the inflationary Universe. This requirement implies that the non-Gaussianity parameter $f_{NL}$ is typically bounded by the tensor-scalar ratio $r$ from above, namely $f_{NL}\lesssim 518\cdot r^{1\over 4}$. If $f_{NL}=10^2$, inflation occurred around the GUT scale.

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Qing-Guo Huang. 2008-10-03. Large Non-Gaussianity Implication for Curvaton Scenario. https://doi.org/10.1016/j.physletb.2008.10.013

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