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arXiv · 1307.7864

Curvaton with nonminimal derivative coupling to gravity

Kaixi Feng·Taotao Qiu·Yun-Song Piao
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Abstract

We show a curvaton model, in which the curvaton has a nonminimal derivative coupling to gravity. Thanks to such a coupling, we find that the scale-invariance of the perturbations can be achieved for arbitrary values of the equation-of-state of background, provided that it is nearly a constant. We also discussed about tensor perturbations, the local non-Gaussianities generated by the nonminimal derivative coupling curvaton model, as well as the adiabatic perturbations which are transferred from the field perturbations during the curvaton decay.

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Kaixi Feng, Taotao Qiu, Yun-Song Piao. 2014-01-18. Curvaton with nonminimal derivative coupling to gravity. https://doi.org/10.1016/j.physletb.2014.01.008

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