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On Non-Gaussianity in the Curvaton Scenario

N. Bartolo·S. Matarrese·A. Riotto
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Abstract

Since a positive future detection of non-linearity in the cosmic microwave background anisotropy pattern might allow to descriminate among different mechanisms giving rise to cosmological adiabatic perturbations, we study the evolution of the second-order cosmological curvature perturbation on super-horizon scales in the curvaton scenario. We provide the exact expression for the non-Gaussianity in the primordial perturbations including gravitational second-order corrections which are particularly relevant in the case in which the curvaton dominates the energy density before it decays. As a byproduct, we show that in the standard scenario where cosmological curvature perturbations are induced by the inflaton field, the second-order curvature perturbation is conserved even during the reheating stage after inflation.

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N. Bartolo, S. Matarrese, A. Riotto. 2003-11-28. On Non-Gaussianity in the Curvaton Scenario. https://doi.org/10.1103/physrevd.69.043503

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