On Non-Gaussianity in the Curvaton Scenario
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.
Keywords
Cite
@article{arxiv.hep-ph/0309033,
title = {On Non-Gaussianity in the Curvaton Scenario},
author = {N. Bartolo and S. Matarrese and A. Riotto},
journal= {arXiv preprint arXiv:hep-ph/0309033},
year = {2010}
}
Comments
LaTeX file, 8 pages. Some typos corrected. In Sec. IIIA non-local gradient terms explicitly accounted for in the final non-linear parameter and references added