Non-linear isocurvature perturbations and non-Gaussianities
نویسندگان
چکیده
منابع مشابه
Non-linear isocurvature perturbations and non-Gaussianities
We study non-linear primordial adiabatic and isocurvature perturbations and their non-Gaussianity. After giving a general formulation in the context of an extended δN formalism, we analyse in detail two illustrative examples. The first is a mixed curvaton-inflaton scenario in which fluctuations of both the inflaton and a curvaton (a light isocurvature field during inflation) contribute to the p...
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چکیده ندارد.
15 صفحه اولNon-Gaussianity from Isocurvature Perturbations : Analysis of Trispectrum
Non-Gaussianity may exist in the CDM isocurvature perturbation. We provide general expressions for the bispectrum and trispectrum of both adiabatic and isocurvature pertubations. We apply our result to the QCD axion case, and found a consistency relation between the coefficients of the bispectrum and trispectrum : τ (iso) NL ≃ 10 3[f (iso) NL ] 4/3, if the axion is dominantly produced by quantu...
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ژورنال
عنوان ژورنال: Journal of Cosmology and Astroparticle Physics
سال: 2008
ISSN: 1475-7516
DOI: 10.1088/1475-7516/2008/12/004