Non-linear isocurvature perturbations and non-Gaussianities
- APC (CNRS-Universite Paris 7), 10 rue Alice Domon et Leonie Duquet, 75205 Paris Cedex 13 (France)
- Abdus Salam ICTP, Strada Costiera 11, 34014 Trieste (Italy)
- Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth PO1 2EG (United Kingdom)
We study non-linear primordial adiabatic and isocurvature perturbations and their non-Gaussianity. After giving a general formulation in the context of an extended {delta}N 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 primordial density perturbation. The second example is that of double inflation involving two decoupled massive scalar fields during inflation. In the mixed curvaton-inflaton scenario we find that the bispectrum of primordial isocurvature perturbations may be large and comparable to the bispectrum of adiabatic curvature perturbations.
- OSTI ID:
- 22156834
- Journal Information:
- Journal of Cosmology and Astroparticle Physics, Vol. 2008, Issue 12; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1475-7516
- Country of Publication:
- United States
- Language:
- English
Similar Records
Primordial non-Gaussianity in models with dark matter isocurvature fluctuations
Correlation of isocurvature perturbation and non-Gaussianity