Non-linear isocurvature perturbations and non-Gaussianities

作者：Langlois David^*; Vernizzi Filippo; Wands David

来源：Journal of Cosmology and Astroparticle Physics, 2008, (12): 004.

DOI：10.1088/1475-7516/2008/12/004

• cosmological perturbation theory
• inflation
• physics of the early universe

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.

• 出版日期2008-12