Scale dependence of local f{sub NL}
- Fakultät für Physik, Universität Bielefeld, Postfach 100131, 33501 Bielefeld (Germany)
- Institut für Theoretische Physik, Universität Heidelberg, Philosophenweg 16 and 19, 69120 Heidelberg (Germany)
- Institute of Cosmology and Gravitation, University of Portsmouth, Dennis Sciama Building, Portsmouth, PO1 3FX (United Kingdom)
We consider possible scale-dependence of the non-linearity parameter f{sub NL} in local and quasi-local models of non-Gaussian primordial density perturbations. In the simplest model where the primordial perturbations are a quadratic local function of a single Gaussian field then f{sub NL} is scale-independent by construction. However scale-dependence can arise due to either a local function of more than one Gaussian field, or due to non-linear evolution of modes after horizon-exit during inflation. We show that the scale dependence of f{sub NL} is typically first order in slow-roll. For some models this may be observable with experiments such as Planck provided that f{sub NL} is close to the current observational bounds.
- OSTI ID:
- 22272999
- Journal Information:
- Journal of Cosmology and Astroparticle Physics, Vol. 2010, Issue 02; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1475-7516
- Country of Publication:
- United States
- Language:
- English
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