The inflationary prediction for primordial non-gaussianity
نویسنده
چکیده
We extend the δN formalism so that it gives all of the stochastic properties of the primordial curvature perturbation ζ if the initial field perturbations are gaussian. The calculation requires only the knowledge of some family of unperturbed universes. A formula is given for the normalisation fNL of the bispectrum of ζ, which is the main signal of non-gaussianity. Examples of the use of the formula are given, and its relation to cosmological perturbation theory is explained.
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تاریخ انتشار 2005