Density perturbations arising from multiple field slow-roll inflation
Abstract
In this paper we analyze scalar gravitational perturbations on a Robertson-Walker background in the presence of multiple scalar fields that take values on a (geometrically non-trivial) field manifold during slow-roll inflation. For this purpose modified and generalized slow-roll functions are introduced and their properties examined. These functions make it possible to estimate to what extent the gravitational potential decouples from the scalar field perturbations. The correlation function of the gravitational potential is calculated in an arbitrary state. We argue that using the vacuum state seems a reasonable assumption for those perturbations that can be observed in the CMBR. Various aspects are illustrated by examples with multiple scalar fields that take values on flat and curved manifolds.
Cite
@article{arxiv.hep-ph/0011325,
title = {Density perturbations arising from multiple field slow-roll inflation},
author = {S. Groot Nibbelink and B. J. W. van Tent},
journal= {arXiv preprint arXiv:hep-ph/0011325},
year = {2007}
}
Comments
42 pages; some minor changes and additions