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arXiv · hep-th/0701241

Primordial perturbations from slow-roll inflation on a brane

Kazuya Koyama·Andrew Mennim·V. A. Rubakov·David Wands·Takashi Hiramatsu
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Abstract

In this paper we quantise scalar perturbations in a Randall-Sundrum-type model of inflation where the inflaton field is confined to a single brane embedded in five-dimensional anti-de Sitter space-time. In the high energy regime, small-scale inflaton fluctuations are strongly coupled to metric perturbations in the bulk and gravitational back-reaction has a dramatic effect on the behaviour of inflaton perturbations on sub-horizon scales. This is in contrast to the standard four-dimensional result where gravitational back-reaction can be neglected on small scales. Nevertheless, this does not give rise to significant particle production, and the correction to the power spectrum of the curvature perturbations on super-horizon scales is shown to be suppressed by a slow-roll parameter. We calculate the complete first order slow-roll corrections to the spectrum of primordial curvature perturbations.

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Kazuya Koyama, Andrew Mennim, V. A. Rubakov, David Wands, Takashi Hiramatsu. 2007-01-26. Primordial perturbations from slow-roll inflation on a brane. https://doi.org/10.1088/1475-7516%2F2007%2F04%2F001

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