Modified scalar and tensor spectra in spinor driven inflation
Abstract
One of the firm predictions of the single-scalar field inflationary cosmology is the consistency relation between the scalar and tensor perturbations. It has been argued that such a relation, if observationally verified, would offer strong support for the idea of inflation. In this letter, we critically analyze the validity of the consistency relation in the context of spinflation. Spinflaton -- a scalar condensate of the Elko field -- has a single scalar degree of freedom and leads to the identical acceleration equation as the single canonical scalar field. We obtain the perturbation equations for the Einstein-Elko system and show that (i) The scalar perturbations are purely adiabatic and speed of the perturbations is identically one. (ii) In the slow-roll limit, the scalar and tensor perturbations are nearly scale-invariant and (iii) Obtain the consistency relations for the scalar and tensor spectra.
Cite
@article{arxiv.0807.3336,
title = {Modified scalar and tensor spectra in spinor driven inflation},
author = {Damien Gredat and S. Shankaranarayanan},
journal= {arXiv preprint arXiv:0807.3336},
year = {2010}
}
Comments
11 pages, Revtex4; Titled renamed, References added, Matches with the journal version