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arXiv · 0807.3336

Modified scalar and tensor spectra in spinor driven inflation

Damien Gredat·S. Shankaranarayanan
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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.

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Damien Gredat, S. Shankaranarayanan. 2008-07-21. Modified scalar and tensor spectra in spinor driven inflation. https://doi.org/10.1088/1475-7516/2010/01/008

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