Inflationary predictions at small gamma

Ewa Czuchry

doi:10.1016/j.physletb.2009.05.065

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arXiv · 0812.1409

Inflationary predictions at small gamma

Ewa Czuchry

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Abstract

This paper explores single field inflation models with a constant, but arbitrary speed of sound c_s, obtained by deforming the kinetic energy terms to a Dirac-Born-Infeld form. Allowing c_s<1 provides a simple parameterization of non-gaussianity. The dependence of inflationary observables on the parameter c_s is considered in the leading order slow roll approximation. The results show that in most cases the dependence is actually rather weak for the range of c_s allowed by existing bounds on non-gaussianity.

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BibTeX RIS

Ewa Czuchry. 2008-12-08. Inflationary predictions at small gamma. https://doi.org/10.1016/j.physletb.2009.05.065

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