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arXiv · 1501.07089

Slow-roll inflationary senario in the maximally extended background

A. A. Asgari·A. H. Abbassi
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Abstract

During the inflationary epoch,geometry of the universe may be described by quasi-de Sitter space. On the other hand,maximally extended de Sitter metric in the comoving coordinates accords with a special FLRW model with positive spatial curvature,so in this article we focus on the positively curved inflationary paradigm.For this purpose,first we derive the power spectra of comoving curvature perturbation and primordial gravitational waves in a positively curved FLRW universe according to the slowly rolling inflationary senario. It can be shown that the curvature spectral index in this model automatically has a small negative running parameter which is compatible with observational measurements.Then,by taking into account the curvature factor,we investigate the relative amplitude of the scalar and tensor perturbations.It would be clarified that the tensor-scalar ratio for this model against the spatially flat one,depends on the waelength of the perturbative models directly.

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A. A. Asgari, A. H. Abbassi. 2015-01-28. Slow-roll inflationary senario in the maximally extended background. https://doi.org/10.1140/epjc%2Fs10052-015-3792-z

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