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arXiv · 1412.3732

Effects of the speed of sound at large-N

Ivonne Zavala
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Abstract

The implications of a smaller than unity speed of sound of the scalar perturbations during cosmic inflation is studied in terms of a model independent large-$N$ approach. We show that the $(n_s, r)$ plane is non-trivially degenerated when the effects of a different than one speed of sound $c_s$ are taken into account. We also discuss the degeneracies due to $c_s$ in the running of the spectral index, $α_s$. We use the bounds on $c_s$ to constrain such degeneracies.

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Ivonne Zavala. 2015-03-05. Effects of the speed of sound at large-N. https://doi.org/10.1103/physrevd.91.063005

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