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arXiv · 1510.05980

Dark Radiation and Inflationary Freedom

Stefano Gariazzo
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Abstract

A relaxed primordial power spectrum (PPS) of scalar perturbations arising from inflation can impact the dark radiation constraints obtained from Cosmic Microwave Background and other cosmological measurements. If inflation produces a non-standard PPS for the initial fluctuations, a fully thermalized light sterile neutrino can be favoured by CMB observations, instead of being strongly disfavoured. In the case of a thermal axion, the constraints on the axion mass are relaxed when the PPS is different from the standard power law.

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Stefano Gariazzo. 2015-10-20. Dark Radiation and Inflationary Freedom. https://doi.org/10.1088/1742-6596%2F718%2F3%2F032006

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