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arXiv · 1404.1122

Testing Hybrid Natural Inflation with BICEP2

Mariana Carrillo-Gonzalez·Gabriel German·Alfredo Herrera-Aguilar·Juan Carlos Hidalgo·Roberto Sussman
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Abstract

We analyse Hybrid Natural Inflation in view of the recent results for the tensor index reported by BICEP2. We find that it predicts a large running of the scalar spectrum which is potentially detectable by large scale structure and $21\, \mathrm{cm} $ observations. The running of the running is also relatively large becoming close to $10^{-2}$. Along the way, we find general consistency relations at which observables are subject if the slow-roll approximation is imposed. Failure to satisfy these equations by the values obtained for the observables in surveys would be a failure of the slow-roll approximation itself.

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Mariana Carrillo-Gonzalez, Gabriel German, Alfredo Herrera-Aguilar, Juan Carlos Hidalgo, Roberto Sussman. 2014-07-25. Testing Hybrid Natural Inflation with BICEP2. https://doi.org/10.1016/j.physletb.2014.05.062

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