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arXiv · 1403.5163

Blue running of the primordial tensor spectrum

Jinn-Ouk Gong
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Abstract

We examine the possibility of positive spectral index of the power spectrum of the primordial tensor perturbation produced during inflation in the light of the detection of the B-mode polarization by the BICEP2 collaboration. We find a blue tilt is in general possible when the slow-roll parameter decays rapidly. We present two known examples in which a positive spectral index for the tensor power spectrum can be obtained. We also briefly discuss other consistency tests for further studies on inflationary dynamics.

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Jinn-Ouk Gong. 2014-07-09. Blue running of the primordial tensor spectrum. https://doi.org/10.1088/1475-7516%2F2014%2F07%2F022

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