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arXiv · 1412.7241

On the possibility of blue tensor spectrum within single field inflation

Yi-Fu Cai·Jinn-Ouk Gong·Shi Pi·Emmanuel N. Saridakis·Shang-Yu Wu
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Abstract

We present a series of theoretical constraints on the potentially viable inflation models that might yield a blue spectrum for primordial tensor perturbations. By performing a detailed dynamical analysis we show that, while there exists such possibility, the corresponding phase space is strongly bounded. Our result implies that, in order to achieve a blue tilt for inflationary tensor perturbations, one may either construct a non-canonical inflation model delicately, or study the generation of primordial tensor modes beyond the standard scenario of single slow-roll field.

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Yi-Fu Cai, Jinn-Ouk Gong, Shi Pi, Emmanuel N. Saridakis, Shang-Yu Wu. 2015-10-26. On the possibility of blue tensor spectrum within single field inflation. https://doi.org/10.1016/j.nuclphysb.2015.09.025

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