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arXiv · 1808.10475

A new mechanism to enhance primordial tensor fluctuations in single field inflation

Maria Mylova·Ogan Özsoy·Susha Parameswaran·Gianmassimo Tasinato·Ivonne Zavala
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Abstract

We discuss a new mechanism to enhance the spectrum of primordial tensor fluctuations in single field inflationary scenarios. The enhancement relies on a transitory non-attractor inflationary phase, which amplifies the would-be decaying tensor mode, and gives rise to a growth of tensor fluctuations at superhorizon scales. We show that the enhancement produced during this phase can be neatly treated via a tensor duality between an attractor and non-attractor phase, which we introduce. We illustrate the mechanism and duality in a kinetically driven scenario of inflation, with non-minimal couplings between the scalar and the metric.

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Maria Mylova, Ogan Özsoy, Susha Parameswaran, Gianmassimo Tasinato, Ivonne Zavala. 2019-02-21. A new mechanism to enhance primordial tensor fluctuations in single field inflation. https://doi.org/10.1088/1475-7516%2F2018%2F12%2F024

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