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arXiv · 1512.08490

Gravitational waves in $\alpha-$attractors

K. Sravan Kumar·João Marto·Paulo Vargas Moniz·Suratna Das
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Abstract

We study inflation in the $\alpha-$attractor model under a non-slow-roll dynamics with an ansatz proposed by Gong \& Sasaki \cite{Gong:2015ypa} of assuming $N=N\left(\phi\right)$. Under this approach, we construct a class of local shapes of inflaton potential that are different from the T-models. We find this type of inflationary scenario predicts an attractor at $n_{s}\sim0.967$ and $r\sim0.00055$. In our approach, the non-slow-roll inflaton dynamics are related to the $\alpha-$parameter which is the curvature of K\"ahler geometry in the SUGRA embedding of this model.

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K. Sravan Kumar, João Marto, Paulo Vargas Moniz, Suratna Das. 2015-12-28. Gravitational waves in $\alpha-$attractors. https://doi.org/10.1142/9789813226609_0571

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