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arXiv · 1511.03121

Dilaton assisted two-field inflation from no-scale supergravity

Abstract

We present a two-field inflation model where inflaton field has a non-canonical kinetic term due to the presence of a dilaton field. It is a two-parameter generalization of one-parameter Brans-Dicke gravity in the Einstein frame. We show that in such an inflation model the quartic and quadratic inflaton potentials, which are otherwise ruled out by the present Planck-{\it Keck}/BICEP2 data, yield scalar spectral index and tensor-to-scalar ratio in accordance with the present data. Such a model yield tensor-to-scalar ratio of the order of $10^{-2}$ which is within the reach of $B-$mode experiments like {\it Keck}/BICEP3, CMBPol and thus can be put to test in the near future. This model yields negligible non-Gaussianity and no isocurvature perturbations upto slow-roll approximation. Finally, we show that such a model can be realised in the realm of no-scale supergravity.

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Girish Kumar Chakravarty, Suratna Das, Gaetano Lambiase, Subhendra Mohanty. 2016-07-21. Dilaton assisted two-field inflation from no-scale supergravity. https://doi.org/10.1103/physrevd.94.023521

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