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arXiv · 1403.4729

Discovery of Large Scale Tensor Mode and Chaotic Inflation in Supergravity

Keisuke Harigaya·Tsutomu T. Yanagida
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Abstract

The BICEP2 collaboration has recently reported a large tensor fluctuation in the cosmic microwave background, which suggests chaotic inflation models. In this letter, we reconsider the chaotic inflation model in the supergravity. We introduce a non-holomorphic shift-symmetry breaking parameter, which we expect to exist in general, and discuss its effect on the inflaton dynamics. We show that the model predicts a sizable deviation from the original chaotic inflation model and the predicted tensor fluctuation can lie between the BICEP2 result and the upper bound given by the Planck experiment with a small shift-symmetry breaking parameter. The model is characterized by only two parameters, which yields predictability and testability in future experiments.

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Keisuke Harigaya, Tsutomu T. Yanagida. 2014-05-21. Discovery of Large Scale Tensor Mode and Chaotic Inflation in Supergravity. https://doi.org/10.1016/j.physletb.2014.05.012

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