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arXiv · 2203.09698

Multi-chaotic inflation with and without spectator field

Yukiyoshi Morishita·Tomo Takahashi·Shuichiro Yokoyama
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Abstract

Motivated by the result of Planck+BICEP/Keck recently released, we investigate the consistency of the multi-field inflation models in terms of the spectral index $n_s$ and the tensor-to-scalar ratio $r$. In this study, we focus on double-inflaton models with and without a spectator field. We find that inflaton with a quadratic potential can become viable when three fields with a specific hierarchical mass spectrum are realized such that two fields act as inflatons and the other one is the spectator. We also discuss the conditions to avoid the fine-tuning, by careful study of how the prediction depends on the background trajectory in the inflaton-field space.

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Yukiyoshi Morishita, Tomo Takahashi, Shuichiro Yokoyama. 2022-03-18. Multi-chaotic inflation with and without spectator field. https://doi.org/10.1088/1475-7516/2022/07/042

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