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arXiv · 1807.11938

Eternal Inflation and Swampland Conjectures

Hiroki Matsui·Fuminobu Takahashi
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Abstract

We study if eternal inflation is realized while satisfying the recently proposed string Swampland criteria concerning the range of scalar field excursion, $|\Delta \phi| < \mathcal{D} \cdot M_{\rm P}$, and the potential gradient, $|\nabla V| > c \cdot V/M_{\rm P}$, where $\mathcal{D}$ and $c$ are constants of order unity, and $M_{\rm P}$ is the reduced Planck mass. We find that only the eternal inflation of chaotic type is possible for $c \sim {\cal O}(0.01)$ and $1/\mathcal{D} \sim {\cal O}(0.01)$, and that the Hubble parameter during the eternal inflation is parametrically close to the Planck scale, and is in the range of $2 \pi c \lesssim H_{\rm inf}/M_{\rm P} < 1/\sqrt{3}$.

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BibTeXRIS

Hiroki Matsui, Fuminobu Takahashi. 2018-07-31. Eternal Inflation and Swampland Conjectures. https://doi.org/10.1103/physrevd.99.023533

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