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arXiv · 1906.10363

Accelerating Universe with a stable extra dimension in cuscuton gravity

Asuka Ito·Yuki Sakakihara·Jiro Soda
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Abstract

We study Kaluza-Klein cosmology in cuscuton gravity and find an exact solution describing an accelerating 4-dimensional universe with a stable extra dimension. A cuscuton which is a non-dynamical scalar field is responsible for the accelerating expansion and a vector field makes the extra dimensional space stable. Remarkably, the accelerating universe in our model is not exactly de Sitter.

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Asuka Ito, Yuki Sakakihara, Jiro Soda. 2019-06-25. Accelerating Universe with a stable extra dimension in cuscuton gravity. https://doi.org/10.1103/physrevd.100.063531

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