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Accelerating Universe with a stable extra dimension in cuscuton gravity

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 نشر من قبل Yuki Sakakihara
 تاريخ النشر 2019
  مجال البحث فيزياء
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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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