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arXiv · hep-th/0304147

Cosmology of codimension-two braneworlds

James M. Cline·Julie Descheneau·Massimo Giovannini·Jérémie Vinet
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Abstract

We present a comprehensive study of the cosmological solutions of 6D braneworld models with azimuthal symmetry in the extra dimensions, moduli stabilization by flux or a bulk scalar field, and which contain at least one 3-brane that could be identified with our world. We emphasize an unusual property of these models: their expansion rate depends on the 3-brane tension either not at all, or in a nonstandard way, at odds with the naive expected dimensional reduction of these systems to 4D general relativity at low energies. Unlike other braneworld attempts to find a self-tuning solution to the cosmological constant problem, the apparent failure of decoupling in these models is not associated with the presence of unstabilized moduli; rather it is due to automatic cancellation of the brane tension by the curvature induced by the brane. This provides some corroboration for the hope that these models provide a distinctive step toward understanding the smallness of the observed cosmological constant. However, we point out some challenges for obtaining realistic cosmology within this framework.

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James M. Cline, Julie Descheneau, Massimo Giovannini, Jérémie Vinet. 2003-06-30. Cosmology of codimension-two braneworlds. https://doi.org/10.1088/1126-6708%2F2003%2F06%2F048

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