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arXiv · hep-th/0104023

Cosmological Evolution on Self-Tuned Branes and the Cosmological Constant

Ph. Brax·A. C. Davis
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Abstract

We consider the cosmological evolution of a bulk scalar field and ordinary matter living on the brane world in the light of the constraints imposed by the matter dominated cosmological evolution and a small cosmological constant now. We rule out models with a self-tuned minimum of the four dimensional potential as they would lead to rapid oscillations of the Hubble parameter now. A more natural framework is provided by supergravity in singular spaces where the brane coupling and the bulk potential are related by supersymmetry leading to a four dimensional run-away potential. For late times we obtain an accelerating universe due to the breaking of supersymmetry on the brane with an acceleration parameter of q_0=-4/7 and associated equation of state omega=-5/7.

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Ph. Brax, A. C. Davis. 2001-04-03. Cosmological Evolution on Self-Tuned Branes and the Cosmological Constant. https://doi.org/10.1088/1126-6708%2F2001%2F05%2F007

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