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arXiv · hep-th/0202060

String inspired braneworld cosmology

Cristiano Germani·Carlos F. Sopuerta
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Abstract

We consider braneworld scenarios including the leading correction to the Einstein-Hilbert action suggested by superstring theory, the Gauss-Bonnet term. We obtain and study the complete set of equations governing the cosmological dynamics. We find they have the same form as those in Randall-Sundrum scenarios but with time-varying four-dimensional gravitational and cosmological constants. Studying the bulk geometry we show that this variation is produced by bulk curvature terms parameterized by the mass of a black hole. Finally, we show there is a coupling between these curvature terms and matter that can be relevant for early universe cosmology.

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Cristiano Germani, Carlos F. Sopuerta. 2002-05-20. String inspired braneworld cosmology. https://doi.org/10.1103/physrevlett.88.231101

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