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Crossing w=-1 in Gauss-Bonnet Brane World with Induced Gravity

Rong-Gen Cai·Hong-Sheng Zhang·Anzhong Wang
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Abstract

Recent type Ia supernovas data seemingly favor a dark energy model whose equation of state $w(z)$ crosses -1 very recently, which is a much more amazing problem than the acceleration of the universe. In this paper we show that it is possible to realize such a crossing without introducing any phantom component in a Gauss-Bonnet brane world with induced gravity, where a four dimensional curvature scalar on the brane and a five dimensional Gauss-Bonnet term in the bulk are present. In this realization, the Gauss-Bonnet term and the mass parameter in the bulk play a crucial role.

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Rong-Gen Cai, Hong-Sheng Zhang, Anzhong Wang. 2005-06-06. Crossing w=-1 in Gauss-Bonnet Brane World with Induced Gravity. https://doi.org/10.1088/6102%2F44%2F5%2F948

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