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Super-acceleration on the Brane by Energy Flow from the Bulk

Rong-Gen Cai·Yungui Gong·Bin Wang
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Abstract

We consider a brane cosmological model with energy exchange between brane and bulk. Parameterizing the energy exchange term by the scale factor and Hubble parameter, we are able to exactly solve the modified Friedmann equation on the brane. In this model, the equation of state for the effective dark energy has a transition behavior changing from $w_{de}^{eff}>-1$ to $w_{de}^{eff}<-1$, while the equation of state for the dark energy on the brane has $w>-1$. Fitting data from type Ia supernova, Sloan Digital Sky Survey and Wilkinson Microwave Anisotropy Probe, our universe is predicted now in the state of super-acceleration with $w_{de0}^{eff}=-1.21$.

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Rong-Gen Cai, Yungui Gong, Bin Wang. 2006-02-23. Super-acceleration on the Brane by Energy Flow from the Bulk. https://doi.org/10.1088/1475-7516%2F2006%2F03%2F006

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