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arXiv · 0712.3806

Holographic Dark Energy in Braneworld Models with a Gauss-Bonnet Term in the Bulk. Interacting Behavior and the w =-1 Crossing

E. N. Saridakis
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Abstract

We apply bulk holographic dark energy in general braneworld models with a Gauss-Bonnet term in the bulk and an induced gravity term and a perfect fluid on the brane. Without making any additional assumptions we extract the Friedmann equation on the physical brane and we show that a $ρ$-$ρ_Λ$ coupling arises naturally by the full 5D dynamics. The low-energy (late-time) evolution reveals that the effective 4D holographic dark energy behaves as ``quintom'', that is it crosses the phantom divide $w=-1$ during the evolution. In particular, the Gauss-Bonnet contribution decreases the present value of $w_Λ$, while it increases the growing rate of $w_Λ(z)$ with $z$, in comparison with the case where such a term is absent.

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E. N. Saridakis. 2008-02-19. Holographic Dark Energy in Braneworld Models with a Gauss-Bonnet Term in the Bulk. Interacting Behavior and the w =-1 Crossing. https://doi.org/10.1016/j.physletb.2008.02.032

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