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arXiv · 1411.3845

Brane induced cosmological acceleration and crossing of w_{eff}=-1

Nobuyuki Motoyui
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Abstract

The cosmological observation indicates that the effective equation of state parameter $w_{eff}$ varies with $z$: It changes from $w_{eff}>-1$ to $w_{eff}<-1$ at $z\sim 0.2$. We investigate under which condition it exhibits such behaviors based on the five-dimensional braneworld scenario. It is possible in the model with or without an energy exchange between the four dimensional universe and the fifth dimension. However the curves of $w_{eff}$ are quite different between the two cases.

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Nobuyuki Motoyui. 2014-11-14. Brane induced cosmological acceleration and crossing of w_{eff}=-1. https://doi.org/10.1142/s0217751x14501917

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