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arXiv · hep-th/0509136

Cosmic Acceleration Driven by Mirage Inhomogeneities

Christophe Galfard·Cristiano Germani·Alex Kehagias
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Abstract

A cosmological model based on an inhomogeneous D3-brane moving in an AdS_5 X S_5 bulk is introduced. Although there is no special points in the bulk, the brane Universe has a center and is isotropic around it. The model has an accelerating expansion and its effective cosmological constant is inversely proportional to the distance from the center, giving a possible geometrical origin for the smallness of a present-day cosmological constant. Besides, if our model is considered as an alternative of early time acceleration, it is shown that the early stage accelerating phase ends in a dust dominated FRW homogeneous Universe. Mirage-driven acceleration thus provides a dark matter component for the brane Universe final state. We finally show that the model fulfills the current constraints on inhomogeneities.

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Christophe Galfard, Cristiano Germani, Alex Kehagias. 2006-02-02. Cosmic Acceleration Driven by Mirage Inhomogeneities. https://doi.org/10.1088/0264-9381%2F23%2F6%2F010

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