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arXiv · 1405.0850

Ghosts in the self-accelerating DGP branch with Gauss-Bonnet effect

Yen-Wei Liu·Keisuke Izumi·Mariam Bouhmadi-Lopez·Pisin Chen
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Abstract

The Dvali-Gabadadze-Porrati brane-world model provides a possible approach to address the late-time cosmic acceleration. However, it has subsequently been pointed out that a ghost instability will arise on the self-accelerating branch. Here, we carefully investigate whether this ghost problem could be possibly cured by introducing the Gauss-Bonnet term in the five-dimensional bulk action, a natural generalization to the Dvali-Gabadadze-Porrati model. Our analysis is carried out for a background where a de Sitter brane is embedded in an anti-de Sitter bulk. Our result shows that the ghost excitations cannot be avoided even in this modified model.

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Yen-Wei Liu, Keisuke Izumi, Mariam Bouhmadi-Lopez, Pisin Chen. 2015-02-09. Ghosts in the self-accelerating DGP branch with Gauss-Bonnet effect. https://doi.org/10.1140/epjc%2Fs10052-015-3463-0

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