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arXiv · 0711.2072

Cascading DGP

Claudia de Rham·Gia Dvali·Stefan Hofmann·Justin Khoury·Oriol Pujolas·Michele Redi·Andrew J. Tolley
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Abstract

We present a higher codimension generalization of the DGP scenario which, unlike previous attempts, is free of ghost instabilities. The 4D propagator is made regular by embedding our visible 3-brane within a 4-brane, each with their own induced gravity terms, in a flat 6D bulk. The model is ghost-free if the tension on the 3-brane is larger than a certain critical value, while the induced metric remains flat. The gravitational force law `cascades' from a 6D behavior at the largest distances followed by a 5D and finally a 4D regime at the shortest scales.

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Claudia de Rham, Gia Dvali, Stefan Hofmann, Justin Khoury, Oriol Pujolas, Michele Redi, Andrew J. Tolley. 2007-12-14. Cascading DGP. https://doi.org/10.1103/physrevlett.100.251603

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