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arXiv · 0709.4391

Modified Gravity: living without Birkhoff I. DGP

De-Chang Dai·Irit Maor·Glenn Starkman
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Abstract

We consider the consequences of the absence of Birkhoff's theorem in theories of modified gravity. As an example, we calculate the gravitational force on a test particle due to a spherical mass shell in the Dvali-Gabadaze-Porrati model (DGP). We show that unlike in General Relativity, the force depends on the mass distribution. In particular, the gravitational force within a spherical mass shell depends on the geometric structure of the bulk, and is likely non-zero.

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De-Chang Dai, Irit Maor, Glenn Starkman. 2007-12-26. Modified Gravity: living without Birkhoff I. DGP. https://doi.org/10.1103/physrevd.77.064016

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