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arXiv · 1301.4327

Cosmological equivalence between the Finsler-Randers space-time and the DGP gravity model

Spyros Basilakos·Panayiotis Stavrinos
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Abstract

We perform a detailed comparison between the Finsler-Randers cosmological model and the Dvali, Gabadadze and Porrati braneworld model. If we assume that the spatial curvature is strictly equal to zero then we prove the following interesting proposition: {\it despite the fact that the current cosmological models have a completely different geometrical origin they share exactly the same Hubble expansion}. This implies that the Finsler-Randers model is cosmologically equivalent with that of the DGP model as far as the cosmic expansion is concerned. At the perturbative level we find that the Finsler-Randers growth index of matter perturbations is $γ_{FR} \simeq 9/14$ which is somewhat lower than that of DGP gravity ($γ_{DGP} \simeq 11/16$) implying that the growth factor of the Finsler-Randers model is slightly different ($\sim 0.1-2%$) from the one provided by the DGP gravity model.

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BibTeXRIS

Spyros Basilakos, Panayiotis Stavrinos. 2013-01-27. Cosmological equivalence between the Finsler-Randers space-time and the DGP gravity model. https://doi.org/10.1103/physrevd.87.043506

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