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arXiv · 1109.2332

Modified geodetic brane cosmology

Rubén Cordero·Miguel Cruz·Alberto Molgado·Efraín Rojas
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Abstract

We explore the cosmological implications provided by the geodetic brane gravity action corrected by an extrinsic curvature brane term, describing a codimension-1 brane embedded in a 5D fixed Minkowski spacetime. In the geodetic brane gravity action, we accommodate the correction term through a linear term in the extrinsic curvature swept out by the brane. We study the resulting geodetic-type equation of motion. Within a Friedmann-Robertson-Walker metric, we obtain a generalized Friedmann equation describing the associated cosmological evolution. We observe that, when the radiation-like energy contribution from the extra dimension is vanishing, this effective model leads to a self-(non-self)-accelerated expansion of the brane-like universe in dependence on the nature of the concomitant β-parameter associated with the correction, which resembles an analogous behaviour in the DGP brane cosmology. Several possibilities in the description for the cosmic evolution of this model are embodied and characterized by the involved density parameters related in turn to the cosmological constant, the geometry characterizing the model, the introduced β-parameter as well as the dark like-energy and the matter content on the brane.

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Rubén Cordero, Miguel Cruz, Alberto Molgado, Efraín Rojas. 2012-08-22. Modified geodetic brane cosmology. https://doi.org/10.1088/0264-9381%2F29%2F17%2F175010

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