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arXiv · 1001.3636

LambdaCDM epoch reconstruction from F(R,G) and modified Gauss-Bonnet gravities

Emilio Elizalde·Ratbay Myrzakulov·Valery V. Obukhov·Diego Sáez-Gómez
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Abstract

Dark energy cosmology is considered in a modified Gauss-Bonnet model of gravity with and without a scalar field. It is shown that these generalizations of General Relativity endow it with a very rich cosmological structure: it may naturally lead to an effective cosmological constant, quintessence or phantom cosmic acceleration, with the possibility to describe the transition from a decelerating to an accelerating phase explicitly. It is demonstrated here that these modified GB and scalar-GB theories are perfectly viable as cosmological models. They can describe the LambdaCDM cosmological era without any need for a cosmological constant. Specific properties of these theories of gravity in different particular cases, such as the de Sitter one, are studied.

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Emilio Elizalde, Ratbay Myrzakulov, Valery V. Obukhov, Diego Sáez-Gómez. 2010-01-20. LambdaCDM epoch reconstruction from F(R,G) and modified Gauss-Bonnet gravities. https://doi.org/10.1088/0264-9381%2F27%2F9%2F095007

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