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arXiv · 0905.1468

Cosmic acceleration and crossing of $ω=-1$ in non-minimal modified Gauss-Bonnet gravity

J Sadeghi·M R Setare·A Banijamali
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Abstract

Modified Gauss-Bonnet, i.e, $f(G)$ gravity is a possible explanation of dark energy. Late time cosmology for the $f(G)$ gravity non-minimally coupled with a free massless scalar field have been investigated in Ref. [32]. In this paper we generalize the work of Ref. [32] by including scalar potential in the matter Lagrangian which is non-minimally coupled with modified Gauss-Bonnet gravity. Also we obtain the conditions for having a much more amazing problem than the acceleration of the universe, i.e: crossing of $ω=-1$, in $f(G)$ non-minimally coupled with tachyonic Lagrangian.

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J Sadeghi, M R Setare, A Banijamali. 2009-05-10. Cosmic acceleration and crossing of $ω=-1$ in non-minimal modified Gauss-Bonnet gravity. https://doi.org/10.1016/j.physletb.2009.07.003

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