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arXiv · 1012.0953

f(G) modified gravity and the energy conditions

Nadiezhda Montelongo García·Tiberiu Harko·Francisco S. N. Lobo·José P. Mimoso
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Abstract

Motivated by string/M-theory predictions that scalar field couplings with the Gauss-Bonnet invariant, G, are essential in the appearance of non-singular early time cosmologies, we discuss the viability of an interesting alternative gravitational theory, namely, modified Gauss-Bonnet gravity, and present the viability bounds arising from the energy conditions. In particular, we consider a specific realistic form of f(G) analyzed in the literature that accounts for the late-time cosmic acceleration and that has been found to cure the finite-time future singularities present in the dark energy models, and further examine the respective viability of the specific f(G) model imposed by the weak energy condition.

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Nadiezhda Montelongo García, Tiberiu Harko, Francisco S. N. Lobo, José P. Mimoso. 2010-12-04. f(G) modified gravity and the energy conditions. https://doi.org/10.1088/1742-6596%2F314%2F1%2F012056

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