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Dark energy in modified Gauss-Bonnet gravity: late-time acceleration and the hierarchy problem

Guido Cognola·Emilio Elizalde·Shin'ichi Nojiri·Sergei D. Odintsov·Sergio Zerbini
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Abstract

Dark energy cosmology is considered in a modified Gauss-Bonnet (GB) model of gravity where an arbitrary function of the GB invariant, $f(G)$, is added to the General Relativity action. We show that such theory is endowed with a quite rich cosmological structure: it may naturally lead to an effective cosmological constant, quintessence or phantom cosmic acceleration, with a possible transition from deceleration to acceleration. It is demonstrated in the paper that this theory is perfectly viable, since it is compliant with Solar System constraints. Specific properties of $f(G)$ gravity in a de Sitter universe, such as dS and SdS solutions, their entropy and its explicit one-loop quantization are studied. The issue of a possible solution of the hierarchy problem in modified gravities is addressed too.

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Guido Cognola, Emilio Elizalde, Shin'ichi Nojiri, Sergei D. Odintsov, Sergio Zerbini. 2006-03-01. Dark energy in modified Gauss-Bonnet gravity: late-time acceleration and the hierarchy problem. https://doi.org/10.1103/physrevd.73.084007

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