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arXiv · 1211.3457

Quintessential and phantom power-law solutions in scalar tensor model of dark energy

L. N. Granda·D. F. Jimenez·C. Sanchez
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Abstract

We consider a scalar-tensor model of dark energy with kinetic and Gauss Bonnet couplings. We study the conditions for the existence of quintessential and phantom power-law expansion, and also analyze these conditions in absence of potential (closely related to string theory). A mechanism to avoid the Big Rip singularity in various asymptotic limits of the model has been studied. It was found that the kinetic and Gauss-Bonnet couplings might prevent the Big Rip singularity in a phantom scenario. The autonomous system for the model has been used to study the stability properties of the power-law solution, and the centre manifold analysis was used to treat zero eigenvalues.

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L. N. Granda, D. F. Jimenez, C. Sanchez. 2012-11-14. Quintessential and phantom power-law solutions in scalar tensor model of dark energy. https://doi.org/10.1142/s0218271813500557

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