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arXiv · 0905.2348

Non-minimal quintessence and phantom with nearly flat potentials

Gaveshna Gupta·Emmanuel N. Saridakis·Anjan A. Sen
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Abstract

We investigate quintessence and phantom dark energy scenarios, in which the scalar fields evolve in nearly flat potentials and are non-minimally coupled to gravity. We show that all such models converge to a common behavior and we provide the corresponding approximate analytical expressions for $w(Ω_ϕ)$ and $w(a)$. We find that non-minimal coupling leads to richer cosmological behavior comparing to its minimal counterpart. In addition, comparison with Baryon Acoustic Oscillation and latest Supernovae data reveals that agreement can be established more easily and with less strict constraints on the model parameters.

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Gaveshna Gupta, Emmanuel N. Saridakis, Anjan A. Sen. 2009-06-11. Non-minimal quintessence and phantom with nearly flat potentials. https://doi.org/10.1103/physrevd.79.123013

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