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arXiv · 0901.0173

Non-Minimal Quintessence With Nearly Flat Potential

Anjan A Sen·Gaveshna Gupta·Sudipta Das
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Abstract

We consider Brans-Dicke type nonminimally coupled scalar field as a candidate for dark energy. In the conformally transformed Einstein's frame, our model is similar to {\it coupled quintessence} model. In such models, we consider potentials for the scalar field which satisfy the slow-roll conditions: $[(1/V)(dV/dϕ)]^2 << 1$ and $(1/V)(d^2V/dϕ^2) << 1$. For such potentials, we show that the equation of state for the scalar field can be described by a universal behaviour, provided the scalar field rolls only in the flat part of the potentials where the slow-roll conditions are satisfied. Our work generalizes the previous work by Scherrer and Sen \cite{scherrer} for minimally coupled scalar field case. We have also studied the observational constraints on the model parameters considering the Supernova and BAO observational data.

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Anjan A Sen, Gaveshna Gupta, Sudipta Das. 2009-01-01. Non-Minimal Quintessence With Nearly Flat Potential. https://doi.org/10.1088/1475-7516%2F2009%2F09%2F027

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