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arXiv · 1108.2133

Two-Fluid Scenario for Dark Energy Models in an FRW Universe-Revisited

Bijan Saha·Hassan Amirhashchi·Anirudh Pradhan
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Abstract

In this paper we study the evolution of the dark energy parameter within the scope of a spatially homogeneous and isotropic Friedmann-Robertson-Walker (FRW) model filled with barotropic fluid and dark energy by revisiting the recent results (Amirhashchi et al. in Chin. Phys. Lett. 28:039801, 2011a). To prevail the deterministic solution we select the scale factor $a(t) = \sqrt{t^{n}e^{t}}$ which generates a time-dependent deceleration parameter (DP), representing a model which generates a transition of the universe from the early decelerating phase to the recent accelerating phase. We consider the two cases of an interacting and non-interacting two-fluid (barotropic and dark energy) scenario and obtained general results. The cosmic jerk parameter in our derived model is also found to be in good agreement with the recent data of astrophysical observations under the suitable condition. The physical aspects of the models and the stability of the corresponding solutions are also discussed.

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Bijan Saha, Hassan Amirhashchi, Anirudh Pradhan. 2012-07-02. Two-Fluid Scenario for Dark Energy Models in an FRW Universe-Revisited. https://doi.org/10.1007/s10509-012-1155-x

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