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arXiv · 1503.06280

Study of non-canonical scalar field model using various parametrizations of dark energy equation of state

Abdulla Al Mamon·Sudipta Das
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Abstract

In this present work, we try to build up a cosmological model using a non-canonical scalar field within the framework of a spatially flat FRW space-time. In this context, we have considered four different parametrizations of the equation of state parameter of the non-canonical scalar field. Under this scenario, analytical solutions for various cosmological parameters have been found out. It has been found that the deceleration parameter shows a smooth transition from a positive value to some negative value which indicates that the universe was undergoing an early deceleration followed by late time acceleration which is essential for the structure formation of the universe. With these four parametrizations, the future evolution of the models are also discussed. It has been found that one of the models (Generalized Chaplygin gas model, GCG) mimics the concordance $Λ$CDM in the near future, whereas two other models (CPL and JBP) diverge due to future singularity. Finally, we have studied these theoretical models with the latest datasets from SN Ia $+$ $H(z)$ $+$ BAO/CMB.

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Abdulla Al Mamon, Sudipta Das. 2015-06-02. Study of non-canonical scalar field model using various parametrizations of dark energy equation of state. https://arxiv.org/abs/1503.06280

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