Anisotropic dark energy model with a hybrid scale factor

B. Mishra; S. K. Tripathy

doi:10.1142/s0217732315501758

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arXiv · 1507.03515

Anisotropic dark energy model with a hybrid scale factor

B. Mishra·S. K. Tripathy

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Abstract

Anisotropic dark energy model with dynamic pressure anisotropies along different spatial directions is constructed at the backdrop of a spatially homogeneous diagonal Bianchi type $V$ $(BV)$ space-time in the framework of General Relativity. A time varying deceleration parameter generating a hybrid scale factor is considered to simulate a cosmic transition from early deceleration to late time acceleration. We found that the pressure anisotropies along the $y-$ and $z-$ axes evolve dynamically and continue along with the cosmic expansion without being subsided even at late times. The anisotropic pressure along the $x-$axis becomes equal to the mean fluid pressure. At a late phase of cosmic evolution, the model enters into a phantom region. From a state finder diagnosis, it is found that the model overlaps with $Λ$CDM at late phase of cosmic time.

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B. Mishra, S. K. Tripathy. 2015-11-08. Anisotropic dark energy model with a hybrid scale factor. https://doi.org/10.1142/s0217732315501758

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