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arXiv · 1503.07420

Constraints on The Dark Energy Equation of State And The Deceleration Parameter From Recent Cosmic Observations

Hassan Amirhashchi
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Abstract

We study the constraints on dark energy equation of state $ω^{X}$ and the deceleration parameter $q$ from the recent observational data including Hubble data and the cosmic microwave background (CMB) radiation by using a model-independent deceleration parameter $q(z)=1/2-a/(1+z)^b$ and dark energy equation of state $ω^{X}=ω_{0}+ω_{1}z/(1+z)$ in the scope of anisotropic Bianchi type I space-time. For the cases of Hubble dataset, CMB data, and their combination, our results indicate that the constraints on transition redshift $z_{\ast}$ are $0.62^{+1.45}_{-0.56}$, $0.34^{+0.13}_{-0.06}$, and $0.60^{+0.20}_{-0.10}$ respectively.

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Hassan Amirhashchi. 2015-03-22. Constraints on The Dark Energy Equation of State And The Deceleration Parameter From Recent Cosmic Observations. https://arxiv.org/abs/1503.07420

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