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arXiv · 2107.02536

Accelerating Universe with binary mixture of bulk viscous fluid and dark energy

Nishant Singla·M. K. Gupta·Anil Kumar Yadav·G. K. Goswami
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Abstract

In this paper, we have proposed a model of accelerating Universe with binary mixture of bulk viscous fluid and dark energy. and probed the model parameters: present values of Hubble's constant $H_{0}$, Equation of state paper of dark energy $ω_{de}$ and density parameter of dark energy $(Ω_{de})_{0}$ with recent OHD as well as joint Pantheon compilation of SN Ia data and OHD. Using cosmic chronometric technique, we obtain $H_{0} = 69.80 \pm 1.64~km~s^{-1}Mpc^{-1}$ and $70.0258 \pm 1.72~km~s^{-1}Mpc^{-1}$ by restricting our derived model with recent OHD and joint Pantheon compilation SN Ia data and OHD respectively. The age of the Universe in derived model is estimated as $t_{0} = 13.82 \pm 0.33\; Gyrs$. Also, we observe that derived model represents a model of transitioning Universe with transition redshift $z_{t} = 0.7286$. We have constrained the present value of jerk parameter as $j_{0} = 0.969 \pm 0.0075$ with joint OHD and Pantheon data. From this analysis, we observed that the model of the Universe, presented in this paper shows a marginal departure from $Λ$CDM model.

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Nishant Singla, M. K. Gupta, Anil Kumar Yadav, G. K. Goswami. 2021-07-06. Accelerating Universe with binary mixture of bulk viscous fluid and dark energy. https://doi.org/10.1142/s0217751x21501487

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