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

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 نشر من قبل Anil Yadav dr
 تاريخ النشر 2021
  مجال البحث فيزياء
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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 Hubbles constant $H_{0}$, Equation of state paper of dark energy $omega_{de}$ and density parameter of dark energy $(Omega_{de})_{0}$ 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 $Lambda$CDM model.



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