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arXiv · 1803.08235

Bayesian analysis of bulk viscous matter dominated universe

Athira Sasidharan·N D Jerin Mohan·Moncy V John·Titus K Mathew
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Abstract

In our previous works, we have analyzed the evolution of bulk viscous matter dominated universe with a more general form for bulk viscous coefficient, $ζ=ζ_{0}+ζ_{1}\frac{\dot{a}}{a}+ζ_{2}\frac{\ddot{a}}{\dot{a}}$ and also carried out the dynamical system analysis. We found that the model reasonably describes the evolution of the universe if the viscous coefficient is a constant. In the present work we are contrasting this model with the standard $Λ$CDM model of the universe using the Bayesian method. We have shown that, even though the viscous model gives a reasonable back ground evolution of the universe, the Bayes factor of the model indicates that, it is not so superior over the $Λ$CDM model, but have a slight advantage over it.

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Athira Sasidharan, N D Jerin Mohan, Moncy V John, Titus K Mathew. 2018-04-20. Bayesian analysis of bulk viscous matter dominated universe. https://doi.org/10.1140/epjc%2Fs10052-018-6105-5

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