Constraining the bulk viscous coefficients in a viscous universe with cosmological constant
Abstract
In this paper we consider dissipative effects in $\Lambda$CDM model, i.e., we consider a universe with cosmological constant having viscous matter. We assume the most general form for bulk viscous coefficient, $\zeta=\zeta_{0}+\zeta_{1}\frac{\dot{a}}{a}+\zeta_{2}\frac{\ddot{a}}{\dot{a}}$ and obtained various constrains for $\zeta$'s . We also studied the background study of the model with $\zeta=\zeta_{0}$ and $\zeta=\zeta_{1}\frac{\dot{a}}{a}$. Extracted the value of $\zeta_1$ using the Pantheon data and also obtained its thermodynamic evolution and the age.
- Publication:
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arXiv e-prints
- Pub Date:
- July 2023
- DOI:
- 10.48550/arXiv.2307.05576
- arXiv:
- arXiv:2307.05576
- Bibcode:
- 2023arXiv230705576S
- Keywords:
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- General Relativity and Quantum Cosmology
- E-Print:
- 12 pages 5 figures