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arXiv · 1011.5709

L.R.S. Bianchi type II Stiff Fluid cosmological model with Decaying Vacuum Energy Density $\Lambda$ in general relativity

Hassan Amirhashchi
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Abstract

Locally rotationally symmetric (L.R.S.) Bianchi type II stiff fluid cosmological model is investigated. To get the deterministic model of the universe, we have assumed a condition $A=B^{m}$ between metric potentials $A,~B$ where $n$ is the constant. It is shown that the vacuum energy density $\Lambda$ is positive and proportional to $\frac{1}{t^{2}}$. The values of deceleration parameter $q$, matter-energy density $\Omega_{m}$ and dark-energy density $\Omega_{\Lambda}$ are found to be in good agreement with the values obtain from 5-years WMAP observations. the predicted value of the jerk parameter agrees with the SNLS SNIa and X-ray galaxy cluster distance data but does not with the SNIa gold sample data. In general, the model represent accelerating, shearing and non-rotating universe.The physical and geometrical behavior of these models are also discussed.

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Hassan Amirhashchi. 2010-11-26. L.R.S. Bianchi type II Stiff Fluid cosmological model with Decaying Vacuum Energy Density $\Lambda$ in general relativity. https://doi.org/10.1016/j.physletb.2011.02.046

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