Dergiler / Turkish Journal of Physics / 2009 / Cilt: 33 - Sayı: 3
Kantowski-Sachs viscous fluid cosmological model with a varying L
- Sayfa
- 155–165
- DOI
- —
Özet
We study the Kantowski-Sachs cosmological model filled with viscous fluid in the presence of cosmological term L. To get a deterministic solution, a condition between metric potentials is used. The viscous coefficient of bulk viscous fluid is assumed to be a power function of mass density, whereas coefficient of shear viscosity is considered proportional to scale of expansion in the model. It is found that the cosmological constant L is positive and is a decreasing function of time, which is supported by results from recent supernova observations. Some physical and geometrical properties of the models are also discussed.
Abstract
We study the Kantowski-Sachs cosmological model filled with viscous fluid in the presence of cosmological term L. To get a deterministic solution, a condition between metric potentials is used. The viscous coefficient of bulk viscous fluid is assumed to be a power function of mass density, whereas coefficient of shear viscosity is considered proportional to scale of expansion in the model. It is found that the cosmological constant L is positive and is a decreasing function of time, which is supported by results from recent supernova observations. Some physical and geometrical properties of the models are also discussed.