ar X iv : 0 70 4 . 08 49 v 1 [ gr - q c ] 6 A pr 2 00 7 LRS Bianchi Type - V Viscous Fluid Universe With a Time Dependent Cosmological Term Λ
نویسندگان
چکیده
An LRS Bianchi type-V cosmological models representing a viscous fluid distribution with a time dependent cosmological term Λ is investigated. To get a determinate solution, the viscosity coefficient of bulk viscous fluid is assumed to be a power function of mass density. It turns out that the cosmological term Λ(t) is a decreasing function of time, which is consistent with recent observations of type Ia supernovae. Various physical and kinematic features of these models have also been explored. PACS number: 98.80.Es, 98.80.-k
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ar X iv : 0 70 4 . 08 49 v 2 [ gr - q c ] 6 A ug 2 00 7 LRS Bianchi Type - V Viscous Fluid Universe with a Time Dependent Cosmological Term Λ
An LRS Bianchi type-V cosmological models representing a viscous fluid distribution with a time dependent cosmological term Λ is investigated. To get a determinate solution, the viscosity coefficient of bulk viscous fluid is assumed to be a power function of mass density. It turns out that the cosmological term Λ(t) is a decreasing function of time, which is consistent with recent observations ...
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