ar X iv : 0 70 5 . 04 59 v 1 [ gr - q c ] 3 M ay 2 00 7 Bianchi Type - I Cosmological Models with Variable G and Λ - Term in General Relativity
نویسنده
چکیده
Einstein’s field equations with variable gravitational and cosmological “constant” are considered in presence of perfect fluid for Bianchi type-I spacetime. Consequences of the four cases of the phenomenological decay of Λ have been discussed which are consistent with observations. The physical significance of the cosmological models have also been discussed. PACS: 98.80.Es, 98.80.-k
منابع مشابه
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
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 ...
متن کاملar 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 ...
متن کاملBulk Viscous Bianchi Type VI0 Cosmological Model in the Self-creation Theory of Gravitation and in the General Theory of Relativity
In the second self-creation theory of gravitation and in the general theory of relativity, Bianchi type VI0 cosmological model in the presence of viscous fluid is studied. An exact solution of the field equations is given by considering the cosmological model yields a constant decelerations parameter q=constant and the coefficients of the metric are taken as A(t)=[c1t+c<su...
متن کاملar X iv : 0 70 5 . 45 49 v 1 [ gr - q c ] 3 1 M ay 2 00 7 Quantum - theoretical description of the cosmological constant as the zero - point energy
The present paper seeks to construct a quantum theory of the cosmological constant in which its presently observed very small value emerges naturally. Large scale cosmological observations over the past decade (see references cited in [1], and [2-4]) have provided data which are in accord with the simplest cosmological model LCDM (Λ + Cold Dark Matter) [4-7]. This model is governed by the homog...
متن کاملar X iv : 0 80 7 . 38 04 v 1 [ gr - q c ] 2 4 Ju l 2 00 8 Wave - like Solutions for Bianchi type - I cosmologies in 5 D
We derive exact solutions to the vacuum Einstein field equations in 5D, under the assumption that (i) the line element in 5D possesses self-similar symmetry, in the classical understanding of Sedov, Taub and Zeldovich, and that (ii) the metric tensor is diagonal and independent of the coordinates for ordinary 3D space. These assumptions lead to three different types of self-similarity in 5D: ho...
متن کامل