Bianchi type-V Space-time Research Articles

The Bianchi type-V vacuum cosmological model in the scale covariant theory

A solution of the field equations in the scale-covariant theory for a Bianchi type-V spacetime is obtained. It is shown that this solution represents a generalization of the general relativistic one.

Scalar fields, fluids and exact Bianchi type-V solutions

The Einstein field equations for a Bianchi type-V spacetime are solved in the case that the energy-momentum tensor is constructed from two massless scalar fields. This solution can be interpreted as representing an anisotropic fluid.

A tilted Bianchi type-V perfect fluid solution for stiff matter

We present a solution to the Einstein field equations for a massless scalar field in a Bianchi type-V spacetime, which can be interpreted as a solution for a perfect fluid with the equation of state of stiff matter. This solution complements a solution previously given by us for an anisotropic fluid.

Electromagnetic Brans-Dicke-Bianchi type-V solutions

We derive new solutions for the locally rotational-symmetric Bianchi type-V space-time in the Brans-Dicke theory of gravitation. The solutions represent anisotropic cosmological models filled with ‘stiff’ matter and an electromagnetic null field, including the vacuum case. It is shown that the scalar field ϕ is dynamically an essential factor, since it influences the structure of the singularities and the expansion of the models.

Locally rotationally symmetric cosmological model containing a nonrotationally symmetric electromagnetic field

The Einstein-Maxwell equations are integrated for a locally rotationally symmetric, Bianchi type-V spacetime containing a source-free, null, electromagnetic field. Solutions are also given for an added, noninteracting component with equation of state $P=\ensuremath{\rho}$. A striking feature of the models is that the rotational symmetry of the spatially homogeneous geometry is not shared by the electromagnetic field. Field components orthogonal to the symmetry axis define preferred directions, breaking rotational symmetry. The effects of matter and the electromagnetic field on the singularity structure are also examined. It is found that although the ratio of electromagnetic energy density to mass energy density approaches zero as the singularity is approached, the electromagnetic field influences the nature of the singularity.