Higher Dimensional Bianchi Type-III String Cosmological Models in Lyra Geometry

Here we studied Bianchi type-III string cosmological models generated by means of a cloud of strings with particles connected to them in the framework of Lyra geometry considering five-dimensional space-time. To obtain the exact solutions of field equations we consider that the shear scalar and the scalar expansion are proportional, σ∞θ which leads to D=cn and secondly we adopt the assumption considering the Reddy String Condition, ρ+λ=0. From the two different cases obtained here, first case leads to the Bianchi type-III string cosmological model in Lyra geometry in five-dimensional space-time and the second case leads to the five-dimensional vacuum universe in general relativity. The Geometrical and physical properties of the model universe are studied comparing with the present day’s observational findings. The model universe obtained here starts with the big bang and as time progresses both particle density ρp and energy density ρ decreases with expansion of our Universe.

Tilted universe with big rip singularity in Lyra geometry

We have examined tilted cosmological models by using conformally flat space-time with wet dark fluid in Lyra geometry. In order to solve the field equations we have considered a power law. In this paper we have discussed tilted universe with time-dependent displacement field vector, heat conduction vectors and also discussed big rip singularity. Some physical and geometrical properties are also investigated. We have also extended our work to investigate the consistency of the derived model with observational parameter from the point of astrophysical phenomenon such as look-back time-redshift, proper distance, luminosity distance, angular-diameter distance and distance modulus.