Anisotropic Plane Symmetric Two-Fluid Cosmological Model with Time-Varying G and Λ

Abstract

We investigate a two-fluid anisotropic plane symmetric cosmological model with variable gravitational constant 𝐺(𝑡) and cosmological term Λ(𝑡). In the two-fluid model, one fluid is chosen to be that of the radiation field modeling the cosmic microwave background and the other one a perfect fluid modeling the material content of the universe. Exact solutions of the field equations are obtained by using a special form for the average scale factor which corresponds to a specific time-varying deceleration parameter. The model obtained presents a cosmological scenario which describes an early acceleration and late-time deceleration. The gravitation constant increases with the cosmic time whereas the cosmological term decreases and asymptotically tends to zero. The physical and kinematical behaviors of the associated fluid parameters are discussed.