In this paper, we investigate Bianchi type − V cosmological models with bulk viscous fluid and time varying Λ Newtonian G parameters. The Einstein’s field equations have been transformed into a coupling non-linear, first-order differential equations, the fourth-order Runge-Kutta method of numerical integration has used to integrate appropriate initial conditions consistent current observations....

Abstract. I study the dynamical effects due to the Brans-Dicke scalar φ-field at the early stages of a supposedly anisotropic Universe expansion in the scalar-tensor cosmology of Jordan-Brans-Dicke. This is done considering the behaviour of the general solutions for the homogeneous model of Bianchi type VII in the vacuum case. I conclude that the Bianchi-VII0 model shows an isotropic expansion ...

We consider the asymptotic dynamics of the EinsteinMaxwell field equations for the class of non-tilted Bianchi cosmologies with a barotropic perfect fluid and a pure homogeneous sourcefree magnetic field, with emphasis on models of Bianchi type VII0, which have not been previously studied. Using the orthonormal frame formalism and Hubble-normalized variables, we show that, as is the case for th...

In this paper we investigate expanding Bianchi type I models with two tilted fluids with the same linear equation of state, characterized by the equation of state parameter w. Individually the fluids have non-zero energy fluxes w.r.t. the symmetry surfaces, but these cancel each other because of the Codazzi constraint. We prove that when w = 0 the model isotropizes to the future. Using numerica...

We investigate cosmologies where the accelerated expansion of the Universe is driven by a field with an anisotropic equation of state. We model such scenarios within the Bianchi I framework, introducing two skewness parameters to quantify the deviation of pressure from isotropy. We study the dynamics of the background expansion in these models. A special case of anisotropic cosmological constan...

Loop quantum cosmological methods are extended to homogeneous models in diagonalized form. It is shown that the diagonalization leads to a simplification of the volume operator such that its spectrum can be determined explicitly. This allows the calculation of composite operators, most importantly the Hamiltonian constraint. As an application the dynamics of the Bianchi I model is studied and i...