Anisotropic dark energy model with a hybrid scale factor

Abstract

Anisotropic dark energy model with dynamic pressure anisotropies along different spatial directions is constructed at the backdrop of a spatially homogeneous diagonal Bianchi type V (BV ) space-time in the framework of General Relativity. A time varying deceleration parameter generating a hybrid scale factor is considered to simulate a cosmic transition from early deceleration to late time acceleration. We found that the pressure anisotropies along the y− and z− axes evolve dynamically and continue along with the cosmic expansion without being subsided even at late times. The anisotropic pressure along the x−axis becomes equal to the mean fluid pressure. At a late phase of cosmic evolution, the model enters into a phantom region. From a statefinder diagnosis, it is found that the model overlaps with ΛCDM at late phase of cosmic time.

Could the Lyra manifold be the hidden source of the dark energy?

“…While the power law behaviour dominate the cosmic dynamics in early phase of cosmic evolution, the exponential factor dominates at late phase. When a = 0, the exponential law is recovered and for 1/b = 0, the scale factor reduces to the power law as suggested by Mishra [76] and Akarsu et al [77]. Here we are very much interested in a transient universe with early deceleration and late acceleration so that at early time q can be positive whereas at late time q assumes a negative value in conformity with the recent observational data.…”

Two-fluid scenario in Bianchi type-I universe

“…model. In another papers [11,12], they have also discussed Bulk viscous embedded BT-I dark energy models. Recently Rashid et al [13] have also developed anisotropic DE model.…”

Axially magnetized dark energy cosmological model

“…To investigate the dynamical and anisotropic behaviour along different directions, we adopt here the mathematical formalism developed in [23]. Now, with an axially placed magnetic field and DE, we reveal the dynamical properties of the cosmological model.…”

“…Now, with an axially placed magnetic field and DE, we reveal the dynamical properties of the cosmological model. To do that we have taken an anisotropic relationship between the metric potentials as b = c m [23,44]. Here m should not be unity in order to avoid the isoptropic behaviour of the model.…”

“…Brevik et al [22] constructed cosmological models by establishing an interaction between the DE and dark matter with a homogeneous equation of state parameter. In contract to constant deceleration parameter, Mishra and Tripathy [23] considered time varying deceleration parameter to construct DE cosmological model in an anisotropic metric. Saadeh et al [24] have presented a new framework to search for any departures from isotropic background in Bianchi type V II h cosmologies.…”