Unified dark fluid and cosmic transit models in Brans–Dicke theory
Apr 1, 2020
17 pages
Published in:
- Phys.Dark Univ. 30 (2020) 100722
- Published: Dec, 2020
e-Print:
- 2004.01027 [gr-qc]
View in:
Citations per year
Abstract: (Elsevier)
Some dark energy cosmological models are constructed in the framework of a generalised Brans–Dicke theory which contains a self interacting potential and a dynamical coupling parameter. The models are constructed in the background of an anisotropic metric. The dark sector of the universe is considered through a unified linear equation of state. The parameters of the unified dark fluid have been constrained from some physical basis. Since the universe is believed to have undergone a transition from an early deceleration to a late time acceleration, the deceleration parameter should have a signature flipping behaviour at the transition redshift. We have used a hybrid scale factor to simulate the dynamical behaviour of the deceleration parameter. Basing upon the observational constraints on the transition redshift, we have constructed four different transitioning dark energy models. The constructed models are confronted with observational data. For all the models, the behaviour of the dynamical scalar field, Brans–Dicke parameter are investigated. Also, on the basis of the generalised Brans–Dicke theory, we have estimated the time variation of the Newtonian gravitational constant.Note:
- 17pages, 12 figures
- Unified dark fluid
- Generalised Brans–Dicke theory
- Hybrid scale factor
- redshift: transition
- equation of state: linear
- gravitation: fundamental constant
- field theory: scalar
- Brans-Dicke model
- expansion: deceleration
- dark energy
References(113)
Figures(12)
- [1]
- [2]
- [3]
- [4]
- [7]
- [6]
- [7]
- [8]
- [9]
- [10]
- [11]
- [12]
- [13]
- [14]
- [15]
- [16]
- [17]
- [18]
- [19]
- [20]
- [21]
- [22]
- [23]
- [24]
- [25]