scholarly journals Crossing the phantom divide line in universal extra dimensions

New Astronomy ◽  
2020 ◽  
Vol 80 ◽  
pp. 101406
Author(s):  
Nasr Ahmed ◽  
Anirudh Pradhan
Keyword(s):  
Extra Dimensions ◽  
Phantom Divide ◽  
Phantom Divide Line

INTERACTING GENERALIZED DARK ENERGY AND RECONSTRUCTION OF SCALAR FIELD MODELS

2013 ◽  
Vol 28 (38) ◽  
pp. 1350180 ◽  
Author(s):  
M. SHARIF ◽  
ABDUL JAWAD
Keyword(s):  
Dark Energy ◽  
Scalar Field ◽  
Dark Energy Model ◽  
Cold Dark Matter ◽  
Scalar Potential ◽  
Scalar Fields ◽  
Phantom Divide ◽  
Evolution Parameter ◽  
Scalar Field Models ◽  
Phantom Divide Line

In this paper, we consider the interacting generalized dark energy with cold dark matter and analyze the behavior of evolution parameter via dark energy and interacting parameters. It is found that the evolution parameter crosses the phantom divide line in most of the cases of integration constants. We also establish the correspondence of scalar field models (quintessence, k-essence and dilaton) with this dark energy model in which scalar fields show the increasing behavior. The scalar potential corresponds to attractor solutions in quintessence case.

scholarly journals CHAMELEON COSMOLOGY MODEL DESCRIBING THE PHANTOM DIVIDE LINE CROSSING

2011 ◽  
Vol 20 (02) ◽  
pp. 121-131 ◽  
Author(s):  
FRANCESCO CANNATA ◽  
ALEXANDER Y. KAMENSHCHIK
Keyword(s):  
Exact Solution ◽  
Scalar Field ◽  
Phantom Divide ◽  
Model Based ◽  
Independent Functions ◽  
Phantom Divide Line ◽  
Line Crossing

An exact solution describing the evolution of the type Bang-to-Rip with the phantom divide line crossing is constructed in the chameleon cosmology model, based on two independent functions of the scalar field.

scholarly journals NETWORKS OF COSMOLOGICAL HISTORIES, CROSSING OF THE PHANTOM DIVIDE LINE AND POTENTIALS WITH CUSPS

2007 ◽  
Vol 16 (10) ◽  
pp. 1683-1704 ◽  
Author(s):  
FRANCESCO CANNATA ◽  
ALEXANDER Y. KAMENSHCHIK
Keyword(s):  
Scalar Field ◽  
Equations Of Motion ◽  
Space Time ◽  
Cosmological Models ◽  
Mechanical Analogy ◽  
Phantom Divide ◽  
Phantom Divide Line

We discuss the phenomenon of the smooth dynamical gravity induced crossing of the phantom divide line in a framework of simple cosmological models where it appears to occur rather naturally, provided the potential of the unique scalar field has some kind of cusp. The behavior of cosmological trajectories in the vicinity of the cusp is studied in some detail and a simple mechanical analogy is presented. The phenomenon of certain complementarity between the smoothness of the space–time geometry and matter equations of motion is elucidated. We introduce a network of cosmological histories and qualitatively describe some of its properties.

scholarly journals Lorenz gauge fixing of f(T) teleparallel cosmology

2017 ◽  
Vol 26 (14) ◽  
pp. 1750154 ◽  
Author(s):  
W. El Hanafy ◽  
G. G. L. Nashed
Keyword(s):  
Degrees Of Freedom ◽  
Teleparallel Gravity ◽  
Phase Portraits ◽  
De Sitter ◽  
Phantom Divide ◽  
Type Iv ◽  
Gauge Fixing ◽  
Phantom Divide Line ◽  
Lorenz Gauge ◽  
The Stability

In teleparallel gravity, we apply Lorenz type gauge fixing to cope with redundant degrees of freedom in the vierbein field. This condition is mainly to restore the Lorentz symmetry of the teleparallel torsion scalar. In cosmological application, this technique provides standard cosmology, turnaround, bounce or [Formula: see text]CDM as separate scenarios. We reconstruct the [Formula: see text] gravity which generates these models. We study the stability of the solutions by analyzing the corresponding phase portraits. Also, we investigate Lorenz gauge in the unimodular coordinates, it leads to unify a nonsingular bounce and Standard Model cosmology in a single model, where crossing the phantom divide line is achievable through a finite-time singularity of Type IV associated with a de Sitter fixed point. We reconstruct the unimodular [Formula: see text] gravity which generates the unified cosmic evolution showing the role of the torsion gravity to establish a healthy bounce scenario.

scholarly journals LATE TIME ACCELERATION IN 3-BRANE BRANS–DICKE COSMOLOGY

2008 ◽  
Vol 23 (36) ◽  
pp. 3095-3111
Author(s):  
A. ERRAHMANI ◽  
T. OUALI
Keyword(s):  
Cosmological Parameters ◽  
Late Time ◽  
Observation Data ◽  
Energy Component ◽  
Phantom Divide ◽  
Big Rip ◽  
Dimensional Spacetime ◽  
Dark Energy Component ◽  
Phantom Divide Line ◽  
The Universe

In order to investigate more features of the Brans–Dicke cosmology in the five-dimensional spacetime, we explore the solutions of its dynamical systems. A behavior of the universe in its early and late time by means of the scale factor is considered. As a result, we show that it is possible to avoid the big rip singularity and to cross the phantom divide line. Furthermore, we review the dark energy component of the universe and its agreement with the observation data for this 3-brane Brans–Dicke cosmology by means of the cosmological parameters.

scholarly journals VISCOUS DARK ENERGY IN f(T) GRAVITY

2013 ◽  
Vol 28 (27) ◽  
pp. 1350118 ◽  
Author(s):  
M. SHARIF ◽  
SHAMAILA RANI
Keyword(s):  
Dark Energy ◽  
Graphical Representation ◽  
Teleparallel Gravity ◽  
Eos Parameter ◽  
Phantom Divide ◽  
Accelerating Expansion ◽  
Phantom Divide Line ◽  
Expansion Of The Universe ◽  
Crossing Of Phantom Divide ◽  
The Universe

We study the bulk viscosity taking dust matter in the generalized teleparallel gravity. We consider different dark energy (DE) models in this scenario along with a time-dependent viscous model to construct the viscous equation of state (EoS) parameter for these DE models. We discuss the graphical representation of this parameter to investigate the viscosity effects on the accelerating expansion of the universe. It is mentioned here that the behavior of the universe depends upon the viscous coefficients showing the transition from decelerating to accelerating phase. It leads to the crossing of phantom divide line and becomes phantom dominated for specific ranges of these coefficients.

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