scholarly journals QCD Ghost Dark Energy in Fractal Cosmology

2017 ◽  
Vol 1 (1) ◽  
pp. 34-43 ◽  
Author(s):  
Ines G. Salako ◽  
◽  
Faiza Gulshan ◽  
Keyword(s):  
Dark Energy ◽  
Ghost Dark Energy ◽  
Qcd Ghost Dark Energy

scholarly journals QCD ghost dark energy cannot (even roughly) explain the main features of the accepted cosmological paradigm

2013 ◽  
Vol 88 (4) ◽  
Author(s):  
Ricardo García-Salcedo ◽  
Tame Gonzalez ◽  
Israel Quiros ◽  
Michael Thompson-Montero
Keyword(s):  
Dark Energy ◽  
Ghost Dark Energy ◽  
Qcd Ghost Dark Energy

Study of anisotropy effects on QCD ghost dark energy using the cosmological data

2020 ◽  
Vol 365 (3) ◽  
Author(s):  
H. Hossienkhani ◽  
H. Yousefi ◽  
N. Azimi ◽  
Z. Zarei
Keyword(s):  
Dark Energy ◽  
Ghost Dark Energy ◽  
Cosmological Data ◽  
Qcd Ghost Dark Energy

scholarly journals More on QCD ghost dark energy

2012 ◽  
Vol 86 (2) ◽  
Author(s):  
Rong-Gen Cai ◽  
Zhong-Liang Tuo ◽  
Ya-Bo Wu ◽  
Yue-Yue Zhao
Keyword(s):  
Dark Energy ◽  
Ghost Dark Energy ◽  
Qcd Ghost Dark Energy

scholarly journals COSMOGRAPHY OF INTERACTING GENERALIZED QCD GHOST DARK ENERGY

2013 ◽  
Vol 22 (14) ◽  
pp. 1350084 ◽  
Author(s):  
MOHAMMAD MALEKJANI
Keyword(s):  
Dark Matter ◽  
Dark Energy ◽  
Accelerated Expansion ◽  
Model Parameter ◽  
Ghost Dark Energy ◽  
Evolutionary Trajectories ◽  
Expansion Of The Universe ◽  
Qcd Ghost Dark Energy ◽  
The Universe ◽  
Friedmann Robertson Walker

Exploring the accelerated expansion of the universe, we investigate the generalized ghost dark energy (GGDE) model from the statefinder diagnostic analysis in a flat Friedmann–Robertson–Walker universe. First, we calculate the cosmological evolution and statefinder trajectories for noninteracting case and then extend this work by considering the interaction between dark matter and dark energy components. We show that in the noninteracting case the phantom line cannot be crossed and also the evolutionary trajectories of model in s - r plane cannot be discriminated. It has been shown that the present location of model in s - r plane would be close to observational value for negative values of the model parameter. In the presence of interaction between dark matter and dark energy, the phantom regime is achieved, the accelerated phase of expansion occurs sooner compared with the noninteracting case. The GGDE model is also discussed from the viewpoint of perturbation theory by calculating the adiabatic sound speed of the model. Finally, unlike the noninteracting case, the evolutionary trajectories in s - r plane can be discriminated in the interacting model. Like the noninteracting model, in the interacting case the present location of GGDE model is closer to observational value for negative values of the model parameter.

scholarly journals INSTABILITY OF QCD GHOST DARK ENERGY MODEL

2011 ◽  
Vol 20 (12) ◽  
pp. 2369-2381 ◽  
Author(s):  
ESMAEIL EBRAHIMI ◽  
AHMAD SHEYKHI
Keyword(s):  
Dark Energy ◽  
Perfect Fluid ◽  
Sound Speed ◽  
Dark Energy Model ◽  
Coupling Parameter ◽  
Energy Model ◽  
Frw Universe ◽  
Ghost Dark Energy ◽  
The Stability ◽  
Qcd Ghost Dark Energy

We investigate the instability of the ghost dark energy model against perturbations in different cases. To this goal we use the squared sound speed [Formula: see text] whose sign determines the stability of the model. When [Formula: see text] the model is unstable against perturbation. At first we discuss the noninteracting ghost dark energy model in a flat FRW universe and find out that such a model is unstable due to the negativity of the [Formula: see text] in all epoches. The interacting ghost dark energy model in both flat and nonflat universe are studied in the next parts and in both cases we find that the squared sound speed of ghost dark energy is always negative. This implies that the perfect fluid for ghost dark energy is classically unstable against perturbations. In both flat and non flat cases we find that the instability of the model increases with increasing the value of the interacting coupling parameter.

scholarly journals Consistency of nonlinear interacting ghost dark energy with recent observations

2017 ◽  
Vol 26 (11) ◽  
pp. 1750124 ◽  
Author(s):  
E. Ebrahimi ◽  
H. Golchin ◽  
A. Mehrabi ◽  
S. M. S. Movahed
Keyword(s):  
Dark Energy ◽  
Observational Data ◽  
Nonlinear Interaction ◽  
Acoustic Oscillation ◽  
Joint Analysis ◽  
Data Sets ◽  
Dark Energy Density ◽  
Ghost Dark Energy ◽  
Interaction Terms ◽  
Best Fit

In this paper, we investigate ghost dark energy model in the presence of nonlinear interaction between dark energy and dark matter. We also extend the analysis to the so-called generalized ghost dark energy (GGDE) which [Formula: see text]. The model contains three free parameters as [Formula: see text] and [Formula: see text] (the coupling coefficient of interactions). We propose three kinds of nonlinear interaction terms and discuss the behavior of equation of state, deceleration and dark energy density parameters of the model. We also find the squared sound speed and search for signs of stability of the model. To compare the interacting GGDE model with observational data sets, we use more recent observational outcomes, namely SNIa from JLA catalog, Hubble parameter, baryonic acoustic oscillation and the most relevant CMB parameters including, the position of acoustic peaks, shift parameters and redshift to recombination. For GGDE with the first nonlinear interaction, the joint analysis indicates that [Formula: see text], [Formula: see text] and [Formula: see text] at 1 optimal variance error. For the second interaction, the best fit values at [Formula: see text] confidence are [Formula: see text], [Formula: see text] and [Formula: see text]. According to combination of all observational data sets considered in this paper, the best fit values for third nonlinearly interacting model are [Formula: see text], [Formula: see text] and [Formula: see text] at [Formula: see text] confidence interval. Finally, we found that the presence of interaction is compatible in mentioned models via current observational datasets.

Anisotropic ghost dark energy cosmological model with hybrid expansion law

New Astronomy ◽  
2017 ◽  
Vol 57 ◽  
pp. 70-75 ◽  
Author(s):  
Chandra Rekha Mahanta ◽  
Nitin Sarma
Keyword(s):  
Dark Energy ◽  
Cosmological Model ◽  
Ghost Dark Energy
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