scholarly journals Interacting agegraphic dark energy models in non-flat universe

2009 ◽  
Vol 680 (2) ◽  
pp. 113-117 ◽  
Author(s):  
Ahmad Sheykhi
Keyword(s):  
Dark Energy ◽  
Agegraphic Dark Energy ◽  
Flat Universe ◽  
Energy Models

Analysis of entropy corrected holographic and new agegraphic dark energy models in generalized Rastall gravity

2020 ◽  
Vol 35 (28) ◽  
pp. 2050175
Author(s):  
Sayani Maity ◽  
Mahasweta Biswas ◽  
Ujjal Debnath
Keyword(s):  
Dark Energy ◽  
Cosmological Parameters ◽  
State Parameter ◽  
Graphical Analysis ◽  
Future Singularity ◽  
Agegraphic Dark Energy ◽  
New Agegraphic Dark Energy ◽  
Energy Models ◽  
Dark Energy Component ◽  
The Stability

This work deals with two fluid system in the framework of generalized Rastall gravity theory. One component represents dark energy whereas the other is dark matter. For the dark energy component, entropy corrected holographic and entropy corrected new agegraphic dark energy models in power-law and logarithmic versions are taken into account. For this study, we assume two classes of scale factors in which one corresponds to the future singularity and another corresponds to the initial singularity. For each of the entropy corrected dark energy models, the cosmological parameters such as Hubble parameter, deceleration parameter and equation of state parameter are calculated and their implications are established. Furthermore, to describe the stability analysis of the models, the behaviors of the squared speed of sound are analyzed graphically for each of these models. From the graphical analysis of [Formula: see text] plane, the thawing or freezing regions of all the models are determined.

scholarly journals Tsallis agegraphic dark energy model

2019 ◽  
Vol 34 (11) ◽  
pp. 1950086 ◽  
Author(s):  
M. Abdollahi Zadeh ◽  
A. Sheykhi ◽  
H. Moradpour
Keyword(s):  
Dark Energy ◽  
Equation Of State ◽  
Dark Energy Model ◽  
Late Time ◽  
Conformal Time ◽  
Classical Level ◽  
Agegraphic Dark Energy ◽  
Energy Models ◽  
Age Of The Universe ◽  
The Universe

Using the non-extensive Tsallis entropy and the holographic hypothesis, we propose a new dark energy (DE) model with timescale as infrared (IR) cutoff. Considering the age of the Universe as well as the conformal time as IR cutoffs, we investigate the cosmological consequences of the proposed DE models and study the evolution of the Universe filled by a pressureless matter and the obtained DE candidates. We find that although this model can describe the late time acceleration and the density, deceleration and the equation of state parameters show satisfactory behavior by themselves, these models are classically unstable unless the interaction between the two dark sectors of the Universe is taken into account. In addition, the results of the existence of a mutual interaction between the cosmos sectors are also addressed. We find out that the interacting models are stable at the classical level which is in contrast to the original interacting agegraphic dark energy models which are classically unstable [K. Y. Kim, H. W. Lee and Y. S. Myung, Phys. Lett. B 660, 118 (2008)].

NEW AGEGRAPHIC CHAPLYGIN GAS MODEL WITH VISCOSITY

2011 ◽  
Vol 26 (10) ◽  
pp. 727-737 ◽  
Author(s):  
LEI WANG ◽  
YA-BO WU ◽  
LEI LI ◽  
YUAN GAO ◽  
JIAN GAO
Keyword(s):  
Dark Energy ◽  
Scalar Field ◽  
Chaplygin Gas ◽  
Generalized Chaplygin Gas ◽  
Agegraphic Dark Energy ◽  
New Agegraphic Dark Energy ◽  
Flat Universe ◽  
Special Case

In this paper, motivated by Ref. 31, we study the so-called new agegraphic Chaplygin gas model with viscosity. Concretely, we establish the correspondence between the interacting new agegraphic dark energy (NADE) and variable generalized Chaplygin gas (VGCG) models in non-flat universe on the basis of reviewing related contents for the NADE and VGCG models. Furthermore, we reconstruct the potential of the new agegraphic scalar field as well as the dynamics of the scalar field according to the evolution of the agegraphic dark energy. Finally, we generalize our study to the case of NADE with viscosity, which includes the case without viscosity (ν = 0) as a special case.

CORRESPONDENCE BETWEEN 5D RICCI-FLAT COSMOLOGICAL MODELS AND QUINTESSENCE DARK ENERGY MODELS

2005 ◽  
Vol 20 (40) ◽  
pp. 3105-3114 ◽  
Author(s):  
LIXIN XU ◽  
HONGYA LIU ◽  
BAORONG CHANG
Keyword(s):  
Dark Energy ◽  
Arbitrary Function ◽  
Big Bang ◽  
Cosmological Models ◽  
Ricci Flat ◽  
Flat Universe ◽  
Energy Models ◽  
Accelerating Expansion ◽  
Big Bounce

We study the accelerating expansion and the induced dark energy of the 5D Ricci-flat universe which is characterized by having a big bounce as opposed to a big bang. We show that the arbitrary function μ(t) contained in the 5D solutions can be rewritten in terms of the redshift z as a new arbitrary function f(z), and we find that there is a correspondence between this f(z) and the potential V(ϕ) of the 4D quintessence models. Using this correspondence, the arbitrary function f(z) and the 5D solution could be specified for a given form of the potential V(ϕ).

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