scholarly journals Power-law entropy-corrected new agegraphic dark energy in Hořava–Lifshitz cosmology

2012 ◽  
Vol 90 (5) ◽  
pp. 473-479 ◽  
Author(s):  
K. Karami ◽  
A. Sheykhi ◽  
M. Jamil ◽  
R. Myrzakulov ◽  
S. Ghaffari ◽  
...  
Keyword(s):  
Dark Energy ◽  
Power Law ◽  
Dark Energy Model ◽  
Coupling Parameter ◽  
State Parameter ◽  
Density Parameter ◽  
Agegraphic Dark Energy ◽  
New Agegraphic Dark Energy ◽  
Corrected Entropy ◽  
Interacting Dark Energy Model

We investigate the new agegraphic dark energy (NADE) model with power-law corrected entropy in the framework of Hořava–Lifshitz cosmology. For a nonflat universe containing the interacting power-law entropy-corrected NADE with dark matter, we obtain the differential equation of the evolution of the density parameter as well as the deceleration parameter. To study parametric behavior, we use an interesting form of state parameter as a function of redshift ωΛ(z) = ω0 + ω1z. We find that phantom crossing occurs for the state parameter for a nonzero coupling parameter, thus supporting the interacting dark energy model.

scholarly journals Evolution of non-flat cosmos via GGPDE f(R) model

2020 ◽  
Vol 80 (2) ◽  
Author(s):  
Wajiha Javed ◽  
Iqra Nawazish ◽  
Fatima Shahid ◽  
Nimra Irshad
Keyword(s):  
Dark Energy ◽  
Power Law ◽  
Dark Energy Model ◽  
Cosmological Parameters ◽  
State Parameter ◽  
Scale Factor ◽  
Energy Model ◽  
Density Parameter ◽  
Shift Parameter ◽  
Scale Factors

Abstract This paper is devoted to explore the cosmic evolution of non-flat Friedmann Robertson Walker universe through generalized ghost pilgrim dark energy model in the background of f(R) gravity. For this purpose, we consider two well known scale factors, i.e., power-law and unified scale factors in terms of red shift parameter. For these scale factors, we reconstruct the given dark energy model in f(R) gravity and determine its stability/instability through squared speed of sound parameter. In order to discuss the behavior of reconstructed and dark energy models, we evaluate well known cosmological parameter such as equation of state parameter along with $$\omega $$ω–$$\omega '$$ω′ plane. In addition to this, we also investigate compatibility of new models with standard cosmological models through state-finder parameters. The density parameter is formulated for both ordinary matter as well as dark energy components and results are compared with Planck 2018 constraints. It is concluded that cosmological parameters reveal consistency with recent observations while the value of density parameter suggested by Planck 2018 is achieved by power-law scale factor in most of the cases as compared to unified scale factor.

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 Thermodynamics of the viscous f(T,B) gravity in the new agegraphic dark energy model

2020 ◽  
Vol 35 (20) ◽  
pp. 2050166 ◽  
Author(s):  
A. Pourbagher ◽  
Alireza Amani
Keyword(s):  
Dark Energy ◽  
Hubble Parameter ◽  
Dark Energy Model ◽  
Apparent Horizon ◽  
Second Law Of Thermodynamics ◽  
Energy Model ◽  
Accelerated Expansion ◽  
Agegraphic Dark Energy ◽  
New Agegraphic Dark Energy ◽  
The Universe

In this paper, we first obtain the energy density by the approach of the new agegraphic dark energy model, and then the [Formula: see text] gravity model is studied as an alternative to the dark energy in a viscous fluid by flat-FRW background, in which [Formula: see text] and [Formula: see text] are torsion scalar and boundary term. The Friedmann equations will be obtained in the framework of modified teleparallel gravity by tetrad components. We consider that the universe dominates with components such as matter and dark energy by an interacting model. The Hubble parameter is parameterized by the power-law for the scale factor, and then we fit the corresponding Hubble parameter with observational data constraints. The variation of the equation of state (EoS) for dark energy is plotted as a function of the redshift parameter, and the accelerated expansion of the universe is explored. In what follows, the stability of the model is also studied on the base of the sound speed parameter. Finally, the generalized second law of thermodynamics is investigated by entropies of inside and on the boundary of the apparent horizon in thermodynamics equilibrium.

COSMOLOGICAL EVOLUTION OF NEW-AGEGRAPHIC DARK ENERGY MODEL

2008 ◽  
Vol 23 (17n20) ◽  
pp. 1366-1371 ◽  
Author(s):  
H. W. LEE ◽  
K. Y. KIM ◽  
Y. S. MYUNG
Keyword(s):  
Dark Energy ◽  
Differential Equations ◽  
Dark Energy Model ◽  
Critical Value ◽  
Energy Model ◽  
Cosmological Evolution ◽  
Agegraphic Dark Energy ◽  
New Agegraphic Dark Energy

We investigate the cosmological evolution of the new-agegraphic dark energy model which was recently proposed to explain the dark energy-dominated universe. For this purpose, we derived differential equations for density parameters and solved them numerically. We found that there exist a critical value for undetermined parameter of new-agegraphic density to obtain a stable and accessible evolution in the far past. Furthermore, this parameter seems to be fixed as the critical value for consistence.

scholarly journals Reconstruction of the New Agegraphic Polytropic Gas Dark Energy Model in the Flat Friedmann Robertson Walker (FRW) Universe

2021 ◽  
Vol 13 (3) ◽  
pp. 779-784
Author(s):  
P. Das ◽  
K. P. Singh
Keyword(s):  
Dark Energy ◽  
Dark Energy Model ◽  
Scalar Fields ◽  
Energy Model ◽  
Accelerated Expansion ◽  
Frw Universe ◽  
Agegraphic Dark Energy ◽  
New Agegraphic Dark Energy ◽  
Polytropic Gas ◽  
Friedmann Robertson Walker

In this paper, we study the Polytropic Gas Dark Energy model and New Agegraphic Dark Energy model in the flat Friedmann Robertson Walker (FRW) Universe and establish a correspondence between them for the scalar fields. This correspondence allows reconstructing the potential of the Polytropic Gas scalar fields and dynamics of the scalar fields according to the evolutions of the New Agegraphic Dark Energy, which describes the accelerated expansion of the Universe.

scholarly journals Model Independent Diagnostics in Interacting Dark Energy Models

Universe ◽  
2020 ◽  
Vol 6 (4) ◽  
pp. 49
Author(s):  
Ying Jiang ◽  
Zhongxu Han ◽  
Qian Zhang ◽  
Weiqiang Yang ◽  
Yabo Wu ◽  
...  
Keyword(s):  
Dark Energy ◽  
Dark Energy Model ◽  
Cold Dark Matter ◽  
Coupling Parameter ◽  
Gravitational Interaction ◽  
Coupled Model ◽  
State Parameter ◽  
Energy Model ◽  
The State ◽  
Eos Parameter

In this paper, we have explored non-gravitational interaction dark energy model between dark energy and cold dark matter (CDM). The main purpose of this work is to explore the deviations from Λ C D M and to distinguish the evolution trajectory of the interaction dark energy model with different parameters. Six forms of interaction were focused on. We have analyzed the deceleration parameters of the coupled model and explored the theoretical models through s t a t e f i n d e r h i e r a r c h y and the O m diagnostic. We have considered that the Equation of State (EoS) parameter w and parameter ξ take different values on the interaction dark energy model respectively and keep another parameter unchanged. It was found that q ( z ) is the worst of the four diagnoses. O m , S 3 ( 1 ) and S 4 ( 1 ) are good tools to distinguish the interaction dark energy model from Λ C D M . S 3 ( 1 ) is a better diagnostic tool when the state parameter w changes and the coupling parameter ξ is fixed, while S 4 ( 1 ) works better when the coupling parameter ξ changes and the state parameter w is fixed.

Statefinder diagnosis for Tsallis agegraphic dark energy model with ωD − ωD′ pair

2020 ◽  
Vol 35 (06) ◽  
pp. 2050027 ◽  
Author(s):  
Shikha Srivastava ◽  
Vipin Chandra Dubey ◽  
Umesh Kumar Sharma
Keyword(s):  
Dark Energy ◽  
Dark Energy Model ◽  
Energy Model ◽  
Density Parameter ◽  
Statefinder Parameters ◽  
Agegraphic Dark Energy ◽  
New Class ◽  
Nonextensive Entropy ◽  
Age Of The Universe ◽  
The Universe

A new class of dark energy model, known as “Tsallis agegraphic dark energy (TADE),” has been proposed using the holographic principle and Tsallis nonextensive entropy (Mod. Phys. Lett. A, 2019), considering the conformal time as well as the age of the Universe as IR cutoffs in flat Universe. The trajectories for evolution of statefinder parameters in [Formula: see text], [Formula: see text], [Formula: see text] and the [Formula: see text] planes are plotted for the TADE 1 and TADE 2 models for the value of the Tsallis parameter [Formula: see text], and taking the TADE energy density parameter [Formula: see text], according to the Planck 2018 results VI — [Formula: see text]CDM observational data without interaction.

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