scholarly journals Diagnosing Tsallis holographic dark energy models with interactions

2019 ◽  
Vol 35 (08) ◽  
pp. 2050044 ◽  
Author(s):  
Nan Zhang ◽  
Ya-Bo Wu ◽  
Jia-Nan Chi ◽  
Zhe Yu ◽  
Dong-Fang Xu
Keyword(s):  
Dark Energy ◽  
Holographic Dark Energy ◽  
Diagnostic Methods ◽  
Model Parameters ◽  
Diagnostic Parameters ◽  
Om Diagnostic ◽  
Energy Models ◽  
Evolutionary Trajectories

It has been found that the geometrical diagnostic methods can break the degeneracy for dark energy models. In this paper, we investigate the Om diagnostic, the statefinder hierarchy [Formula: see text] and the composite null diagnostic [Formula: see text] for the Tsallis holographic dark energy models with interactions. We find that model parameters and the forms of interaction will influence the values of diagnostic parameters or the trends of the evolutionary trajectories for each model. Moreover, the statefinder hierarchy [Formula: see text] together with [Formula: see text] could give good diagnostic results. Furthermore, we also obtain some issues of cosmological structure by means of the composite null diagnostic.

Diagnosing Tsallis holographic dark energy models with statefinder and ω − ω′ pair

2019 ◽  
Vol 34 (13) ◽  
pp. 1950101 ◽  
Author(s):  
Umesh Kumar Sharma ◽  
Anirudh Pradhan
Keyword(s):  
Dark Energy ◽  
Energy Density ◽  
Holographic Dark Energy ◽  
Tsallis Entropy ◽  
Observation Data ◽  
Energy Models ◽  
Evolutionary Trajectories

A useful method, known as statefinder diagnostic, which may differentiate one dark energy (DE) model from others is applied in this work to a holographic dark energy (HDE) model from Tsallis entropy, called the Tsallis holographic dark energy (THDE) model. The evolutionary trajectories of this model are plotted in the statefinder parameter — planes and [Formula: see text] plane, and it is observed that the parameter [Formula: see text] of this model plays a magnificent role from the statefinder and [Formula: see text] plane viewpoints. Eventually, the evolutionary trajectories are plotted considering two different values of THDE energy density ([Formula: see text]), [Formula: see text], in the light of Planck 2018 results VI base-LCDM cosmology and [Formula: see text], in the light of SNe + BAO + OHD + CMB observation data.

Comparing entropy inspired holographic dark energy models through statefinder hierarchy and growth rate of perturbations

2021 ◽  
Vol 18 (12) ◽  
Author(s):  
Mukesh Kumar ◽  
Vipin Chandra Dubey ◽  
Umesh Kumar Sharma
Keyword(s):  
Growth Rate ◽  
Dark Energy ◽  
Holographic Dark Energy ◽  
Growth Parameter ◽  
Early Time ◽  
Diagnostic Tools ◽  
Late Time ◽  
Energy Models ◽  
Evolutionary Trajectories ◽  
Different Characteristics

In this paper, we have investigated some recently proposed entropy-based versions of various HDE models, namely, the TADE, THDE, RHDE and SMHDE for different values of model parameter [Formula: see text] with the help of two diagnostic tools, in the context of a flat Friedmann–Lema[Formula: see text]tre–Robertson–Walker Universe. The statefinder hierarchy is the first diagnostic tool, by which we examine these DE models. The evolution of statefinder hierarchy parameters [Formula: see text], [Formula: see text] [Formula: see text], [Formula: see text] has been investigated by plotting against redshift [Formula: see text]. The evolutionary trajectories of all the DE models approach the [Formula: see text]CDM model, except the TADE model for some values of [Formula: see text] at late time, are well discriminated with the [Formula: see text]CDM model at early time. To get more clear discrimination among the DE models at late time, we have used the CND, i.e. [Formula: see text][Formula: see text], where [Formula: see text] indicates the fractional growth parameter. The evolutionary trajectories of [Formula: see text] and [Formula: see text] show different characteristics and the departure from [Formula: see text]CDM could be well evaluated.

Analysis on modified Chaplygin gas as dark energy model

2015 ◽  
Vol 30 (01) ◽  
pp. 1550005 ◽  
Author(s):  
Ya-Bo Wu ◽  
Cheng-Yuan Zhang ◽  
Jian-Bo Lu ◽  
Jun-Wang Lu ◽  
Xue Zhang ◽  
...  
Keyword(s):  
Dark Energy ◽  
Scalar Field ◽  
Chaplygin Gas ◽  
Model Parameters ◽  
Modified Chaplygin Gas ◽  
Related Data ◽  
Om Diagnostic ◽  
Interaction Terms ◽  
Special Cases ◽  
Evolutionary Trajectories

In this paper, we will continue to study the modified Chaplygin gas (MCG) based on Ref. 25. Concretely, we not only discuss both the change rates of the energy densities and the Hubble parameter H(z) as a function of the model parameters, which is compared and consistent with the related data in Ref. 27, but also perform the Om diagnostic in order to geometrically differentiate the MCG model from the ΛCDM, GCG and CG models. Moreover, we plot the evolutionary trajectories of MCG model with different interaction terms in Om planes, and find that the coupling intensity b2 plays an important role in the MCG model. Furthermore, we also reconstruct the potential of MCG scalar field as well as the dynamics of the scalar field according to the evolution of the MCG dark energy. It is worth stressing that the results given by us can include the ones without interaction as the special cases.

scholarly journals STATEFINDER DIAGNOSTIC FOR HOLOGRAPHIC DARK ENERGY MODEL

2005 ◽  
Vol 14 (09) ◽  
pp. 1597-1606 ◽  
Author(s):  
XIN ZHANG
Keyword(s):  
Dark Energy ◽  
Observational Data ◽  
High Precision ◽  
Significant Role ◽  
Dark Energy Model ◽  
Holographic Dark Energy ◽  
Energy Model ◽  
Holographic Dark Energy Model ◽  
Energy Models ◽  
Evolutionary Trajectories

In this paper, we study the holographic dark energy model proposed by Li from the statefinder viewpoint. We plot the evolutionary trajectories of the model with c = 1 in the statefinder parameter-planes. The statefinder diagrams characterize the properties of the holographic dark energy and show the discrimination between this scenario and other dark energy models. We also perform a statefinder diagnostic to the holographic dark energy model in cases of different c which given by three fits to observational data. The result indicates that from the statefinder viewpoint c plays a significant role in this model and should thus be determined seriously by future high precision experiments.

scholarly journals Quintessence and Holographic Dark Energy infTGravity

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
M. Zubair
Keyword(s):  
Dark Energy ◽  
Dark Energy Model ◽  
Holographic Dark Energy ◽  
State Parameter ◽  
Energy Model ◽  
Cosmic Acceleration ◽  
Model Parameters ◽  
Efficient Tool ◽  
Future Evolution ◽  
Energy Models

We regardfTtheory as an efficient tool to explain the current cosmic acceleration and associate its evolution with the known dark energy models. The numerical scheme is applied to reconstructfTtheory from dark energy model with constant equation of state parameter and holographic dark energy model. We set the model parametersωϑandcas describing the different evolution eras and show the distinctive behavior of each case realized infTtheory. We also present the future evolution of reconstructedfTand find that it is consistent with the recent observations.

scholarly journals Physical Acceptability of the Renyi, Tsallis and Sharma-Mittal Holographic Dark Energy Models in the f(T,B) Gravity under Hubble’s Cutoff

Universe ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 67
Author(s):  
Salim Harun Shekh ◽  
Pedro H. R. S. Moraes ◽  
Pradyumn Kumar Sahoo
Keyword(s):  
Dark Energy ◽  
Holographic Dark Energy ◽  
Cosmological Parameters ◽  
Field Equations ◽  
Eos Parameter ◽  
Two Fluids ◽  
Gravitational Field Equations ◽  
Energy Models ◽  
Different Types ◽  
The Universe

In the present article, we investigate the physical acceptability of the spatially homogeneous and isotropic Friedmann–Lemâitre–Robertson–Walker line element filled with two fluids, with the first being pressureless matter and the second being different types of holographic dark energy. This geometric and material content is considered within the gravitational field equations of the f(T,B) (where T is the torsion scalar and the B is the boundary term) gravity in Hubble’s cut-off. The cosmological parameters, such as the Equation of State (EoS) parameter, during the cosmic evolution, are calculated. The models are stable throughout the universe expansion. The region in which the model is presented is dependent on the real parameter δ of holographic dark energies. For all δ≥4.5, the models vary from ΛCDM era to the quintessence era.

scholarly journals Bianchi type-III Tsallis holographic dark energy model in Saez–Ballester theory of gravitation

2020 ◽  
Vol 80 (12) ◽  
Author(s):  
M. Vijaya Santhi ◽  
Y. Sobhanbabu
Keyword(s):  
Dark Energy ◽  
Bianchi Type ◽  
Graphical Representation ◽  
Holographic Dark Energy ◽  
Cosmological Parameters ◽  
State Parameter ◽  
Field Equations ◽  
Om Diagnostic ◽  
Hubble Radius ◽  
Theory Of Gravitation

AbstractIn this paper, we have investigated Tsallis holographic dark energy (infrared cutoff is the Hubble radius) in homogeneous and anisotropic Bianchi type-III Universe within the framework of Saez–Ballester scalar–tensor theory of gravitation. We have constructed non-interaction and interaction dark energy models by solving the Saez–Ballester field equations. To solve the field equations, we assume a relationship between the metric potentials of the model. We developed the various cosmological parameters (namely deceleration parameter q, equation of state parameter $$\omega _t$$ ω t , squared sound speed $$v_s^2$$ v s 2 , om-diagnostic parameter Om(z) and scalar field $$\phi $$ ϕ ) and well-known cosmological planes (namely $$\omega _t-\omega _t^{'}$$ ω t - ω t ′ plane, where $$'$$ ′ denotes derivative with respect to ln(a) and statefinders ($$r-s$$ r - s ) plane) and analyzed their behavior through graphical representation for our both the models. It is also, quite interesting to mention here that the obtained results are coincide with the modern observational data.

scholarly journals SUPERNOVA Ia AND GALAXY CLUSTER GAS MASS FRACTION CONSTRAINTS ON DARK ENERGY

2006 ◽  
Vol 21 (29) ◽  
pp. 2197-2204 ◽  
Author(s):  
KYLE M. WILSON ◽  
GANG CHEN ◽  
BHARAT RATRA
Keyword(s):  
Dark Energy ◽  
Energy Density ◽  
Cosmological Constant ◽  
Mass Fraction ◽  
Galaxy Cluster ◽  
Apparent Magnitude ◽  
Model Parameters ◽  
Dark Energy Density ◽  
Energy Models ◽  
Fraction Versus

We use the Riess et al. (2004)1 supernova Ia apparent magnitude versus redshift data and the Allen et al. (2004)2 galaxy cluster gas mass fraction versus redshift data to constrain dark energy models. These data provide complementary constraints that when combined together significantly restrict model parameters and favor slowly-evolving dark energy density models, close to the Einstein cosmological constant limit of dark energy.

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