scholarly journals Tsallis, Rényi and Sharma-Mittal Holographic Dark Energy Models in Loop Quantum Cosmology

Symmetry ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 635 ◽  
Author(s):  
Abdul Jawad ◽  
Kazuharu Bamba ◽  
Muhammad Younas ◽  
Saba Qummer ◽  
Shamaila Rani
Keyword(s):  
Dark Energy ◽  
Equation Of State ◽  
Quantum Cosmology ◽  
Cold Dark Matter ◽  
Holographic Dark Energy ◽  
State Parameter ◽  
Loop Quantum Cosmology ◽  
Eos Parameter ◽  
Energy Models ◽  
The Universe

The cosmic expansion phenomenon is being studied through the interaction of newly proposed dark energy models (Tsallis, Rényi and Sharma-Mittal holographic dark energy (HDE) models) with cold dark matter in the framework of loop quantum cosmology. We investigate different cosmic implications such as equation of state parameter, squared sound speed and cosmological plane (ω d - ω d ′ , ω d and ω d ′ represent the equation of state (EoS) parameter and its evolution, respectively). It is found that EoS parameter exhibits quintom like behavior of the universe for all three models of HDE. The squared speed of sound represents the stable behavior of Rényi HDE and Sharma-Mittal HDE at the latter epoch while unstable behavior for Tsallis HDE. Moreover, ω d - ω d ′ plane lies in the thawing region for all three HDE models.

scholarly journals Cosmological aspects of sound speed parameterizations in fractal universe

2019 ◽  
Vol 79 (11) ◽  
Author(s):  
Abdul Jawad ◽  
Sadaf Butt ◽  
Shamaila Rani ◽  
Khadija Asif
Keyword(s):  
Dark Energy ◽  
Equation Of State ◽  
Speed Of Sound ◽  
Cosmological Parameters ◽  
State Parameter ◽  
Graphical Analysis ◽  
Eos Parameter ◽  
Energy Models ◽  
Equation Of State Parameter ◽  
The Universe

AbstractIn the framework of fractal universe, the unified models of dark energy and dark matter are being presented with the background of homogenous and isotropic FLRW geometry. The aspects of fractal cosmology helps in better understanding of the universe in different dimensions. Relationship between the squared speed of the sound and the equation of state parameter is the key feature of these models. We have used constant as well as variable forms of speed of sound and express it as a function of equation of state parameter. By utilizing the four different forms of speed of sound, we construct the energy densities and pressures for these models and then various cosmological parameters like hubble parameter, EoS parameter, deceleration parameter and Om- diagnostic are investigated. Graphical analysis of these parameters show that in most of the cases EoS parameters and trajectories of Om-diagnostic corresponds to the quintessence like nature of the universe and the deceleration parameters represent accelerated and decelerated phase. In the end, we remark that cosmological analysis of these models indicates that these models correspond to different well known dark energy models.

Holographic dark energy models in higher derivative torsion corrected modified teleparallel gravity

2018 ◽  
Vol 15 (04) ◽  
pp. 1850067 ◽  
Author(s):  
Shamaila Rani ◽  
Abdul Jawad
Keyword(s):  
Dark Energy ◽  
Equation Of State ◽  
Holographic Dark Energy ◽  
Teleparallel Gravity ◽  
Eos Parameter ◽  
Phantom Divide ◽  
Energy Models ◽  
Higher Derivative ◽  
Phantom Divide Line ◽  
The Universe

We consider the recently proposed higher derivative torsion corrected modified teleparallel gravity and holographic dark energy (HDE) models. We apply the correspondence scheme to construct models in underlying scenario using various scale factor forms. We investigate the reconstructed functions through equation of state (EoS) parameter. It is demonstrated that the EoS parameter provides quintom-like nature of the Universe in most of the cases, i.e. it drives the Universe from vacuum dark energy era toward phantom era of the Universe by crossing the phantom divide line. We also demonstrate that the consistency with the observational data can be achieved.

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.

Viability of specific reconstructed f(T,𝒯 ) models

2019 ◽  
Vol 34 (30) ◽  
pp. 1950184
Author(s):  
M. Umair Shahzad ◽  
Nadeem Azhar ◽  
Abdul Jawad ◽  
Shamaila Rani
Keyword(s):  
Dark Energy ◽  
Equation Of State ◽  
Dark Energy Model ◽  
State Parameter ◽  
Pilgrim Dark Energy ◽  
Ghost Dark Energy ◽  
Energy Models ◽  
Equation Of State Parameter ◽  
Hubble Horizon ◽  
The Universe

The reconstruction scenario of well-established dark energy models such as pilgrim dark energy model and generalized ghost dark energy with Hubble horizon and [Formula: see text] models is being considered. We have established [Formula: see text] models and analyzed their viability through equation of state parameter and [Formula: see text] (where prime denotes derivative with respect to [Formula: see text]) plane. The equation of state parameter evolutes the universe in three different phases such as quintessence, vacuum and phantom. However, the [Formula: see text] plane also describes the thawing as well as freezing region of the universe. The recent observational data also favor our results.

Pilgrim dark energy models in fractal universe

2016 ◽  
Vol 26 (06) ◽  
pp. 1750049 ◽  
Author(s):  
Abdul Jawad ◽  
Shamaila Rani ◽  
Ines G. Salako ◽  
Faiza Gulshan
Keyword(s):  
Dark Matter ◽  
Dark Energy ◽  
Cold Dark Matter ◽  
Accelerated Expansion ◽  
Freezing And Thawing ◽  
Eos Parameter ◽  
Pilgrim Dark Energy ◽  
Energy Models ◽  
Expansion Behavior ◽  
The Universe

We discuss the cosmological implications of interacting pilgrim dark energy (PDE) models (with Hubble, Granda–Oliveros and generalized ghost cutoffs) with cold dark matter ([Formula: see text]CDM) in fractal cosmology by assuming the flat universe. We observe that the Hubble parameter lies within observational suggested ranges while deceleration parameter represents the accelerated expansion behavior of the universe. The equation of state (EoS) parameter ([Formula: see text]) corresponds to the quintessence region and phantom region for different cases of [Formula: see text]. Further, we can see that [Formula: see text]–[Formula: see text] (where prime indicates the derivative with respect to natural logarithmic of scale factor) plane describes the freezing and thawing regions and also corresponds to [Formula: see text] limit for some cases of [Formula: see text] (PDE parameter). It is also noted that the [Formula: see text]–[Formula: see text] (state-finder parameters) plane corresponds to [Formula: see text] limit and also shows the Chaplygin as well as phantom/quintessence behavior. It is observed that pilgrim dark energy models in fractal cosmology expressed the consistent behavior with recent observational schemes.

scholarly journals Analysis off(R)Theory Corresponding to NADE and NHDE

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
M. Sharif ◽  
M. Zubair
Keyword(s):  
Dark Energy ◽  
Equation Of State ◽  
Deceleration Parameter ◽  
Holographic Dark Energy ◽  
Cosmological Parameters ◽  
State Parameter ◽  
Future Evolution ◽  
Energy Models ◽  
Equation Of State Parameter ◽  
Effective Description

We develop the connection off(R)theory with new agegraphic and holographic dark energy models. The functionf(R)is reconstructed regarding thef(R)theory as an effective description for these dark energy models. We show the future evolution offand conclude that these functions represent distinct pictures of cosmological eras. The cosmological parameters such as equation of state parameter, deceleration parameter, statefinder diagnostic, andw−w′analysis are investigated which assure the evolutionary paradigm off.

scholarly journals Cosmic Evolution of Holographic Dark Energy in f(G,T) Gravity

2019 ◽  
Vol 2019 ◽  
pp. 1-9
Author(s):  
M. Sharif ◽  
Ayesha Ikram
Keyword(s):  
Dark Energy ◽  
Equation Of State ◽  
Phase Plane ◽  
Holographic Dark Energy ◽  
State Parameter ◽  
Momentum Tensor ◽  
Chaplygin Gas ◽  
Cosmic Evolution ◽  
Evolutionary Trajectories ◽  
The Universe

The aim of this paper is to analyze the cosmological evolution of holographic dark energy in f(G,T) gravity (G and T represent the Gauss-Bonnet invariant and trace of the energy-momentum tensor, respectively). We reconstruct f(G,T) model through correspondence scheme using power-law form of the scale factor. The qualitative analysis of the derived model is investigated with the help of evolutionary trajectories of equation of state and deceleration as well as state-finder diagnostic parameters and ωGT-ωGT′ cosmological phase plane. It is found that the equation of state parameter represents phantom epoch of the Universe whereas the deceleration parameter illustrates the accelerated phase. The state-finder plane corresponds to Chaplygin gas model while the freezing region is attained in ωGT-ωGT′ plane.

scholarly journals THERMODYNAMICAL PROPERTIES OF DARK ENERGY IN LOOP QUANTUM COSMOLOGY

2011 ◽  
Vol 20 (02) ◽  
pp. 169-179
Author(s):  
KUI XIAO ◽  
JIAN-YANG ZHU
Keyword(s):  
Dark Energy ◽  
Equation Of State ◽  
Quantum Cosmology ◽  
Thermal Equilibrium ◽  
Apparent Horizon ◽  
State Parameter ◽  
Loop Quantum Cosmology ◽  
Thermodynamical Properties ◽  
The One ◽  
Modified Entropy

Considering an arbitrary, varying equation of state parameter, the thermodynamical properties of dark energy fluid in the semiclassical loop quantum cosmology scenario, where we consider the inverse volume modification, are studied. The equation of state parameters are corrected when we consider the effective behavior. Assuming that the apparent horizon has Hawking temperature, the modified entropy–area relation is obtained, and we find that this relation is different from the one which is obtained by considering the holonomy correction. Considering that the dark energy is in thermal equilibrium with the Hawking radiation of the apparent horizon, we get the expression for the entropy of the dark energy fluid.

Cosmological study in loop quantum cosmology through dark energy model

2017 ◽  
Vol 26 (02) ◽  
pp. 1750007
Author(s):  
Abdul Jawad ◽  
Shamaila Rani ◽  
Ines G. Salako ◽  
Faiza Gulshan
Keyword(s):  
Dark Energy ◽  
Quantum Cosmology ◽  
Cold Dark Matter ◽  
Cosmological Parameters ◽  
Chaplygin Gas ◽  
Accelerated Expansion ◽  
Loop Quantum Cosmology ◽  
Eos Parameter ◽  
Pilgrim Dark Energy ◽  
Expansion Of The Universe

The interacting generalized ghost version of pilgrim dark energy (GGPDE) is discussed in the framework of loop quantum cosmology (LQC). We analyze the behavior of cosmological parameters (Hubble, equation of state (EoS), deceleration) and cosmological planes ([Formula: see text] and [Formula: see text]-[Formula: see text]) in the present scenario ([Formula: see text] represents the EoS parameter and [Formula: see text] indicates the evolution of the EoS parameter, [Formula: see text],[Formula: see text] are statefinder parameters). It is observed that the deceleration parameter corresponds to the accelerated expansion of the universe. The EoS parameter lies in vacuum and phantom regions for all cases of [Formula: see text] (pilgrim dark energy (PDE) parameter). The [Formula: see text] plane lies in thawing region for all cases of [Formula: see text]. The [Formula: see text] plane corresponds to [Formula: see text] cold dark matter (CDM) and Chaplygin gas model. We have also mentioned the constraints on calculated cosmological parameters and found that all the trajectories of cosmological parameters and planes show the consistence behavior with the observational schemes.

Study of Tsallis, Rényi and Sharma–Mittal holographic dark energies for entropy corrected modified field equations in Hořava–Lifshitz gravity

2020 ◽  
Vol 17 (11) ◽  
pp. 2050170
Author(s):  
Sayani Maity ◽  
Ujjal Debnath
Keyword(s):  
Dark Energy ◽  
Equation Of State ◽  
Speed Of Sound ◽  
Cold Dark Matter ◽  
State Parameter ◽  
Accelerated Expansion ◽  
Field Equations ◽  
Frw Universe ◽  
Equation Of State Parameter ◽  
The Universe

The purpose of this work is to study the Tsallis, Rényi and Sharma–Mittal holographic dark energy models in order to evaluate the accelerated expansion of the Universe. In this regard, we consider the modified field equations for logarithmic and power law versions of entropy corrected models in FRW Universe filled with interacting dark energy and cold dark matter within the framework of Hořava–Lifshitz gravity. Employing the Nojiri and Odintsov (NO) cut-off as infrared cutoff, we explore the nature of the different cosmological quantities like the equation of state parameter, squared speed of sound and [Formula: see text]–[Formula: see text] cosmological plane during the cosmic evolution. The equation of state parameter shows the different stages of the evolution of the Universe for the considered models. By analyzing the cosmological plane [Formula: see text]–[Formula: see text], we obtain the freezing region for these models. Also, due to the study of squared speed of sound, we show the classically stable behavior of the considered models.

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