Two-fluid scenario for dark energy models in an FRW universe-revisited

Within the framework of FRW cosmology, we study the QCD modified ghost scalar field models of dark energy (DE) in the presence of both interaction and viscosity. For a spatially nonflat FRW universe containing modified ghost dark energy (MGDE) and dark matter (DM), we obtain the equation of state of MGDE, the deceleration parameter as well as a differential equation governing the MGDE density parameter. We also investigate the growth of structure formation for our model in a linear perturbation regime. Furthermore, we reconstruct both the dynamics and potentials of the quintessence, tachyon, K-essence and dilaton scalar field DE models according to the evolution of the MGDE density.

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Various dark energy models for variables G and Λ in f(R, T) modified theory

Modern Physics Letters A ◽

10.1142/s0217732319500986 ◽

2019 ◽

Vol 34 (13) ◽

pp. 1950098 ◽

Cited By ~ 6

Author(s):

Can Aktaş

Keyword(s):

Dark Energy ◽

Energy Momentum Tensor ◽

Momentum Tensor ◽

Tachyon Field ◽

Field Equations ◽

Frw Universe ◽

Linearly Varying Deceleration Parameter ◽

Energy Models ◽

Modified Theory ◽

Friedmann Robertson Walker

In this paper, we have researched tachyon field, k-essence and quintessence dark energy (DE) models for Friedmann–Robertson–Walker (FRW) universe with varying G and [Formula: see text] in f(R, T) gravitation theory. The theory of f(R, T) is proposed by Harko et al. [Phys. Rev. D 84, 024020, 2011]. In this theory, R is the Ricci scalar and T is the trace of energy–momentum tensor. For the solutions of field equations, we have used linearly varying deceleration parameter (LVDP), the equation of state (EoS) and the ratio between [Formula: see text] and Hubble parameter. Also, we have discussed some physical behavior of the models with various graphics.

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Two-Fluid Dark Energy Models in Bianchi Type-III Universe with Variable Deceleration Parameter

International Journal of Theoretical Physics ◽

10.1007/s10773-013-1566-7 ◽

2013 ◽

Vol 52 (8) ◽

pp. 2735-2752 ◽

Cited By ~ 15

Author(s):

Hassan Amirhashchi ◽

Anirudh Pradhan ◽

Rekha Jaiswal

Keyword(s):

Dark Energy ◽

Deceleration Parameter ◽

Bianchi Type ◽

Variable Deceleration Parameter ◽

Type Iii ◽

Energy Models ◽

Two Fluid

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Generalized entropies and corresponding holographic dark energy models

The European Physical Journal C ◽

10.1140/epjc/s10052-020-8307-x ◽

2020 ◽

Vol 80 (8) ◽

Cited By ~ 3

Author(s):

H. Moradpour ◽

A. H. Ziaie ◽

M. Kord Zangeneh

Keyword(s):

Black Holes ◽

Dark Energy ◽

Holographic Dark Energy ◽

Apparent Horizon ◽

Tsallis Entropy ◽

Accelerating Universe ◽

Frw Universe ◽

Energy Models ◽

Generalized Entropies ◽

The Universe

Abstract Using Tsallis statistics and its relation with Boltzmann entropy, the Tsallis entropy content of black holes is achieved, a result in full agreement with a recent study (Mejrhit and Ennadifi in Phys Lett B 794:24, 2019). In addition, employing Kaniadakis statistics and its relation with that of Tsallis, the Kaniadakis entropy of black holes is obtained. The Sharma-Mittal and Rényi entropy contents of black holes are also addressed by employing their relations with Tsallis entropy. Thereinafter, relying on the holographic dark energy hypothesis and the obtained entropies, two new holographic dark energy models are introduced and their implications on the dynamics of a flat FRW universe are studied when there is also a pressureless fluid in background. In our setup, the apparent horizon is considered as the IR cutoff, and there is not any mutual interaction between the cosmic fluids. The results indicate that the obtained cosmological models have (i) notable powers to describe the cosmic evolution from the matter-dominated era to the current accelerating universe, and (ii) suitable predictions for the universe age.

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