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Related papers: Viscous Modified Cosmic Chaplygin Gas Cosmology

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In this work, we explore the cosmological dynamics of a modified gravity framework based on the function $f(Q,B)=\delta Q^{2}+\beta B$, where $Q$ denotes the nonmetricity scalar and $B$ is the boundary term that relates $Q$ to the Ricci…

General Relativity and Quantum Cosmology · Physics 2025-07-22 Amit Samaddar , S. Surendra Singh

A unified model of dark energy and matter is presented using the modified variable Chaplygin gas for interacting dark energy in a non-flat universe. The two entities interact with each other non-gravitationally which involves a coupling…

Astrophysics · Physics 2008-12-18 Mubasher Jamil , Muneer A. Rashid

We study the nonlinear regime of Unified Dark Energy models, using Generalized Chaplygin Gas cosmologies as a representative example, and introduce a new parameter characterizing the level of small scale clustering in these scenarios. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 P. P. Avelino , K. Bolejko , G. F. Lewis

In this work, we have considered the flat FRW model of the universe in $(n+2)$-dimensions filled with the dark matter (perfect fluid with negligible pressure) and the modified Chaplygin gas (MCG) type dark energy. We present the Hubble…

General Physics · Physics 2015-09-09 Chayan Ranjit , Shuvendu Chakraborty , Ujjal Debnath

A curvature self-interaction of the cosmic gas is shown to mimic a cosmological constant or other forms of dark energy, such as a rolling tachyon condensate or a Chaplygin gas. Any given Hubble rate and deceleration parameter can be traced…

Astrophysics · Physics 2016-08-30 Alexander B. Balakin , Diego Pavon , Dominik J. Schwarz , Winfried Zimdahl

We model the cosmological substratum by a viscous fluid that is supposed to provide a unified description of the dark sector and pressureless baryonic matter. In the homogeneous and isotropic background the \textit{total} energy density of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 W Zimdahl , W S Hipólito-Ricaldi , H E S Velten

We present a holographic dark energy model of the universe considering modified generalized Chaplygin gas (GCG). The modified GCG behaves as an ordinary barotropic fluid in the early epoch when the universe was tiny but behaves subsequently…

General Relativity and Quantum Cosmology · Physics 2007-11-21 B. C. Paul , P. Thakur , A. Saha

This article motivated by the recent articles and results of two authors. Recently, J. Sadeghi and H. Farahani presented a work [1], where they include viscosity and analyze general model, by this way they extended models considered by M.…

General Relativity and Quantum Cosmology · Physics 2016-01-05 J. Sadeghi , M. Khurshudyan , H. Farahani

We consider the evolution of a flat, isotropic and homogeneous Friedmann-Robertson-Walker Universe, filled with a causal bulk viscous cosmological fluid, that can be characterized by an ultra-relativistic equation of state and bulk…

General Relativity and Quantum Cosmology · Physics 2011-10-05 A. Tawfik , M. Wahba , H. Mansour , T. Harko

Unification of dark matter and dark energy as short- and long-range manifestations of a single cosmological substance is possible in models described by the generalized Chaplygin gas equation of state. We show it admits halo-like structures…

General Relativity and Quantum Cosmology · Physics 2017-12-20 T. de Beer , J. W. van Holten

In this work, we have considered the Ricci dark energy model, where the energy density of the universe is proportional to the Ricci scalar curvature, in the dynamic Chern-Simons modified gravity. We show that in this context the evolution…

High Energy Physics - Theory · Physics 2015-06-16 J. G. Silva , A. F. Santos

A bulk viscosity is introduced in the formalism of modified gravity. It is shown that, on the basis of a natural scaling law for the viscosity, a simple solution can be found for quantities such as the Hubble parameter and the energy…

General Relativity and Quantum Cosmology · Physics 2012-11-26 Iver Brevik

The bulk viscosity is introduced to model unified dark matter. The viscous unified model assumes the universe is filled with a single fluid with the bulk viscosity. We review the general framework of the viscous cosmology. The Hubble…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Xu Dou , Xin-He Meng

The effect of bulk viscisity on the evolution of the homogeneous and isotropic cosmological models is considered. Solutions are found, with a barotropic equation of state, and a viscosity coefficient that is proportional to a power of the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Pimentel L O , Diaz-Rivera L M

We analyze the effect of higher order viscosity corrections in a spatially homogeneous and isotropic universe. The viscous effects are modeled by introducing a second-order term to the energy density in the equation of state and on the…

General Relativity and Quantum Cosmology · Physics 2025-09-19 A. G. Cesar , Mario Novello

The Universe is modeled as consisting of pressureless baryonic matter and a bulk viscous fluid which is supposed to represent a unified description of the dark sector. In the homogeneous and isotropic background the \textit{total} energy…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-22 W. Zimdahl , H. E. S. Velten , W. S. Hipólito-Ricaldi

We study the spherical top-hat collapse in Einstein gravity and loop quantum cosmology by taking the non-linear evolution of viscous modified variable chaplygin gas and viscous generalized cosmic chaplygin gas. We calculate the equation of…

General Relativity and Quantum Cosmology · Physics 2016-11-09 Abdul Jawad , Ayesha Iqbal

In this paper we consider a correspondence between the holographic dark energy density and Chaplygin gas energy density in FRW universe. Then we reconstruct the potential and the dynamics of the scalar field which describe the Chaplygin…

High Energy Physics - Theory · Physics 2010-10-27 M R Setare

The nature of the dark components (dark matter and dark energy) that dominate the current cosmic evolution is a completely open question at present. In reality, we do not even know if they really constitute two separated substances. In this…

Astrophysics · Physics 2009-11-10 Abha Dev , Deepak Jain , J. S. Alcaniz

We study the correspondence between field theoretic and holographic dark energy density of the universe with the modified Chaplygin gas (MCG) respectively both in a flat and non-flat FRW universe. We present an equivalent representation of…

High Energy Physics - Theory · Physics 2008-09-23 B. C. Paul , P. Thakur , A. Saha
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