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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

In this article we will consider several phenomenological models for the Universe with varying $G$ and $\Lambda(t)$, where $G$ is the gravitational "constant" and $\Lambda(t)$ is a varying cosmological "constant". Two-component fluid model…

General Relativity and Quantum Cosmology · Physics 2015-09-16 M. Khurshudyan

In this paper, we consider an unusual connection between different fluids. Having established a research goal we would like to consider a toy model of the Universe and investigate its behavior, especially for later time evolution for well…

General Physics · Physics 2015-07-28 M. Khurshudyan , B. Pourhassan

In this paper we consider several phenomenological models of variable $\Lambda$. Model of a flat Universe with variable $\Lambda$ and $G$ is accepted. It is well known, that varying $G$ and $\Lambda$ gives rise to modified field equations…

General Relativity and Quantum Cosmology · Physics 2013-12-17 J. Sadeghi , M. Khurshudyan , A. Movsisyan , H. Farahani

We are interested by the study of several toy models of the Universe in presence of interacting quintessence DE models. Models are considered in the cosmology with an Effective varying $\Lambda$-Term in Lyra Manifold. The motivation of the…

General Relativity and Quantum Cosmology · Physics 2015-09-16 Martiros Khurshudyan

In this paper, we consider three different models of dark energy in higher dimensional space-time and discuss about some cosmological parameters numerically. The first model is a single component universe including viscous varying modified…

General Relativity and Quantum Cosmology · Physics 2014-06-13 M. Khurshudyan , J. Sadeghi , M. Hakobyan , H. Farahani , R. Myrzakulov

In this paper, we attempt to explore the possibility of a obtaining a viable emergent universe scenario supported by a type of fluid known as the extended Chaplygin gas, which extends a modification to the equation of state of the well…

General Relativity and Quantum Cosmology · Physics 2025-08-13 Rikpratik Sengupta , Anirban Chanda , B C Paul , M Kalam

In this paper we have considered the Universe to be filled with Modified Gas and the Cosmological Constant $\Lambda$ to be time-dependent with or without the Gravitational Constant $G$ to be time-dependent. We have considered various…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Writambhara Chakraborty , Ujjal Debnath

In this paper, we study two different models of dark energy based on Chaplygin gas equation of state. The first model is the variable modified Chaplygin gas while the second one is the extended Chaplygin gas. Both models are considered in…

General Relativity and Quantum Cosmology · Physics 2015-02-10 E. O. Kahya , M. Khurshudyan , B. Pourhassan , R. Myrzakulov , A. Pasqua

Motivated by recent developments in Cosmology we would like to consider an extension of the Ghost DE which we will call as varying Ghost DE. Ghost DE like other models was introduced recently as a possible way to explain accelerated…

General Relativity and Quantum Cosmology · Physics 2015-07-28 Martiros Khurshudyan , Amalya Khurshudyan

In this paper, we consider Universe filled with two-component fluid. We study two different models. In the first model we assume barotropic fluid with the linear equation of state as the first component of total fluid. In the second model…

General Relativity and Quantum Cosmology · Physics 2014-05-01 M. Khurshudyan , B. Pourhassan , E. O. Kahya

In this letter we consider two different models of our present universe. We choose the models which are consisting different sets of two seperate fluids. The first one of each set tries to justify the late time acceleration and the second…

General Physics · Physics 2019-03-27 Promila Biswas , Ritabrata Biswas

Addressing the late-time accelerated expansion of the universe, known as the "dark energy problem", remains a central challenge in cosmology. While the cosmological constant is the standard explanation, alternative models such as…

General Relativity and Quantum Cosmology · Physics 2025-10-27 Gilberto Aguilar-Pérez , Miguel Cruz , Mohsen Fathi , Daniel de Jesús García-Castro , J. R. Villanueva

The subject of our interest is an extended Chaplygin gas cosmology. In Literature a variety of cosmological models exist studying the behavior of the universe in the presence of the Chaplygin gas. From its initial form Chaplygin gas evolved…

General Relativity and Quantum Cosmology · Physics 2014-10-23 Martiros Khurshudyan

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

In this work, we have considered modified Chaplygin gas with variable G and $\Lambda$. The trivial solution describes decelerating phase to accelerating phase of the universe. The non-static with constant equation of state describes the…

General Physics · Physics 2015-03-18 Ujjal Debnath

The standard model of cosmology is investigated using time dependent cosmological constant $\Lambda$ and Newton's gravitational constant $G$. The total energy content is described by the modified Chaplygin gas equation of state. It is found…

General Relativity and Quantum Cosmology · Physics 2009-03-12 Mubasher Jamil , Farook Rahaman , Mehedi Kalam

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

This thesis concentrates on the accelerated expansion of the Universe recently explored by measurements of redshift and luminosity-distance relations of type Ia Supernovae. We have considered a model of the universe filled with modified…

General Relativity and Quantum Cosmology · Physics 2011-05-06 Writambhara Chakraborty

In this paper, we have considered a model of modified Chaplygin gas in VSL theory with variable gravitational constant $G$. We have shown that the evolution of the universe starts from radiation era to phantom model. The whole evolution of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Anup Kumar Singha , Ujjal Debnath
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