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Unified cosmological models have received a lot of attention in astrophysics community for explaining both the dark matter and dark energy evolution. The Chaplygin cosmologies, a well known name in this group have been investigated matched…

General Relativity and Quantum Cosmology · Physics 2019-10-09 Weiqiang Yang , Supriya Pan , Andronikos Paliathanasis , Subir Ghosh , Yabo Wu

Unified dark matter models are appealing in that they describe the dark sector in terms of a single component. They however face problems when attempting to account for structure formation: in the linear regime, density fluctuations can…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-16 Amr El-Zant

We model the cosmic medium as the mixture of a generalized Chaplygin gas and a pressureless matter component. Within a neo-Newtonian approach (in which, different from standard Newtonian cosmology, the pressure enters the homogeneous and…

Astrophysics · Physics 2010-04-15 J. C. Fabris , S. V. B. Goncalves , H. E. S. Velten , W. Zimdahl

The generalized Chaplygin gas (GCG) model allows for an unified description of the recent accelerated expansion of the Universe and the evolution of energy density perturbations. This dark energy - dark matter unification is achieved…

General Relativity and Quantum Cosmology · Physics 2014-11-17 M. C. Bento , O. Bertolami , A. A. Sen

The recent observational evidence for the current cosmic acceleration have stimulated renewed interest in alternative cosmologies, such as scenarios with interaction in the dark sector (dark matter and dark energy). In general, such models…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-22 R. S. Goncalves , J. S. Alcaniz , A. Dev , D. Jain

The problem of reproducing dark energy effects is reviewed here with particular interest devoted to cosmography. We summarize some of the most relevant cosmological models, based on the assumption that the corresponding barotropic equations…

General Relativity and Quantum Cosmology · Physics 2013-12-09 Salvatore Capozziello , Mariafelicia De Laurentis , Orlando Luongo , Alan Cosimo Ruggeri

We revisit a cosmological model where dark matter (DM) and dark energy (DE) follow barotropic equations of state, allowing deviations from the standard $\Lambda$CDM framework (i.e. $w_{dm} \neq 0$, $w_{de} \neq -1$), considering both flat…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-24 Dorian Araya , Cristian Castillo , Genly Leon , Juan Magaña , Angie Barr Domínguez , Miguel A. García-Aspeitia

In this work we investigate the background dynamics when dark energy is coupled to dark matter with a suitable interaction in the universe described by Loop quantum cosmology. Dark energy in the form of Generalised Cosmic Chaplygin gas is…

General Physics · Physics 2015-06-04 Ratul Chowdhury , Prabir Rudra

This study investigates the potential of a cosmological model termed $\Lambda w$DM, in which a cosmological constant play the role of dark energy and dark matter is barotropic and has a constant equation of state parameter ($w_{\rm dm}$),…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-02 Yan-Hong Yao , Jian-Qi Liu

While cold dark matter is widely supported by a range of cosmological observations, it encounters several difficulties at smaller scales. These issues have prompted the investigation of various alternative dark matter candidates, leaving…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-23 Jian-Qi Liu , Yan-Hong Yao , Yan Su , Jia-Wei Wu

In this paper, after reconstructing the redshift evolution of the Hubble function by adopting Gaussian process techniques, we estimate the best-fit parameters for some flat Friedmann cosmological models based on a Modified Chaplygin Gas…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-28 Muhsin Aljaf , Daniele Gregoris , Martiros Khurshudyan

We present improved constraints on an interacting vacuum model using updated astronomical observations including the first data release from Planck. We consider a model with one dimensionless parameter, $\alpha$, describing the interaction…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-09 Yuting Wang , David Wands , Gong-Bo Zhao , Lixin Xu

The hypothesis that dark matter and dark energy are unified through the Chaplygin gas is reexamined. Using generalizations of the spherical model which incorporate effects of the acoustic horizon we show that an initially perturbative…

Astrophysics · Physics 2008-11-26 Neven Bilic , Robert J. Lindebaum , Gary B. Tupper , Raoul D. Viollier

Unified Dark Matter models describe Dark Matter and Dark Energy as a single entity which is, in the simplest case, embodied in a perfect barotropic fluid. It is a well-established fact that small adiabatic perturbations of Unified Dark…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-28 Oliver F. Piattella

We investigate a model of interacting dark matter and dark energy given by a modified holographic Ricci cutoff in a spatially flat Friedmann-Robertson-Walker (FRW) space-time. We consider a nonlinear interaction consisting of a significant…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-30 Luis P. Chimento , Martín G. Richarte

In this paper, the viscous cosmological dynamics are studied in the presence of dark matter Bose-Einstein Condensation (BEC) by curved-FRW background. For this purpose, we use the BEC regime rather than the normal dark matter (the cold dark…

General Relativity and Quantum Cosmology · Physics 2021-11-24 E. Mahichi , Alireza Amani , M. A. Ramzanpour

We study a generalized version of Chaplygin gas as unified model of dark matter and dark energy. Using realistic theoretical models and the currently available observational data from the age of the universe, the expansion history based on…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-15 Chan-Gyung Park , Jai-chan Hwang , Jaehong Park , Hyerim Noh

A model of unification of dark matter and dark energy based on the modeling of the speed of sound as a function of the parameter of the equation of state is introduced. It is found that the model in which the speed of sound depends on the…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-04 Neven Caplar , Hrvoje Stefancic

In this work we explore the background dynamics when dark energy is coupled to dark matter with a suitable interaction in the universe described by brane cosmology. Here DGP and the RSII brane models have been considered separately. Dark…

General Physics · Physics 2015-06-05 Prabir Rudra

We use the Markov Chain Monte Carlo method to investigate a global constraints on the generalized Chaplygin gas (GCG) model as the unification of dark matter and dark energy from the latest observational data: the Constitution dataset of…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-07 Lixin Xu , Jianbo Lu