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Related papers: Density Evolution in the New Modified Chaplygin Ga…

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In this work we set observational constraints of the Superfluid Chaplygin gas model, which gives a unified description of the dark sector of the Universe as a Bose-Einstein condensate (BEC) that behaves as dark energy (DE) while it is in…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-12 Ruth Lazkoz , Ariadna Montiel , Vincenzo Salzano

The Chaplygin gas (CG) and the generalized Chaplygin gas (GCG) models, proposed as candidates of the unified dark matter-dark energy (UDME), are tested with the look-back time (LT) redshift data. We find that the LT data only give a very…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-11 Zhengxiang Li , Puxun Wu , Hongwei Yu

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 Einstein-Aether gravity. Dark energy in the form of Modified Chaplygin gas is…

General Physics · Physics 2014-08-21 Chayan Ranjit , Prabir Rudra , Sujata Kundu

We analyse three cosmological scenarios with interaction in the dark sector, which are particular cases of a general expression for the energy flux from vacuum to matter. In the first case the interaction leads to a transition from an…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-31 L. P. Chimento , S. Carneiro

A cosmological model with a new variant of Chaplygin gas obeying an equation of state(EoS), $P = A\rho - \frac{B}{\rho^{\alpha}}$ where $B= B_{0}a^{n}$ is investigated in the context of its thermodynamical behaviour. Here $B_{0}$ and $n$…

General Relativity and Quantum Cosmology · Physics 2017-02-07 D. Panigrahi , S. Chatterjee

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

In the paper, we have presented a higher-dimensional cosmological model with a generalized Chaplygin-type gas to explain the recent acceleration of the universe. Dimensional reduction is feasible in this model, and our solutions are…

General Relativity and Quantum Cosmology · Physics 2025-07-01 D. Panigrahi , B. C. Paul , S. Chatterjee

We discuss the importance of including baryons in analyses of unified dark matter scenarios, focusing on toy models involving a generalized Chaplygin gas. We determine observational constraints on this unified dark matter scenario coming…

Astrophysics · Physics 2009-11-07 L. M. G. Beca , P. P. Avelino , J. P. M. de Carvalho , C. J. A. P. Martins

In this work we study to which extent the knowledge of spatial topology may place constraints on the parameters of the generalized Chaplygin gas (GCG) model for unification of dark energy and dark matter. By using both the Poincar\'e…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. C. Bento , O. Bertolami , M. J. Rebouças , P. T. Silva

We clarify thermodynamics of the Chaplygin gas by introducing the integrability condition. All thermal quantities are derived as functions of either volume or temperature. Importantly, we find a new general equation of state, describing the…

General Relativity and Quantum Cosmology · Physics 2011-09-12 Yun Soo Myung

In the framework of spatially averaged inhomogeneous cosmologies in classical general relativity, effective Einstein equations govern the dynamics of averaged scalar variables in a scale--dependent way. A particular cosmology may be…

General Relativity and Quantum Cosmology · Physics 2010-08-23 Xavier Roy , Thomas Buchert

Within the framework of Unimodular Gravity, we consider non-gravitational interactions between dark matter and dark energy. Particularly, we describe such interactions in the dark sector by considering diffusion models that couple the cold…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-31 Francisco X. Linares Cedeño , Ulises Nucamendi

The models that unify dark matter and dark energy based upon the Chaplygin gas fail owing to the suppression of structure formation by the adiabatic speed of sound. Including string theory effects, in particular the Kalb-Ramond field, we…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Neven Bilic , Gary B. Tupper , Raoul D. Viollier

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

While the origin and composition of dark matter and dark energy remains unknown, it is possible that they might represent two manifestations of a single entity, as occurring in unified dark sector models. On the other hand, advances in our…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-02 Weiqiang Yang , Supriya Pan , Sunny Vagnozzi , Eleonora Di Valentino , David F. Mota , Salvatore Capozziello

If the spatial section of the universe is multiply connected, repeated images or patterns are expected to be detected observationally. However, due to the finite distance to the last scattering surface, such pattern repetitions could be…

Astrophysics · Physics 2008-11-26 B. Mota , M. Makler , M. J. Reboucas

In this Letter, a modified Chaplygin gas (MCG) model of unifying dark energy and dark matter with the exotic equation of state $p_{MCG}=B\rho_{MCG} -\frac A{\rho_{MCG}^\alpha}$ is constrained from recently observed data: the 182 Gold SNe…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-07 Jianbo Lu , Lixin Xu , Jiechao Li , Baorong Chang , Yuanxing Gui , Hongya Liu

The generalized Chaplygin gas (GCG) model explains the recent accelerated expansion of the Universe via an exotic background fluid whose equation of state is given by p=-A/\rho^\alpha, where A is a positive constant and 0<\alpha\le 1. The…

Astrophysics · Physics 2015-06-24 M. C. Bento , O. Bertolami , A. A. Sen

We investigate the possibility of constraining Chaplygin dark energy models with current Integrated Sachs Wolfe effect data. In the case of a flat universe we found that generalized Chaplygin gas models must have an energy density such that…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Tommaso Giannantonio , Alessandro Melchiorri

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