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Related papers: Ruling out the Modified Chaplygin Gas Cosmologies

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We derive constraints on the parameter space of the unified model of dark energy and dark matter, the Generalized Chaplygin Gas (GCG), from the amplitudes and positions of the first few peaks and first trough of the cosmic microwave…

Astrophysics · Physics 2008-11-26 T. Barreiro , O. Bertolami , P. Torres

A particular generalization of the Chaplygin inflationary model, using the formalism of Hamilton-Jacobi and elliptic functions, results in a more general non-linear Chaplygin-type equation of state (Chaplygin-Jacobi model). We investigate…

General Relativity and Quantum Cosmology · Physics 2025-03-11 J. A. S. Fortunato , W. S. Hipolito-Ricaldi , N. Videla , J. R. Villanueva

The class of Chaplygin gas models regarded as a candidate of dark energy can be realized by a scalar field, which could drive the variation of the fine structure constant $\alpha$ during the cosmic time. This phenomenon has been observed…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-12 Chao-Jun Feng , Xin-Zhou Li

In this paper, we undertake a unified study of background dynamics and cosmological perturbations in the presence of the Chaplygin gas. This is done by first constraining the background cosmological parameters of different Chaplygin gas…

General Relativity and Quantum Cosmology · Physics 2023-10-12 Shambel Sahlu , Heba Sami , Renier Hough , Maye Elmardi , Anna-Mia Swart , Amare Abebe

The generalized Chaplygin gas cosmology provides a prime example for the class of unified dark matter models, which substitute the two dark components of the standard cosmological LCDM concordance model by a single dark component. The…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-28 Ralf Aurich , Sven Lustig

We formulate a Zel'dovich-like approximation for the Chaplygin gas equation of state P = -A/rho, and sketch how this model unifies dark matter with dark energy in a geometric setting reminiscent of M-theory.

Astrophysics · Physics 2007-05-23 Neven Bilic , Gary B. Tupper , Raoul D. Viollier

On going good number of research works establish Modified Chaplygin Gas as one one of the most favoured candidates of Dark Energy. In our present work, new bound on the parameter space of associated model - parameter has been worked out…

General Physics · Physics 2010-06-09 Balendra Kr. Dev Choudhury , Julie Saikia

The viability of the variable generalised Chaplygin gas (VGCG) model is analysed from the standpoint of its thermodynamical stability criteria with the help of an equation of state, $P = - \frac{B}{\rho^{\alpha}}$, where $B =…

General Relativity and Quantum Cosmology · Physics 2017-02-17 D. Panigrahi , S. Chatterjee

We employ the generalized Chaplygin gas of interacting dark energy to obtain the equation of state for the generalized Chaplygin gas energy density in non-flat universe. By choosing a negative value for $B$ we see that $w_{\rm…

General Relativity and Quantum Cosmology · Physics 2010-10-27 M R Setare

The consequences of taking the generalized Chaplygin gas as the dark energy constituent of the Universe on the gravitational waves are studied and the spectrum obtained from this model, for the flat case, is analyzed. Besides its importance…

General Relativity and Quantum Cosmology · Physics 2009-11-10 J. C. Fabris , S. V. B. Goncalves , M. S. dos Santos

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 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 investigate the cosmological constraints on the Variable Chaplygin gas model from the latest observational data: SCP Union 2.1 compilation dataset of Type Ia supernovae (SNe Ia), Pantheon sample of SNe Ia, Platinum Sample of Gamma Ray…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-11 Ashley Chraya , Yuvraj Muralichandran , Geetanjali Sethi

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

We investigate the background dynamics when dark energy is coupled to dark matter in the universe described by loop quantum cosmology. We consider dark energy of the form modified Chaplygin gas. The dynamical system of equations is solved…

General Physics · Physics 2011-04-04 Mubasher Jamil , Ujjal Debnath

A new model for the universe filled with a generalized Chaplygin fluid is considered which unitarily describes as a single vacuum entity both a quintessence scalar field and a cosmological constant, so unifying the notion of dark energy.…

Astrophysics · Physics 2008-11-26 Pedro F. Gonzalez-Diaz

We study the general properties of a spherically symmetric body described through the generalized Chaplygin equation of state. We conclude that such object, dubbed generalized Chaplygin dark star, should exist within the context of the…

Astrophysics · Physics 2009-11-13 O. Bertolami , J. Paramos

The correspondence of the Gauss-Bonnet (GB) and its modification (MGB) models of dark energy with the standard and generalized Chaplygin gas-scalar field models (SCG and GCG) have been studied in a {\deg}at universe. The exact solution of…

General Relativity and Quantum Cosmology · Physics 2016-11-10 A. Khodam-Mohammadi , E. Karimkhani , A. Alaei

Unified dark matter cosmologies economically combine missing matter and energy in a single fluid. Of these models, the standard Chaplygin gas is theoretically motivated, but faces problems in explaining large scale structure if linear…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-12 Abdelrahman Abdullah , Amr El-Zant , Ali Ellithi

We investigate the linear growth function for the large scale structures of the universe considering modified Chaplygin gas as dark energy. Taking into account observational growth data for a given range of redshift from the Wiggle-Z…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 B. C. Paul , P. Thakur
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