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We show that a generalised phantom Chaplygin gas can present a future singularity in a finite future cosmic time. Unlike the big rip singularity, this singularity happens for a finite scale factor, but like the big rip singularity, it would…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Mariam Bouhmadi-Lopez , Pedro F. Gonzalez-Diaz , Prado Martin-Moruno

Unified generalized Chaplygin gas models assuming an interaction between dark energy and dark matter fluids have been previously proposed. Following these ideas, we consider a particular relation between dark densities, which allows the…

High Energy Physics - Theory · Physics 2008-11-26 H. Garcia-Compean , G. Garcia-Jimenez , O. Obregon , C. Ramirez

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

Although it has been believed that the models with generalised Chaplygin gas do not contain singularities, in a previous work we have studied how a big freeze could take place in some kinds of phantom generalised Chaplygin gas. In the…

General Relativity and Quantum Cosmology · Physics 2009-02-11 Mariam Bouhmadi-Lopez , Pedro F. Gonzalez-Diaz , Prado Martin-Moruno

We study the possible types of future singularities in the isotropic homogeneous cosmological models for the arbitrary equation of state of the contents of the Universe. We obtain all known types of these singularities as well as two new…

General Relativity and Quantum Cosmology · Physics 2016-09-27 S. L. Parnovsky

Hybrid Chaplygin gas model is put forward, in which the gases play the role of dark energy. For this model the coincidence problem is greatly alleviated. The effective equation of state of the dark energy may cross the phantom divide…

Astrophysics · Physics 2015-05-13 Hongsheng Zhang , Zong-Hong Zhu , Lihua Yang

Cosmologists have long wondered whether the Universe will eventually re-collapse and end with a Big Crunch, or expand forever, becoming increasingly cold and empty. Recent evidence for a flat Universe, possibly with a cosmological constant…

Astrophysics · Physics 2009-11-07 Robert R. Caldwell , Marc Kamionkowski , Nevin N. Weinberg

Phantom dark energy models, with w < -1, are characterized by a future singularity and therefore a finite lifetime for the universe. Because the future singularity is triggered by the onset of dark-energy domination, the universe spends a…

Astrophysics · Physics 2009-11-10 Robert J. Scherrer

Singularities in any physical theory are either remarkable indicators of the unknown underlying fundamental theory, or indicate a change in the description of the physical reality. In General Relativity there are three fundamental kinds of…

General Relativity and Quantum Cosmology · Physics 2023-10-03 Jaume de Haro , Shin'ichi Nojiri , S. D. Odintsov , V. K. Oikonomou , Supriya Pan

It is demonstrated that if cosmic dark energy behaves like a fluid with equation of state $p = {\rm w} \rho (p$ and $\rho$ being pressure and energy density respectively) as well as generalized Chaplygin gas simultaneously, Big Rip or Big…

Astrophysics · Physics 2007-05-23 S. K. Srivastava

A combination of recent observational results has given rise to what is currently known as the dark energy problem. Although several possible candidates have been extensively discussed in the literature to date the nature of this dark…

Astrophysics · Physics 2009-11-07 Abha Dev , J. S. Alcaniz , Deepak Jain

The properties of future singularities are investigated in the universe dominated by dark energy including the phantom-type fluid. We classify the finite-time singularities into four classes and explicitly present the models which give rise…

High Energy Physics - Theory · Physics 2009-09-17 Shin'ichi Nojiri , Sergei D. Odintsov , Shinji Tsujikawa

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

The equation of state of Chaplygin Gas is one of the simplest ways to illustrate dark energy effects during the late time. Indeed, while one uses the equation of state of Chaplygin Gas, the continuity equation gives specific energy density…

General Physics · Physics 2018-07-20 H. R. Fazlollahi

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 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

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

Astrophysics · Physics 2007-05-23 O. Bertolami

The present study deals with dissipative future universe without big rip in context of Eckart formalism. The generalized chaplygin gas, characterized by equation of state $p=-\frac{A}{\rho^\frac{1}{\alpha}}$, has been considered as a model…

General Relativity and Quantum Cosmology · Physics 2011-04-06 Anil Kumar Yadav

Phantom dark energy models with an equation of state parameter $w < -1$ lead generically to a future big rip singularity, in which the dark energy density becomes infinite in a finite time. Current limits on dark energy constrain $w$ to be…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-20 Robert J. Scherrer , Oem Trivedi

We investigate various dark energy models by taking into account the thermal effects induced from Hawking radiation on the apparent horizon of the Universe, for example near a finite-time future singularity. If the dark energy density…

General Relativity and Quantum Cosmology · Physics 2021-02-17 Artyom V. Astashenok , Sergei D. Odintsov , Vasilis K. Oikonomou
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