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Related papers: Cosmological constraints on polytropic gas model

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A new dark energy model called "ghost dark energy" was recently suggested to explain the observed accelerating expansion of the universe. This model originates from the Veneziano ghost of QCD. The dark energy density is proportional to…

High Energy Physics - Theory · Physics 2015-03-19 A. Sheykhi , M. Sadegh Movahed

The Universe is modeled as consisting of pressureless baryonic matter and a bulk viscous fluid which is supposed to represent a unified description of the dark sector. In the homogeneous and isotropic background the \textit{total} energy…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-22 W. Zimdahl , H. E. S. Velten , W. S. Hipólito-Ricaldi

We propose a new class of cosmological unified dark sector models called "{\em Generalized Logotropic Models}". They depend on a free parameter $n$. The original logotropic model [P.H. Chavanis, Eur. Phys. J. Plus {\bf 130}, 130 (2015)] is…

General Relativity and Quantum Cosmology · Physics 2022-02-17 Hachemi B. Benaoum , Pierre-Henri Chavanis , Hernando Quevedo

A new cosmic scenario with gravitationally induced particle creation is proposed. In this model the Universe evolves from an early to a late time de Sitter era, with the recent accelerating phase driven only by the negative creation…

General Relativity and Quantum Cosmology · Physics 2015-06-22 J. A. S. Lima , L. L. Graef , D. Pavón , S. Basilakos

The interacting polytropic gas dark energy model is investigated from the viewpoint of statefinder diagnostic tool and $w-w^{\prime}$ analysis. The dependency of the statefinder parameters on the parameter of the model as well as the…

General Relativity and Quantum Cosmology · Physics 2015-06-03 M. Malekjani , A. Khodam-Mohammadi

An analysis of cosmological mixed dark matter models in spatially flat Friedmann Universe with zero $\Lambda$-term is presented. We argue that the introduction of cosmic gravity waves helps to satisfy observational constraints. The analysis…

Astrophysics · Physics 2007-05-23 E. V. Mikheeva

Dark energy is modelled by a Bose-Einstein gas of particles with an attractive interaction. It is coupled to cold dark matter, within a flat universe, for the late-expansion description, producing variations in particle-number densities.…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-11 Hiram E. Lucatero--Villaseñor , German Izquierdo , Jaime Besprosvany

We derive and analyze a class of spherically symmetric cosmological models whose source is an interactive mixture of inhomogeneous cold dark matter (DM) and a generic homogeneous dark energy (DE) fluid. If the DE fluid corresponds to a…

Astrophysics · Physics 2009-11-10 Roberto A Sussman , Israel Quiros , Osmel Martin Gonzalez

We have re-investigated Cosmology involving interaction between Dark matter and Dark Energy in the light of a new parametrization. The new parametrization is based on the hypothesis that when Dark matter and Dark Energy will interact, Dark…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-20 Arkajit Aich

By implementing the concept of polytropic structures as a scalar field gas with a dark energy-like behavior, we obtain a static spherically symmetric black hole solution in the framework of general relativity. In this paper, we study the…

General Relativity and Quantum Cosmology · Physics 2025-09-17 Y. Sekhmani , S. Zare , L. M. Nieto , H. Hassanabadi , K. Boshkayev

In this work, we studied four types of cosmological models with different mechanisms driving the accelerated expansion of the universe, include Braneworld models, Chaplygin Gas models, Emergent Dark Energy models, and cosmological torsion…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-02 Ziqiang Liu , Tonghua Liu , Xinyi Zhong , Yifei Xu , Xiaogang Zheng

While there is plentiful evidence in all fronts of experimental cosmology for the existence of a non-vanishing dark energy (DE) density \rho_D in the Universe, we are still far away from having a fundamental understanding of its ultimate…

Astrophysics · Physics 2011-07-19 Javier Grande , Ana Pelinson , Joan Sola

In this manuscript, we investigate the patterns satisfied by the cosmological anisotropy under the hypothesis of the observers being co-moving with a perfect fluid whose induced space sections are homogeneous with vanishing scalar…

General Relativity and Quantum Cosmology · Physics 2021-03-31 Leandro G. Gomes

We consider a double polytropic cosmological fluid and demonstrate that, when one constituent resembles a bare cosmological constant while the other emulates a generalized Chaplygin gas, a good description of the Universe's large-scale…

General Relativity and Quantum Cosmology · Physics 2024-03-27 Peter K. S. Dunsby , Orlando Luongo , Marco Muccino , Vineshree Pillay

In the present lore of cosmology, matter and space-time emerged from a singularity and evolved through four different regimes: inflation, radiation, dark matter and dark energy dominated eras. In the radiation and dark matter dominated…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-13 J. A. S. Lima , S. Basilakos

This paper is devoted to the investigation of modified Chaplygin gas model in the context of solvable k-essence cosmologies. For this purpose, we construct equations of state parameter of this model for some particular values of the…

General Physics · Physics 2012-07-31 M. Sharif , K. R. Yesmakhanova , S. Rani , R. Myrzakulov

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

Quintessential inflation provides a unified description of the early and late accelerated phases of the Universe, linking the inflationary epoch to the present-day dark energy-dominated era through a single scalar degree of freedom. In this…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-25 Jamerson Rodrigues , Gabriel Rodrigues , Felipe B. M. dos Santos , Simony Santos da Costa , Jailson Alcaniz

A new phenomenological dark energy model, originally associated to the large-scale structure formation and considered as a solution to the fine-tuning and coincidence problems related to the cosmological constant, was analyzed within the…

General Relativity and Quantum Cosmology · Physics 2026-03-05 A. Kazım Çamlıbel

We bring forward a generalized pressure dark energy (GPDE) model to explore the evolution of the universe. This model has covered three common pressure parameterization types and can be reconstructed as quintessence and phantom scalar…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-23 Jun-Chao Wang , Xin-He Meng
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