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Related papers: Constraining Modified Chaplygin gas parameters

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In this letter we consider two different models of our present universe. We choose the models which are consisting different sets of two seperate fluids. The first one of each set tries to justify the late time acceleration and the second…

General Physics · Physics 2019-03-27 Promila Biswas , Ritabrata Biswas

Understanding the accelerating expansion of the Universe remains a fundamental challenge in modern cosmology. In this paper, we investigate a cosmological model parametrized by a generalized variable deceleration parameter to elucidate the…

General Relativity and Quantum Cosmology · Physics 2023-09-29 M. Koussour , N. Myrzakulov , Alnadhief H. A. Alfedeel , F. Awad , M. Bennai

We investigate the unification scenario provided by the generalised Chaplygin gas model (a perfect fluid characterized by an equation of state p = -A/\rho^{\alpha}). Our concerns lie with a possible tension existing between background…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-18 Juliano Pereira Campos , Júlio César Fabris , Rafael Perez , Oliver F. Piattella , Hermano Velten

We present a scalar-field formulation of the generalized Chaplygin gas (GCG) and modified Chaplygin gas (MCG) models, in which the cosmic fluid dynamics are reproduced by canonical Lagrangians with analytically derived energy density…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-23 Yi-Syuan Wu , Chuan-Jui Li , W. F. Kao

In the current framework of Einstein's equations in general relativity (GR), gravity is described by the spacetime curvature. However, there are other descriptions where the origin of gravity can be understood through torsion and…

General Relativity and Quantum Cosmology · Physics 2022-12-02 Nakul Aggarwal , Ali Pourmand , Fatimah Shojai , Harish Parthasarathy

In this paper, we consider a comprehensive investigation of the cosmological model described by $f(R,T) = R + 2\lambda T$ (where $\lambda$ represents a free parameter) in light of the most recent observational data. By constraining the…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-29 N. Myrzakulov , M. Koussour , Alnadhief H. A. Alfedeel , E. I. Hassan

We show that the observed rotation curves of spiral galaxies constrain the sound speed of the dark matter to be $c_s < 10^{-4} c$, where $c$ is the speed of light in vacuum. Using the Modified Chaplygin Gas as a representative example of a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-06 P. P. Avelino , V. M. C. Ferreira

In this paper, we present an accelerating cosmological model by constraining the free parameters using the cosmological datasets in an extended symmetric teleparallel gravity for the flat and anisotropic space-time. We employ a time…

General Relativity and Quantum Cosmology · Physics 2023-06-27 S. A. Narawade , M. Koussour , B. Mishra

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

A new class of accelerating cosmological models driven by a one-parameter version of the general Chaplygin-type equation of state is proposed. The simplified version is naturally obtained from causality considerations with basis on the…

Astrophysics · Physics 2010-11-05 J. A. S. Lima , J. V. Cunha , J. S. Alcaniz

This paper investigates regarding cosmological implications of a bulk viscous modified Chaplygin gas (MCG) in (2+1)-dimensional Friedmann-Robertson-Walker spacetime, incorporating both theoretical analysis and observational constraints. We…

General Relativity and Quantum Cosmology · Physics 2025-04-29 Praveen Kumar Dhankar , Aritra Sanyal , Albert Munyeshyaka , Saibal Ray , Behnam Pourhassan

This paper explores the possibility of treating the exotic Chaplygin-gas (CG) fluid model as some manifestation of an $f(T)$ gravitation. To this end, we use the different cosmological CG equations of state, compare them with the equation…

General Relativity and Quantum Cosmology · Physics 2019-10-02 Shambel Sahlu , Joseph Ntahompagaze , Maye Elmardi , Amare Abebe

In this paper we study the interaction between the general form of viscous varying modified cosmic Chaplygin gas and the Tachyon fluid in the framework of Einstein gravity. We want to reconstruct the Tachyon potential and total equation of…

General Relativity and Quantum Cosmology · Physics 2013-08-05 Jafar Sadeghi , Hoda Farahani

We explore the late time cosmological dynamics of the Universe within the framework of $f(Q,\mathcal{L}_{m})$ gravity by considering the specific form $f(Q, \mathcal{L}_m)=-Q+2\mathcal{L}_m+\gamma$. To describe the cosmic pressure…

General Relativity and Quantum Cosmology · Physics 2025-08-08 Amit Samaddar , S. Surendra Singh

We study the main cosmological properties of the Generalized Chaplygin Gas (GCG) dark energy model at the background and perturbation levels. By using the latest cosmological data in both the background and perturbation levels, we implement…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-14 S. F. Salahedin , M. Malekjani , K. Y. Roobiat , R. Pazhouhesh

One approach in modern cosmology consists in supposing that dark matter and dark energy are different manifestations of a single `quartessential' fluid. Following such idea, this work presents a study of the evolution of perturbations of…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Sandro Silva e Costa , Maximiliano Ujevic , Alesandro Ferreira dos Santos

We study the Generalized Chaplygin gas model (GCGM) using Gamma-ray bursts as cosmological probes. In order to avoid the so-called circularity problem we use cosmology-independent data set and Bayesian statistics to impose constraints on…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-19 R. C. Freitas , S. V. B. Gonçalves , H. E. S. Velten

The generalized Chaplygin gas (GCG), which has an unusual perfect fluid equation of state, is another promising candidate for dark energy. We investigate the GCG scenario coupled with a baryonic matter in a newly suggested $f(Q,T)$ gravity,…

General Relativity and Quantum Cosmology · Physics 2022-06-24 Gaurav N. Gadbail , Simran Arora , P. K. Sahoo

In the framework of spatially flat Friedmann-Lemaitre-Robertson-Walker (FLRW) space-time, we investigate a two-fluid cosmological model where a tachyon scalar field with self-interacting potential and a modified chaplygin gas with…

General Relativity and Quantum Cosmology · Physics 2024-12-25 Goutam Mandal , Sujay Kr. Biswas

In this paper, a general entropy-corrected FRW cosmological model has been presented in which a deceleration-to-acceleration transition occurs according to recent observations. We found that the case for the flat universe ($k=0$), supported…

General Relativity and Quantum Cosmology · Physics 2019-10-23 Nasr Ahmed , Sultan Z. Alamri
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