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In this paper, we study interacting extended Chaplygin gas as dark matter and quintessence scalar field as dark energy with an effective $\Lambda$-term in Lyra manifold. As we know Chaplygin gas behaves as dark matter at the early universe…

General Relativity and Quantum Cosmology · Physics 2016-01-20 H. Saadat

We study the impact of a generalized Chaplygin gas as a candidate for dark energy on CMB anisotropies. The generalized Chaplygin gas is a fluid component with an exotic equation of state, $p = - A/\rho^\alpha$ (a polytropic gas with…

Astrophysics · Physics 2009-11-07 Daniela Carturan , Fabio Finelli

A Universe containing uniform magnetic fields, strings, or domain walls is shown to have an ellipsoidal expansion. This case has motivations from observational cosmology especially the anomaly concerning the low quadrupole amplitude…

General Relativity and Quantum Cosmology · Physics 2020-06-25 Mohamed Lamine Abdelali , Noureddine Mebarki

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

A model of an emergent universe is obtained in brane world. Here the bulk energy is in the form of cosmological constant, while the brane consists of the Chaplygin gas with the modified equation of state such as $p=A\rho-B/\rho$. Initially…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Asit Banerjee , Tanwi Bandyopadhyay , Subenoy Chakraborty

We present a modified cosmological scenario that arises from the application of non-extensive thermodynamics with varying exponent. We extract the modified Friedmann equations, which contain new terms quantified by the non-extensive…

General Relativity and Quantum Cosmology · Physics 2019-03-27 Shin'ichi Nojiri , Sergei D. Odintsov , Emmanuel N. Saridakis

We extend the Chaplygin gas model for dark matter and dark energy unification by promoting the Chaplygin gas parameter A to the potential for an extra scalar with canonical kinetic energy. The hybrid model allows for accelerated Hubble…

Astrophysics · Physics 2009-11-10 Neven Bilic , Gary B. Tupper , Raoul D. Viollier

In this paper, we consider three different models of dark energy in higher dimensional space-time and discuss about some cosmological parameters numerically. The first model is a single component universe including viscous varying modified…

General Relativity and Quantum Cosmology · Physics 2014-06-13 M. Khurshudyan , J. Sadeghi , M. Hakobyan , H. Farahani , R. Myrzakulov

In the framework of $f(Q)$ gravity, where gravity emerges from non-metricity $Q$, we explore the cosmological implications of its non-minimal coupling to matter. Inspired by the recent success of Chaplygin gas models in explaining dark…

General Relativity and Quantum Cosmology · Physics 2025-10-28 Nakul Aggarwal , Ali Pourmand , Fatimah Shojai , Harish Parthasarathy

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

A large number of recent observational data strongly suggest that we live in a flat, accelerating Universe composed of $\sim$ 1/3 of matter (baryonic + dark) and $\sim$ 2/3 of an exotic component with large negative pressure, usually named…

Astrophysics · Physics 2015-06-24 J. A. S. Lima

This paper investigates the accelerated cosmic expansion in the late Universe by examining two dark energy models, viscous modified Chaplygin gas (VsMCG) and variable modified Chaplygin gas (VMCG), within loop quantum cosmology alongside…

General Relativity and Quantum Cosmology · Physics 2024-08-12 Rownak Kundu , Ujjal Debnath , Himanshu Chaudhary , G. Mustafa

Motivated by the recent increased interest in energy non-conserving models in cosmology, we extend the analysis of the cosmological consequences of the Classical Channel Model of Gravity (CCG). This model is based on the classical-quantum…

General Relativity and Quantum Cosmology · Physics 2017-06-09 Romain Pascalie , Natacha Altamirano , Robert B. Mann

In this paper we study the perturbations of a cosmic multi-fluid medium consisting of radiation, dust and a Chaplygin gas. To do so, we follow the 1 + 3 covariant formalism and derive the evolution equations of the fluctuations in the…

General Relativity and Quantum Cosmology · Physics 2020-10-27 Shambel Sahlu , Heba Sami , Anna-Mia Swart , Thato Tsabone , Maye Elmardi , Amare Abebe

Integrability conditions arising from general irrotational fluid-flow considerations of a universe dominated by cosmic dark fluids will be investigated under special assumptions on the nature of the spacetime shear. Special emphasis will be…

General Relativity and Quantum Cosmology · Physics 2022-05-24 Amare Abebe

In this paper we investigate the role played by dark energy in the form of Generalized cosmic Chaplygin gas in an accelerating universe described by FRW cosmology. We have tried to describe the model from the theoretical point of view of a…

General Relativity and Quantum Cosmology · Physics 2013-07-11 Prabir Rudra

We study the polytropic gas scenario as the unification of dark matter and dark energy. We fit the model parameters by using the latest observational data including type Ia supernovae, baryon acoustic oscillation, cosmic microwave…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-01 K. Karami , Z. Safari , S. Asadzadeh

We have considered a model of two component mixture i.e., mixture of Chaplygin gas and barotropic fluid with tachyonic field. In the case, when they have no interaction then both of them retain their own properties. Let us consider an…

General Relativity and Quantum Cosmology · Physics 2015-03-17 Piyali Bagchi Khatua , Ujjal Debnath

In this paper, we examine the thermodynamic features of an exotic fluid known as modified cosmic Chaplygin gas in the context of homogeneous isotropic universe model. For this purpose, the behavior of physical parameters are discussed that…

General Relativity and Quantum Cosmology · Physics 2018-10-05 M. Sharif , Sara Ashraf

One of the most compelling goals of observational cosmology is the characterisation of the properties of the dark energy component thought to be responsible for the recent acceleration of the universe, including its possible dynamics. In…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-08 C. J. A. P. Martins , M. Prat Colomer
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