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We analyze the properties of a generic cosmological fluid described by the van der Waals equation of state. Exact solutions for the energy density evolution are found as implicit functions of the scale factor for a flat…

General Relativity and Quantum Cosmology · Physics 2016-02-11 Rudinei C. S. Jantsch , Marcus H. B. Christmann , Gilberto M. Kremer

In this paper we proposed to use the group of analysis of symmetries of the dynamical system to describe the evolution of the Universe. This methods is used in searching for the unknown equation of state. It is shown that group of…

Astrophysics · Physics 2009-11-24 Marek Szydlowski , Wlodzimierz Godlowski , Radoslaw Wojtak

The cosmological dynamics of a quintessence model based on real gas with general equation of state is presented within the framework of a three-dimensional dynamical system describing the time evolution of the number density, the Hubble…

General Relativity and Quantum Cosmology · Physics 2019-02-05 Rossen I. Ivanov , Emil M. Prodanov

A dark Friedman-Robertson-Walker fluid governed by a non-linear inhomogeneous equation of state is considered which can be viewed as a conveniently simple paradigm for a whole class of models which exhibit phase transitions from a…

General Relativity and Quantum Cosmology · Physics 2008-11-26 I. Brevik , E. Elizalde , O. Gorbunova , A. V. Timoshkin

Classical as well as quantum features of the late-time evolution of cosmological models with fluids obeying a Shan-Chen-like equation of state are studied. The latter is of the type $p=w_{\rm eff}(\rho)\,\rho$, and has been used in previous…

General Relativity and Quantum Cosmology · Physics 2016-02-17 Donato Bini , Giampiero Esposito , Andrea Geralico

We systematically study the evolution of the Friedmann-Robertson-Walker (FRW) universe coupled with a cosmological constant $\Lambda$ and a perfect fluid that has the equation of state $p=w\rho$, where $p$ and $\rho$ denote, respectively,…

In the present article we analyze, by means of the statefinder parameter formalism, some universe models introduced by Brevik and co-workers. We determine constants that earlier were left unspecified, in terms of observable quantities. It…

Astrophysics · Physics 2008-12-16 Oyvind Gron

In this present work, we try to build up a cosmological model using a non-canonical scalar field within the framework of a spatially flat FRW space-time. In this context, we have considered four different parametrizations of the equation of…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Abdulla Al Mamon , Sudipta Das

This paper is devoted to investigate the thermodynamic stability of a generic cosmological fluid known as Van der Waals fluid in the context of flat FRW universe. It is treated as a perfect fluid that obeys the equation of state…

General Relativity and Quantum Cosmology · Physics 2021-10-25 Mahasweta Biswas , Sayani Maity , Ujjal Debnath

We demonstrate two periodic or quasi-periodic generalizations of the Chaplygin gas (CG) type models to explain the origins of dark energy as well as dark matter by using the Weierstrass $\wp(t)$, $\sigma(t)$ and $\zeta(t)$ functions with…

General Relativity and Quantum Cosmology · Physics 2012-11-22 Kazuharu Bamba , Ujjal Debnath , Kuralay Yesmakhanova , Petr Tsyba , Gulgasyl Nugmanova , Ratbay Myrzakulov

The evolution of a Universe confined onto a 3-brane embedded in a five-dimensional space-time is investigated where the cosmological fluid on the brane is modeled by the van der Waals equation of state. It is shown that the Universe on the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 G. M. Kremer

The following paper has been motivated from recent works of Kremer, G.M [1, 4], Vardiashvili, G [2], Jantsch, R.C [3], Capozziello, S [5] on Van-Der-Waals EOS cosmology. The main aim for this paper is to analyze the thermodynamics of a…

General Relativity and Quantum Cosmology · Physics 2021-10-27 Shouvik Sadhukhan , Alokananda Kar , Surajit Chattopadhyay

Abandoning the perfect fluid hypothesis, we investigate here the possibility that the dark energy equation of state (EoS) $w$ is a nonlinear function of the energy density $\rho$. To this aim, we consider four different EoS describing…

Astrophysics · Physics 2009-11-13 V. F. Cardone , C. Tortora , A. Troisi , S. Capozziello

Considering a homogeneous and isotropic universe characterized by the Friedmann-Lema\^itre-Robertson-Walker (FLRW) line element, in this work, we have prescribed a general formalism for the cosmological solutions when the equation of state…

General Relativity and Quantum Cosmology · Physics 2018-01-10 Anadijiban Das , Asit Banerjee , Subenoy Chakraborty , Supriya Pan

The universe media is considered as a non-perfect fluid with bulk viscosity and described by a more general equation of state. We assume the bulk viscosity is a linear combination of the two terms: one is constant, and the other is…

Astrophysics · Physics 2009-03-19 Xin-He Meng , Jie Ren , Ming-Guang Hu

The evolution of spatially homogeneous and isotropic cosmological models containing a perfect fluid with equation of state p=w\rho\ and a cosmological constant \Lambda\ is investigated for arbitrary combinations of w and \Lambda, using…

Physics Education · Physics 2012-09-19 Sebastiano Sonego , Vittorino Talamini

In this paper the accelerating expansion of our universe at the late cosmic evolution time in a generally modified (extended) \emph{Chaplygin gas} (Dark Fluid) model is detailed, which is characterized by two parameters ($m$, $\alpha$).…

Astrophysics · Physics 2007-05-23 Xin-He Meng , Ming-Guang Hu , Jie Ren

In this paper we study the evolution of spatially homogeneous and anisotropic Bianchi type-I Universe models with the cosmological constant, \Lambda, and filled with nonlinear viscous fluid. The dynamical equations for these models are…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Nouraddin Mostafapoor , Oyvind Gron

We investigate a flat Emergent Universe (EU) with a nonlinear equation of state which is equivalent to three different compositions of fluids. In the EU, initially, the evolution of the universe began with no interaction, but as time…

General Relativity and Quantum Cosmology · Physics 2023-09-19 Anirban Chanda , Bikash Chandra Roy , Kazuharu Bamba , Bikash Chandra Paul

The renowned van der Waals (VDW) state equation quantifies the equilibrium relationship between pressure $P$, volume $V$ and temperature $k_{B}T$ of a real gas. We assign new variable interpretations adapted to the economic context: $P…

Adaptation and Self-Organizing Systems · Physics 2024-04-12 Max-Olivier Hongler , Olivier Gallay , Fariba Hashemi
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