English
Related papers

Related papers: Chaplygin electron gas model

200 papers

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

Effective mass and energy are investigated using the Schwinger-Dyson equation (SDE) in the complex plane. As simple examples, we solve the SDE for the (1+1)-dimensional model and the strongly coupled quantum electrodynamics (QED). We also…

High Energy Physics - Theory · Physics 2023-07-19 Hidekazu Tanaka , Shuji Sasagawa

A new model describing the dark sector of the universe is established. The model involves Bose-Einstein condensate (BEC) as dark energy (DE) and an excited state above it as dark matter (DM). The condensate is assumed to have a negative…

General Relativity and Quantum Cosmology · Physics 2011-05-24 V. A. Popov

We study the cosmological scenario arising from the dynamics of a generalized Chaplygin gas. The equation of state of the system is given in terms of the energy density, $\rho$, and pressure, $p$, by the relationship $p = -…

Astrophysics · Physics 2007-05-23 M. C. Bento , O. Bertolami , A. A. Sen

This paper analyzes the vanishing pressure limit of solutions to the Aw-Rascle model and the perturbed Aw-Rascle model for modified Chaplygin gas. Firstly, the Riemann problem of the Aw-Rascle model is solved constructively. A special delta…

Analysis of PDEs · Mathematics 2014-10-07 Jinhuan Wang , Jinjing Liu , Hanchun Yang

We provide new exact solutions to the Einstein-Maxwell system of equations which are physically reasonable. The spacetime is static and spherically symmetric with a charged matter distribution. We utilise an equation of state which is…

General Relativity and Quantum Cosmology · Physics 2015-06-12 S. D. Maharaj , P. Mafa Takisa

We here study extended classes of logotropic fluids as \textit{unified dark energy models}. Under the hypothesis of the Anton-Schmidt scenario, we consider the universe obeying a single fluid whose pressure evolves through a logarithmic…

General Relativity and Quantum Cosmology · Physics 2019-04-16 Kuantay Boshkayev , Rocco D'Agostino , Orlando Luongo

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

This manuscript investigate the dark energy Bianchi type-I cosmological models in presence of generalized Chaplygin gas, variable gravitational and cosmological constants. In this manuscript, exact solutions of Einstein field equations are…

General Relativity and Quantum Cosmology · Physics 2022-02-11 N. Hulke , G. P. Singh , Binaya K Bishi

We study the spherical top-hat collapse in Einstein gravity and loop quantum cosmology by taking the non-linear evolution of viscous modified variable chaplygin gas and viscous generalized cosmic chaplygin gas. We calculate the equation of…

General Relativity and Quantum Cosmology · Physics 2016-11-09 Abdul Jawad , Ayesha Iqbal

We establish sharp energy decay rates for a large class of nonlinearly first-order damped systems, and we design discretization schemes that inherit of the same energy decay rates, uniformly with respect to the space and/or time…

Analysis of PDEs · Mathematics 2015-12-17 Fatiha Alabau-Boussouira , Yannick Privat , Emmanuel Trélat

We explicitly demonstrate that, contrary to recent claims, the dynamics of a generalized Chaplygin gas model with an equation of state $p=-C$ (where $C$ is a positive constant) is equivalent to that of a standard $\Lambda$CDM model to first…

Astrophysics · Physics 2009-11-10 P. P. Avelino , L. M. G. Beca , J. P. M. de Carvalho , C. J. A. P. Martins

The generalized Chaplygin gas is usually defined as a barotropic perfect fluid with an equation of state $p=-A \rho^{-\alpha}$, where $\rho$ and $p$ are the proper energy density and pressure, respectively, and $A$ and $\alpha$ are positive…

General Relativity and Quantum Cosmology · Physics 2018-08-22 V. M. C. Ferreira , P. P. Avelino

We consider explicit two-level three-point in space finite-difference schemes for solving 1D barotropic gas dynamics equations. The schemes are based on special quasi-gasdynamic and quasi-hydrodynamic regularizations of the system. We…

Numerical Analysis · Mathematics 2026-01-05 A. Zlotnik , T. Lomonosov

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 work we present a theoretical study of EELS (electron-energy-loss spectroscopy) experiments on the ${\rm C}_{60}$ molecule. Our treatment of the problem is based on the simple two-fluid model originally proposed for the description…

Mesoscale and Nanoscale Physics · Physics 2009-10-31 D. A. Gorokhov , R. A. Suris , V. V. Cheianov

The generalized Chaplygin gas model is characterized by the equation of state $p = - \frac{A}{\rho^\alpha}$. It is generally stated that the case $\alpha = 0$ is equivalent to a model with cosmological constant and dust ($\Lambda CDM$). In…

Astrophysics · Physics 2009-11-10 J. C. Fabris , S. V. B. Gonçalves , R. de Sá Ribeiro

We consider an extended Chaplygin gas equation of state which is driven from D-brane action and construct a cosmological model based on this equation of state. In this regard, we compute the scale factor of the model under a certain…

General Relativity and Quantum Cosmology · Physics 2021-02-03 Behnam Pourhassan , Hoda Farahani , Sudhaker Upadhyay

The class of Chaplygin gas models regarded as a candidate of dark energy can be realized by a scalar field, which could drive the variation of the fine structure constant $\alpha$ during the cosmic time. This phenomenon has been observed…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-12 Chao-Jun Feng , Xin-Zhou Li

In this work we provide a framework for modeling compact stars in which the interior matter distribution obeys a generalised Chaplygin equation of state. The interior geometry of the stellar object is described by a spherically symmetric…

General Relativity and Quantum Cosmology · Physics 2016-05-05 Piyali Bhar , Megan Govender , Ranjan Sharma