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Related papers: Anisotropic Quintessence stars

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In the present work we investigate the stability of the k-essence models allowing upto quadratic terms of the kinetic energy. The system of field equations is written as an autonomous system in terms of dimensionless variables and the…

General Relativity and Quantum Cosmology · Physics 2019-05-29 Abhijit Chakraborty , Anandamohan Ghosh , Narayan Banerjee

Since the discovery of the accelerated expansion of the universe, it was necessary to introduce a new component of matter distribution called dark energy. The standard cosmological model considers isotropy of the pressure and assumes an…

General Relativity and Quantum Cosmology · Physics 2012-10-25 R. Chan , M. F. A. da Silva , J. F. Villas da Rocha

We model a compact relativistic body with anisotropic pressures in the presence of an electric field. The equation of state is barotropic with a linear relationship between the radial pressure and the energy density. Simple exact models of…

General Relativity and Quantum Cosmology · Physics 2015-06-17 P. Mafa Takisa , S. D. Maharaj

We set up in detail the general formalism to model polytropic general relativistic stars with anisotropic pressure. We shall consider two different possible polytropic equations, all of which yield the same Lane-Emden equation in the…

General Relativity and Quantum Cosmology · Physics 2015-06-17 L. Herrera , W. Barreto

We study the effects of anisotropic pressure on the properties of spherically symmetric, gravitationally bound objects. We consider the full general relativistic treatment of this problem and obtain exact solutions for various form of…

Astrophysics · Physics 2007-05-23 Krsna Dev , Marcelo Gleiser

This paper explored the physical acceptability conditions for anisotropic matter configurations in General Relativity. The study considered a generalized polytropic equation of state $P=\kappa {\rho}^{\gamma}+\alpha \rho -\beta$ for a…

General Relativity and Quantum Cosmology · Physics 2022-03-14 Daniel Suárez-Urango , J. Ospino , Héctor Hernández , Luis A. Núñez

A variety of observational tests seem to suggest that the universe is anisotropic. This is incompatible with the standard dogma based on adiabatic, rotationally invariant perturbations. We point out that this is a consequence of the…

Astrophysics · Physics 2009-11-11 Richard A. Battye , Adam Moss

Through the geodesic analysis of a static and axially symmetric space time, we present conditions on the state equation of an isotropic perfect fluid $p=\omega d$, when it is considered as dark matter in spiral galaxies. The main conclusion…

Astrophysics · Physics 2007-05-23 F. Siddhartha Guzman , Tonatiuh Matos , Dario Nunez , Erandy Ramirez

Present paper provides a new model of anisotropic strange star corresponding to the exterior schwarzschild metric. The Einstein field equations have been solved by utilizing the Krori Barua (KB) ansatz in presence of quintessence field…

General Relativity and Quantum Cosmology · Physics 2015-03-20 Piyali Bhar

In this paper we found a new model for compact star with anisotropic matter distribution considering the new version of Chaplygin fluid equation of state of Errehymy and Daoud (2021). We specify the particular form of the metric potential…

General Relativity and Quantum Cosmology · Physics 2022-04-29 Manuel Malaver , Rajan Iyer

An oscillating scalar field as a quintessence model for dark energy is proposed. The case of a power-law potential is particularly intriguing and is the focus of the present article. In this model the equation of state w_{OQ} of dark energy…

Astrophysics · Physics 2007-11-26 Je-an Gu

We introduce a power-law parameterized quintessence model for the dark energy which accelerate universe at the low redshifts while behaves as an ordinary matter for the early universe. We construct a unique scalar potential for this…

Astrophysics · Physics 2008-11-26 Sohrab Rahvar , M. Sadegh Movahed

In this work we present a model of the universe in which dark energy is modelled explicitely with both a dynamical quintessence field and a cosmological constant. Our results confirm the possibility of a future collapsing universe (for a…

Astrophysics · Physics 2009-11-07 Rolando Cardenas , Tame Gonzalez , Yoelsy Leiva , Osmel Martin , Israel Quiros

By employing modified Chaplygin fluid prescription for the dark energy, we construct slowly rotating isotropic and anisotropic dark energy stars. The slow rotation is incorporated via general relativistic Hartle-Thorne formalism; whereas…

General Relativity and Quantum Cosmology · Physics 2024-07-26 O. P. Jyothilakshmi , Lakshmi J. Naik , V. Sreekanth

This paper discusses a generalized model for compact stars, assumed to be anisotropic in nature due to the spherical symmetry and high density. After embedding the four-dimensional spacetime in a five-dimensional flat spacetime, which may…

General Physics · Physics 2018-03-09 S. K. Maurya , Debabrata Deb , Saibal Ray , P. K. F. Kuhfittig

Stars can be treated as self-gravitating fluid. In this connection, we propose a model for an anisotropic star under the relativistic framework of Krori-Barua (1975) spacetime. It is shown that the solutions are regular and singularity…

General Physics · Physics 2015-06-12 Mehedi Kalam , Farook Rahaman , Sk. Monowar Hossein , Saibal Ray

In this work, we investigate an anisotropic compact star's physical properties and stability in F(Q) gravity. The study focuses on the significance of F(Q) gravity on the structure and stability of compact star, considering non-perfect…

General Relativity and Quantum Cosmology · Physics 2024-09-26 Sat Paul , Jitendra Kumar , Sunil Kumar Maurya , Sourav Choudhary , Sweeti Kiroriwala

We present model for anisotropic compact star under the general theory of relativity of Einstein. In the study a 4-dimensional spacetime has been considered which is embedded into the 5-dimensional flat metric so that the spherically…

General Physics · Physics 2018-08-01 S. K. Maurya , Saibal Ray , Shounak Ghosh , Sarbajit Manna , Smitha T. T

The authors of the paper ''On Anisotropic Dark Energy Stars'', arXiv:0803.2508 [gr-qc], consider the equations of state $p_r=\omega \rho$ and $p_t=\omega \rho$, ignoring the fact that this implies an isotropic pressure, which places strict…

General Relativity and Quantum Cosmology · Physics 2008-05-21 Francisco S. N. Lobo

The equilibrium configurations of slowly rotating anisotropic self-gravitating fluids are computed using the extended Hartle structure equations, including anisotropic effects, derived in our previous paper. We focus on the so-called…

General Relativity and Quantum Cosmology · Physics 2025-10-20 Philip Beltracchi , Camilo Posada