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Related papers: Polytropic stars in three-dimensional spacetime

200 papers

We study a spherically symmetric spacetime made of anisotropic fluid of which radial equation of state is given by $p_1 = -\rho$. This provides analytic solutions and a good opportunity to study the static configuration of black hole plus…

General Relativity and Quantum Cosmology · Physics 2018-12-27 Inyong Cho , Hyeong-Chan Kim

In this article, we assume that a cold charged perfect fluid is constructing a spherical relativistic star. Our purpose is the investigation of the dynamical properties of its exterior geometry, through simulating the geodesic motion of a…

General Relativity and Quantum Cosmology · Physics 2015-03-19 Mohsen Fathi

We develop a new formalism to study the dynamics of fluid polytropes in three dimensions. The stars are modeled as compressible ellipsoids and the hydrodynamic equations are reduced to a set of ordinary differential equations for the…

Astrophysics · Physics 2009-10-22 Dong Lai , Frederic A. Rasio , Stuart L. Shapiro

A family of exact relativistic stellar models is described. The family generalizes Buchdahl's n=1 polytropic solution. The matter content is a perfect fluid and, excluding Buchdahl's original model, it behaves as a liquid at low pressures…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Kjell Rosquist

Polytropic stars are useful tools for learning about stellar structure without the complexity of comprehensive stellar models. These models rely on a certain power-law correlation between the star's pressure and density. This paper proposes…

General Relativity and Quantum Cosmology · Physics 2024-07-19 Akashdip Karmakar , Ujjal Debnath , Pramit Rej

Solutions to equilibrium sequences of irrotational binary polytropic stars in Newtonian gravity are expanded in a power of $\epsilon=a_0/R$, where R and $a_0$ are the orbital separation of the binary system and the radius of each star for…

Astrophysics · Physics 2009-10-31 Keisuke Taniguchi , Takashi Nakamura

We investigate perfect fluid stars in $(2+1)$ dimension in pseudo spheroidal spacetime with the help of Vaidya-Tikekar metric where the physical $3$-space ($t=$ constant) is described by pseudo-spheroidal geometry. Here the spheroidicity…

General Physics · Physics 2017-06-07 D. Shee , S. Ghosh , F. Rahaman , B. K. Guha , Saibal Ray

We have investigated spherically symmetric spacetimes which contain a perfect fluid obeying the polytropic equation of state and admit a kinematic self-similar vector of the second kind which is neither parallel nor orthogonal to the fluid…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Hideki Maeda , Tomohiro Harada , Hideo Iguchi , Naoya Okuyama

The trace-free Einstein equations contain one equation less than the complete field equations. In a static and spherically symmetric spacetime, the number of field equations is thus reduced to two. The equation of pressure isotropy of…

General Relativity and Quantum Cosmology · Physics 2024-03-27 Sudan Hansraj , Chevarra Hansraj , Njabulo Mkhize , Abdelghani Errehymy , Christian G. Boehmer

We present a new system of equations that fully characterizes adiabatic, radial perturbations of perfect fluid stars within the theory of general relativity. The properties of the system are discussed, and, provided that the equilibrium…

General Relativity and Quantum Cosmology · Physics 2024-05-14 Paulo Luz , Sante Carloni

We construct perfect fluid metrics corresponding to spacelike surfaces invariant under a 1-dimensional group of isometries in 3-dimensional Minkowski space. Under additional assumptions we obtain new cosmological solutions of Bianchi type…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Adam Szereszewski , Jacek Tafel

We present new anisotropic generalization of Buchdahl [1] type perfect fluid solution by using the method of earlier work [2]. In similar approach we have constructed the new pressure anisotropy factor ${\Delta}$ by the help both the metric…

General Relativity and Quantum Cosmology · Physics 2015-11-26 S. K. Maurya , Y. K. Gupta , Baiju Dayanandan , M. K. Jasim , Ahmed Al-Jamel

This paper is an investigation of the stability of some ideal stars. It is in- tended as a study in General Relativity, with emphasis on the coupling to matter, eventually aimed at a better understanding of very strong gravitational fields…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Christian Fronsdal

Circularly orbiting black hole-gaseous star close binary systems are examined by using numerically exact stationary configurations in the framework of Newtonian gravity. We have chosen a polytropic star for the fluid component of the binary…

Astrophysics · Physics 2009-10-30 Koji Uryu , Yoshiharu Eriguchi

We consider a self-consistent system of Bianchi type-I (BI) gravitational field and a binary mixture of perfect fluid and dark energy. The perfect fluid is taken to be the one obeying the usual equation of state, i.e., $p = \zeta \ve$, with…

General Relativity and Quantum Cosmology · Physics 2015-05-01 Bijan Saha

In this work, we derive the general solutions for a cylindrically symmetric space-time filled with a cosmological perfect fluid obeying $p=\gamma \rho$ ($0\leq \gamma \leq 1$), where $\gamma=1$ represents a stiff or Zeldovich fluid. Using…

General Relativity and Quantum Cosmology · Physics 2026-04-06 Tiberiu Harko , Francisco S. N. Lobo , Man Kwong Mak

In the present paper we develop an algorithm for all spherically symmetric anisotropic charged fluid distribution. Considering a new source function $\nu(r)$ we find out a set of solutions which is physically well behaved and represent…

General Relativity and Quantum Cosmology · Physics 2017-06-12 S. K. Maurya , Y. K. Gupta , Saibal Ray

We present a spherically symmetric solution of the general relativistic field equations in isotropic coordinates for anisotropic neutral fluid, compatible with a super dense star modeling by considering a specific choice of anisotropy…

General Relativity and Quantum Cosmology · Physics 2014-10-23 Neeraj Pant , Narendra Pradhan , Manuel Malaver

The aim of this paper is to examine some obtained exact solutions of the Einstein-Maxwell equations, especially their properties from a chronological point of view. Each our spacetime is stationary cylindrically symmetric and it is filled…

General Relativity and Quantum Cosmology · Physics 2009-10-31 P. Klepac , J. Horsky

Gravitational collapse of a spherically symmetric homogeneous perfect barotropic fluid with linear as well as polytropic type Equation of State (EoS) has been investigated in the framework of a linear model of $f(R,T)$ gravity. This…

General Relativity and Quantum Cosmology · Physics 2020-05-06 Karim Mosani , Gauranga C. Samanta