English
Related papers

Related papers: Class I polytropes for anisotropic matter

200 papers

In this paper we consider the Boltzmann equation modelling the motion of a polyatomic gas where the integration collision operator in comparison with the classical one involves an additional internal energy variable $I\in\mathbb{R}_+$ and a…

Analysis of PDEs · Mathematics 2023-06-05 Renjun Duan , Zongguang Li

The very accurate analytical solutions are found to Lane-Emden equation of arbitrary index, n, using Picard type iteration scheme and rational Pade approximants. For n=2 the dimensionless polytropic "radius" and "mass" are 4.35287459595 and…

Astrophysics · Physics 2009-09-25 Zakir F. Seidov

A model of compact object coupled to inhomogeneous anisotropic dark energy is studied. It is assumed a variable dark energy that suffers a phase transition at a critical density. The anisotropic Lambda-Tolman-Oppenheimer-Volkoff equations…

General Relativity and Quantum Cosmology · Physics 2011-05-12 Cristian R. Ghezzi

In this paper, we develop a new class of models for a compact star with anisotropic stresses inside the matter distribution. By assuming a linear equation of state for the anisotropic matter composition of the star we solve the Einstein…

General Relativity and Quantum Cosmology · Physics 2021-11-16 Shyam Das , Saibal Ray , Maxim Khlopov , K. K. Nandi , Bikram Keshari Parida

In the present investigation an exact generalized model for anisotropic compact stars of embedding class one is sought for under general relativistic background. The generic solutions are verified by exploring different physical aspects,…

General Physics · Physics 2017-02-01 S. K. Maurya , Y. K. Gupta , Saibal Ray , Debabrata Deb

This paper uses the definition of complexity for a static spherically symmetric spacetime and extends it to the case of charged distribution. We formulate the Einstein-Maxwell field equations corresponding to the anisotropic interior and…

General Relativity and Quantum Cosmology · Physics 2023-06-02 M. Sharif , Tayyab Naseer

Transport coefficients associated with the mass flux of an impurity immersed in a granular gas under simple shear flow are determined from the inelastic Boltzmann equation. A normal solution is obtained via a Chapman-Enskog-like expansion…

Statistical Mechanics · Physics 2009-11-11 Vicente Garzo

We investigate various anisotropic spherical distributions of charged celestial bodies within the context of f(R) gravity, where R represents the Ricci scalar. The properties of specific charged compact objects are analyzed by using the…

General Relativity and Quantum Cosmology · Physics 2025-05-13 W. U. Rahman , M. Ilyas , Yi Zhong , De-Liang Yao

The main aim of this study is to examine the behaviour of physical parameters of an anisotropic compact star model demonstrating spherical symmetry in F(Q) modified gravity. To evaluate the behaviour and the stability of an anisotropic…

General Relativity and Quantum Cosmology · Physics 2025-05-26 Sat Paul , Jitendra Kumar , S. K. Maurya

In arbitrary dimension, we consider the Einstein-Maxwell Lagrangian supplemented by the more general quadratic-curvature corrections. For this model, we derive four classes of charged Lifshitz black hole solutions for which the metric…

High Energy Physics - Theory · Physics 2015-03-25 Moises Bravo-Gaete , Mokhtar Hassaine

In the present article, we have constructed static anisotropic compact star models of Einstein field equations for the spherical symmetric metric of embedding class one. By assuming the particular form of metric function $\nu$, We have…

General Relativity and Quantum Cosmology · Physics 2016-11-23 Piyali Bhar , S. K. Maurya , Y. K. Gupta , Tuhina Manna

We consider the problem of integrability of the Poisson equations describing spatial motion of a rigid body in the classical nonholonomic Suslov problem. We obtain necessary conditions for their solutions to be meromorphic and show that…

Mathematical Physics · Physics 2015-05-13 Yuri Fedorov , Andrzej J. Maciejewski , Maria Przybylska

The condition for pressure isotropy is reduced to a recurrence equation with variable, rational coefficients of order three. We prove that this difference equation can be solved in general. Consequently we can find an exact solution to the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 A. J. John , S. D. Maharaj

We give existence and regularity results for solutions of some nonlinear elliptic problems. The equations we deal with are modeled on a problem which involves in its principal part an anisotropic operator, a Hardy-type potential, and a…

Analysis of PDEs · Mathematics 2014-01-28 Francesco Della Pietra , Nunzia Gavitone

In this paper we study solutions of the critical Lane-Emden equation in higher space dimensions. We show that after certain transformations the general solution can be written in terms of elliptic functions. We restrict ourselves to real…

Mathematical Physics · Physics 2017-05-10 Radoslaw Antoni Kycia , Galina Filipuk

We present a set of polynomial equations that provides models of the lattice Boltzmann theory for any required level of accuracy and for any dimensional space in a general form. We explicitly derive two- and three-dimensional models…

Mathematical Physics · Physics 2015-05-28 Jae Wan Shim

In this paper, we study the electromagnetic effects on stability of spherically symmetric anisotropic fluid distribution satisfying two polytropic equations of state and construct the corresponding generalized Tolman Oppenheimer Volkoff…

General Relativity and Quantum Cosmology · Physics 2016-11-23 M. Sharif , Sobia Sadiq

In this paper, we develop a new relativistic compact stellar model for a spherically symmetric anisotropic matter distribution. The model has been obtained through generating a new class of solutions by invoking the Tolman {\em ansatz} for…

General Relativity and Quantum Cosmology · Physics 2020-11-25 Piyali Bhar , Shyam Das , Bikram Keshari Parida

In mathematical physics, the pressure function is determined by the equation of state. There are two existing barotropic state equations: the state equation for polytropic gas with adiabatic index greater than or equal to 1 and the state…

Analysis of PDEs · Mathematics 2019-01-29 Ka Luen Cheung , Sen Wong

We solve the equation of the equilibrium of the gravitating body, with a polytropic equation of state of the matter $P=K\rho^{\gamma}$, with $\gamma=1+1/n$, in the frame of the Newtonian gravity, with non-zero cosmological constant…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-25 M. Merafina , G. S. Bisnovatyi-Kogan , S. O. Tarasov