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Related papers: Scale invariant stellar structure

200 papers

We present a class of exact solutions of Einstein's gravitational field equations describing spherically symmetric and static anisotropic stellar type configurations. The solutions are obtained by assuming a particular form of the…

General Relativity and Quantum Cosmology · Physics 2017-10-04 T. Harko , M. K. Mak

Travelling and rotating waves are ubiquitous phenomena observed in time dependent PDEs modelling the combined effect of dissipation and non-linear interaction. From an abstract viewpoint they appear as relative equilibria of an equivariant…

Numerical Analysis · Mathematics 2018-10-30 Wolf-Jürgen Beyn , Denny Otten

This paper encompasses a set of stellar equations that administer the formation and evolution of self-gravitating, dissipative spherically symmetric fluid distributions having anisotropic stresses in the presence of electromagnetic field.…

General Relativity and Quantum Cosmology · Physics 2021-12-09 M. Z. Bhatti , Z. Tariq

We present a new formulation for numerically obtaining axisymmetric equilibrium structures of rotating stars in two spatial dimensions. With a view to apply it to the secular evolution of rotating stars, we base it on the Lagrangian…

Solar and Stellar Astrophysics · Physics 2023-03-15 Misa Ogata , Hirotada Okawa , Kotaro Fujisawa , Nobutoshi Yasutake , Yu Yamamoto , Shoichi Yamada

A self-gravitating sphere of polytropic gas (polytrope) is considered. The system of equations describing radial motions of this sphere in Lagrangian variables reduces to the only nonlinear PDE of the second order in both variables…

Fluid Dynamics · Physics 2013-12-05 Mikhail I. Ivanov

In this work, we study self-gravitating objects that obey a polytropic equation of state in hyperbolic symmetry. Specifically, we describe in detail the steps to derive the Lane-Emden equation from the structure equations of the system. To…

General Relativity and Quantum Cosmology · Physics 2025-05-29 M. Carrasco-H , E. Contreras , E. Fuenmayor , P. León

We have derived exact solutions of the isothermal Lane--Emden equation with and without rotation in a cylindrical geometry. The corresponding hydrostatic equilibria are most relevant to the dynamics of the protosolar nebula before and…

Astrophysics · Physics 2008-11-06 Dimitris M. Christodoulou , Demosthenes Kazanas

The inner structure of a star or a primordial interstellar cloud is a major topic in classical and relativistic physics. The impact that General Relativistic principles have on this structure has been the subject of many research papers. In…

General Relativity and Quantum Cosmology · Physics 2019-08-14 Mayer Humi , John Roumas

We present a full 3D numerical evolution code to study neutron stars in massive-scalar-tensor theories. The code is embedded in the Einstein Toolkit framework and its implementation constitutes a modified version of the…

General Relativity and Quantum Cosmology · Physics 2026-05-19 José Carlos Olvera M. , Daniela D. Doneva , Pablo Cerdá-Durán , José A. Font , Stoytcho S. Yazadjiev

We present a model of relativistic elastic stars featuring scale invariance. This implies a linear mass-radius relation and the absence of a maximum mass. The most compact spherically symmetric configuration that is radially stable and…

General Relativity and Quantum Cosmology · Physics 2024-04-05 Artur Alho , José Natário , Paolo Pani , Guilherme Raposo

We consider here a robust study of stellar dynamics for White Dwarf Stars with polytropic matter in the weak field approximation using the Lane-Emden equation from the brane-world scenario. We also derive an analytical solution to the…

General Relativity and Quantum Cosmology · Physics 2015-10-26 Miguel A. Garcia-Aspeitia

Scaling symmetries of the Euler-Lagrange equations are generally not variational symmetries of the action and do not lead to conservation laws. Nevertheless, by an extension of Noether's theorem, scaling symmetries lead to useful {\em…

Classical Physics · Physics 2016-09-08 Sidney Bludman , Dallas C. Kennedy

A closed mathematical model of the statistical self-gravitating system of scalar charged particles for conformal invariant scalar interactions is constructed on the basis of relativistic kinetics and gravitation theory. Asymptotic…

General Relativity and Quantum Cosmology · Physics 2015-08-13 Yurii Ignat'ev

We study oscillations of slowly rotating relativistic barotropic as well as non-barotropic polytropic stars in the Cowling approximation, including first order rotational corrections. By taking into account the coupling between the polar…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Johannes Ruoff , Adamantios Stavridis , Kostas D. Kokkotas

In this paper we consider a class of second order singular homogeneous differential equations called the Lane-Emden-type with time singularity in the drift coefficient. Lane-Emden equations are singular initial value problems that model…

Dynamical Systems · Mathematics 2024-05-15 Oday Hazaimah

The aim of this study is to construct a simple stellar model with non-uniform polytropic index. We find that the Emden equation cannot deal with the polytrope gas sphere with non-uniform polytropic index in a real star, and then we…

Solar and Stellar Astrophysics · Physics 2022-09-21 Xing Wei

A model approach to the description of static stars filled with a charged Pascal perfect fluid within the framework of general relativity is investigated. The metric is written in Bondi's radiation coordinates. The gravitational equations…

General Relativity and Quantum Cosmology · Physics 2012-01-24 A. M. Baranov

We highlight a non-canonical yet natural choice of variables for an efficient derivation of a kinetic equation for the energy density in non-isotropic systems, including internal gravity waves on a vertical plane, inertial and Rossby waves.…

Fluid Dynamics · Physics 2025-10-14 Michal Shavit , Oliver Bühler , Jalal Shatah

The inverse stellar structure problem determines the equation of state of the matter in stars from a knowledge of their macroscopic observables (e.g. their masses and radii). This problem was solved in a previous paper by constructing a…

High Energy Astrophysical Phenomena · Physics 2016-05-10 Lee Lindblom , Nathaniel M. Indik

This paper explores hydrodynamics and hydrostatic of a star in post-Newtonian approximation of massive Bran-Dicke gravity. We study approximated solution of the field equations upto $O(c^{-4})$ and generalize Euler equation of motion. We…

General Relativity and Quantum Cosmology · Physics 2016-05-11 M. Sharif , Rubab Manzoor