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Related papers: Post-Newtonian expansions for perfect fluids

200 papers

The general form of the anisotropy parameter of the expansion for Bianchi type-III metric is obtained in the presence of a single diagonal imperfect fluid with a dynamically anisotropic equation of state parameter and a dynamical energy…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Ozgur Akarsu , Can B. Kilinc

Tai-Ping Liu \cite{Liu\_JJ} introduced the notion of "physical solution' of the isentropic Euler system when the gas is surrounded by vacuum. This notion can be interpreted by saying that the front is driven by a force resulting from a…

Analysis of PDEs · Mathematics 2015-04-08 Denis Serre

The symmetries of the general Euler equations of fluid dynamics with polytropic exponent are determined using the Kaluza-Klein type framework of Duval et $\it{al}$. In the standard polytropic case the recent results of O'Raifeartaigh and…

High Energy Physics - Theory · Physics 2016-08-15 M. Hassaïne , P. A. Horváthy

By a semi-Lagrangian change of coordinates, the hydrostatic Euler equations describing free-surface sheared flows is rewritten as a system of quasilinear equations, where stability conditions can be determined by the analysis of its…

We consider a self-gravitating collisionless gas as described by the Vlasov-Poisson or Einstein-Vlasov system or a self-gravitating fluid ball as described by the Euler-Poisson or Einstein-Euler system. We give a simple proof for the finite…

General Relativity and Quantum Cosmology · Physics 2013-12-16 Tobias Ramming , Gerhard Rein

We study the limiting behavior of the solutions of Euler equations of one-dimensional compressible fluid flow as the pressure like term vanishes. This system can be thought of as an approximation for the one dimensional model for large…

Analysis of PDEs · Mathematics 2018-03-06 Manas Ranjan Sahoo , Abhrojyoti Sen

The aim of this work is to study the Navier-Stokes-Voigt equations that govern flows with non-negative density of incompressible fluids with elastic properties. For the associated non-linear initial-and boundary-value problem, we prove the…

Analysis of PDEs · Mathematics 2023-09-04 Hermenegildo Borges de Oliveira , Khonatbek Khompysh , Aidos Ganizhanuly Shakir

Vlasov equations can be formally derived from N-body dynamics in the mean-field limit. In some suitable singular limits, they may themselves converge to fluid dynamics equations. Motivated by this heuristic, we introduce natural scalings…

Analysis of PDEs · Mathematics 2020-08-27 Daniel Han-Kwan , Mikaela Iacobelli

We consider the motion of the interface separating a vacuum from an inviscid, incompressible, and irrotational fluid, subject to the self-gravitational force and neglecting surface tension, in two space dimensions. The fluid motion is…

Analysis of PDEs · Mathematics 2015-11-04 Lydia Bieri , Shuang Miao , Sohrab Shahshahani , Sijue Wu

The Einstein equations for a perfect fluid spatially homogeneous spacetime are studied in a unified manner by retaining the generality of certain parameters whose discrete values correspond to the various Bianchi types of spatial…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Robert T. Jantzen

We prove that in the infinite speed-of-light limit (i.e., non-relativistic and subhorizon limits), the relativistic fully nonlinear cosmological perturbation equations in two gauge conditions, the zero-shear gauge and the uniform-expansion…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Jai-chan Hwang , Hyerim Noh

The non-equilibrium contributions to the post-Newtonian hydrodynamic equations are determined from a relaxation-time model of the post-Newtonian Boltzmann equation. The Chapman-Enskog method is used to calculate the non-equilibrium…

General Relativity and Quantum Cosmology · Physics 2023-04-05 Gilberto M. Kremer

We study the Einstein field equations for spacetimes admitting a maximal two-dimensional abelian group of isometries acting orthogonally transitively on spacelike surfaces and, in addition, with at least one conformal Killing vector. The…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Marc Mars , Thomas Wolf

In this paper we utilize symmetries in order to exhibit exact solutions to Einstein's equation of a perfect fluid on a static manifold all of whose spatial factor belongs to the conformal class of a Riemannian space of constant curvature.

Differential Geometry · Mathematics 2019-05-02 Marcelo Barboza , Willian Tokura , Levi Adriano

The conformal Einstein equations for a tracefree (radiation) perfect fluid are derived in terms of the Levi-Civita connection of a conformally rescaled metric. These equations are used to provide a non-linear stability result for de…

General Relativity and Quantum Cosmology · Physics 2015-06-03 C. Lübbe , J. A. Valiente Kroon

We study a free boundary problem which is motivated by a particular case of the flow of a non-Newtonian fluid, with a pressure depending yield stress given by a Drucker-Prager plasticity criterion. We focus on the steady case and…

Analysis of PDEs · Mathematics 2017-01-19 Eleftherios Ntovoris , M Regis

The properties of LRS class II perfect fluid space-times are analyzed using the description of geometries in terms of the Riemann tensor and a finite number of its covariant derivatives. In this manner it is straightforward to obtain the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 M. Marklund , M. Bradley

The two-dimensional (2-D) Euler equations of a perfect fluid possess a beautiful geometric description: they are reduced geodesic equations on the infinite-dimensional Lie group of symplectomorphims with respect to a right-invariant…

Analysis of PDEs · Mathematics 2024-11-27 Klas Modin , Manolis Perrot

Experimental particle spectra can be successfully described by power-law tailed energy distributions characteristic to canonical equilibrium distributions associated to R\'enyi's or Tsallis' entropy formula - over a wide range of energies,…

Nuclear Theory · Physics 2013-06-27 T. S. Biró , E. Molnár

Non-equilibrium fluid dynamics derived from the extended irreversible thermodynamics of the causal M\"uller--Israel--Stewart theory of dissipative processes in relativistic fluids based on Grad's moment method is applied to the study of the…

Nuclear Theory · Physics 2008-11-26 Azwinndini Muronga