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Related papers: Shear-free axially symmetric dissipative fluids

200 papers

We examine the effect that the magnetic part of the Weyl tensor has on the large-scale expansion of space. This is done within the context of a class of cosmological models that contain regularly arranged discrete masses, rather than a…

General Relativity and Quantum Cosmology · Physics 2017-02-08 Timothy Clifton , Daniele Gregoris , Kjell Rosquist

We prove that aligned Petrov type D perfect fluids for which the vorticity vector is not orthogonal to the plane of repeated principal null directions and for which the magnetic part of the Weyl tensor with respect to the fluid velocity has…

General Relativity and Quantum Cosmology · Physics 2009-01-27 Norbert Van den Bergh , Lode Wylleman

A general treatment of vorticity-free, perfect fluid perturbations of Kantowski-Sachs models with a positive cosmological constant are considered within the framework of the 1+1+2 covariant decomposition of spacetime. The dynamics is…

General Relativity and Quantum Cosmology · Physics 2015-12-08 Zoltán Keresztes , Mats Forsberg , Michael Bradley , Peter K. S. Dunsby , László Á. Gergely

The full set of equations governing the structure and the evolution of self--gravitating spherically symmetric dissipative fluids with anisotropic stresses, is written down in terms of five scalar quantities obtained from the orthogonal…

General Relativity and Quantum Cosmology · Physics 2011-07-19 L. Herrera , J. Ospino , A. Di Prisco , E. Fuenmayor , O. Troconis

The axisymmetric kinematic dynamo problem is reconsidered and a number of open questions are answered. Apart from axisymmetry and smoothness of data and solution we deal with this problem under quite general conditions, i.e. we assume a…

Solar and Stellar Astrophysics · Physics 2019-09-30 Ralf Kaiser , Andreas Tilgner

We present the whole set of equations with regularity and matching conditions required for the description of physically meaningful stationary cylindrically symmmetric distributions of matter, smoothly matched to Lewis vacuum spacetime. A…

General Relativity and Quantum Cosmology · Physics 2009-11-11 F. Debbasch , L. Herrera , P. R. C. T. Pereira , N. O. Santos

In this paper, we study shearing spherically symmetric homogeneous density fluids in comoving coordinates. It is found that the expansion of the four-velocity of a perfect fluid is homogeneous, whereas its shear is generated by an arbitrary…

General Relativity and Quantum Cosmology · Physics 2016-07-29 D C Srivastava , V. C. Srivastava , Rajesh Kumar

We determine the leading order fall-off behaviour of the Weyl tensor in higher dimensional Einstein spacetimes (with and without a cosmological constant) as one approaches infinity along a congruence of null geodesics. The null congruence…

General Relativity and Quantum Cosmology · Physics 2014-11-21 Marcello Ortaggio , Alena Pravdová

We analyze asymptotic properties of higher-dimensional vacuum spacetimes admitting a "non-degenerate" geodetic multiple WAND. After imposing a fall-off condition necessary for asymptotic flatness, we determine the behaviour of the Weyl…

General Relativity and Quantum Cosmology · Physics 2009-11-15 Marcello Ortaggio , Vojtech Pravda , Alena Pravdova

This is an important and natural question as the spacetime shear, inhomogeneity and tidal effects are all intertwined via the Einstein field equations. However, as we show in this paper, such scenarios are possible for limited classes of…

General Relativity and Quantum Cosmology · Physics 2024-06-18 Jonathan Hakata , Rituparno Goswami , Chevarra Hansraj , Sunil D. Maharaj

We show that there are no new consistent cosmological perfect fluid solutions when in an open neighbourhood ${\cal U}$ of an event the fluid kinematical variables and the electric and magnetic Weyl curvature are all assumed rotationally…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Nazeem Mustapha , George F R Ellis , Henk van Elst , Mattias Marklund

We investigate the gravitational collapse of a massive scalar field in a conformally flat, spherically symmetric spacetime within general relativity. The collapsing matter distribution is modeled using a minimally coupled homogeneous scalar…

General Relativity and Quantum Cosmology · Physics 2026-05-28 Mohamed Aarif A , Soumya Chakrabarti

Recently it was shown that if the matter congruence of a general relativistic perfect fluid flow in an almost FLRW universe is shear-free, then it must be either expansion or rotation-free. Here we generalize this result for a general f(R)…

General Relativity and Quantum Cosmology · Physics 2015-03-19 Amare Abebe , Rituparno Goswami , Peter K. S. Dunsby

Space-times admitting a shear-free, irrotational, geodesic null congruence are studied. Attention is focused on those space-times in which the gravitational field is a combination of a perfect fluid and null radiation.

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. M. Sintes , A. A. Coley , D. J. McManus

We investigate the anisotropic evolution of spacetime driven by perfect fluid with off-diagonal shear-viscosity components. We consider the simplest form of the equation of state for fluid, for which the pressure and the shear stress are…

General Relativity and Quantum Cosmology · Physics 2023-12-25 Inyong Cho , Rajibul Shaikh

Spherically symmetric spacetimes are ambient spaces for models of stellar collapse and inhomogeneous cosmology. We obtain results for the Weyl tensor and the covariant form of the Ricci tensor on general doubly warped (DW) spacetimes. In a…

General Relativity and Quantum Cosmology · Physics 2022-09-08 Carlo Alberto Mantica , Luca Guido Molinari

The properties of interior spacetimes sourced by stationary cylindrical anisotropic fluids are here analytically studied for both nonrigid and rigid rotation. As regards nonrigid rotation, this is, to our knowledge, the first work dedicated…

General Relativity and Quantum Cosmology · Physics 2020-08-19 Marie-Noëlle Célérier , Nilton O. Santos

We have carried out simulations of the nonlinear evolution of the magnetohydrodynamic (MHD) Kelvin-Helmholtz (KH) instability for compressible fluids in $2\frac{1}{2}$-dimensions, extending our previous work by Frank et al (1996) and Jones…

Astrophysics · Physics 2016-08-30 Hyunju Jeong , Dongsu Ryu , T. W. Jones , Adam Frank

We consider non-rotating geodesic perfect fluid spacetimes which are purely radiative in the sense that the gravitational field satisfies the covariant transverse conditions div H = div E = 0. We show that when the shear tensor S is…

General Relativity and Quantum Cosmology · Physics 2008-11-26 H. R. Karimian , N. Van den Bergh , L. De Groote

We analyse the gravitational behaviour of a relativistic heat conducting fluid in a shear-free spherically symmetric spacetime. We show that the isotropy of pressure is a consistency condition which realises a second order nonlinear…

General Relativity and Quantum Cosmology · Physics 2015-12-31 B. P. Brassel , S. D. Maharaj , G. Govender