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We set up the construction of generic (d+2)-dimensional metrics corresponding to (d+1)-dimensional fluids, representing holographically the hydrodynamic regimes of the putative dual theories. We give general seed equilibrium metrics…

High Energy Physics - Theory · Physics 2015-02-04 Natalia Pinzani-Fokeeva , Marika Taylor

We consider anisotropic fluids with directional pressures $p_i = w_i \rho$ ($\rho$ is the density, $w_i = $const, $i = 1,2,3$) as sources of gravity in stationary cylindrically symmetric space-times. We describe a general way of obtaining…

General Relativity and Quantum Cosmology · Physics 2019-06-19 S. V. Bolokhov , K. A. Bronnikov , M. V. Skvortsova

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

We examine homogeneous but anisotropic cosmologies in scalar-tensor gravity theories, including Brans-Dicke gravity. We present a method for deriving solutions for any isotropic perfect fluid with a barotropic equation of state…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Jose P. Mimoso , David Wands

An algorithm recently presented by Lake to obtain all static spherically symmetric perfect fluid solutions, is extended to the case of locally anisotropic fluids (principal stresses unequal). As expected, the new formalism requires the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 L. Herrera , J. Ospino , A. Di Prisco

We show the first simple, systematic and direct approach to decoupling gravitational sources in general relativity. As a direct application, a robust and simple way to generate anisotropic solutions for self-gravitating systems from perfect…

General Relativity and Quantum Cosmology · Physics 2017-05-24 Jorge Ovalle

In the present article we have obtained new set of exact solutions of Einstein field equations for anisotropic fluid spheres by using the Herrera et al.[1] algorithm. The anisotropic fluid solution so obtained join continuously to…

General Relativity and Quantum Cosmology · Physics 2015-09-30 S. K. Maurya , Y. K. Gupta , M. K. Jasim

We set up in detail the general formalism to model polytropic general relativistic stars with anisotropic pressure. We shall consider two different possible polytropic equations, all of which yield the same Lane-Emden equation in the…

General Relativity and Quantum Cosmology · Physics 2015-06-17 L. Herrera , W. Barreto

When solving the equations of General Relativity in a symmetric sector, it is natural to consider the same symmetry for the geometry and stress-energy. This implies that for static and isotropic spacetimes, the most general natural…

General Relativity and Quantum Cosmology · Physics 2015-05-14 Tomasz Konopka

The 4-dimensionally covariant approach to multiconstituent Newtonian fluid dynamics presented in the preceding article of this series is developed by construction of the relevant 4-dimensional stress energy tensor whose conservation in the…

Astrophysics · Physics 2009-11-10 Brandon Carter , Nicolas Chamel

In this paper Einstein's field equations, for static spherically symmetric perfect fluid models with a linear barotropic equation of state, are recast into a 3-dimensional regular system of ordinary differential equations on a compact state…

General Relativity and Quantum Cosmology · Physics 2009-10-31 U. S. Nilsson , C. Uggla

The coupled system of the spherically symmetric Einstein--Maxwell differential equations is solved under two different source conditions: non-zero electric charge and pressure anisotropy. Expressions for the metric functions, and pressures…

General Relativity and Quantum Cosmology · Physics 2016-03-11 Ambrish M. Raghoonundun , David W. Hobill

The relativistic extension of the classic stellar structure equations is investigated. It is pointed out that the Tolman-Oppenheimer-Volkov (TOV) equation with the gradient equation for local gravitational mass can be made complete as a…

General Relativity and Quantum Cosmology · Physics 2023-08-22 Shuichi Yokoyama

We present a covariant description of non-vacuum static spherically symmetric spacetimes in $f(R)$ gravity applying the (1+1+2) covariant formalism. The propagation equations are then used to derive a covariant and dimensionless form of the…

General Relativity and Quantum Cosmology · Physics 2025-04-07 Mariam Campbell , Sante Carloni , Peter K. S. Dunsby , Nolene F. Naidu

A multidimensional cosmological model describing the dynamics of n+1 Ricci-flat factor-spaces M_i in the presence of a one-component anisotropic fluid is considered. The pressures in all spaces are proportional to the density: p_i = w_i…

General Relativity and Quantum Cosmology · Physics 2008-11-26 J. -M. Alimi , V. D. Ivashchuk , S. A. Kononogov , V. N. Melnikov

This paper is the second in a sequence of three devoted to the formulation of a theory of self-gravitating anisotropic fluids in both Newtonian gravity and general relativity. In this second paper we develop the Newtonian theory, inspired…

General Relativity and Quantum Cosmology · Physics 2024-06-06 Tom Cadogan , Eric Poisson

We introduce new tetrads that manifestly and covariantly diagonalize the stress-energy tensor for a perfect fluid with vorticity at every spacetime point. This new tetrad can be applied and introduce simplification in the analysis of…

General Relativity and Quantum Cosmology · Physics 2025-10-28 Alcides Garat

In this paper we have obtained cosmological models for the static spherically symmetric spacetime with charged anisotropic fluid distribution in (n+2)-dimensions in context of Rosen's Bimetric General Relativity (BGR). An exact solution is…

General Physics · Physics 2017-05-12 A. H. Hasmani , D. N. Pandya

Using the gravitational decoupling by the minimal geometric deformation approach, we build an anisotropic version of the well-known Tolman VII solution, determining an exact and physically acceptable interior two-fluid solution that can…

General Relativity and Quantum Cosmology · Physics 2019-10-23 Sudipta Hensh , Zdeněk Stuchlík

This article is the second in a series devoted to the study of spacetimes sourced by a stationary cylinder of fluid rigidly rotating around its symmetry axis and exhibiting an anisotropic pressure by using new exact interior solutions of…

General Relativity and Quantum Cosmology · Physics 2023-08-08 Marie-No\''elle Célérier