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Related papers: Exploration of a Singular Fluid Spacetime

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The fluid models mentioned in the title are studied in a modified approach, based on two formulas for the mass function. All characteristics of the fluid are expressed through a master potential, satisfying an ordinary second order…

General Relativity and Quantum Cosmology · Physics 2011-04-21 B. V. Ivanov

Considering the evolution of a perfect fluid with self-similarity of the second kind, we have found that an initial naked singularity can be trapped by an event horizon due to collapsing matter. The fluid moves along time-like geodesics…

General Relativity and Quantum Cosmology · Physics 2012-10-25 C. F. C. Brandt , R. Chan , M. F. A. da Silva , J. F. Villas da Rocha

We discuss the corrected thermodynamics and naked singularity structure of the topological static spherically symmetric solution in $\mathcal{F}(R,\mathcal{G})$ - gravity coupled with Born-Infeld - like nonlinear electrodynamics. Solutions…

High Energy Physics - Theory · Physics 2024-03-05 Mert Mangut , Özay Gürtuğ , İzzet Sakallı

There are a number of publications on relativistic objects dealing either with black holes or naked singularities in the center. Here we show that there exist static spherically symmetric solutions of Einstein equations with a strongly…

General Relativity and Quantum Cosmology · Physics 2024-08-27 O. S. Stashko , V. I. Zhdanov

Interior perfect fluid solutions for the Reissner-Nordstrom metric are studied on the basis of a new classification scheme. It specifies which two of the fluid's characteristics are given functions and picks up accordingly one of the three…

General Relativity and Quantum Cosmology · Physics 2007-05-23 B. V. Ivanov

Einstein's field equations in general relativity admit a variety of solutions with spacetime singularities. Numerical relativity has recently revealed the properties of somewhat generic spacetime singularities. It has been found that in a…

General Relativity and Quantum Cosmology · Physics 2009-08-18 Tomohiro Harada

We obtain an equation for the density profile in a self-gravitating polytropic spherically symmetric turbulent fluid with an equation of state $p_{\rm gas}\propto \rho^\Gamma$. This is done in the framework of ensembles of molecular clouds…

Astrophysics of Galaxies · Physics 2021-06-30 S. Donkov , I. Zh. Stefanov , T. V. Veltchev , R. S. Klessen

In this paper, we consider the Cauchy problem for pressureless gases in two space dimensions with generic smooth initial data (density and velocity). These equations give rise to singular curves, where the mass has positive density…

Analysis of PDEs · Mathematics 2023-07-24 Alberto Bressan , Geng Chen , Shoujun Huang

We adopt an effective action inspired by asymptotically safe gravity, in which the effective gravitational constant is parametrized as $G(\epsilon) = G_{N} /[1 + \tilde{\omega} (G_{N}^{2} \epsilon)^{\alpha}]$, where $G_{N}$ and $\epsilon$…

General Relativity and Quantum Cosmology · Physics 2025-06-18 Tomohiro Harada , Chiang-Mei Chen , Rituparna Mandal

We present new results concerning the existence of static, electrically charged, perfect fluid spheres that have a regular interior and are arbitrarily close to a maximally charged black-hole state. These configurations are described by…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Fernando de Felice , Liu Siming , Yu Yunqiang

We study the evolution of a perfect--fluid sphere coupled to a scalar radiation field. By ensuring a Ricci invariant regularity as a conformally flat spacetime at the central world line we find that the fluid coupled to the scalar field…

General Relativity and Quantum Cosmology · Physics 2010-05-12 W. Barreto , L. Castillo , E. Barrios

The spherically symmetric singular perfect fluid shells are considered for the case of their radii being equal to the event horizon (the black shells). We study their observable masses, depending at least on the three parameters, viz., the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Konstantin G. Zloshchastiev

We present a general solution of third order Lovelock gravity in the presence of a specific type II perfect fluid. This solution for linear equation of state, $p=w(\rho-4B)$ contains all the known solutions of third order Lovelock gravity…

General Relativity and Quantum Cosmology · Physics 2014-11-18 M. H. Dehghani , N. Farhangkhah

We obtain two equations (following from two different approaches) for the density profile in a self-gravitating polytropic cylindrically symmetric and rotating turbulent gas disk. The adopted physical picture is appropriate to describe the…

Astrophysics of Galaxies · Physics 2023-12-07 S. Donkov , I. Zh. Stefanov , T. V. Veltchev , R. S. Klessen

We study Born-Infeld gravity coupled to an anisotropic fluid in a static, spherically symmetric background. The free function characterizing the fluid is selected on the following grounds: i) recovery of the Reissner-Nordstr\"om solution of…

General Relativity and Quantum Cosmology · Physics 2017-11-22 C. Menchon , Gonzalo J. Olmo , D. Rubiera-Garcia

We provide a new class of exact solutions for the interior in (2 + 1) dimensional spacetime. The solutions obtained for the perfect fluid model both with and without cosmological constant ($\Lambda$) are found to be regular and singularity…

General Relativity and Quantum Cosmology · Physics 2014-05-02 Farook Rahaman , Piyali Bhar , Ritabrata Biswas , A. A. Usmani

Present paper provides a new model for perfect fluid sphere filled with charge in higher dimensional spacetime admitting conformal symmetry. We consider a linear equation of state with coefficients fixed by the matching conditions at the…

General Physics · Physics 2016-01-13 Piyali Bhar , Tuhina Manna , Farook Rahaman , Saibal Ray , and G. S. Khadekar

We analyze the isothermal property in static fluid spheres within the framework of the modified $f(R, T)$ theory of gravitation. The equation of pressure isotropy of the standard Einstein theory is preserved however, the energy density and…

General Relativity and Quantum Cosmology · Physics 2018-09-26 Sudan Hansraj

We have constructed a spherically symmetric structure model in a cosmological background filled with perfect fluid with non-vanishing pressure as an exact solution of Einstein equations using the Lema\^{i}tre solution. To study its local…

General Relativity and Quantum Cosmology · Physics 2015-10-07 Rahim Moradi , Javad T. Firouzjaee , Reza Mansouri

We present the conformally 1+3 Hubble-normalized field equations together with the general total source equations, and then specialize to a source that consists of perfect fluids with general barotropic equations of state. Motivating,…

General Relativity and Quantum Cosmology · Physics 2010-01-15 Patrik Sandin , Claes Uggla