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This paper delves into the impact of extended symmetric teleparallel theory on anisotropic compact stellar structures. The explicit field equations were formulated by considering a minimum model of this extended gravity. Basically, the…

General Relativity and Quantum Cosmology · Physics 2025-05-01 M. Zeeshan Gul , M. Sharif , Adeeba Arooj , Baiju Dayanandan

Spherically symmetric relativistic stars with the polytropic equation of state, which possess the local pressure anisotropy, are considered in the context of general relativity. The modified Lane-Emden equations are derived for the special…

General Relativity and Quantum Cosmology · Physics 2018-01-25 A. A. Isayev

The Tolman VII solution (an exact static spherically symmetric perfect fluid solution) to the Einstein equations is reexamined, and a closed form equation of state (EOS) is deduced for the first time. This EOS allows further analysis…

General Relativity and Quantum Cosmology · Physics 2015-12-03 Ambrish M. Raghoonundun , David W. Hobill

This paper presents a class of exact spherical symmetric solutions of the Einstein equations admitting heat-conducting anisotropic fluid as a collapsing matter. The exterior spacetime is assumed to be the Vaidya metric. This class of…

General Relativity and Quantum Cosmology · Physics 2021-02-03 Suresh C. Jaryal

New exact interior solutions to the Einstein field equations for anisotropic spheres are found. We utilise a procedure that necessitates a choice for the energy density and the radial pressure. This class contains the constant density model…

General Relativity and Quantum Cosmology · Physics 2009-11-11 M. Chaisi , S. D. Maharaj

In this work, we explore wormhole solutions in $f(R,T)$ theory of gravity, where $R$ is the scalar curvature and $T$ is the trace of stress-energy tensor of matter. To investigate this, we consider static spherically symmetric geometry with…

General Relativity and Quantum Cosmology · Physics 2016-08-10 M. Zubair , Saira Waheed , Yasir Ahmad

We construct a family of holographic duals to anisotropic states in a strongly coupled gauge theory. On the field theory side the anisotropy is generated by giving a vacuum expectation value to a dimension three operator. We obtain our…

High Energy Physics - Theory · Physics 2020-05-20 Carlos Hoyos , Niko Jokela , José Manuel Penín , Alfonso V. Ramallo

We investigate spherically-symmetric, general relativistic systems of collapsing perfect fluid distributions. We consider neutron star models that are driven to collapse by the addition of an initially "in-going" velocity profile to the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Scott C. Noble , Matthew W. Choptuik

A simple classification is given of the anisotropic relativistic star models, resembling the one of charged isotropic solutions. On the ground of this database, and taking into account the conditions for physically realistic star models, a…

General Relativity and Quantum Cosmology · Physics 2018-01-24 B. V. Ivanov

We develop a new model for a spherically symmetric dark matter fluid sphere containing two regions: {\bf (i)} Isotropic inner region with constant density and {\bf (ii)} Anisotropic outer region. We solve the system of field equation by…

General Relativity and Quantum Cosmology · Physics 2020-12-02 Shyam Das , Nayan Sarkar , Monimala Mondal , Farook Rahaman

In this work we present full sets of solutions for rotating charged boson stars with different coupling values. By adopting local comoving coordinates, we are able to find expressions for the effective hydrodynamic quantities of the fluids…

General Relativity and Quantum Cosmology · Physics 2019-06-05 Lucas G. Collodel , Burkhard Kleihaus , Jutta Kunz

We consider an anisotropic $(p,2)$-equation, with a parametric and superlinear reaction term. We show that for all small values of the parameter the problem has at least five nontrivial smooth solutions, four with constant sign and the…

Analysis of PDEs · Mathematics 2023-04-11 Nikolaos S. Papageorgiou , Dušan D. Repovš , Calogero Vetro

In this paper we are concerned with the effects of anisotropic pressure on the boundary conditions of anisotropic Lane-Emden equation and homology theorem. Some new exact solutions of this equation are derived. Then some of the theorems…

General Relativity and Quantum Cosmology · Physics 2015-07-10 F. Shojai , M. R. Fazel , A. Estepanian , M. Kohandel

Dev (2002) discussed some exact solutions of anisotropic stars for special forms of TOV for constant energy density. Considering Bijalwan (2011) ansatz for charged perfect fluids we present here some exact solutions to the generalized TOV…

General Physics · Physics 2011-09-26 Naveen Bijalwan

We generate an explicit four-fold infinity of physically acceptable exact perfect fluid solutions of Einstein's equations by way of conformal transformations of physically unacceptable solutions (one way to view the use of isotropic…

General Relativity and Quantum Cosmology · Physics 2008-12-30 Jonathan Loranger , Kayll Lake

Stationary and axisymmetric perfect-fluid metrics are studied under the assumption of the existence of a conformal Killing vector field and in the general case of differential rotation. The possible Lie algebras for the conformal group and…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Marc Mars , Jose M. M. Senovilla

In this work, we investigate the emergence of compact, anisotropic stellar structures through the gravitational decoupling scheme within the framework of complete geometric deformation. The study introduces a novel synthesis of two…

General Relativity and Quantum Cosmology · Physics 2025-12-09 Z. Yousaf , Kazuharu Bamba , M. Z. Bhatti , S. Khan

Starting with generic stationary axially symmetric spacetimes depending on two spacelike isotropic orthogonal coordinates $x^{1}, x^{2}$, we build anisotropic fluids with and without heat flow but with wanishing viscosity. In the first part…

General Relativity and Quantum Cosmology · Physics 2018-12-31 Stefano Viaggiu

In this article, we provide a pedagogical review of the Tolman-Oppenheimer-Volkoff (TOV) equation and its solutions which describe static, spherically symmetric gaseous stars in general relativity. Our discussion starts with a systematic…

General Relativity and Quantum Cosmology · Physics 2021-06-15 Emmanuel Chavez Nambo , Olivier Sarbach

The paper considers the stationary Poisson Boolean model with spherical grains and proposes a family of nonparametric estimators for the radius distribution. These estimators are based on observed distances and radii, weighted in an…

Probability · Mathematics 2013-01-09 Daniel Hug , Günter Last , Zbyněk Pawlas , Wolfgang Weil
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