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This study investigates the modeling of anisotropic magnetized static neutron stars within the framework of five-dimensional Einstein-Gauss-Bonnet (5D EGB) gravity. While Einstein's gravity has traditionally been employed to examine neutron…

General Relativity and Quantum Cosmology · Physics 2025-08-21 Mohammad Mazhari

?In this work, we study the orbital stability of stationary solutions to the relativistic Vlasov-Manev system. This system is a kinetic model describing the evolution of a stellar system subject to its own gravity with some relativistic…

Analysis of PDEs · Mathematics 2013-03-26 Cyril Rigault

We generalise the covariant Tolman-Oppenheimer-Volkoff equations proposed in arXiv:1709.02818 [gr-qc] to the case of static and spherically symmetric spacetimes with anisotropic sources. The extended equations allow a detailed analysis of…

General Relativity and Quantum Cosmology · Physics 2018-06-27 Sante Carloni , Daniele Vernieri

As an alternative gravity model we consider an extended Einstein-Maxwell gravity containing a gauge invariance property. Extension is assumed to be addition of a directional coupling between spatial electromagnetic fields with the Ricci…

General Relativity and Quantum Cosmology · Physics 2024-01-08 Hossein Ghaffarnejad , Leyla Naderi

We investigate anisotropic and homogeneous cosmological models in the scalar-tensor theory of gravity with non-minimal kinetic coupling of a scalar field to the curvature given by the function $\eta\cdot(\phi/2)\cdot G_{\mu\nu}\,\nabla^\mu…

General Relativity and Quantum Cosmology · Physics 2025-05-13 Ruslan K. Muharlyamov , Tatiana N. Pankratyeva , Shehabaldeen O. A. Bashir

We present an anisotropic cosmological model based on a new exact solution of Einstein equations. The matter content consists of an anisotropic scalar field minimally coupled to gravity and of two isotropic perfect fluids that represent…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Saulo Carneiro , Guillermo A. Mena Marugan

The novel proposal to invoke the split of the Ricci scalar into bulk and boundary terms in the gravitational action, opens up a new avenue of investigation into stellar dynamics. The Lagrangian contains functional forms of the bulk term…

General Relativity and Quantum Cosmology · Physics 2026-05-14 Sudan Hansraj , Christian G. Boehmer , Ndumiso Buthelezi

The condition for pressure isotropy, for spherically symmetric gravitational fields with charged and uncharged matter, is reduced to a recurrence equation with variable, rational coefficients. This difference equation is solved in general…

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

The field equations of modified gravity theories, when considering a homogeneous and isotropic cosmological model, always become autonomous differential equations. This relies on the fact that in such models all variables only depend on…

General Relativity and Quantum Cosmology · Physics 2023-02-03 Christian G. Boehmer , Erik Jensko , Ruth Lazkoz

Isotropic cosmological singularities are singularities which can be removed by rescaling the metric. In some cases already studied (gr-qc/9903008, gr-qc/9903009, gr-qc/9903018) existence and uniqueness of cosmological models with data at…

General Relativity and Quantum Cosmology · Physics 2017-08-23 K. P. Tod

We study a class of inhomogeneous and anisotropic $G_2$ string cosmological models. In the case of separable $G_2$ models we show that the governing equations reduce to a system of ordinary differential equations. We focus on a class of…

High Energy Physics - Theory · Physics 2014-11-18 Alan A. Coley , R. J. van den Hoogen

We derive a Tolman-Oppenheimer-Volkoff equation in neutron star systems within the modified $f(T, \mathcal{T})$-gravity class of models using a perturbative approach. In our approach $f(T, \mathcal{T})$-gravity is considered to be a static…

General Relativity and Quantum Cosmology · Physics 2017-05-08 Mark Pace , Jackson Levi Said

In this article we try to present spherically symmetric isotropic strange star model under the framework of $f(R,\mathcal{T})$ theory of gravity. To this end, we consider that the Lagrangian density is an arbitrary linear function of the…

General Relativity and Quantum Cosmology · Physics 2018-04-23 Debabrata Deb , Farook Rahaman , Saibal Ray , B. K. Guha

This paper constructs three different anisotropic extensions of the existing isotropic solution to the modified field equations through the gravitational decoupling in $f(\mathbb{R},\mathbb{T})$ theory. For this, we take a static sphere…

General Relativity and Quantum Cosmology · Physics 2024-08-02 Tayyab Naseer , M. Sharif

We present new models of the evolution and dissolution of star clusters evolving under the combined influence of internal relaxation and external tidal fields, using the anisotropic gaseous model based on the Fokker-Planck approximation,…

Astrophysics · Physics 2009-11-10 R. Spurzem , M. Giersz , K. Takahashi , A. Ernst

This paper formulates some new exact solutions to the field equations by means of minimal gravitational decoupling in the context of $f(\mathbb{R},\mathbb{T})$ gravity. For this purpose, we consider anisotropic spherical matter distribution…

General Relativity and Quantum Cosmology · Physics 2022-12-14 M. Sharif , Tayyab Naseer

This paper is devoted to evaluating exact anisotropic spherical solutions for static self-gravitating systems through extended geometric deformation decoupling technique. For this purpose, we consider an isotropic Tolman IV solution and…

General Relativity and Quantum Cosmology · Physics 2020-04-22 M. Sharif , Qanitah Ama-Tul-Mughani

In this work, we have adopted gravitational decoupling by Minimal Geometric Deformation (MGD) approach and have developed an anisotropic version of well-known Tolman VII isotropic solution in the framework of $f(R, T)$ gravity, where $R$ is…

General Relativity and Quantum Cosmology · Physics 2021-06-17 Hina Azmat , M. Zubair

We study the gravitational collapse of a spherically symmetric anisotropic relativistic star within Einstein theory of gravity making use of one of our recently developed collapsing stellar models [{\it Astrophys. Space Sci.} {\bf361} 99…

General Relativity and Quantum Cosmology · Physics 2022-01-05 Shyam Das , Bikash Chandra Paul , Ranjan Sharma

We study superdense relativistic stars with anisotropic matter distributions with spheroidal spatial hypersurfaces. We propose a methodology to make an anisotropic generalization of the Vaidya-Tikekar superdense star model. The anisotropic…

General Relativity and Quantum Cosmology · Physics 2020-06-23 S. Thirukkanesh , Ranjan Sharma , Sunil D. Maharaj