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Related papers: Polytropic stars in bootstrapped Newtonian gravity

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In the supercritical range of the polytropic indices $\gamma\in(1,\frac43)$ we show the existence of smooth radially symmetric self-similar solutions to the gravitational Euler-Poisson system. These solutions exhibit gravitational collapse…

Analysis of PDEs · Mathematics 2022-11-30 Yan Guo , Mahir Hadzic , Juhi Jang , Matthew Schrecker

We present an anisotropic charged analogue of Kuchowicz (1971) solution of the general relativistic field equations in curvature coordinates by using simple form of electric intensity $E$ and pressure anisotropy factor $\Delta$ that involve…

General Relativity and Quantum Cosmology · Physics 2020-07-15 K N Singh , F Rahaman , N Pradhan , N Pant

With regard to the coupling constant and the strong magnetic field of neutron stars, we have studied these stars in the 4D Einstein Gauss Bonnet (4D EGB) gravity model in order to grasp a better understanding of these objects. In this…

General Relativity and Quantum Cosmology · Physics 2024-02-23 Gholam Hossein Bordbar , Mohammad Mazhari , Ahmad Poostforush

We analyze the dynamics of a gravitational bounded cloud of generic bosons or a boson star in the non-relativistic regime, assuming from the very beginning that the boson star is in a Bose-Einstein condensed state. Also, we have taken into…

General Relativity and Quantum Cosmology · Physics 2024-11-05 Jorge Mastache , Elías Castellanos , Guillermo Chacón-Acosta

A new model of anisotropic compact star is obtained in our present paper by assuming the pressure anisotropy. The proposed model is singularity free. The model is obtained by considering a physically reasonable choice for the metric…

General Relativity and Quantum Cosmology · Physics 2021-07-08 Piyali Bhar , Pramit Rej

In this research, we introduce magnetically charged stars in the framework of non-singular metric which is explained with nonlinear electrodynamics(NED). This model allows us to have an upper limit for the maximum limit for the mass of…

General Relativity and Quantum Cosmology · Physics 2024-06-10 Khashayar Kianfar

The main aim of this study is to examine the behaviour of physical parameters of an anisotropic compact star model demonstrating spherical symmetry in F(Q) modified gravity. To evaluate the behaviour and the stability of an anisotropic…

General Relativity and Quantum Cosmology · Physics 2025-05-26 Sat Paul , Jitendra Kumar , S. K. Maurya

Neutron stars are highly compact astrophysical objects and therefore of utmost relevance to learn about theories of gravity. Whereas the proper equation of state of the nuclear matter inside neutron stars is not yet known, and a wide range…

General Relativity and Quantum Cosmology · Physics 2022-04-28 Jutta Kunz

A model of compact object coupled to inhomogeneous anisotropic dark energy is studied. It is assumed a variable dark energy that suffers a phase transition at a critical density. The anisotropic Lambda-Tolman-Oppenheimer-Volkoff equations…

General Relativity and Quantum Cosmology · Physics 2011-05-12 Cristian R. Ghezzi

One of the very small number of serious alternatives to the usual concept of an astrophysical black hole is the "gravastar" model developed by Mazur and Mottola; and a related phase-transition model due to Laughlin et al. We consider a…

General Relativity and Quantum Cosmology · Physics 2009-04-17 Celine Cattoen , Tristan Faber , Matt Visser

Recently the small value of the cosmological constant and its ability to accelerate the expansion of the Universe is of great interest. We discuss the possibility of forming of anisotropic compact stars from this cosmological constant as…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Sk. Monowar Hossein , Farook Rahaman , Jayanta Naskar , Mehedi Kalam , Saibal Ray

Light scalar fields can form gravitationally bound compact objects called boson stars. The profile of boson stars in the Newtonian limit is described by the Gross-Pitaevskii-Poisson equations. We present a semi-analytic solution to these…

High Energy Physics - Theory · Physics 2018-01-12 Felix Kling , Arvind Rajaraman

In this paper we study the isotropic cases of static charged fluid spheres in general relativity. For this purpose we consider two different specialization and under these we solve the Einstein-Maxwell field equations in isotropic…

General Relativity and Quantum Cosmology · Physics 2011-08-25 Basanti Das , Pratap Chandra Ray , Irina Radinschi , Farook Rahaman , Saibal Ray

We have proposed a model for relativistic compact star with anisotropy and analytically obtained exact spherically symmetric solutions describing the interior of the dense star admitting non-static conformal symmetry. Several features of…

General Relativity and Quantum Cosmology · Physics 2016-04-27 Dibyendu Shee , Farook Rahaman , B. K. Guha , Saibal Ray

This paper is devoted to discuss compact stars in $f(\mathscr{R},\mathscr{G})$ gravity, where $\mathscr{R}$ and $\mathscr{G}$ denote the Ricci scalar and Gauss-Bonnet invariant respectively. To meet this aim, we consider spherically…

General Relativity and Quantum Cosmology · Physics 2020-05-11 G. Mustafa , M. Farasat Shamir , Xia Tie-Cheng

We present the results of a numerical study of the fluid $f$, $p$ and the gravitational $w$ modes for increasingly relativistic nonrotating polytropes. The results for $f$ and $w$-modes are in good agreement with previous data for uniform…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Nils Andersson , Kostas D. Kokkotas

We study a class of Newtonian models for the deformations of non-magnetized neutron stars during their spin-down. The models have all an analytical solution, and thus allow to understand easily the dependence of the strain on the star's…

High Energy Astrophysical Phenomena · Physics 2020-10-26 Elia Giliberti , Marco Antonelli , Gabriele Cambiotti , Pierre Pizzochero

A strong candidate for a source of gravitational waves is a highly magnetised, rapidly rotating neutron star (magnetar) deformed by internal magnetic stresses. We calculate the mass quadrupole moment by perturbing a zeroth-order hydrostatic…

High Energy Astrophysical Phenomena · Physics 2011-10-25 Alpha Mastrano , Andrew Melatos , Andreas Reisenegger , Taner Akgün

We use gravitational wave (GW) and electromagnetic (EM) observations of GW170817 to constrain the extent of pressure anisotropy in it. While it is quite likely that the pressure inside a neutron star is mostly isotropic, certain physical…

General Relativity and Quantum Cosmology · Physics 2019-05-08 Bhaskar Biswas , Sukanta Bose

We review the problem of describing the gravitational field of compact stars in general relativity. We focus on the deviations from spherical symmetry which are expected to be due to rotation and to the natural deformations of mass…

General Relativity and Quantum Cosmology · Physics 2016-07-01 Hernando Quevedo