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Related papers: Polytropic stars in bootstrapped Newtonian gravity

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Some modified theories of gravity are known to predict monopolar, in addition to the usual quadrupolar and beyond, gravitational radiation in the form of `breathing' modes. For the same reason that octupole and higher-multipole terms often…

High Energy Astrophysical Phenomena · Physics 2018-11-14 Arthur G Suvorov

Assuming static and spherically symmetric stars with perfect fluid matter, we used realistic equations of state to study neutron stars in covariant $f(Q)$ gravity. The structure profiles and properties of neutron stars such as mass, radius…

General Relativity and Quantum Cosmology · Physics 2024-09-05 Muhammad Azzam Alwan , Tomohiro Inagaki , B. Mishra , S. A. Narawade

In this work, we study the gravitational back-reaction (i.e., the "self-force") of a point mass moving around a non-rotating, compact star on a circular orbit. We find that the additional self-force, comparing with the case with a point…

General Relativity and Quantum Cosmology · Physics 2024-06-05 Xuefeng Feng , Huan Yang

The condition for pressure isotropy is reduced to a recurrence equation with variable, rational coefficients of order three. We prove that this difference equation can be solved in general. Consequently we can find an exact solution to the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 A. J. John , S. D. Maharaj

The purpose of this paper is to study charged compact stars using extended gravitational theory, also known as $f(\mathcal{R}, \mathcal{G}, \mathcal{T})$ gravity. Alternatively, this theory is also called $f(\mathcal{R}, \mathcal{T},…

General Relativity and Quantum Cosmology · Physics 2023-08-23 M. Ilyas , A. R. Athar , Asma Bibi

In this study we obtain interior solutions and investigate structural properties of isotropic compact stars in the framework of four-dimensional regularized Einstein-Gauss-Bonnet (4DEGB) gravity. For stellar matter content, we adopt a…

General Relativity and Quantum Cosmology · Physics 2026-01-21 G. Panotopoulos , Á. Rincón , I. Lopes

We present a spherically symmetric solution of the general relativistic field equations in isotropic coordinates for charged fluid with pressure anisotropy, compatible with a super dense star modeling. Further, we have constructed an…

General Physics · Physics 2015-02-12 Ksh. Newton Singh , Narendra Pradhan , Manuel Malaver

This paper aims to explore some realistic configurations of anisotropic spherical structures in the background of metric $f(R)$ gravity, where $R$ is the Ricci scalar. The solutions obtained by Krori and Barua are used to examine the nature…

General Relativity and Quantum Cosmology · Physics 2017-11-08 Z. Yousaf , M. Sharif , M. Ilyas , M. Z. Bhatti

The Schwarzschild interior solution, when combined with the assumption of a finite central pressure, leads to the well-known Buchdahl bound. This bound establishes an upper limit on the mass-to-radius ratio of an object, which is equivalent…

General Relativity and Quantum Cosmology · Physics 2026-05-25 Christian G. Boehmer , Naresh Dadhich , Surajit Das

The objective of this research is to explore compact celestial objects while considering the framework of an extended gravitational theory known as $\mathcal{R}+f(\mathcal{G})$ gravity. The notations $\mathcal{R}$ and $\mathcal{G}$ denote…

General Relativity and Quantum Cosmology · Physics 2024-07-08 G. G. L. Nashed , Kazuharu Bamba

In this article, we attempt to find a singularity free solution of Einstein's field equations for compact stellar objects, precisely strange (quark) stars, considering Schwarzschild metric as the exterior spacetime. To this end, we consider…

General Relativity and Quantum Cosmology · Physics 2017-10-19 Debabrata Deb , Sourav Roy Chowdhury , Saibal Ray , Farook Rahaman , B. K. Guha

In this paper, we generate an exact anisotropic gravastar model using gravitational decoupling technique through minimal geometric deformation in the framework of $f(\Re, {T}^{2})$ gravity. This novel model explains an ultra-compact stellar…

General Relativity and Quantum Cosmology · Physics 2023-04-17 M. Sharif , Saba Naz

Solutions to equilibrium sequences of irrotational binary polytropic stars in Newtonian gravity are expanded in a power of $\epsilon=a_0/R$, where R and $a_0$ are the orbital separation of the binary system and the radius of each star for…

Astrophysics · Physics 2009-10-31 Keisuke Taniguchi , Takashi Nakamura

Within general relativity, black holes are widely regarded as the ultimate benchmark for compactness in the Universe. Recently, however, neutron star models have been constructed in a higher-curvature theory -- quasi-topological gravity…

General Relativity and Quantum Cosmology · Physics 2026-05-20 Liang Liang , Zhe Luo , Shoulong Li , Hongwei Yu

This paper deals with the theoretical modeling of anisotropic compact stars in the framework of $f(T)$ theory of gravity, where $T$ is torsion scalar. To this end, we have used the exact solutions of Krori and Barua metric to a static…

General Physics · Physics 2016-02-16 G. Abbas , Afshan Kanwal , M. Zubair

A model for the static weak-field macroscopic medium is analyzed and the equation for the macroscopic gravitational potential is derived. This is a biharmonic equation which is a non-trivial generalization of the Poisson equation of…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Giovanni Montani , Remo Ruffini , Roustam Zalaletdinov

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 paper, we study the stellar structure in terms of alternative theory of gravity specially by f (R;T) gravity theory. Here, we consider the function f (R;T) = R+2VT where R is the Ricci scalar, T is the stress-energy momentum and V…

General Relativity and Quantum Cosmology · Physics 2021-06-24 J. Kumar , H. D. Singh , A. K. Prasad

We investigate newtonian description of accreting compact bodies with hard surfaces, including luminosity and selfgravitation of polytropic perfect fluids. This nonlinear integro-differential problem reduces, under appropriate boundary…

Astrophysics · Physics 2007-05-23 Janusz Karkowski , Edward Malec , Krzysztof Roszkowski

We propose a new numerical method to calculate irrotational binary systems composed of compressible gaseous stars in Newtonian gravity. Assuming irrotationality, i.e. vanishing of the vorticity vector everywhere in the star in the inertial…

Astrophysics · Physics 2009-10-30 Koji Uryu , Yoshiharu Eriguchi