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Related papers: Polytropic stars in bootstrapped Newtonian gravity

200 papers

The so-called Buchdahl limit is not yet fully understood in the context of theories of gravity beyond the Einsteinian framework. In this investigation, we generalize this limit for the case of static, spherically-symmetric, relativistic…

General Relativity and Quantum Cosmology · Physics 2025-04-14 Raul Carpio Fernandez , Alvaro de la Cruz-Dombriz

A general formalism developed few years ago to model polytropic Newtonian stars with anisotropic pressure is applied to model stars for which, both, radial and tangential pressure satisfy polytropic equations of state. We obtain the…

General Relativity and Quantum Cosmology · Physics 2020-07-02 G. Abellan , E. Fuenmayor , L. Herrera

In this paper, the gravitational field equations for static spherically symmetric perfect fluid models with a polytropic equation of state, $p=k\rho^{1+1/n}$, are recast into two complementary 3-dimensional {\it regular} systems of ordinary…

General Relativity and Quantum Cosmology · Physics 2009-10-31 U. S. Nilsson , C. Uggla

We propose a new doorway to study the interplay between equations of state of dense matter and compact stars in gauge/gravity correspondence. For this we construct a bulk geometry near the boundary of five-dimensional spacetime. By solving…

High Energy Physics - Phenomenology · Physics 2015-06-05 Kyung Kiu Kim , Youngman Kim , Ik Jae Shin

Anisotropic stresses are ubiquitous in nature, but their modeling in General Relativity is poorly understood and frame dependent. We introduce the first study on the dynamical properties of anisotropic self-gravitating fluids in a covariant…

General Relativity and Quantum Cosmology · Physics 2019-06-05 Guilherme Raposo , Paolo Pani , Miguel Bezares , Carlos Palenzuela , Vitor Cardoso

Anisotropy is one factor that appears to be significantly important in the studies of relativistic compact stars. In this paper, we make a generalization of the Buchdahl limit by incorporating an anisotropic effect for a selected class of…

General Physics · Physics 2021-07-07 Ranjan Sharma , Arpita Ghosh , Soumik Bhattacharya , Shyam Das

We study the gravitational vacuum star (gravastar) configuration as proposed by other authors in a model where the interior de Sitter spacetime segment is continuously extended to the exterior Schwarzschild spacetime. The multilayered…

General Relativity and Quantum Cosmology · Physics 2007-06-19 A. DeBenedictis , D. Horvat , S. Ilijic , S. Kloster , K. S. Viswanathan

This is the third and final entry in a sequence of papers devoted to the formulation of a theory of self-gravitating anisotropic fluids in Newtonian gravity and general relativity. In this third paper we elevate the Newtonian theory of the…

General Relativity and Quantum Cosmology · Physics 2024-06-06 Tom Cadogan , Eric Poisson

The possible emergence of compact stars has been investigated in the recently introduced modified Gauss-Bonnet $f(\mathcal{G},T)$ gravity, where $\mathcal{G}$ is the Gauss-Bonnet term and ${T}$ is the trace of the energy-momentum tensor.…

General Relativity and Quantum Cosmology · Physics 2017-10-18 M. Farasat Shamir , Mushtaq Ahmad

We study the strong gravity regime in viable models of so-called f(R) gravity that account for the observed cosmic acceleration. In contrast with recent works suggesting that very relativistic stars might not exist in these models, we find…

General Relativity and Quantum Cosmology · Physics 2014-11-18 E. Babichev , D. Langlois

Owed to their compactness, neutron stars involve strong gravity and extreme density physics. Nevertheless, at present, there are a variety of problems where progress (at least conceptually) can be made in the context of weak gravity.…

General Relativity and Quantum Cosmology · Physics 2023-03-02 Nils Andersson , Fabian Gittins , Shanshan Yin , Rodrigo Panosso Macedo

The densities in the cores of the neutron stars (NSs) can reach several times that of the nuclear saturation density. The exact nature of matter at these densities is still virtually unknown. We consider a number of proposed,…

High Energy Astrophysical Phenomena · Physics 2024-02-16 Zenia Zuraiq , Banibrata Mukhopadhyay , Fridolin Weber

A new class of relativistic stellar structure equations which include the effects of an energy-dependent Newton coupling is presented. Significant modifications in the mass-radius relation for neutron stars are possible only if the running…

General Relativity and Quantum Cosmology · Physics 2020-01-16 Alfio Bonanno , Roberto Casadio , Alessia Platania

We investigate a compact spherically symmetric relativistic body with anisotropic particle pressure profiles. The distribution possesses characteristics relevant to modeling compact stars within the framework of general relativity. For this…

General Relativity and Quantum Cosmology · Physics 2018-02-28 S. K. Maurya , Ayan Banerjee , Sudan Hansraj

Astrophysical compact objects are studied in the context of quadratic non-metricity gravity. The solutions to the gravitational field equations, which include fluid components, are analyzed to investigate the density and pressure properties…

General Relativity and Quantum Cosmology · Physics 2025-07-24 G. G. L. Nashed , Kazuharu Bamba

This study investigates the behavior of charged compact stars within the $f(\mathfrak{Q}, \mathcal{T})$ gravitational framework, where $\mathfrak{Q}$ denotes the non-metricity scalar and $\mathcal{T}$ represents the trace of the…

General Relativity and Quantum Cosmology · Physics 2026-04-07 M. Sharif , Iqra Ibrar

We study the inertial modes of slowly rotating, fully relativistic compact stars. The equations that govern perturbations of both barotropic and non-barotropic models are discussed, but we present numerical results only for the barotropic…

General Relativity and Quantum Cosmology · Physics 2009-11-07 K. H. Lockitch , J. L. Friedman , N. Andersson

This paper is devoted to study the possibility of forming anisotropic compact stars in modified Gauss-Bonnet, namely called as $f(G)$ theory of gravity which is one of the strong candidates,responsible for the accelerated expansion of the…

General Relativity and Quantum Cosmology · Physics 2015-05-27 G. Abbas , D. Momeni , M. Aamir Ali , R. Myrzakulov , S. Qaisar

We obtain well behaved interior solutions describing hydrostatic equilibrium of anisotropic relativistic stars in scale-dependent gravity, where Newton's constant is allowed to vary with the radial coordinate throughout the star. Assuming…

General Relativity and Quantum Cosmology · Physics 2021-01-26 Grigoris Panotopoulos , Angel Rincon , Ilidio Lopes

Gravitational interferometers and cosmological observations of the cosmic microwave background offer us the prospect to probe the laws of gravity in the primordial universe. To study and interpret these datasets we need to know the possible…

High Energy Physics - Theory · Physics 2022-06-01 Giovanni Cabass , Enrico Pajer , David Stefanyszyn , Jakub Supeł