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Related papers: Neutron stars in generalized f(R) gravity

200 papers

We discuss neutron stars with strong magnetic mean fields in the framework of Extended Theories of Gravity. In particular, we take into account models derived from $f(R)$ and $f(\cal G)$ extensions of General Relativity where functions of…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Artyom V. Astashenok , Salvatore Capozziello , Sergei D. Odintsov

Within the framework of $f(R)=R+\alpha R^2$ gravity, we study realistic models of neutron stars, using equations of state compatible with the LIGO constraints. i.e. APR4, MPA1, SLy, and WW1. By numerically solving modified…

High Energy Astrophysical Phenomena · Physics 2020-02-26 Pasquale Feola , Xisco Jimenez Forteza , Salvatore Capozziello , Roberto Cianci , Stefano Vignolo

Motivated by the recent interests in spin$-2$ massive gravitons, we study the structure of neutron star in the context of massive gravity. The modifications of TOV equation in the presence of massive gravity are explored in $4$ and higher…

General Relativity and Quantum Cosmology · Physics 2017-07-25 S. H. Hendi , G. H. Bordbar , B. Eslam Panah , S. Panahiyan

We investigate in this paper the structures of neutron and quark stars in f(T) theory of gravity where T denotes the torsion scalar. Attention is attached to the TOV type equations of this theory and numerical integrations of these…

General Relativity and Quantum Cosmology · Physics 2016-11-29 A. V. Kpadonou , M. J. S. Houndjo , M. E. Rodrigues

The gravitational aether theory is a modification of general relativity that decouples vacuum energy from gravity, and thus can potentially address the cosmological constant problem. The classical theory is distinguishable from general…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-27 Farbod Kamiab , Niayesh Afshordi

Neutron stars with strong magnetic fields are considered in the framework of f(R) gravity. In order to describe dense matter in magnetic field, the model with baryon octet interacting through $\sigma$$\rho$$\omega$-fields is used. The…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Artyom V. Astashenok , Salvatore Capozziello , Sergei D. Odintsov

We formulate the equations of equilibrium of neutron stars taking into account strong, weak, electromagnetic, and gravitational interactions within the framework of general relativity. The nuclear interactions are described by the exchange…

Solar and Stellar Astrophysics · Physics 2012-06-01 Riccardo Belvedere , Daniela Pugliese , Jorge A. Rueda , Remo Ruffini , She-Sheng Xue

We study relativistic stars in the simplest model of the de Rham-Gabadadze-Tolley massive gravity which describes the massive graviton without ghost propagating mode. We consider the hydrostatic equilibrium, and obtain the modified…

General Relativity and Quantum Cosmology · Physics 2016-06-15 Taishi Katsuragawa , Shin'ichi Nojiri , Sergei D. Odintsov , Masashi Yamazaki

We investigate the global structures of neutron stars within the framework of general relativity, treating the entire star as a quantum-degenerate system. Rather than relying on the Tolman-Oppenheimer-Volkoff (TOV) equation, we solve the…

General Relativity and Quantum Cosmology · Physics 2024-12-05 Naoki Onishi

In this work we investigate neutron stars (NS) in $f(\mathtt{R,L_m})$ theory of gravity for the case $f(\mathtt{R,L_m}) = \mathtt{R} + \mathtt{L_m} + \sigma\mathtt{R}\mathtt{L_m}$, where $\mathtt{R}$ is the Ricci scalar and $\mathtt{L_m}$…

General Relativity and Quantum Cosmology · Physics 2021-11-19 R. V. Lobato , G. A. Carvalho , C. A. Bertulani

We study relativistic stars in the context of scalar tensor theories of gravity that try to account for the observed cosmic acceleration and satisfy the local gravity constraints via the chameleon mechanism. More specifically, we consider…

General Relativity and Quantum Cosmology · Physics 2015-03-13 E. Babichev , D. Langlois

Neutron stars are ideal astrophysical sources to probe general relativity due to their large compactnesses and strong gravitational fields. For example, binary pulsar and gravitational wave observations have placed stringent bounds on…

General Relativity and Quantum Cosmology · Physics 2021-08-11 Kent Yagi , Michael Stepniczka

We investigated realistic neutron stars in axion $R^{2}$ gravity. The coupling between curvature and axion field $\phi$ is assumed in the simple form $\sim R^2\phi$. For the axion mass in the range $m_{a}\sim 10^{-11}-10^{-10}$ eV the…

General Relativity and Quantum Cosmology · Physics 2020-01-29 Artyom V. Astashenok , Sergey D. Odintsov

In the present paper we investigate the structure of relativistic stars in 4D Einstein-Gauss-Bonnet gravity. The mass-radius relations are obtained for realistic hadronic and for strange quark star equations of state, and for a wide range…

General Relativity and Quantum Cosmology · Physics 2021-05-19 Daniela D. Doneva , Stoytcho S. Yazadjiev

The relativistic equations of hydrostatic equilibrium for a spherically symmetric star, or the Tolman-Oppenheimer-Volkoff equations are known in higher dimensions. In this paper, these equations have been expressed in terms of parameters of…

General Relativity and Quantum Cosmology · Physics 2020-10-21 Manjari Bagchi

Physically based changes to general relativity (GR) often predict significant differences in how spacetime behaves near massive neutron stars. One of these modifications is represented by $f(\mathcal{Q}, { \mathcal{T}})$, with $\mathcal{Q}$…

General Relativity and Quantum Cosmology · Physics 2024-10-21 G. G. L. Nashed , Tiberiu Harko

Scalar-tensor theories of gravity are natural phenomenological alternatives to General Relativity, where the gravitational interaction is mediated by a scalar degree of freedom, besides the usual tensor gravitons. In regions of the…

General Relativity and Quantum Cosmology · Physics 2013-04-29 Enrico Barausse , Carlos Palenzuela , Marcelo Ponce , Luis Lehner

We investigate the properties of the neutron star with relativistic mean field models. We incorporate in the quantum hadrodynamics and in the quark-meson coupling models a possible reduction of meson masses in nuclear matter. The equation…

Nuclear Theory · Physics 2007-05-23 C. Y. Ryu , C. H. Hyun , S. W. Hong , B. K. Jennings

The current work investigates the structural properties of neutron stars in the presence of a strong magnetic field within the framework of f(R,T) modified gravity, where the matter-geometry coupling leads to deviations from general…

General Relativity and Quantum Cosmology · Physics 2026-03-24 Charul Rathod , M. Mishra , Prasanta Kumar Das

Spherical neutron star models are studied within tensor-scalar theories of gravity. Particularly, it is shown that, under some conditions on the second derivative of the coupling function and on star's mass, for a given star there exist two…

General Relativity and Quantum Cosmology · Physics 2009-10-31 J. Novak