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Related papers: Neutron Stars in Scalar-tensor Gravity with Quarti…

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The masses and radii of neutron stars are discussed in general relativity and scalar-tensor theory of gravity and the differences are compared with the current uncertainties stemming from the nuclear equation of state in the relativistic…

General Relativity and Quantum Cosmology · Physics 2019-07-16 F. J. Fattoyev

We have recently developed a neutron star model fulfilling global and not local charge neutrality, both in the static and in the uniformly rotating cases. The model is described by the coupled Einstein-Maxwell-Thomas- Fermi (EMTF)…

Solar and Stellar Astrophysics · Physics 2015-06-23 Riccardo Belvedere , Jorge Armando Rueda , Remo Ruffini

In $f(R)$ gravity and Brans-Dicke theory with scalar potentials, we study the structure of neutron stars on a spherically symmetric and static background for two equations of state: SLy and FPS. In massless BD theory, the presence of a…

General Relativity and Quantum Cosmology · Physics 2019-10-04 Ryotaro Kase , Shinji Tsujikawa

We study quasi-equilibrium sequences of binary neutron stars in the framework of Damour-Esposito-Farese-type scalar-tensor theory of gravity with a massive scalar field, paying particular attention to the case where neutron stars are…

General Relativity and Quantum Cosmology · Physics 2023-09-06 Hao-Jui Kuan , Karim Van Aelst , Alan Tsz-Lok Lam , Masaru Shibata

In this work we consider an axionic scalar-tensor theory of gravity and its effects on static neutron stars. The axionic theory is considered in the regime in which the axion oscillates around its potential minimum, which cosmologically…

General Relativity and Quantum Cosmology · Physics 2024-03-18 V. K. Oikonomou

This paper investigates the structure and properties of neutron stars in four-dimensional non-polynomial gravities. Solving the modified Tolman-Oppenheimer-Volkoff equations for three different equations of state (BSk19, SLy4, AP4), we…

General Relativity and Quantum Cosmology · Physics 2025-12-30 Chen Tan , Yong-Qiang Wang

The properties of neutron stars are investigated within the relativistic central variational method by using a realistic nucleon-nucleon ($NN$) interaction. The strong repulsion of realistic $NN$ interactions at short distances is treated…

Nuclear Theory · Physics 2017-03-08 Jinniu Hu , Hong Shen , Hiroshi Toki

We investigate the stellar structure of neutron stars in the framework of Starobinsky gravity, characterized by a quadratic correction to the Einstein-Hilbert action, $f(R) = R + \alpha R^2$. In order to {\em preserve causality…

High Energy Astrophysical Phenomena · Physics 2025-08-14 Muhammed Shafeeque , Arun Mathew , Malay K. Nandy

Regarding a $d-$dimensional spherically symmetric line element in the context of Einstein-$\Lambda$ gravity, the hydrostatic equilibrium equation of stars is obtained. Then, by using the lowest order constrained variational (LOCV) method…

General Relativity and Quantum Cosmology · Physics 2017-01-30 G. H. Bordbar , S. H. Hendi , B. Eslam Panah

In this paper, we examine neutron star structure in perturbative $f(R)$ gravity models with realistic equation of state. We obtain mass-radius relations in two gravity models of the form $f_{1}(R)=R+ \alpha R(e^{-R/R_0}-1)$ and…

High Energy Astrophysical Phenomena · Physics 2021-06-22 K Nobleson , Amna Ali , Sarmistha Banik

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

Quartic gravity theory is considered with the Einstein-Hilbert Lagrangean $R+aR^{2}+bR_{\mu \nu}R^{\mu \nu},$ $R_{\mu \nu}$ being Ricci\'s tensor and R the curvature scalar. The parameters $a$ and $b$ are taken of order 1 km$^{2}.$…

General Relativity and Quantum Cosmology · Physics 2021-06-16 Emilio Santos

Ferromagnetic spin ordering can take place in neutron stars. This phase transition alters the neutron star equation of state. Here, applying the scalar-tensor theories of gravity, we investigate the structure of neutron stars which are in…

High Energy Astrophysical Phenomena · Physics 2019-03-11 Zeinab Rezaei , Habib Yousefi Dezdarani

We present a brief review of general results about non-rotating neutron stars in simple R-square gravity and its extension with a scalar axion field. Modified Einstein equations are presented for metrics in isotropical coordinates. The…

General Relativity and Quantum Cosmology · Physics 2020-07-08 Artyom V. Astashenok , Sergei D. Odintsov

In this paper, we investigate the equilibrium configurations and radial perturbations of neutron stars within a subclass of gauge-invariant Scalar-Vector-Tensor (SVT) theories. By solving the generalized Tolman-Oppenheimer-Volkoff (TOV)…

General Relativity and Quantum Cosmology · Physics 2026-05-15 Hamza Boumaza

In this paper, we investigate the structure of neutron stars by considering both the effects of the cosmological constant and the existence of quark matter for neutron stars in Einstein's gravity. For this purpose, we use a suitable…

General Physics · Physics 2022-03-02 T. Yazdizadeh , G. H. Bordbar , B. Eslam Panah

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

Nuclear matter and neutron stars are studied in the framework of an extended relativistic mean-field (RMF) model with higher-order derivative and density dependent couplings of nucleons to the meson fields. The derivative couplings lead to…

Nuclear Theory · Physics 2015-05-20 Sofija Antić , Stefan Typel

The properties of neutron star are studied in the framework of relativistic Hartree-Fock (RHF) model with realistic nucleon-nucleon ($NN$) interactions, i.e. Bonn potentials. The strong repulsion of $NN$ interaction at short range is…

Nuclear Theory · Physics 2019-10-28 Ying Zhang , Peng Liu , Jinniu Hu

We study neutron star configurations in a teleparallel gravity model featuring a scalar field coupled to both matter and torsion. In the Einstein frame, the theory includes a derivative coupling between the scalar field and the torsion…

General Relativity and Quantum Cosmology · Physics 2026-03-25 Youcef Kehal , Khireddine Nouicer