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Related papers: Constraints on Perturbative f(R) Gravity via Neutr…

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We study the structure of neutron stars in R+\beta\ R^{\mu \nu} R_{\mu \nu} gravity model with perturbative method. We obtain mass--radius relations for six representative equations of state (EoSs). We find that, for |\beta| ~ 10^11 cm^2,…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Cemsinan Deliduman , K. Y. Ekşi , Vildan Keleş

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

In recent years, modified gravity theories have gained significant attention as potential replacements for the general theory of relativity. Neutron stars, which are dense compact objects, provide ideal astrophysical laboratories for…

General Relativity and Quantum Cosmology · Physics 2023-07-20 K. Nobleson , Sarmistha Banik , Tuhin Malik

Neutron star models in perturbative $f(R)$ gravity are considered with realistic equations of state. In particular, we consider the FPS, SLy and other equations of state and a case of piecewise equation of state for stars with quark cores.…

General Relativity and Quantum Cosmology · Physics 2015-06-17 Artyom V. Astashenok , Salvatore Capozziello , Sergei D. Odintsov

Modern multi-messenger astronomical observations and heavy ion experiments provide new insights into the structure of compact objects. Nevertheless, much ambiguity remains when it comes to super dense matter above the nuclear saturation…

General Relativity and Quantum Cosmology · Physics 2021-02-03 Victor I. Danchev , Daniela D. Doneva

In this work, we investigate the neutron star structure in conservative $f(R, T)$ gravity with $f(R, T)=R+\lambda T$, where $\lambda$ denotes the matter--geometry coupling. The modified stellar structure equations are solved using realistic…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-27 Premachand Mahapatra , Prasanta Kumar Das

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

The effects implied for the structure of compact objects by the modification of General Relativity produced by the generalization of the Lagrangian density to the form f(R)=R+\alpha R^2, where R is the Ricci curvature scalar, have been…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-24 Mariana Orellana , Federico García , Florencia Anabella Teppa Pannia , Gustavo Esteban Romero

Neutron stars (NSs) are thought to be excellent laboratories for determining the equation of state (EoS) of cold dense matter. Their strong gravity suggests that they can also be used to constrain gravity models. The mass and radius (M-R)…

High Energy Astrophysical Phenomena · Physics 2014-04-16 Kazim Yavuz Ekşi , Can Güngör , Murat Metehan Türkoğlu

We study the structure of neutron stars in f(R) gravity theories with perturbative constraints. We derive the modified Tolman-Oppenheimer-Volkov equations and solve them for a polytropic equation of state. We investigate the resulting…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Alan Cooney , Simon DeDeo , Dimitrios Psaltis

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 equation of state (EOS) of dense matter has been a long-sought goal of nuclear physics. Equations of state generate unique mass versus radius (M-R) relations for neutron stars, the ultra-dense remnants of stellar evolution. In this…

Nuclear Theory · Physics 2015-06-05 Andrew W. Steiner , James M. Lattimer , Edward F. Brown

In the context of f(R)=R + alpha R^2 gravity, we study the existence of neutron and quark stars with no intermediate approximations in the generalised system of Tolman-Oppenheimer-Volkov equations. Analysis shows that for positive alpha's…

General Relativity and Quantum Cosmology · Physics 2017-10-04 Artyom V. Astashenok , Alvaro de la Cruz-Dombriz , Sergei D. Odintsov

It is well known that the equation of state (EoS) of compact objects like neutron and quark stars is not determined despite there are several sophisticated models to describe it. From the electromagnetic observations, summarized in…

Taking into account the terrestrial experiments and the recent astrophysical observations of neutron stars and gravitational-wave signals, we impose restrictions on the equation of state (EoS) for isospin-asymmetric nuclear matter. Using…

Nuclear Theory · Physics 2021-03-18 Soonchul Choi , Tsuyoshi Miyatsu , Myung-Ki Cheoun , Koichi Saito

The equation of state (EoS) of neutron matter plays a decisive role to understand the neutron star properties and the gravitational waves from neutron star mergers. At sufficient densities, the appearance of hyperons generally softens the…

Nuclear Theory · Physics 2025-02-21 Hui Tong , Serdar Elhatisari , Ulf-G. Meißner

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

We investigate the behavior of curvature invariants for a large ensemble of neutron stars built with equations of state (EOSs) that satisfy constraints from nuclear theory and perturbative QCD, as well as measurements of neutron-star…

General Relativity and Quantum Cosmology · Physics 2026-04-23 Iván Garibay , Christian Ecker , Luciano Rezzolla

The determination of the equation of state (EOS) for nuclear matter has been one of the biggest problems in nuclear astrophysics, because the EOS is essential for determining the properties of neutron stars. To constrain the…

Nuclear Theory · Physics 2022-04-27 Hajime Sotani , Nobuya Nishimura , Tomoya Naito

We study the structure of neutron stars in $f(R)=R+\alpha R^{2}$ theory of gravity (Starobinsky model), in an exact and non-perturbative approach. In this model, apart from the standard General Relativistic junction conditions, two extra…

General Relativity and Quantum Cosmology · Physics 2014-05-01 Apratim Ganguly , Radouane Gannouji , Rituparno Goswami , Subharthi Ray
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