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Related papers: Further stable neutron star models from f(R) gravi…

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We calculate the maximum mass of neutron stars for three different equations of state (EOS) based on generalized Skyrme functionals that are simultaneously fitted to essentially all the 2003 nuclear mass data (the rms deviation is 0.58 MeV…

Nuclear Theory · Physics 2012-12-05 N. Chamel , A. F. Fantina , J. M. Pearson , S. Goriely

There is a growing interest in investigating modified theories of gravity, primarily, with the aim of explaining the universe's accelerated expansion, which has been confirmed by several independent observations. Compact objects, like…

General Relativity and Quantum Cosmology · Physics 2021-08-16 K Nobleson , Tuhin Malik , Sarmistha Banik

Quark star models with realistic equation of state in nonperturbative $f(R)$ gravity are considered. The mass-radius relation for $f(R)=R+\alpha R^2$ model is obtained. Considering scalar curvature $R$ as an independent function, one can…

General Relativity and Quantum Cosmology · Physics 2015-06-23 A. V. Astashenok , S. Capozziello , S. D. Odintsov

In this study, we investigate strange quark stars within the framework of modified $f(R,T)$ gravity, where $R$ represents the Ricci scalar and $T$ denotes the trace of the energy-momentum tensor, specifically defined as $ f(R,T) = R + 2\chi…

General Relativity and Quantum Cosmology · Physics 2024-10-08 Suman Pal , Gargi Chaudhuri

The realistic models of neutron stars are considered for simple $R+\alpha R^2$ gravity and equivalent Brance-Dicke theory with dilaton field in Einsein frame. For negative values of $\alpha$ we have no acceptable results from astrophysical…

General Relativity and Quantum Cosmology · Physics 2018-12-27 Artyom V. Astashenok , Alexey S. Baigashov , Sergey A. Lapin

An equation of state (EoS) for symmetric nuclear matter is constructed using the density dependent M3Y effective interaction and extended for isospin asymmetric nuclear matter. Theoretically obtained values of symmetric nuclear matter…

Nuclear Theory · Physics 2014-04-23 D. N. Basu , Partha Roy Chowdhury , Abhishek Mishra

We find some exact solutions for constant-density and quark matter equations of state in stellar structure models framed within the $f(R,T)=R+\lambda \kappa^2 T$ theory of gravity, where $R$ is the curvature scalar, $T$ the trace of the…

General Relativity and Quantum Cosmology · Physics 2025-04-09 Aliya Batool , Abdul Malik Sultan , Gonzalo J. Olmo , Diego Rubiera-Garcia

Neutron stars are highly compact astrophysical objects and therefore of utmost relevance to learn about theories of gravity. Whereas the proper equation of state of the nuclear matter inside neutron stars is not yet known, and a wide range…

General Relativity and Quantum Cosmology · Physics 2022-04-28 Jutta Kunz

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

This thesis investigates compact astrophysical objects within modified theories of gravity, focusing on neutron stars and strange stars. The work studies their internal structure, equilibrium, and stability in gravitational frameworks based…

General Relativity and Quantum Cosmology · Physics 2026-05-26 Sneha Pradhan

We investigate the causal limit of maximum mass for stars in the framework of$f(R)$ gravity. We choose a causal equation of state, with variable speed of sound, and with the transition density and pressure corresponding to the SLy equation…

General Relativity and Quantum Cosmology · Physics 2021-04-07 A. V. Astashenok , S. Capozziello , S. D. Odintsov , V. K. Oikonomou

Properties of neutron stars in GW170817 are investigated using different equations of state (EoS) involving nucleons, $\Lambda$ hyperons, quarks resulting in $2M_{\odot}$ neutron stars. This calculation is performed using the same EoS for…

High Energy Astrophysical Phenomena · Physics 2019-01-02 Sajad A. Bhat , Debades Bandyopadhyay

Both fast and slow configurations of rotating neutron stars (NSs) are studied with the recently-constructed unified NS EoSs. The calculations for pure quark stars (QSs) and hybrid stars (HSs) are also done, using several updated quark…

High Energy Astrophysical Phenomena · Physics 2017-06-21 Ang Li , Jianmin Dong

We construct equilibrium configurations for neutron stars using a specific $f(R,T)$ functional form, recently derived through gaussian process applied to measurements of the Hubble parameter. By construction, this functional form serves as…

General Relativity and Quantum Cosmology · Physics 2024-11-15 J. T. Quartuccio , P. H. R. S. Moraes , G. N. Zeminiani , M. M. Lapola

A set of theoretical mass-radius relations for rigidly rotating neutron stars with exotic cores, obtained in various theories of dense matter, is reviewed. Two basic observational constraints are used: the largest measured rotation…

High Energy Astrophysical Phenomena · Physics 2016-04-20 P. Haensel , M. Bejger , M. Fortin , J. L. Zdunik

A broad sample of computed realistic equations of state of superdense matter with quark phase transition is used to construct a series of models neutron stars with a strange quark core. The integral characteristics of the stellar…

Astrophysics · Physics 2009-11-10 G. B. Alaverdyan , A. R. Harutyunyan , Yu. L. Vartanyan

Recently, an association of GW190425 and FRB 20190425A had been claimed and a highly magnetized neutron star (NS) remnant was speculated. Given the $\sim 2.5$-h delay of the occurrence of FRB 20190425A, a uniformly rotating supramassive…

High Energy Astrophysical Phenomena · Physics 2024-05-01 Shao-Peng Tang , Ming-Zhe Han , Yong-Jia Huang , Yi-Zhong Fan , Da-Ming Wei

Massive neutron stars (NS) are expected to possess a quark core. While the hadronic side of the NS equation of state (EOS) can be considered well established, the quark side is quite uncertain. While calculating the EOS of hadronic matter…

Astrophysics · Physics 2009-11-07 G. F. Burgio , M. Baldo , P. K. Sahu , A. B. Santra , H. -J. Schulze

In the present paper we investigate non-perturbatively and self-consistently the structure of neutron stars in $R$-squared gravity by simultaneously solving the interior and exterior problem. The mass-radius relations are obtained for…

General Relativity and Quantum Cosmology · Physics 2015-06-18 Stoytcho S. Yazadjiev , Daniela D. Doneva , Kostas D. Kokkotas , Kalin V. Staykov

In this study, we perform full three dimensional numerical relativity simulations of non-rotating general relativistic stars. Extending the studies for polytropic equation of state, we investigate the accuracy and robustness of numerical…

General Relativity and Quantum Cosmology · Physics 2023-06-16 Swarnim Shashank , Fatemeh Hossein Nouri , Anshu Gupta