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200 papers

Neutron stars are among the densest known objects in the universe and an ideal laboratory for the strange physics of super-condensed matter. While the simultaneously measurements of mass and radius of non-rotating neutron stars may impose…

Nuclear Theory · Physics 2020-02-03 P. S. Koliogiannis , Ch. C. Moustakidis

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

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

The recent detection of gravitational waves from merging neutron star events has opened a new window on the many unknown aspects of their internal dynamics. A key role in this context is played by the transition from baryon to quark matter…

High Energy Physics - Phenomenology · Physics 2019-10-08 Abha Rajan , Tyler Gorda , Simonetta Liuti , Kent Yagi

We investigate the neutron star (NS) equation of state (EOS) by incorporating multi-messenger data of GW170817, PSR J0030+0451, PSR J0740+6620, and state-of-the-art theoretical progresses, including the information from chiral effective…

High Energy Astrophysical Phenomena · Physics 2023-05-23 Ming-Zhe Han , Yong-Jia Huang , Shao-Peng Tang , Yi-Zhong Fan

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

We have computed the properties of compact objects like neutron stars based on equation of state (EOS) deduced from a core-envelope model of superdense stars. Such superdense stars have been studied by solving the Einstein's equation based…

General Relativity and Quantum Cosmology · Physics 2026-05-05 A. C. Khunt , V. O. Thomas , P. C. Vinodkumar

Probing gravity in its strongest regime is a central goal of modern physics, as the nature of the most compact objects reflects fundamental aspects of Einstein's theory of general relativity (GR). In GR, black holes are regarded as the most…

General Relativity and Quantum Cosmology · Physics 2026-05-20 Shoulong Li , H. Lü , Yong Gao , Rui Xu , Lijing Shao , Hongwei Yu

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

There are many ways to probe alternative theories of gravity, namely, via: experimental tests at solar system scale, cosmological data and models, gravitational waves and compact objects. In the present paper we consider a model of gravity…

General Relativity and Quantum Cosmology · Physics 2022-11-08 José C. N. de Araujo , Hemily G. M. Fortes

Pulsars are among the most mysterious astrophysical objects in the Universe and are believed to be rotating neutron stars formed in supernova explosions. They are unique testing grounds of dense matter theories and gravitational physics and…

Solar and Stellar Astrophysics · Physics 2010-01-06 Plamen G. Krastev , Bao-An Li

Given an Equation of State (EOS) for neutron star (NS) matter, there is a unique mass-radius sequence characterized by a maximum mass $M_{\rm{NS}}^{\max}$ at radius $R_{\max}$. We first show analytically that the $M_{\rm{NS}}^{\max}$ and…

Nuclear Theory · Physics 2023-07-27 Bao-Jun Cai , Bao-An Li , Zhen Zhang

Two distinct non-singular interior models that describe anisotropic spherical configurations are presented in this work. We develop the Einstein field equations and the associated mass function in accordance with a static spherical…

General Relativity and Quantum Cosmology · Physics 2025-10-10 M. Sharif , Tayyab Naseer , Hira Shadab

In this work we present general predictions for the static observables of neutron stars (NSs) under the hypothesis of a purely nucleonic composition of the ultra-dense baryonic matter, using Bayesian inference on a very large parameter…

Nuclear Theory · Physics 2024-02-28 Luigi Scurto , Helena Pais , Francesca Gulminelli

Neutron stars, produced at the death of massive stars, are often regarded as giant neutron-rich nuclei. This picture is especially relevant for low-mass (below about solar mass) neutron stars, where non-nucleonic components are not expected…

High Energy Astrophysical Phenomena · Physics 2014-05-08 Hajime Sotani , Kei Iida , Kazuhiro Oyamatsu , Akira Ohnishi

The maximum mass of a nonrotating neutron star, $M_{\rm TOV}$, plays a very important role in deciphering the structure and composition of neutron stars and in revealing the equation of state (EOS) of nuclear matter. Although with a…

High Energy Astrophysical Phenomena · Physics 2023-01-04 Christian Ecker , Luciano Rezzolla

Neutron stars -- compact objects with masses similar to that of our Sun but radii comparable to the size of a city -- contain the densest form of matter in the universe that can be probed in terrestrial laboratories as well as in earth- and…

Nuclear Theory · Physics 2022-10-06 J. Piekarewicz

Neutron star is the ultimate testing place for the physics of dense nuclear matter. Before the detection of gravitational waves from the merger of binary neutron stars, various nuclear equations of state have been used to estimate the…

Nuclear Theory · Physics 2020-06-03 Young-Min Kim , Kyujin Kwak , Chang Ho Hyun , Hana Gil , Chang-Hwan Lee

We search for possible correlations between neutron star observables and thermodynamic quantities that characterize high density nuclear matter. We generate a set of model-independent equations of state describing stellar matter from a…

Nuclear Theory · Physics 2020-03-04 Márcio Ferreira , M. Fortin , Tuhin Malik , B. K. Agrawal , Constança Providência

The Bethe-Brueckner-Goldstone many-body theory of the Nuclear Equation of State is reviewed in some details. In the theory, one performs an expansion in terms of the Brueckner two-body scattering matrix and an ordering of the corresponding…

Nuclear Theory · Physics 2007-05-23 Marcello Baldo , Fiorella Burgio