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Related papers: Newtonian and relativistic polytropes

200 papers

Neutron star properties, such as its mass, radius, and moment of inertia, are calculated by solving the Tolman-Oppenheimer-Volkov (TOV) equations using the ring-diagram equation of state (EOS) obtained from realistic low-momentum NN…

Nuclear Theory · Physics 2009-12-31 Huan Dong , T. T. S. Kuo , R. Machleidt

Astrophysical observations of neutron stars probe the structure of dense nuclear matter and have the potential to reveal phase transitions at high densities. Most recent analyses are based on parametrized models of the equation of state…

High Energy Astrophysical Phenomena · Physics 2025-05-13 Reed Essick , Isaac Legred , Katerina Chatziioannou , Sophia Han , Philippe Landry

We present a physics-informed Bayesian neural-network framework to infer neutron-star equations of state from theoretical priors and to propagate the associated uncertainties to stellar observables. Trained on a large and representative…

High Energy Astrophysical Phenomena · Physics 2026-04-29 J. D. Baker , C. A. Bertulani , R. V. Lobato

In recent years, a lot of work was done that has revealed some very interesting properties of neutron stars. One can relate the first few multipole moments of a neutron star, or quantities that can be derived from them, with relations that…

High Energy Astrophysical Phenomena · Physics 2015-11-03 George Pappas

We consider static neutron stars within the framework of $R^2$ gravity. The neutron fluid is described by three different types of realistic equations of state (soft, moderately stiff, and stiff). Using the observational data on the neutron…

General Relativity and Quantum Cosmology · Physics 2018-06-08 Vladimir Folomeev

We review a variety of theoretical and experimental investigations aimed at improving our knowledge of the nuclear matter equation of state. Of particular interest are nuclear matter extreme states in terms of density and/or isospin…

Nuclear Theory · Physics 2015-05-18 Francesca Sammarruca

Motivated by a recent astrophysical measurement of the pressure of cold matter above nuclear-matter saturation density, we compute the equation of state of neutron star matter using accurately calibrated relativistic models. The uniform…

Nuclear Theory · Physics 2014-11-20 F. J. Fattoyev , J. Piekarewicz

We report neutron star predictions based on our most recent equations of state. These are derived from chiral effective field theory, which allows for a systematic development of nuclear forces, order by order. We utilize high-quality…

Nuclear Theory · Physics 2022-03-01 Francesca Sammarruca , Randy Millerson

The interiors of neutron stars reach densities and temperatures beyond the limits of terrestrial experiments, providing vital laboratories for probing nuclear physics. While the star's interior is not directly observable, its pressure and…

High Energy Astrophysical Phenomena · Physics 2024-02-13 Delaney Farrell , Pierre Baldi , Jordan Ott , Aishik Ghosh , Andrew W. Steiner , Atharva Kavitkar , Lee Lindblom , Daniel Whiteson , Fridolin Weber

We have recently developed a set of equations of state based on the nuclear energy density functional theory providing a unified description of the different regions constituting the interior of neutron stars and magnetars. The nuclear…

Compact objects are the name used to classify the following objects: white dwarf, neutron star and black holes. In addition to them, some authors have suggested that in the core of a neutron star we may have the quarks u,d,s and c. In this…

Neutron stars are commonly considered as astronomical objects having highdensity interiors and an inner core region in which various hadronic matter phases are expected. Several studies show that the inner structures affect macroscopic…

High Energy Astrophysical Phenomena · Physics 2016-06-22 Tomoki Endo

We study the strong gravity regime in viable models of so-called f(R) gravity that account for the observed cosmic acceleration. In contrast with recent works suggesting that very relativistic stars might not exist in these models, we find…

General Relativity and Quantum Cosmology · Physics 2014-11-18 E. Babichev , D. Langlois

Over the past decade, an abundance of information from neutron-star observations, nuclear experiments and theory has transformed our efforts to elucidate the properties of dense matter. However, at high densities relevant to the cores of…

High Energy Astrophysical Phenomena · Physics 2025-10-10 Sunny Ng , Isaac Legred , Lami Suleiman , Philippe Landry , Lyla Traylor , Jocelyn Read

This paper employs the backward ray tracing method to study the optical images of neutron stars under the conditions of a spherical light source and a thin accretion disk, considering a polynomial equation of state given by $p = K \rho^{1 +…

General Relativity and Quantum Cosmology · Physics 2026-01-13 Chen-Yu Yang , Xiao-Xiong Zeng

We investigate static spherically symmetric perfect fluid models in Newtonian gravity for barotropic equations of state that are asymptotically polytropic at low and high pressures. This is done by casting the equations into a 3-dimensional…

Astrophysics · Physics 2009-11-07 J. Mark Heinzle , Claes Uggla

Besides their astrophysical interest, compact stars also provide an arena for understanding the properties of theories of gravity that differ from Einstein's general relativity. Numerous studies have shown that different modified theories…

General Relativity and Quantum Cosmology · Physics 2015-08-05 Kostas Glampedakis , George Pappas , Hector O. Silva , Emanuele Berti

Neutron stars are compact and dense celestial objects that offer the unique opportunity to explore matter and its interactions under conditions that cannot be reproduced elsewhere in the Universe. Their extreme gravitational, rotational and…

High Energy Astrophysical Phenomena · Physics 2024-01-29 Stefano Ascenzi , Vanessa Graber , Nanda Rea

Recent observations of neutron star masses close to the maximum predicted by nucleonic equations of state begin to challenge our understanding of dense matter in neutron stars, and constrain the possible presence of quark matter in their…

Nuclear Theory · Physics 2008-11-26 Gordon Baym

The equation of state is fundamental in describing matter under the extreme conditions characteristic of neutron stars and is central to advancing our understanding of dense matter physics. A critical challenge, however, lies in accurately…

High Energy Astrophysical Phenomena · Physics 2025-01-14 Anshuman Verma , Asim Kumar Saha , Ritam Mallick