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Related papers: Newtonian and relativistic polytropes

200 papers

Based on the Rheological Paradigm, one has extended the equations of state for relativistic spherically symmetric static neutron stars, taking into consideration the derivative of the matter pressure along the so-called director…

General Relativity and Quantum Cosmology · Physics 2019-02-19 Alexander Balakin , Alexei Ilin , Anna Kotanjyan , Levon Grigoryan

The thermodynamical properties of the equation of state (EoS) of high-density matter (above nuclear saturation density) and the possible existence of exotic states such as phase transitions from nuclear/hadronic matter into quark-gluon…

High Energy Astrophysical Phenomena · Physics 2019-01-28 M. A. Aloy , J. M. Ibáñez , N. Sanchis-Gual , M. Obergaulinger , J. A. Font , S. Serna , A. Marquina

We present a class of exact solutions of Einstein's gravitational field equations describing spherically symmetric and static anisotropic stellar type configurations. The solutions are obtained by assuming a particular form of the…

General Relativity and Quantum Cosmology · Physics 2009-11-07 M. K. Mak , T. Harko

It is shown how the Equation of State (EoS) depends on nucleon properties inside Nuclear Matter (NM). We propose to benefit from the concept of enthalpy in order to include volume corrections to the nucleon rest energy, which are…

Nuclear Theory · Physics 2017-02-28 Jacek Rożynek

We utilise the phenomenologically parameterized piecewise polytropic equations of state to study various neutron star properties. We investigate the compliance of these equations of state with several astronomical observations. We also…

Nuclear Theory · Physics 2022-05-04 Jaikhomba Singha , S. Mullai Vaneshwar , Ankit Kumar

We study the dynamics of small inhomogeneities in an expanding universe collapsing to form bound structures using full solutions of the Einstein-Vlasov (N-body) equations. We compare these to standard Newtonian N-body solutions using…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-28 William E. East , Radosław Wojtak , Frans Pretorius

Precise measurements of neutron star observables (such as mass and radius) allow one to constrain the equations of state for supranuclear matter and develop a stronger understanding of nuclear physics. The Neutron star Interior Composition…

General Relativity and Quantum Cosmology · Physics 2025-01-31 Tristen Lowrey , Kent Yagi , Nicolás Yunes

We propose a new doorway to study the interplay between equations of state of dense matter and compact stars in gauge/gravity correspondence. For this we construct a bulk geometry near the boundary of five-dimensional spacetime. By solving…

High Energy Physics - Phenomenology · Physics 2015-06-05 Kyung Kiu Kim , Youngman Kim , Ik Jae Shin

As some of the most compact stellar objects in the universe, neutron stars are unique cosmic laboratories. The study of neutron stars provides an ideal theoretical testbed for investigating both physics at supra-nuclear densities as well as…

High Energy Astrophysical Phenomena · Physics 2023-05-29 Grigorios Papigkiotis , George Pappas

We derive a Tolman-Oppenheimer-Volkoff equation in neutron star systems within the modified $f(T, \mathcal{T})$-gravity class of models using a perturbative approach. In our approach $f(T, \mathcal{T})$-gravity is considered to be a static…

General Relativity and Quantum Cosmology · Physics 2017-05-08 Mark Pace , Jackson Levi Said

Spherically symmetric relativistic stars with the polytropic equation of state, which possess the local pressure anisotropy, are considered in the context of general relativity. The modified Lane-Emden equations are derived for the special…

General Relativity and Quantum Cosmology · Physics 2018-01-25 A. A. Isayev

Sound speed can be an important tool in unraveling the nature of matter that exists at the cores of neutron stars. In this study, we investigate three major classes of equations of state; monotonous, non-monotonous and discontinuous…

High Energy Astrophysical Phenomena · Physics 2025-03-24 Anshuman Verma , Asim Kumar Saha , Tuhin Malik , Ritam Mallick

Observations of neutron stars, whether in binaries or in isolation, provide information about the internal structure of the most extreme material objects in the Universe. In this work, we combine information from recent observations to…

High Energy Astrophysical Phenomena · Physics 2021-08-29 Philippe Landry , Reed Essick , Katerina Chatziioannou

We present a set of three unified equations of states (EoSs) based on the nuclear energy-density functional (EDF) theory.These EoSs are based on generalized Skyrme forces fitted to essentially all experimental atomic mass data and…

High Energy Astrophysical Phenomena · Physics 2012-07-02 A. F. Fantina , N. Chamel , J. M. Pearson , S. Goriely

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

We construct the equation of state (EOS) in a wide density range for neutron stars using the relativistic mean field theory. The properties of neutron star matter with both uniform and non-uniform distributions are studied consistently. The…

Nuclear Theory · Physics 2009-11-07 H. Shen

Multi-messenger astronomical observations of neutron stars, together with more precise calculations and constraints coming from dense matter microphysics, are generating tension with regard to equations of state models used to describe…

High Energy Astrophysical Phenomena · Physics 2026-02-09 Mauro Mariani , Ignacio F. Ranea-Sandoval

We perform a comprehensive Bayesian analysis to constrain the neutron star (NS) equation of state (EoS) using a wide range of terrestrial and astrophysical data. The terrestrial inputs include quantities related to symmetric nuclear matter…

Nuclear Theory · Physics 2026-02-19 Sk Md Adil Imam , N. K. Patra

We investigate in this paper the structures of neutron and quark stars in f(T) theory of gravity where T denotes the torsion scalar. Attention is attached to the TOV type equations of this theory and numerical integrations of these…

General Relativity and Quantum Cosmology · Physics 2016-11-29 A. V. Kpadonou , M. J. S. Houndjo , M. E. Rodrigues

The properties of matter at ultra-high densities, low temperatures, and with a significant asymmetry between protons and neutrons can be studied exclusively through astrophysical observations of neutron stars. We show that measurements of…

High Energy Astrophysical Phenomena · Physics 2010-02-16 Feryal Ozel , Dimitrios Psaltis