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Related papers: Neutron Stars as Perfect Fluids: Extracting the Li…

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We develop a description of tidal effects in astrophysical systems using effective field theory techniques. While our approach is equally capable of describing objects in the Newtonian regime (e.g. moons, rocky planets, main sequence stars,…

General Relativity and Quantum Cosmology · Physics 2016-03-29 Solomon Endlich , Riccardo Penco

In the present paper we have developed a Non-Commutative (NC) generalization of perfect fluid model from first principles, in a Hamiltonian framework. The noncommutativity is introduced at the Lagrangian (particle) coordinate space brackets…

High Energy Physics - Theory · Physics 2017-01-20 Praloy Das , Subir Ghosh

The suppression of the neutron superfluid fraction in the inner crust of a cold neutron star is mitigated by the quantum zero-point motion of ions about their equilibrium position. In turn, the crustal dynamics is altered by the presence of…

High Energy Astrophysical Phenomena · Physics 2026-05-21 Nicolas Chamel

Neutron star tidal deformability extracted from gravitational wave data provides a novel probe to the interior neutron star structures and the associated nuclear equation of state (EOS). Instead of the popular composition of nucleons and…

Nuclear Theory · Physics 2021-09-27 W. Z. Shangguan , Z. Q. Huang , S. N. Wei , W. Z. Jiang

In metric-affine gravity, both the gravitational and matter actions depend not just on the metric, but also on the independent affine connection. Thus matter can be modeled as a hyperfluid, characterized by both the energy-momentum and…

General Relativity and Quantum Cosmology · Physics 2025-03-25 Ilaria Andrei , Damianos Iosifidis , Laur Järv , Margus Saal

We study the superfluid dynamics of the outer core of neutron stars by means of a hydrodynamic model made of a neutronic superfluid and a protonic superconductor, coupled by both the dynamic entrainment and the Skyrme SLy4 nucleon-nucleon…

Nuclear Theory · Physics 2021-06-23 J. A. Gil Granados , A. Muñoz Mateo , X. Viñas

Magnetic field evolution in neutron star cores is not fully understood. We describe the field evolution both for one barotropic fluid as well as two collisionally coupled barotropic fluids with different density profiles using the anelastic…

High Energy Astrophysical Phenomena · Physics 2025-12-16 Andrei Igoshev , Nicolás A. Moraga , Andreas Reisenegger , Calum S. Skene , Rainer Hollerbach

Gravitational waves from neutron-star and black-hole binaries carry valuable information on their physical properties and probe physics inaccessible to the laboratory. Although development of black-hole gravitational-wave templates in the…

General Relativity and Quantum Cosmology · Physics 2014-10-30 Charalampos M. Markakis

Eccentric compact binaries pose not only a challenge for gravitational wave detectors, but also provide a probe into the nuclear equation of state if one of the objects is a neutron star. At the short pericenter passage, tidal interactions…

General Relativity and Quantum Cosmology · Physics 2022-02-10 Jose Nijaid Arredondo , Nicholas Loutrel

Contents: 1. Introduction 2. Spontaneous symmetry breaking 2.1 Review of classical results about Maclaurin/Jacobi ellipsoids 2.2 Spontaneous breaking of symmetry: a general phenomenom 2.3 Previous results for compressible Newtonian stars…

Astrophysics · Physics 2007-05-23 S. Bonazzola , E. Gourgoulhon

A family of exact relativistic stellar models is described. The family generalizes Buchdahl's n=1 polytropic solution. The matter content is a perfect fluid and, excluding Buchdahl's original model, it behaves as a liquid at low pressures…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Kjell Rosquist

Fermion soliton stars are a consistent model of exotic compact objects which involve a nonlinear interaction between a real scalar field and fermions through a Yukawa term. This interaction results in an effective fermion mass that depends…

General Relativity and Quantum Cosmology · Physics 2024-06-07 Emanuele Berti , Valerio De Luca , Loris Del Grosso , Paolo Pani

We present a geometrical derivation of the relativistic dynamics of the superfluid inner crust of a neutron star. The resulting model is analogous to the Hall-Vinen-Bekarevich-Khalatnikov hydrodynamics for a single-component superfluid at…

High Energy Astrophysical Phenomena · Physics 2021-02-23 Lorenzo Gavassino , Marco Antonelli , Brynmor Haskell

Motivated by the historical detection of gravitational waves from GW170817, the neutron star and the neutron drop, i.e., a certain number of neutrons confined in an external field, are systematically investigated by ab initio calculations…

Nuclear Theory · Physics 2020-03-18 Hui Tong , Peng-Wei Zhao , Jie Meng

In this paper, we present a new hydrostatic equilibrium equation related to dilaton gravity. We consider a spherical symmetric metric to obtain the hydrostatic equilibrium equation of stars in $4$-dimensions, and generalize TOV equation to…

General Relativity and Quantum Cosmology · Physics 2015-07-27 S. H. Hendi , G. H. Bordbar , B. Eslam Panah , M. Najafi

R-modes of a rotating neutron star are unstable because of the emission of gravitational radiation. We explore the saturation amplitudes of these modes determined by nonlinear mode-mode coupling. Modelling the star as incompressible allows…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Jeandrew Brink , Saul A. Teukolsky , Ira Wasserman

We derive from first principles equations governing (a) the quadrupole tensor of a star distorted by both rotation and the presence of a companion in a possibly eccentric orbit, (b) a functional form for the dissipative force of tidal…

Astrophysics · Physics 2009-10-30 Peter P. Eggleton , Ludmila G. Kiseleva , Piet Hut

We apply the 1+1+2 covariant semi-tetrad approach to describe a general static and spherically symmetric relativistic stellar object which contains two fluids with anisotropic pressure. The corresponding Tolman-Oppenheimer-Volkoff equations…

General Relativity and Quantum Cosmology · Physics 2023-01-04 Nolene F. Naidu , Sante Carloni , Peter Dunsby

We have designed and tested a new relativistic Lagrangian hydrodynamics code, which treats gravity in the conformally flat approximation to general relativity. We have tested the resulting code extensively, finding that it performs well for…

Astrophysics · Physics 2008-11-26 Joshua Faber , Philippe Grandclément , Frederic Rasio

The linear response of a nonrelativistic superfluid baryon system on an external weak field is investigated while taking into account of the Fermi-liquid interactions. We generalize the theory developed by Leggett for a superfluid…

High Energy Astrophysical Phenomena · Physics 2009-08-07 L. B. Leinson