English
Related papers

Related papers: A novel formulation for the evolution of relativis…

200 papers

We report on general relativistic calculations of quasiequilibrium configurations of binary neutron stars in circular orbits with zero vorticity. These configurations are expected to represent realistic situations as opposed to corotating…

General Relativity and Quantum Cosmology · Physics 2009-10-31 S. Bonazzola , E. Gourgoulhon , J. -A. Marck

A key obstacle to developing a satisfying theory of galaxy evolution is the difficulty in extending analytic descriptions of early structure formation into full nonlinearity, the regime in which galaxy growth occurs. Extant techniques,…

We study spherically symmetric solutions to the Einstein-Euler equations which model an idealized relativistic neutron star surrounded by vacuum. These are barotropic fluids with a free boundary, governed by an equation of state which sets…

Analysis of PDEs · Mathematics 2021-08-16 Grigorios Fournodavlos , Volker Schlue

The problem of solving perturbatively the equations describing the evolution of self-gravitating collisionless matter in an expanding universe considerably simplifies when directly formulated in terms of the gravitational and velocity…

Astrophysics · Physics 2015-06-24 Paolo Catelan , Francesco Lucchin , Sabino Matarrese , Lauro Moscardini

We develop a covariant variational framework for relativistic electromagnetic continua (fluids and solid) based on Hamilton's principle formulated directly in the material description. The approach extends the geometric theory of…

Mathematical Physics · Physics 2025-11-25 Francçois Gay-Balmaz

We present a semi-Lagrangian characteristic mapping method for the incompressible Euler equations on a rotating sphere. The numerical method uses a spatio-temporal discretization of the inverse flow map generated by the Eulerian velocity as…

Numerical Analysis · Mathematics 2023-10-20 Seth Taylor , Jean-Christophe Nave

We apply the Hartle formalism to study equilibrium configurations in the framework of Newtonian gravity. This approach allows one to study in a simple manner the properties of the interior gravitational field in the case of static as well…

Solar and Stellar Astrophysics · Physics 2016-05-04 Kuantay Boshkayev , Hernando Quevedo , Zhanerke Kalymova , Bakytzhan Zhami

Planetary, stellar and galactic physics often rely on the general restricted gravitational N-body problem to model the motion of a small-mass object under the influence of much more massive objects. Here, I formulate the general restricted…

Earth and Planetary Astrophysics · Physics 2015-06-18 Dimitri Veras

We study the nonlinear gravitational dynamics of a universe filled with a pressureless fluid and a cosmological constant $\Lambda$ in the context of Newtonian gravity, and in the relativistic post-Friedmann approach proposed in paper I [I.…

General Relativity and Quantum Cosmology · Physics 2016-10-26 Cornelius Rampf , Eleonora Villa , Daniele Bertacca , Marco Bruni

We present a numerical model for uniformly rotating superfluid neutron stars, for the first time with realistic microphysics including entrainment, in a fully general relativistic framework. We compute stationary and axisymmetric…

High Energy Astrophysical Phenomena · Physics 2016-11-04 Aurélien Sourie , Micaela Oertel , Jérôme Novak

We analyze numerical approximations for axisymmetric two-phase flow in the arbitrary Lagrangian-Eulerian (ALE) framework. We consider a parametric formulation for the evolving fluid interface in terms of a one-dimensional generating curve.…

Numerical Analysis · Mathematics 2023-12-25 Harald Garcke , Robert Nürnberg , Quan Zhao

Solving dynamical problems in general relativity requires the full machinery of numerical relativity. Wilson has proposed a simpler but approximate scheme for systems near equilibrium, like binary neutron stars. We test the scheme on…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Gregory B. Cook , Stuart L. Shapiro , Saul A. Teukolsky

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

We discuss the equilibrium conditions for a body made of two homogeneous components separated by oblate spheroidal surfaces and in relative motion. While exact solutions are not permitted for rigid rotation (unless a specific ambient…

Solar and Stellar Astrophysics · Physics 2022-04-13 Jean-Marc Huré

The Lagrangian dynamics of a single fluid element within a self-gravitational matter field is intrinsically non-local due to the presence of the tidal force. This complicates the theoretical investigation of the non-linear evolution of…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-23 Xin Wang , Alex Szalay

We solve the nonlinear evolution of pressureless, irrotational density fluctuations in a perturbed Robertson-Walker spacetime using a new Lagrangian method based on the velocity gradient and gravity gradient tensors. Borrowing results from…

Astrophysics · Physics 2009-10-22 Edmund Bertschinger , Bhuvnesh Jain

We study static, spherically symmetric equilibrium configurations in extended theories of gravity (ETG) following the notation introduced by Capozziello et {\it al}. We calculate the differential equations for the stellar structure in such…

General Relativity and Quantum Cosmology · Physics 2016-12-22 Aneta Wojnar , Hermano Velten

The general solution of hydrostatic equilibrium equations for a two-component fluid of ions and electrons without a local electroneutrality constraint is found in the framework of Newtonian gravity theory. In agreement with the Poincar\'e…

Solar and Stellar Astrophysics · Physics 2018-09-18 M. I. Krivoruchenko , D. K. Nadyozhin , A. V. Yudin

We present relativistic hydrostatic equations for obtaining irrotational binary neutron stars in quasi equilibrium states in 3+1 formalism. Equations derived here are different from those previously given by Bonazzola, Gourgoulhon, and…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Masaru Shibata

The present article investigates the possibility of reconstruction of the generic function in $F(\mathcal{R},T)$ gravitational theory by considering some well-known cosmological bouncing models namely exponential evaluation, oscillatory,…

General Relativity and Quantum Cosmology · Physics 2022-10-26 M. Zubair , Quratulien Muneer , Saira Waheed