English
Related papers

Related papers: Dynamically stable ergostars exist: General relati…

200 papers

Rapidly rotating neutron stars can be unstable to the gravitational-wave-driven CFS mechanism if they have a neutral point in the spectrum of nonaxisymmetric f-modes. We investigate the frequencies of these modes in two sequences of…

Solar and Stellar Astrophysics · Physics 2010-11-16 Burkhard Zink , Oleg Korobkin , Erik Schnetter , Nikolaos Stergioulas

Certain relations among neutron-star observables that are insensitive to the equation of state are known to exist. Such universal relations have been shown to be valid for cold and stationary neutron stars. Here, we study these relations in…

High Energy Astrophysical Phenomena · Physics 2024-02-19 Victor Guedes , Shu Yan Lau , Cecilia Chirenti , Kent Yagi

Observed supermassive black holes in the early universe have several proposed formation channels, in part because most of these channels are difficult to probe. One of the more promising channels, the direct collapse of a supermassive star,…

Solar and Stellar Astrophysics · Physics 2022-09-14 Chris Nagele , Hideyuki Umeda , Koh Takahashi , Takashi Yoshida , Kohsuke Sumiyoshi

The Einstein static (ES) universe has played a major role in various emergent scenarios recently proposed in order to cure the problem of initial singularity of the standard model of cosmology. In the herein model, we study the existence…

General Relativity and Quantum Cosmology · Physics 2017-01-23 Hamid Shabani , Amir Hadi Ziaie

A realistic equation of state (EOS) leads to realistic strange stars (ReSS) which are compact in the mass radius plot, close to the Schwarzchild limiting line (Dey et al 1998). Many of the observed stars fit in with this kind of…

Astrophysics · Physics 2009-11-07 Monika Sinha , Jishnu Dey , Mira Dey , Subharthi Ray , Siddhartha Bhowmick , .

Quasi-equilibrium models of rapidly rotating triaxially deformed stars are computed in general relativistic gravity, assuming a conformally flat spatial geometry (Isenberg-Wilson-Mathews formulation) and a polytropic equation of state.…

Astrophysics · Physics 2009-01-08 Xing Huang , Charalampos Markakis , Noriyuki Sugiyama , Koji Uryu

We describe the results high resolution, hydrodynamic calculations of neutron star mergers. The model makes use of a new, nuclear equation of state, accounts for multi-flavour neutrino emission and solves the equations of hydrodynamics…

Astrophysics · Physics 2009-11-07 S. Rosswog

Rotations on the circle by irrational numbers give rise to uniquely ergodic Sturm dynamical systems. We show that rotations by badly approximable irrationals have the property of fast ergodicity. It was shown recently that any Sturmian…

Dynamical Systems · Mathematics 2024-01-30 Damian Głodkowski , Jacek Miȩkisz

Triaxial neutron stars may be important sources of gravitational radiation for the forthcoming generation of interferometric gravitational wave detectors such as LIGO, VIRGO, and GEO600. We investigate the viscosity triggered bar mode…

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

We perform a detailed analysis of radial oscillations to discuss dynamical stability in two-fluid neutron stars composed of ordinary nuclear matter and a gravitationally coupled dark matter component. Using a fully relativistic two-fluid…

High Energy Astrophysical Phenomena · Physics 2025-09-05 Ankit Kumar , Hajime Sotani

Exact models of uniformly rotating strange stars, built of self bound quark matter, are calculated within the framework of general relativity. This is made possible thanks to a new numerical technique capable to handle the strong density…

Astrophysics · Physics 2010-11-19 E. Gourgoulhon , P. Haensel , R. Livine , E. Paluch , S. Bonazzola , J. A. Marck

Within the context of Rastall gravity, we investigate the hydrostatic equilibrium and dynamical stability against radial pulsations of compact stars, where a free parameter $\beta$ measures the deviations from General Relativity (GR). We…

General Relativity and Quantum Cosmology · Physics 2024-07-01 Juan M. Z. Pretel , Clésio E. Mota

Gravitational radiation (GR) drives an instability in certain modes of rotating stars. This instability is strong enough in the case of the r-modes to cause their amplitudes to grow on a timescale of tens of seconds in rapidly rotating…

Astrophysics · Physics 2007-05-23 Lee Lindblom

We study secular stability against a quasi-radial oscillation for rigidly rotating stars with soft equations of state in general relativity. The polytropic equations of state with polytropic index $n$ between 3 and 3.05 are adopted for…

Astrophysics · Physics 2009-11-10 Masaru Shibata

Rapid uniform rotation of newborn neutron stars (protoneutron stars) is studied for a range of internal temperatures and entropies per baryon predicted by the existing numerical simulations. Calculations are performed using general…

Astrophysics · Physics 2008-11-26 J-O. Goussard , P. Haensel , J. L. Zdunik

We present the first numerical solutions of the coupled Einstein-Maxwell equations describing rapidly rotating neutron stars endowed with a magnetic field. These solutions are fully relativistic and self-consistent, all the effects of the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 M. Bocquet , S. Bonazzola , E. Gourgoulhon , J. Novak

Many exo-solar systems discovered in the last decade consist of planets orbiting in resonant configurations and consequently, their evolution should show long-term stability. However, due to the mutual planetary interactions a multi-planet…

Earth and Planetary Astrophysics · Physics 2013-06-12 George Voyatzis , Kyriaki I. Antoniadou , John D. Hadjidemetriou

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

The equation of state (EoS) of neutron matter plays a decisive role to understand the neutron star properties and the gravitational waves from neutron star mergers. At sufficient densities, the appearance of hyperons generally softens the…

Nuclear Theory · Physics 2025-02-21 Hui Tong , Serdar Elhatisari , Ulf-G. Meißner

It has been recently argued through numerical work that rotating stars with a high degree of differential rotation are dynamically unstable against bar-mode deformation, even for values of the ratio of rotational kinetic energy to…

Astrophysics · Physics 2009-06-23 Pablo Cerdá-Durán , Vicent Quilis , José A. Font
‹ Prev 1 8 9 10 Next ›