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Related papers: Slowly rotating dark energy stars

200 papers

We present an equation of state for elastic matter which allows for purely longitudinal elastic waves in all propagation directions, not just principal directions. The speed of these waves is equal to the speed of light whereas the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Max Karlovini , Lars Samuelsson

We numerically calculate equilibrium configurations of uniformly rotating and charged neutron stars, in the case of insulating material and neglecting the electromagnetic forces acting on the equilibrium of the fluid. This allows us to…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Jerome Novak , Emmanuel Marcq

Simulations in general relativity show that the outcome of collapse of a marginally unstable, uniformly rotating star spinning at the mass-shedding limit depends critically on the equation of state. For a very stiff equation of state, which…

Astrophysics · Physics 2009-11-10 Stuart L. Shapiro

We study rotating compact stars that are mixtures of the ordinary nuclear matter in a neutron star and fermionic dark matter. After deriving equations describing a slowly rotating system made up of an arbitrary number of perfect fluids, we…

General Relativity and Quantum Cosmology · Physics 2023-11-15 John Cronin , Xinyang Zhang , Ben Kain

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

Neutron stars are the densest, directly observable stellar objects in the universe and serve as unique astrophysical laboratories to study the behavior of matter under extreme physical conditions. This book chapter is devoted to describing…

High Energy Astrophysical Phenomena · Physics 2018-06-11 N. Degenaar , V. F. Suleimanov

A full-relativistic approach is used to compute the radius of the innermost stable circular orbit (ISCO), the Keplerian, frame-dragging, precession and oscillation frequencies of the radial and vertical motions of neutral test particles…

Solar and Stellar Astrophysics · Physics 2014-01-14 Andres F. Gutierrez-Ruiz , Cesar A. Valenzuela-Toledo , Leonardo A. Pachon

We assume the cosmological dark sector to consist of pressureless matter and holographic dark energy with a cutoff length proportional to the Ricci scale. The requirement of separate energy-momentum conservation of the components is shown…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Sergio del Campo , Júlio. C. Fabris , Ramón Herrera , Winfried Zimdahl

We present the first systematic study of rigidly rotating protoquark stars based on isentropic equations of state (EOS) within the density-dependent quark mass (DDQM) framework. Using a quasi-static equilibrium approach, we follow the…

High Energy Astrophysical Phenomena · Physics 2026-01-21 Adamu Issifu , Andreas Konstantinou , Prashant Thakur , Tobias Frederico

In general relativity, the tangential speed of objects in stable circular orbits is not uniquely described by the orbital radius and the mass present inside the orbital radius. This work presents a static, spherically symmetric spacetime…

General Relativity and Quantum Cosmology · Physics 2025-04-24 C. Mallary

In present paper a spherically symmetric stellar configuration has been analyzed by assuming the matter distribution of the stellar configuration is anisotropic in nature and compared with the realistic objects, namely, the low mass X-ray…

General Relativity and Quantum Cosmology · Physics 2021-08-26 Piyali Bhar , Tuhina Manna , Farook Rahaman , Ayan Banerjee

We propose a new method to study the quasi-normal modes of rotating relativistic stars. Oscillations are treated as perturbations in the frequency domain of the stationary, axisymmetric background describing a rotating star. The perturbed…

General Relativity and Quantum Cosmology · Physics 2008-11-26 V. Ferrari , L. Gualtieri , S. Marassi

We investigate the structure and stability properties of compact astrophysical objects that may be formed from the Bose-Einstein condensation of dark matter. Once the critical temperature of a boson gas is less than the critical…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-25 X. Y. Li , T. Harko , K. S. Cheng

One of the most common assumptions in the study of neutron star models and their oscillations is that the pressure is isotopic, however there are arguments that this may not be correct. Thus in the present paper we make a first step towards…

General Relativity and Quantum Cosmology · Physics 2012-06-25 Daniela D. Doneva , Stoytcho S. Yazadjiev

We consider rotating boson star solutions in a three-dimensional anti-de Sitter spacetime and investigate the influence of the rotation on their properties. The mass and angular momentum of these configurations are computed by using the…

General Relativity and Quantum Cosmology · Physics 2010-04-05 Dumitru Astefanesei , Eugen Radu

We consider the slowly rotating relativistic stars with a uniform angular velocity in the scalar-tensor gravity, and examine the rotational effect around such compact objects. For this purpose, we derive a 2nd order differential equation…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Hajime Sotani

The properties of exotic stars are investigated. In particular, we study objects made entirely of dark matter and we take into account intrinsic anisotropies which have been ignored so far. We obtain exact analytical solutions to the…

General Relativity and Quantum Cosmology · Physics 2021-04-21 Pedro H. R. S. Moraes , Grigoris Panotopoulos , Ilidio Lopes

On the base of an exact solution for the static spherically symmetric Einstein equations with the quintessential dark matter, we explain the asymptotic behavior of rotation curves in spiral galaxies. The parameter of the quintessence state,…

General Relativity and Quantum Cosmology · Physics 2007-05-23 V. V. Kiselev

The evolution of a nonaxisymmetric bar-mode perturbation of rapidly rotating stars due to a secular instability induced by gravitational wave emission is studied in post-Newtonian simulations taking into account gravitational radiation…

Astrophysics · Physics 2010-11-19 Masaru Shibata , Sigeyuki Karino

In this paper, we study the existence of strange star in the background of f (T) modified gravity where T is a scalar torsion. In KB metric space, we derive the equations of motion using anisotropic property within the spherically strange…

General Relativity and Quantum Cosmology · Physics 2018-10-25 Pameli Saha , Ujjal Debnath