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Related papers: Compact stars in Rastall gravity: hydrostatic equi…

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We present new results on instabilities in rapidly and differentially rotating neutron stars. We model the stars in full general relativity and describe the stellar matter adopting a cold realistic equation of state based on the unified SLy…

General Relativity and Quantum Cosmology · Physics 2010-06-01 Giovanni Corvino , Luciano Rezzolla , Sebastiano Bernuzzi , Roberto De Pietri , Bruno Giacomazzo

We investigate the nature of low T/W dynamical instabilities in differentially rotating stars by means of linear perturbation. Here, T and W represent rotational kinetic energy and the gravitational binding energy of the star. This is the…

Solar and Stellar Astrophysics · Physics 2016-10-25 Motoyuki Saijo , Shin'ichirou Yoshida

Equilibrium states in galactic dynamics can be described as stationary solutions of the Vlasov-Poisson system, which is the non-relativistic case, or of the Vlasov-Einstein system, which is the relativistic case. To obtain spherically…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Gerhard Rein , Alan D. Rendall

Taking a novel approach, this paper discuss the structure of compact stars, an important topic in theoretical astrophysics. Adopting the Newtonian gravitation, we solve the hydrostatic equilibrium equation by imposing a simple…

Solar and Stellar Astrophysics · Physics 2014-07-22 Hilario Rodrigues

We investigate the hydrostatic equilibrium of stellar structure by taking into account the modi- fied La\'e-Emden equation coming out from f(R)-gravity. Such an equation is obtained in metric approach by considering the Newtonian limit of…

General Relativity and Quantum Cosmology · Physics 2011-03-21 S. Capozziello , M. De Laurentis , S. D. Odintsov , A. Stabile

We investigate the nature of low T/W dynamical instabilities in various ranges of the stiffness of the equation of state in differentially rotating stars. Here T is the rotational kinetic energy, while W the gravitational binding energy. We…

High Energy Astrophysical Phenomena · Physics 2018-07-05 Motoyuki Saijo

In this work we analyze hydrostatic equilibrium configurations of neutron stars in a non-minimal geometry-matter coupling (GMC) theory of gravity. We begin with the derivation of the hydrostatic equilibrium equations for the $f(R,L) $…

General Relativity and Quantum Cosmology · Physics 2020-05-14 G. A. Carvalho , P. H. R. S. Moraes , S. I. dos Santos , B. S. Gonçalves , M. Malheiro

In this paper, we consider a spherical symmetric metric to extract the hydrostatic equilibrium equation of stars in $(3+1)-$dimensional gravity's rainbow in the presence of cosmological constant. Then, we generalize the hydrostatic…

High Energy Physics - Theory · Physics 2016-09-19 S. H. Hendi , G. H. Bordbar , B. Eslam Panah , S. Panahiyan

This paper studies the structural formation of various spherically symmetric anisotropic configured stars in $f(\mathcal{R},\mathcal{T},\mathcal{Q})$ gravity under the influence of electromagnetic field, where…

General Relativity and Quantum Cosmology · Physics 2023-07-24 M. Sharif , Tayyab Naseer

The main objective of this article is to study the viable compact stellar structures in non-Riemannian geometry, i.e., $f(\mathbb{Q},T)$ theory, where $\mathbb{Q}$ defines the non-metricity and $T$ represents trace of the stress-energy…

General Relativity and Quantum Cosmology · Physics 2024-04-02 M. Zeeshan Gul , M. Sharif , Adeeba Arooj

Gravastars are considered as one of the prime exotic type compact objects which may be found at the end state of gravitational collapse of massive stars with a view to resolve the complexities that are pertinent in case of a black hole…

General Relativity and Quantum Cosmology · Physics 2024-08-22 Debadri Bhattacharjee , Pradip Kumar Chattopadhyay

Starting from hydrodynamic equations, we have established a set of hydrodynamic equations for average flow and a set of dynamic equations of auto- and cross-correlations of turbulent velocity and temperature fluctuations, following the…

Solar and Stellar Astrophysics · Physics 2018-08-30 D. R. Xiong , L. Deng , C. Zhang

In Horava-Lifshitz gravity, regularity of a solution requires smoothness of not only the spacetime geometry but also the foliation. As a result, the regularity condition at the center of a star is more restrictive than in general…

High Energy Physics - Theory · Physics 2010-04-06 Keisuke Izumi , Shinji Mukohyama

In [Leung et al., Phys. Rev. D 84, 107301 (2011)], we presented our results on using a general relativistic two-fluid formalism to study the hydrostatic equilibrium configuration of an admixture of degenerate dark matter and normal nuclear…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-04 S. -C. Leung , M. -C. Chu , L. -M. Lin

We develop a fully relativistic approach for determining the response of a compact star to a time/frequency dependent (tidal) environment. The strategy involves matching the solution for the linearised fluid dynamics in the star's interior…

General Relativity and Quantum Cosmology · Physics 2026-03-25 Nils Andersson , Rhys Counsell , Fabian Gittins , Suprovo Ghosh

The relativistic equations of hydrostatic equilibrium for a spherically symmetric star, or the Tolman-Oppenheimer-Volkoff equations are known in higher dimensions. In this paper, these equations have been expressed in terms of parameters of…

General Relativity and Quantum Cosmology · Physics 2020-10-21 Manjari Bagchi

In this study, we present a generalized spherically symmetric, anisotropic and static compact stellar model in $f(T)$ gravity, where $T$ represents the torsion scalar. By employing the Karmarkar condition we have obtained embedding class 1…

General Relativity and Quantum Cosmology · Physics 2018-11-30 Debabrata Deb , Shounak Ghosh , S. K. Maurya , Maxim Khlopov , Saibal Ray

We investigate the geodesic structure of realistic static and spherically symmetric spacetimes embedding neutron stars in metric $f(R)$ gravity, focusing on the quadratic Starobinsky model $f(R)=aR^2$ with $a<0$. Neutron-star solutions are…

General Relativity and Quantum Cosmology · Physics 2026-03-10 Néstor Rivero González , Álvaro de la Cruz Dombriz , Gonzalo J. Olmo

We investigate the fundamental mode of non-radial oscillations of non-rotating compact stars in general relativity using a set of equations of state (EOS) connecting state-of-the-art calculations at low and high densities. Specifically, a…

High Energy Astrophysical Phenomena · Physics 2018-09-05 C. Vásquez Flores , G. Lugones

Hydrodynamic instabilities and turbulence in neutron stars have been suggested to be related to observable spin variations in pulsars, such as spin glitches, timing noise, and precession (nutation). Accounting for the stabilizing effects of…

High Energy Astrophysical Phenomena · Physics 2018-10-10 C. A. van Eysden , Bennett Link