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Related papers: Stability Analysis of Stellar Radiating Filaments

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We investigated the stability condition in $f(T,\phi)$ gravity theory for considering two models by using dynamical system. We assume the forms of $G(T)$ are $(i)$ $G(T)$ = $\alpha T+\frac{\beta}{T}$, $(ii)$ $G(T)$ = $\zeta T$ ln$(\psi T)$,…

General Relativity and Quantum Cosmology · Physics 2023-06-14 Amit Samaddar , S. Surendra Singh

In the metric approach of $f(R)$ theories of gravity, the fourth-order field equations are often recast as effective Einstein equations in the presence of standard matter and a curvature fluid (which gathers all the extra terms), always in…

General Relativity and Quantum Cosmology · Physics 2020-12-01 Juan M. Z. Pretel , Sergio E. Jorás , Ribamar R. R. Reis

We investigate the dynamical stability of bootstrapped Newtonian stars following homologous adiabatic perturbations, focusing on objects of low or intermediate compactness. The results show that for stars with homogeneous densities these…

General Relativity and Quantum Cosmology · Physics 2024-08-08 Octavian Micu

The aim of this paper is to reconstruct and analyze the stability of some cosmological models against linear perturbations in $f(\mathcal{G},T)$ gravity ($\mathcal{G}$ and $T$ represent the Gauss-Bonnet invariant and trace of the…

General Relativity and Quantum Cosmology · Physics 2017-06-22 M. Sharif , Ayesha Ikram

In this paper, we evaluate the complexity of the non-static cylindrical geometry with anisotropic matter configuration in the framework of modified Gauss-Bonnet theory. In this perspective, we calculate modified field equations, the C…

General Relativity and Quantum Cosmology · Physics 2025-06-05 M. Zeeshan Gul , W. Ahmad , M. M. M. Nasir , Faisal Javed , Orhan Donmez , Bander Almutairi

We examine the static structure configurations and radial stability of compact stars within the context of $f(R, T)$ gravity, with $R$ and $T$ standing for the Ricci scalar and trace of the energy-momentum tensor, respectively. Considering…

General Relativity and Quantum Cosmology · Physics 2021-04-26 Juan M. Z. Pretel , Sergio E. Jorás , Ribamar R. R. Reis , José D. V. Arbañil

This paper explores the viability and stability of compact stellar objects characterized by anisotropic matter in the framework of $f(\mathrm{Q},\mathrm{T})$ theory, where $\mathrm{Q}$ denotes non-metricity and $\mathrm{T}$ represents the…

General Relativity and Quantum Cosmology · Physics 2024-07-08 M. Zeeshan Gul , M. Sharif , Adeeba Arooj

In this work, we explore the cosmological stability of $f(Q, B)$ gravity using a dynamical system approach, where $Q$ denotes the nonmetricity scalar and $B$ represents the boundary term. We determine the model parameters of $f(Q, B)$…

General Relativity and Quantum Cosmology · Physics 2024-12-25 Santosh V. Lohakare , B. Mishra

The dynamical instability of relativistic polytropic spheres, embedded in a spacetime with a repulsive cosmological constant, is studied in the framework of general relativity. We apply the methods used in our preceding paper to study the…

General Relativity and Quantum Cosmology · Physics 2020-07-22 Camilo Posada , Jan Hladík , Zdenek Stuchlík

A re-investigation of the gravothermal catastrophe is presented. By means of a linear perturbation analysis, we study the dynamical stability of a spherical self-gravitating isothermal fluid of finite volume and find that the conditions for…

Astrophysics of Galaxies · Physics 2015-06-12 M. C. Sormani , G. Bertin

We study the stability of neutron stars with toroidal magnetic fields by magnetohydrodynamic simulation in full general relativity under assumption of axial symmetry. Nonrotating and rigidly rotating neutron stars are prepared for a variety…

Astrophysics · Physics 2008-12-18 Kenta Kiuchi , Masaru Shibata , Shijun Yoshida

Understanding the role of pressure anisotropy and dissipation is crucial for modelling compact objects' internal structure and observable properties. In this work, we reinterpret local pressure anisotropy in relativistic stellar structures…

General Relativity and Quantum Cosmology · Physics 2025-03-19 Justo Ospino , Daniel Suárez-Urango , Laura M. Becerra , Héctor Hernández , Luis A. Núñez

The question is addressed whether stellar differentially rotating radiative zones (like the solar tachocline) excite nonaxisymmetric r-modes which can be observed. To this end the hydrodynamical stability of latitudinal differential…

Solar and Stellar Astrophysics · Physics 2015-05-13 L. L. Kitchatinov , G. Rüdiger

We introduce a Newtonian model for the deformations of a compressible, autogravitating, and continuously stratified neutron star. The present framework can be applied to a number of astrophysical scenarios as it allows us to account for a…

High Energy Astrophysical Phenomena · Physics 2020-01-15 Elia Giliberti , Gabriele Cambiotti , Marco Antonelli , Pierre Pizzochero

It is known that a finite-size homogeneous granular fluid develops an hydrodynamic-like instability when dissipation crosses a threshold value. This instability is analyzed in terms of modified hydrodynamic equations: first, a source term…

Statistical Mechanics · Physics 2009-10-31 R. Soto , M. Mareschal , M. Malek Mansour

We study linear time-invariant dissipative Hamiltonian differential-algebraic systems. We characterize when the systems are robustly asymptotically stable and derive exact conditions and bounds when this property is lost under…

Dynamical Systems · Mathematics 2026-05-15 Peter Benner , Volker Mehrmann , Anshul Prajapati , Punit Sharma

Gravitational stability of a disc consisting of the gaseous and the stellar components are studied in the linear regime when the gaseous component is turbulent. A phenomenological approach is adopted to describe the turbulence, in which not…

Astrophysics of Galaxies · Physics 2015-06-03 Mohsen Shadmehri , Fazeleh Khajenabi

We have developed a formalism to study non-adiabatic, non-radial oscillations of non-rotating compact stars in the frequency domain, including the effects of thermal diffusion in the framework of general relativistic perturbation theory.…

General Relativity and Quantum Cosmology · Physics 2009-11-10 L. Gualtieri , J. A. Pons , G. Miniutti

We investigate the cosmic dynamics of Rastall gravity in non-flat Friedmann-Robertson-Walker (FRW) space-time with barotropic fluid. In this context, we are concerned about the class of model satisfying the affine equation of state. We…

General Relativity and Quantum Cosmology · Physics 2022-07-27 Ashutosh Singh , Gyan Prakash Singh , Anirudh Pradhan

In this paper, stellar hydrostatic equilibrium configuration of the compact stars (neutron stars and strange stars) has been studied for $f(\mathcal{G},T)$ gravity model, with $\mathcal{G}$ and $T$ being the Gauss-Bonnet invariant and the…

General Physics · Physics 2019-11-05 M. Farasat Shamir , Mushtaq Ahmad