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Related papers: Stability of Force-Free Magnetospheres

200 papers

We investigate regular rotating black holes predicted by asymptotically safe gravity, where the Newton constant varies with energy scale and modifies the near horizon geometry. These solutions remain asymptotically flat and avoid central…

General Relativity and Quantum Cosmology · Physics 2025-10-01 Chirantana Bhattacharjee , Subhadip Sau , Avijit Mukherjee

We introduce an ansatz for force-free electrodynamics in Minkowski spacetime under which the nonlinear system reduces to a semilinear scalar wave equation depending on two spacetime variables. This reduction yields explicit time-dependent…

General Relativity and Quantum Cosmology · Physics 2026-04-20 Yafet E. Sanchez Sanchez

The study of charged particle dynamics in the combined gravitational and magnetic field can provide important theoretical insight into astrophysical processes around black holes. In this paper, we explore the charged particle dynamics in…

General Relativity and Quantum Cosmology · Physics 2024-03-19 Martin Kološ , Misbah Shahzadi , Arman Tursunov

In low-luminosity active galactic nuclei like M87* and Sgr A*, the accretion disk around the central supermassive black hole is tenuous and collisionless. As a result, the usual ideal magnetohydrodynamics (MHD) approximation may not be…

High Energy Astrophysical Phenomena · Physics 2026-02-26 John M. Mehlhaff , Alexander Y. Chen , Martin Luepker , Yajie Yuan

We investigate in details properties of stationary force-free magnetosphere of aligned rotator assuming the last closed field line lying in equatorial plane at large distances from pulsar. The pulsar equations is solved numerically using…

Astrophysics · Physics 2009-11-11 A. N. Timokhin

Magnetically arrested accretion discs (MADs), where the magnetic pressure in the inner disc is dynamically important, provide an alternative mechanism for regulating accretion to what is commonly assumed in black hole systems. We show that…

High Energy Astrophysical Phenomena · Physics 2015-06-18 Jason Dexter , Jonathan C. McKinney , Sera Markoff , Alexander Tchekhovskoy

We study the long-term quasi-steady evolution of the force-free magnetosphere of a magnetar coupled to its internal magnetic field. We find that magnetospheric currents can be maintained on long timescales of the order of thousands of…

High Energy Astrophysical Phenomena · Physics 2018-10-11 Taner Akgün , Pablo Cerdá-Durán , Juan Antonio Miralles , José A. Pons

A resistive magnetohydrodynamics simulation with a dynamo term is performed for modeling the collapsar in full general relativity. As an initial condition, a spinning black hole and infalling stellar matter are modeled based on a stellar…

High Energy Astrophysical Phenomena · Physics 2025-02-05 Masaru Shibata , Sho Fujibayashi , Shinya Wanajo , Kunihito Ioka , Alan Tsz-Lok Lam , Yuichiro Sekiguchi

Abridged. Fast rotating and self-gravitating astrophysical objects suffer strong deformations from centrifugal forces. If moreover they are magnetized, they generate an electromagnetic wave that is perturbed accordingly. When stellar…

High Energy Astrophysical Phenomena · Physics 2022-03-23 Jérôme Pétri

Collapse of massive stars may result in formation of accreting black holes in their interior. The accreting stellar matter may advect substantial magnetic flux onto the black hole and promote release of its rotational energy via magnetic…

High Energy Astrophysical Phenomena · Physics 2015-05-13 S. S. Komissarov , M. V. Barkov

In the present work, we study the classical behavior of an electric dipole in presence of an external uniform magnetic field. We derive equations and constants of motion from the Lagrangian formulation. We obtain an infinitely periodic…

Classical Physics · Physics 2009-11-11 Paulina I. Troncoso , Sergio Curilef

Under conditions prevailing in certain classes of compact astrophysical systems, the active magnetosphere of a rotating black hole becomes charge-starved, giving rise to formation of a spark gap in which plasma is continuously produced. The…

High Energy Astrophysical Phenomena · Physics 2017-12-20 Amir Levinson , Noam Segev

Charged particles interacting with electromagnetic waves have a portion of their energy tied up in wave-driven oscillations. When these waves are localized to the exhaust of linear magnetic confinement systems this ponderomotive effect can…

Plasma Physics · Physics 2024-08-19 T. Rubin , I. E. Ochs , N. J. Fisch

We study the gravitational perturbations of black holes in quadratic gravity, in which the Einstein-Hilbert term is supplemented by quadratic terms in the curvature tensor. In this class of theories, the Schwarzschild solution can coexist…

General Relativity and Quantum Cosmology · Physics 2025-05-05 Georgios Antoniou , Leonardo Gualtieri , Paolo Pani

A phase space is built that allows to study, classify and compare easily large classes of static spherically symmetric wormholes solutions, sustained by an isotropic perfect fluid in General Relativity. We determine the possible locations…

General Relativity and Quantum Cosmology · Physics 2020-01-01 Stephane Fay

We consider the Maxwell's equations with perfect electric conductor boundary conditions in three-dimensional unbounded domains which are the union of a bounded resonator and one or several semi-infinite waveguides. We are interested in the…

Analysis of PDEs · Mathematics 2025-12-22 Anne-Sophie Bonnet-Ben Dhia , Lucas Chesnel , Sonia Fliss

We study static, spherically symmetric black hole solutions of the Einstein equations with a positive cosmological constant and a conformally coupled self interacting scalar field. Exact solutions for this model found by Mart{\'\i}nez,…

High Energy Physics - Theory · Physics 2008-11-26 Gustavo Dotti , Reinaldo J. Gleiser , Cristian Martinez

The standing MHD modes in a zero-$\beta$ cylindrical magnetic flux tube modelled as a straight core surrounded by a magnetically twisted annulus, both embedded in a straight ambient external field is considered. The dispersion relation for…

Astrophysics · Physics 2009-11-13 K. Karami , M. Barin

Rotating charged black strings are solutions of four-dimensional Einstein-Maxwell equations with a negative cosmological constant and a non-trivial topology. According to the AdS/CFT correspondence, these black strings are dual to rotating…

General Relativity and Quantum Cosmology · Physics 2015-11-18 Alex S. Miranda , Jaqueline Morgan , Vilson T. Zanchin , Alejandra Kandus

We study the dynamics of odd-parity perturbations on a static and spherically symmetric black hole background with a timelike vector field based on the effective field theory (EFT) approach. We derive the quadratic Lagrangian written in…

General Relativity and Quantum Cosmology · Physics 2025-11-11 Shogo Tomizuka , Hajime Kobayashi , Naritaka Oshita , Kazufumi Takahashi , Shinji Mukohyama