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Related papers: Blandford-Znajek jets in MOdified Gravity

200 papers

In order to investigate formation of relativistic jets at the center of a progenitor of a long gamma-ray burst (GRB), we develop a two-dimensional general relativistic magnetohydrodynamic (GRMHD) code. We show the code passes many,…

High Energy Astrophysical Phenomena · Physics 2009-10-02 S. Nagataki

We have performed a series of numerical experiments aimed at studying the activation of Kerr black holes (BHs) by advection of small scale magnetic fields. Such configurations may potentially give rise to the formation of quasi-striped…

High Energy Astrophysical Phenomena · Physics 2021-09-15 Anna Chashkina , Omer Bromberg , Amir Levinson

The general-relativistic magnetohydrodynamical (GRMHD) formulation for black hole-powered jets naturally gives rise to a stagnation surface, wherefrom inflows and outflows along magnetic field lines that thread the black hole event horizon…

High Energy Astrophysical Phenomena · Physics 2017-08-30 Hung-Yi Pu , Kinwah Wu , Ziri Younsi , Keiichi Asada , Yosuke Mizuno , Masanori Nakamura

It is widely believed that relativistic jets in X-ray binaries and active-galactic nuclei are powered by the rotational energy of black holes. This idea is supported by general-relativistic magnetohydrodynamic (GRMHD) simulations of…

High Energy Astrophysical Phenomena · Physics 2018-01-24 Michael O' Riordan , Asaf Pe'er , Jonathan C. McKinney

The large number of isolated black holes (IBHs) in the Galaxy, estimated to be 10^8, implies a very high density of 10^-4 pc^-3 and an average distance between IBHs of 10 pc. Our study shows that the magnetic flux, accumulated on the…

High Energy Astrophysical Phenomena · Physics 2012-11-26 M. V. Barkov , D. V. Khangulyan , S. B. Popov

To investigate the formation mechanism of relativistic jets in active galactic nuclei and micro-quasars, we have developed a new general relativistic magnetohydrodynamic code in Kerr geometry. Here we report on the first numerical…

Astrophysics · Physics 2009-10-31 Shinji Koide , David L. Meier , Kazunari Shibata , Takahiro Kudoh

We extend a recent work on weak field first order light deflection in the MOdified Gravity (MOG) by comprehensively analyzing the actual observables in gravitational lensing both in the weak and strong field regime. The static spherically…

General Relativity and Quantum Cosmology · Physics 2023-11-17 R. N. Izmailov , R. Kh. Karimov , E. R. Zhdanov , K. K. Nandi

We provide a semi-analytic comparison between the Blandford-Znajek (BZ) and the magnetic reconnection power for accreting black holes in the curved spacetime of a rotating black hole. Our main result is that for a realistic range of…

High Energy Astrophysical Phenomena · Physics 2018-07-13 Chandra B. Singh , David Garofalo , Elisabete M. de Gouveia Dal Pino

We present 3D general relativistic magnetohydrodynamic(GRMHD) simulations of zero angular momentum accretion around a rapidly rotating black hole, modified by the presence of initially uniform magnetic fields. We consider serveral angles…

High Energy Astrophysical Phenomena · Physics 2021-02-17 Sean M. Ressler , Eliot Quataert , Christopher J. White , Omer Blaes

Our modified gravity theory (MOG) is a gravitational theory without exotic dark matter, based on an action principle. MOG has been used successfully to model astrophysical phenomena such as galaxy rotation curves, galaxy cluster masses, and…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-25 J. W. Moffat , V. T. Toth

An explicit example is found showing how a modified theory of gravity can be constrained with the ringdown signals from merger of binary black holes. This has been made possible by the fact that the modified gravitational theory considered…

General Relativity and Quantum Cosmology · Physics 2019-10-23 Jiahui Bao , Changfu Shi , Haitian Wang , Jian-dong Zhang , Yiming Hu , Jianwei Mei , Jun Luo

Blandford-Znajek mechanism, by which the rotational energy of a black hole is extracted through electromagnetic fields, is one of the promising candidates as an essential process of the central engine of active compact objects such as…

Astrophysics · Physics 2008-11-26 Kentarou Tanabe , Shigehiro Nagataki

Exact solutions describing rotating black holes can offer important tests for alternative theories of gravity, motivated by the dark energy and dark matter problems. We present an analytic rotating black hole solution for a class of…

High Energy Physics - Theory · Physics 2018-04-10 Francesco Filippini , Gianmassimo Tasinato

We discuss the propagation of radiative MHD jets and outflows focusing on outflows driven by magneto-centrifugal rotators. Our goal is to link the properties of the jets with the physics of the sources which produce them. We find that…

Astrophysics · Physics 2007-05-23 Adam Frank , Thomas A. Gardiner , Thibaut Lery

The deflection angle of Kerr-MOG black holes is studied for different values of the parameter in modified gravity (MOG). To this end, we employ the Gauss-Bonnet theorem, which was first studied by Gibbons and Werner and then extended by…

General Relativity and Quantum Cosmology · Physics 2019-10-29 Ali Övgün , İzzet Sakallı , Joel Saavedra

Gravitational waves from binary black hole mergers provide a glimpse of gravitational dynamics in its most extreme observable regime, potentially enabling precision tests of general relativity (GR) and of the Kerr description of black…

General Relativity and Quantum Cosmology · Physics 2026-05-14 Ayush Roy , Lorenzo Küchler , Adam Pound , Rodrigo Panosso Macedo

We analyze the dynamical evolution of a perturbed force-free magnetosphere of a rotating black hole, which is described by the Blandford-Znajek solution in the stationary limit. We find that the electromagnetic field perturbations can be…

High Energy Astrophysical Phenomena · Physics 2014-11-26 Huan Yang , Fan Zhang

Modified gravity (MOG) is a covariant, relativistic, alternative gravitational theory whose field equations are derived from an action that supplements the spacetime metric tensor with vector and scalar fields. Both gravitational (spin 2)…

General Relativity and Quantum Cosmology · Physics 2018-03-14 M. A. Green , J. W. Moffat , V. T. Toth

A new class of modified gravity theories, made possible by subtle features of the canonical formulation of general covariance, naturally allows MOND-like behavior (MOdified Newtonian Dynamics) in effective space-time solutions without…

General Relativity and Quantum Cosmology · Physics 2023-11-01 Martin Bojowald , Erick I. Duque

A consequence of adopting a modified gravitational theory (MOG) for the aLIGO GW190521 gravitational wave detection involving binary black hole sources is to fit the aLIGO strain and chirp data with lower mass, compact coalescing binary…

General Relativity and Quantum Cosmology · Physics 2020-09-10 J. W. Moffat