2019/04/28 by Isao Okamoto, Okamoto, Isao, Yoogeun Song +1
Engineering · Physics and Astronomy · #Astrophysical Phenomena and Observations #Astrophysics of Galaxies (astro-ph.GA) #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #Geophysics and Sensor Technology #High Energy Astrophysical Phenomena (astro-ph.HE) #Pulsars and Gravitational Waves Research
paper · pdf · doi:10.48550/arxiv.1904.11978
openalex publication_date 2019/04/28 · openalex created_date 2022/07/29 · openalex updated_date 2026/07/28
It is shown that when only the condition 0<Ω\rm F<Ω\rm H is satisfied, the Kerr black hole frame-drags its surrounding force-free magnetosphere with the field-line-angular-velocity (FLAV) Ω\rm F, where Ω\rm H is the horizon angular-velocity. Then, the zero-angular-momentum-observers (ZAMOs) circulating with the frame-dragging-angular-velocity ω will see that the `null surface' S\rm N where ω\rm N=Ω\rm F always exists. They will see that the outer domain D\rm (out) outside S\rm N is prograde-rotating with Ω_\rm F ω>0, whereas the inner domain D\rm (in) inside is retrograde-rotating with Ω_\rm F ω<0, where Ω_\rm F ω=Ω\rm F - ω denotes the ZAMO-FLAV. `This surface' S\rm N must be the magneto-centrifugal divider of the force-free magnetosphere, with a kind of plasma-shed on it. Subsequently, the force-free and freezing-in conditions break down on S\rm N, thereby allowing the particle-current sources to be set up on S\rm N. `This surface' also is the ZAM-surface S\rm ZAMD, on which no flow of angular momentum nor electric current can cross. Because the electric field \bf E\rm p reverses sign on S\rm N, the Poynting flux reverses direction from outward to inward on S\rm N. An electromagnetic self-extraction of energy will be possible only through the frame-dragged magnetosphere, with the inner domain D\rm (in) nested between the horizon and `this surface' S\rm N, in order to comply with the first and second laws of thermodynamics.