In fact, using the results of Ref. The BL components are the same, since the orbit lies at constant r. The finite terms are needed if the energy and angular momentum are computed directly using the 4-velocity. The limiting frequency shift factor of a photon emitted from the ISCO in the transverse direction, i. By this redshift a distant observer could in principle infer that the orbit coincides with the horizon in the extremal limit.
The 4-velocity of that frame also stretches to an infinite vector and approaches the horizon generator, so the fact that this relative velocity is less than 1 is not inconsistent with the ISCO approaching the speed of light. Now let us examine the distance between the orbits on a BL slice.
Then we have. In conclusion, the orbits both coincide and do not coincide, depending on where they are examined. This is possible since in the extremal limit there is an infinite stretching of the spacetime region outside the horizon along a constant BL time slice 5 5 5 The extremal metric in the neighborhood of the bifurcation surface is written in Ref. For that metric one can show that there are marginally stable orbits at all radii, all with the same energy and angular momentum as that of the extremal ISCO.
I thank E. Barausse, A. Buonanno, and E. Poisson for useful comments on a draft of this paper. If you find a rendering bug, file an issue on GitHub. Piran, J. Shaham, High efficiency of the Penrose mechanism for particle collisions.
Banados, J. Silk, S. West, Kerr black holes as particle accelerators to arbitrarily high energy. Guo, S. Gao, Kerr black holes as accelerators of spinning test particles.
D 93 8 , Berti, R. Brito, V. Cardoso, Ultrahigh-energy debris from the collisional Penrose process. Schnittman, Revised upper limit to energy extraction from a Kerr black hole. Zhang, J. Jiang, Escape probability of particle from Kerr—Sen black hole.
B , Igata, K. Kohri, K. Ogasawara, Photon emission from inside the innermost stable circular orbit. Porfyriadis, A. D 90 4 , Fransen, T. Hertog, J. Long, Gravitational waves from plunges into Gargantua. Quantum Gravity 35 10 , Castro, V. Godet, J. Song, B. Lupsasca, M. Rodriguez, A. Strominger, Force-free electrodynamics around extreme Kerr black holes.
JHEP 12 , Gralla, A. Lupsasca, Force-free foliations. D 94 12 , Porfyriadis, Y. Shi, A. Strominger, Photon emission near extreme Kerr black holes. D 95 6 , Lupsasca, A. Strominger, Observational signature of high spin at the event horizon telescope. Shi, Critical emission from a high-spin black hole. D 97 6 , Ogasawara, T.
Igata, T. Harada, U. Miyamoto, Escape probability of a photon emitted near the black hole horizon. D 4 , Nakashi, K. Ogasawara, Observability of the innermost stable circular orbit in a near-extremal Kerr black hole. Gates, S. Hadar, A. Lupsasca, Photon emission from circular equatorial Kerr orbiters.
Lupsasca, Maximum observable blueshift from circular equatorial Kerr orbiters. D 10 , Jiang, Emissions of photons near the horizons of Kerr—Sen black holes.
D 12 , Cardoso, F. Duque, A. Foschi, The light ring and the appearance of matter accreted by black holes. Bardeen, G. D 60 , Reynolds, Measuring black hole spin using X-ray reflection spectroscopy. Space Sci. Miller-Jones et al. Science , — Guo, P. Li, B. Chen, Photon emission near Myers—Perry black holes in the large dimension limit. D 2 , Guo, N. Obers, H. Yan, Observational signatures of near-extremal Kerr-like black holes in a modified gravity theory at the Event Horizon Telescope.
D 98 8 , Yan, Influence of a plasma on the observational signature of a high-spin Kerr black hole. D 99 8 , Song, H.
Yan, Observational signature of a near-extremal Kerr—Sen black hole in the heterotic string theory. Thorne, Disk accretion onto a black hole. Evolution of the hole. Kapec, A. Lupsasca, Particle motion near high-spin black holes.
Quantum Gravity 37 1 , Strominger, Gravity waves from extreme-mass-ratio plunges into Kerr black holes. D 90 6 , Porfyriadis, N. Warburton, Particle on the innermost stable circular orbit of a rapidly spinning black hole. A large class of spherically symmetric static extremal black hole spacetimes possesses a stable null photon sphere on their horizons.
For the extremal Kerr-Newman family, the photon sphere only … Expand. View 3 excerpts, cites background. Particle on the innermost stable circular orbit of a rapidly spinning black hole. We compute the radiation emitted by a particle on the innermost stable circular orbit of a rapidly spinning black hole both a analytically, working to leading order in the deviation from … Expand.
Astronomical observation suggests the existence of near-extreme Kerr black holes in the sky. Properties of diffeomorphisms imply that dynamics of the near-horizon region of near-extreme Kerr are … Expand. Particle motion near high-spin black holes. General relativity predicts that the Kerr black hole develops qualitatively new and surprising features in the limit of maximal spin. Most strikingly, the region of spacetime near the event horizon … Expand.
View 1 excerpt. Innermost stable circular orbit near dirty black holes in magnetic field and ultra-high-energy particle collisions. The cases of near-extremal, extremal, … Expand. We consider a particle moving towards a rotating black hole.
We are interested in the number of its revolution n around a black hole. In this Chapter we provide the general framework for curved spaces and introduce the notions of Lorentzian geometry which are necessary for understanding the mathematical aspects of general … Expand.
New form of the Kerr solution.
0コメント