Hey Tao!
I started to post a few thoughts about the inner workings of a black hole and how rotation would expedite the process, and somehow I clicked the wrong button and lost about a half hour's writing. I'm beat, I'll have to try again later if I don't lose my thought. Sorry.
In the meantime, here's a little bit to whet your appetite:
Collimated Energy-Momentum Extraction from
Rotating Black Holes in Quasars and Microquasars Using the Penrose Mechanism
Authors: Reva Kay Williams (University of Florida)
Comments: 9 Latex pp., including 3 eps figs. (aipproc.sty macros), to appear in proceedings, 20th Texas Symposium on Relativistic Astrophysics (10-15 December 2000), edited by J.C. Wheeler and H. Martel, in press
For almost four decades, since the discovery of quasars, mounting observational evidence has accumulated that black holes indeed exist in nature. In this paper, I present a theoretical and numerical (Monte Carlo) fully relativistic 4-D analysis of Penrose scattering processes (Compton at radii between the marginally stable, marginally bound orbits and gamma-gamma-->$e^-e^+$ pair production at the photon orbit) in the ergosphere of a supermassive Kerr (rotating) black hole. These model calculations surprisingly reveal that the observed high energies and luminosities of quasars and other active galactic nuclei (AGNs), the collimated jets about the polar axis, and the asymmetrical jets (which can be enhanced by relativistic Doppler beaming effects) all are inherent properties of rotating black holes. From this analysis, it is shown that the Penrose scattered escaping relativistic particles exhibit tightly wound coil-like cone distributions (highly collimated vortical jet distributions) about the polar axis, with helical polar angles of escape varying from $0.5^o$ to $30^o$ for the highest energy particles. It is also shown that the gravitomagnetic (GM) field, which causes the dragging of inertial frames, exerts a force acting on the momentum vectors of the incident and scattered particles, causing the particle emission to be asymmetrical above and below the equatorial plane, thus appearing to break the equatorial reflection symmetry of the Kerr metric. This energy-momentum extraction model can be applied to any size black hole, irrespective of the mass, and therefore applies to microquasars as well.
setting the record straight on black holes
SELECTED PUBLICATIONS
Williams, R. K.,`Extracting X-Rays, Gamma-Rays, and Relativistic Electron-Positron Pairs from Supermassive Kerr Black Holes Using the Penrose Mechanism, Physical Review D, 51, No. 10, 5387-5427 (1995).
Williams, R. K., `Production of the High Energy-Momentum Spectra of Quasars 3C 279 and 3C 273 Using the Penrose Mechanism, submitted to The Astrophysical Journal May 1995; resubmitted May 1999; accepted.
Williams, R. K., Penrose Processes and the Gravitomagnetic Field, in The 8th Marcel Grossmann Meeting On Recent Developments in Theoretical and Experimental General Relativity, Gravitation, and Relativistic Field Theories, Proceedings of The 8th Marcel Grossmann Meeting, held at The Hebrew University, Jerusalem, Israel, 22-27 June 1997 (eds. Piran, T. and Ruffini R.) 416-418 (World Scientific, Singapore. 1999).
Williams, R. K., Extracting Energy-Momentum from Rotating Black Holes Using the Penrose Mechanism, Bulletin of the American Physical Society, 44, No. 6, 35 (1999).
Williams, R. K., High Energy-Momentum Extraction from Rotating Black Holes Using the Penrose Mechanism, Bulletin of the American Astronomical Society, 31, No. 5 (1999).
Reva Kay Williams