From: Anders Sandberg (asa@nada.kth.se)
Date: Mon Dec 09 2002 - 14:51:52 MST
Ah, found a fun paper:
http://arxiv.org/PS_cache/astro-ph/pdf/0004/0004051.pdf
This explanation for quasars seems hopelessly optimistic, but has plenty
of interesting details about toroidal stars and black holes. The theorem
I was referring to earlier was the topological censorship theorem of
Friedman, Schleich & Witt 1993. I still consider these beasts a bit
unlikely, but what a wonderful universe it would be if they existed or
we could make them!
Some other related stuff:
http://www.math.ualberta.ca/~ewoolgar/pdfpapers/topcen.pdf
http://xxx.lanl.gov/abs/gr-qc/9903061
http://math.ucr.edu/home/baez/RelWWW/grad.html (LOTS of yummy stuff!)
On Mon, Dec 09, 2002 at 09:51:19PM +0100, scerir wrote:
>
> Perfect. Just to point out that the efficiency of transforming the
> mass-energy of a *non* rotating Reissner-Nordström EMBH (black hole
> endowed with e.m. structure) into particles-antiparticles pairs
> (essentially a e+ e- gamma plasma) in the 'dyadosphere' region,
> seems (after calculations at Livermore Red. Lab., by Remo Ruffini
> and Jim Wilson) to be >> 50% and very close to 100% (!), for black
> holes with mass between the mass of a neutron star and 10^6 M.
Yes, this is very useful. But isn´t this extraction process only for the
electrical part of the mass-energy? I thought it ended up with a boring
schwarzschild hole after the charges had been neutralized.
-- ----------------------------------------------------------------------- Anders Sandberg Towards Ascension! asa@nada.kth.se http://www.nada.kth.se/~asa/ GCS/M/S/O d++ -p+ c++++ !l u+ e++ m++ s+/+ n--- h+/* f+ g+ w++ t+ r+ !y
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