http://scienceworld.wolfram.com/physics/BlackHole.html
Apparently, mass, charge and spin are the only ‘allowed’ properties. There is much talk of charged (aka “Reissner-Nordström”) black holes, so I suspect it works somehow, but I couldn’t find an epxlanation.
Ah, I feel slightly less ignorant then when I started the day. Thanks.
I’m also looking forward to the day when I can buy my electormagnetically suspended microblackhole-in-a-paperweight from the Sharper Image.
I just have this vision of Romulans mugging people for their paperweights…
Well, be careful with it. You’re going to have to feed it constantly and very meticulously to keep it from vanishing or flying away and eating the world. You might want to make sure you’ve got your lead apron on at your desk, too, as the thing will be radiating all the time at an intensity that could be dangerous with prolonged exposure.
The Enterprise’s matter/antimatter engine seemed pretty problematic in the event of a core breach, too.
More seriously, there’s some useful information about black holes and Hawking radiation here and here. We find some useful relations:
Temperature: T = (hbar c[sup]3[/sup])/(8 pi G k m)
Radius: r = 2 G m/c[sup]2[/sup]
Radiation power: P = K/m[sup]2[/sup], where K= 3.563 x 10[sup]32[/sup] W/kg[sup]2[/sup].
Lifetime: tau = c[sup]2[/sup]/(3 K) m[sub]0[/sub][sup]3[/sup]
Total energy output is of course E = m c[sup]2[/sup]
If our present theories are accurate, small black holes aren’t really very “black” at all.
For instance, unless I made an error in my calculations, a black hole with a mass of one kilogram would radiate energy with a power of 356 million million million million million watts. That would be rather difficult to store safely. By comparison, the most powerful hydrogen bomb ever detonated had a yield of about 60 megatons of TNT, or 2.4 x 10[sup]17[/sup] Joules. Our hypothetical 1 kg hole would release the energy of more than a quadrillion of these bombs every second.
This is somewhat deceptive, because this would only be the power radiated if the black hole remained a constant size. If left alone, it would explode completely after much less than a second. To keep it stable, we would need to feed new mass to this black hole just as quickly as it radiated away energy. This would take 4 quadrillion kg every second, or about the mass of 40 million aircraft supercarriers like the USS Nimitz. This might be difficult, since a 1 kg black hole would have an external radius on the order of 10[sup]-25[/sup] cm: about one 10-billionth that of a single proton.
At some intermediate scale a black hole would presumably be useful for completely converting mass into energy, assuming we could store it someplace where it wouldn’t accidently consume any planets. For instance, a more practical black hole that only needed to be fed a gram a second would have a mass of 2 billion kg. I don’t think this is the kind of thing we can expect a particle accelerator to produce anytime soon, and no natural stellar black holes will shrink to this size until we wait about 10[sup]70[/sup] years. Unfortunately, the rapid decline in power output with increasing mass really weighs against us here.