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Lab-Made Fireball May Be a Black Hole
MoogMan writes "BBC News reports that a lab fireball may be a black hole.
From the article: "A fireball created in a US particle accelerator has the characteristics of a black hole, a physicist has said. The Brown researcher thinks the particles are disappearing into the fireball's core and reappearing as thermal radiation, just as matter falls into a black hole and comes out as "Hawking" radiation." More information available from the NewScientist article (subscription required)."
Actually, at scales this small gravity is not the dominating force (thats from the article). A gust of wind would literally blow the black hole apart. Its actually pretty interesting from a research perspective. You can see how black holes work, throw something in, see how it comes out, etc... The only thing though is that in order to have some real fun you really do need massive blackholes because then you can warp spacetime and have well defined event horizons etc...
Regards,
Steve
You will need: a microscopic black hole having enough mass not to evaporate instantly.
Actually: You need one big enough to evaporate more slowly than it absorbs matter on its trip. Given the tiny cross-section of even quite massive black holes and high radiation rates when they're small, this is a moderately large - and extremely massive - object.
The black hole will plummet through the ground, eating its way to the centre of the Earth and all the way through to the other side: then, it'll oscillate back, over and over like a might come to rest at the core due to the resistance of the matter it passes through, [...]
As it absorbs the matter it also absorbs its momentum. If it absorbs any non-trivial amount of material on its way through it doesn't get near the surface even on the high point of its first half-orbit.
[...] but it'll have riddled the planet full of holes long before then
Except very near the surface the planet will have collapsed the holes as fast as they form.
Also, it has to be moderately large by the time it gets to a near-stop at the core. While it's orbiting at about planetary diameter it's passing through lots of stuff. Once it's at the core it's depending on the pressure to push stuff to it. So it has to be big enough by then that the absorbtion from pressure beats the losses through hawking radiation.
But even if it evaporates it will have converted a significant mass to energy. Do this enough and something that wouldn't detectably affect the planetary radius could cause a LOT of volcanism - at some geologic time later when the heat makes it to the surface.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
It was my understanding that Hawking radiation is the emission of either a particle or antiparticle from a pair of the two generated just this side of the event horizon of a black hole, where the particle's partner falls into the event horizon and the particle floats on to live another day, appearing as radiation emitting from the black hole. The pair only comes into existence with a boost from the gravity of the black hole.
If this is done in a particle accelerator, which is a vacuum, and the objects with which we're dealing are gluons and other sub-atomic particles, how can their resultant mass be high enough to generate the requisite gravity for such a thing, and from where is the pair made in the vacuum?
At the least, shouldn't the other forces override the strength of gravity by an enormous amount?
This reminds me of something I saw from a while back, the idea of an optical black hole.
Basically, it has nothing to do with gravitational black holes, but the semi-hysterical press stories didn't pick up on that at the time either.
I'd explain it, but follow the link, or try this one for something clearer and simpler. I got these links from this search, but not all the results look relevant. Still, you may be able to find more, at least starting there.
Hmm, could you levitate a black hole against the force of gravity and feed it matter at a rate equal to its evaporation rate, then use the radiated energy as a heat source?
Would such a construct be a useful direct mass to energy conversion device? Or would it just irradiate all the mass in the vicinity, producing lots of radioactive crap to get rid of?
Now, the LHC (Large Hadron Collider), that's a different story. Here the energy density and black hole production cross sections are actually high enough, a black hole production signal could actually be measured.
Sadly, in all cases, the black holes evaporate harmlessly.
i\hbar\dot{\psi}=\hat{H}\psi