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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
insightful? he copied that from the article. sheesh.
now we get modded up for copying one sentence in the text, not just the entire article.
** "It's not my job to stand between the people talking to me, and the ones listening to me." -- Pego the Jerk
Looks like he was a bit early, though.
In the fall of 2001, after John left, CERN issued a press release...
Not sure if the actual statement from him said that they would do it within a year or they would "make an announcement pertaining to this" but if it's indeed the latter, I'd say the "prediction" was satisfied for whatever that is worth. Now it's (possibly) been done, so I guess you could also say that CERN's "prediction" happened also.
Seems Titor's technique was to pick up on some things that were just coming into the fringe of the public eye but not really making significant news yet and then make a prediction that just basically said "this will be a big deal in a few years". Although this is not terribly hard to do, the fellow did it very well and has hitherto been pretty lucky about his choices.
A Titor of today would probably choose to make sweeping predictions regarding the economic growth of China and the looming energy crisis it will cause. He might make some bold declaration about nuclear power coming back into vogue
Some of his statements were a little too bold and forward looking, though. Tthe US goes into civil war this year according to Titor; however, historically the US political system has survived many tragedies larger than an economic slump or bad apples in power. He also had said that medicine takes a big step backwards and medical advancement slows, which is also historically highly unlikely. If there is all this crisis going on, then historically, medical advancement INCREASES during times of long crisis. Perhaps Titor did not do enough study of history before making some of his predictions. Unfortunately for him, the few bold and horribly wrong predictions will probably collapse the credibility of the hoax. Other than that, it might have been a pretty good one.
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?
David Brin is great, and Earth is probably the most relevant story to this news, as part of its plot involves a man-made black hole. Besides the black hole stuff, it's a great attempt at a 50-year prediction. 50-year predictions are tricky because they need some big leaps but nothing too discontinuous, and cool because they're a time frame that a lot of us might live to see tested.
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?
Actually, the interesting thing is that we only have theories about black holes, no direct evidence. Not only that, but black holes push the boundaries of our understanding of physics. AFAIK, we've never directly observed hawking radiation, and so we don't even know that it has to exist. We only theorize that it really should because it fits what we know so far of relativity and quantum mechanics.
So, if they actually did manage to create a small black hole, and then it evaporate, we have our first direct evidence that hawking radiation is real.
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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