Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Brandon Guerrero on 07/02/2009 10:54:31
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Brandon Guerrero asked the Naked Scientists:
I hear that the Fermilab's Tevatron can possibly generate microscopic black
holes. If so.. Could they increase in size?
What do you think?
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Brandon Guerrero asked the Naked Scientists:
I hear that the Fermilab's Tevatron can possibly generate microscopic black
holes. If so.. Could they increase in size?
What do you think?
If it generates black holes then they will very probably last only a tiny fraction of a second, so they wouldn't have time to grow. At least this is what scientists have told us...
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I agree with lightarrow. My guess is that it can not produce black holes. So I would also guess that they would not grow. The energy of collision of any man made device that we have today is less than that produced by many cosmic rays. Cosmic rays are hitting our atmosphere constantly and have been doing so since the earth came into existance.
So if particle collision could make toast of us we would have been toast long ago[:)]
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What's a Tevatron, for those not in the know?
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The tevatron is the current largest particle collider in the USA similar to the LHC but less powerful.
Very small black holes radiate very energetically assuming that Hawking radiation from event horizons applies which seems very likely for a black hole to survive and grow it in a given environment it needs in effect to be cooler than that environment. this can easily be checked by the hawking radiation calculator website
http://xaonon.dyndns.org/hawking/
for a 300 degree K black hole you would need about 4x10^17 metric tons of material
for one as hot as a star (6000K ) you need 2x10^16 metric tons, not much less. It is interesting to note that such a black hole would be about the size of an atom and only radiate about one microwatt
This is one hell of a lot of mass. Any black hole created by the tevatron would evaporate pretty quickly.
It has been suggested that the LHC might collide lead nuclei in the future so the largest possible hole they could make is about 400 atomic mass units which is about 1x10^-21 of a gram! Such a black hole is less than the Planck mass could only last less than the Planck time.
I consider that the possibility of creating a black hole with the tevatron LHC or any human constructed device in the foreseeable future is so small as to be impossible and is well into the "Greg Bear" scale of technology.
To create a useful sized black hole it would be necessary to take several carefully shaped mountain sized asteroids and launch them at near light velocities in a precisely spherical arrangement so that they all collided at exactly the same instant. This could in theory create a power source that would last for ages but it would of course take more energy input to create than you could ever get out of it.
Stellar mass black holes are just about the smallest that can be practically created in our universe at the moment.
However that does not mean that in the early stages of the big bang smaller black holes might have been made.