I'm just curious about one thing. Is it possible to make or create an artificial black hole?
In theory yes. All you would have to do is to put a large amount of energy in a small space, and you would have a black hole. It is however difficult (to say the least) to do that. The highest energy densities produced by mankind are the ones produced in particle physics experiments (elementary particles colliding at speeds close to the speed of light) but even those densites aren't even close to enough.
Creation of mini-black holes may be possible with the Large Hadron Collider, due to come on line within the next few years.
Though not technically a black hole, Dr. Mallet (UConn) is proposing the use of lasers to bend spacetime artificially. If he succeeds he'll have created the ability to bend spacetime back on itself just like a black hole does but without the annoying ridiculous amounts of mass required to sustain a 'normal' black hole. He's hoping to build a time machine with it... Guess we'll see in a few more years...
Does that mean this black hole won't have any gravitational pull like natural black holes?
Yup, that's my understanding dragonfly. It's probably incorrect to call it a black hole (for one, information will hopefully be extracted from it) but it's certainly a distortion of space-time, like we'd see in natural black holes.
I thought Brookhaven was supposed to have started theirs up already. Was it delayed? (funny side note...I peeked at Google for the answer and the first entry pointed me back to Physics Forums! We so totally rock. )
All is well at Brookhaven. The RHIC has been up a running for awhile now. Earlier this year they were smacking gold ions together at a whopping 200GeV. Unfortunately, no baby black holes have appeared, just your garden variety quark-gluon plasma.
There were some who thought 200 GeV might be enough to do the trick, most however believe it will take energies in the TeV range. The LHC will have this kind of muscle. Here are the stats for both colliders
RHIC ( Relativistic Heavy Ion Collider )
Name of Institute/Site: BNL
Location: Brookhaven , USA , Americas
Classification of Site: Accelerator under Construction
Type of Accelerator: Collider, Superconducting Technology
Applications: Nuclear Physics, High Energy Physics
Particles used: ions
Beam Energy: up to 100 GeV/nucleon
LHC ( Large Hadron Collider )
Name of Institute/Site: CERN
Location: Geneva , Switzerland , Europe
Classification of Site: Proposed Project
Type of Accelerator: Storage Ring, Superconducting Technology
Applications: High Energy Physics
Particles used: protons, Pb-ions
Beam Energy: 14 TeV protons, 1150 TeV Pb, center of mass
Beam Current: 540 mA protons
As you can see, the LHC will be taking all the kids lunch money when it gets cranking. This information is a bit dated. The RHIC is currently on line and the LHC is under construction.
In principle you can but practically you can not , because :
1. It is not the density which is important for a black hole, but it is the mass. You need a lot of mass.
2. Roughly the size of a black hole is given by GM /c2, for the mass of sun I think is is about 3 km.
3. For a black hole of observable size (let us say 1 cm) you need about 10 to power 25 kg mass, can you manage for that.
Are we sure this is a good idea?
If somehow the "black hole" could become persisitant, it probably would not be a very good idea. You can imagine a sub-microscopic black hole dropping into the earth and oscillating to an fro, slowly, slowly nibbling away...
... It would solve the "How do we dispose of Nuclear Waste?" problem!!!
But self-esteem ould probably drop all around the world. All that concentrated mass would cause everyone to gain quite a few llbs.
It would be awesome to see a artificially created black hole though. Especially if you watched bend a laser beam in a circle. just think how crazy that would be!
mini black holes
Few days back I was strongly opposing the idea of creating mini black holes on the earth and my main argument was that for creating black holes you need a lot of mass but that is not true. After reading the following article I came to know that the only condition to form black holes is that the colliding particles must get so close that the gravitational force between them is strong relative to the other forces.
read this article
Correct. Mass is not important, only mass density. The variable is the lifespan of blackholes is inversely proportionate to their mass. Black holes created in accelerators would evaporate almost instantly via Hawking radiation. ps: No need to worry about them swallowing the earth. Supernova routinely spit out atomic nuclei [cosmic rays] at far higher energies than we could ever create in accelerators.
An interesting example of another kind of Event Horizon, and the possiblity of studying a mechanism like Hawking Radiation in an earthbound analogue.
Sonic black-holes are physical analogues of space-time in which sound plays the role of light. The physical correspondance is near perfect, oddly enough, and a sonic BH should produce Hawking radiation (as phonons of course) but observing them in such an environment will stretch the skill of the experimentalists to the limit.
So true, but imagine the implications of direct observation of Phonon emission in line with predicitions abotu Hawking Radiation! I for one, would need new underwear. Besides, studying the EH of this BH is going to be a looooot easier than a gravitional BH. It may stretch their skills, but it's nothing compared to trying to take a peek at a stellar mass BH at this resolution.
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