The particle physicists predict the world's new highest-energy atom smasher, the Large Hadron Collider (LHC) near Geneva, Switzerland, might create tiny black holes. Earlier it could not be shown that the prevailing theory of gravity, Einstein's theory of general relativity, predicts the formation of black this way. Now a computer model shows conclusively for the first time that a particle collision really can make a black hole.
The key to forming a black hole is cramming enough mass or energy into a small enough volume, as happens when a massive star collapses. According to Einstein's theory of general relativity, mass and energy warp space and time or space-time, to create the effect we perceive as gravity. If a large enough mass or energy is crammed into a small enough space, that warping becomes so severe that nothing, not even light can escape. The object thus becomes a black hole. Two particles can make a miniscule black hole in just this way if they collide with an energy above a fundamental limit called the Planck energy.
Choptuik and Frans Pretorius of Princeton University simulated such collisions, including all the extremely complex mathematical details from general relativity. They modeled the two particles as hypothetical objects known as boson stars, which are similar to models that describe stars as spheres of fluid. Using hundreds of computers, Choptuik and Pretorius calculated the gravitational interactions between the colliding particles and found that a black hole does form if the two particles collide with a total energy of about one-third of the Planck energy, slightly lower than the energy predicted by hoop conjecture, as they report in a paper in press at Physical Review Letters.
Although Choptuik says that the LHC is unlikely to make black holes, the research in this area should be immediately stopped even if there is slightest, remotest possibility.
Ref: Colliding Particles Can Make Black Holes, by Adrian Cho, ScienceNOW Daily News, 22 January 2010
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