Black holes possible
The accelerator, known as the Large Hadron Collider, is under construction in an underground circular tunnel nearly 17 miles long at the world's largest physics laboratory, CERN, near Geneva.
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At its maximum, each particle beam the collider fires will pack as much energy as a 400-ton train traveling at 120 mph. By smashing particles together and investigating the debris, scientists hope to help solve mysteries such as the origin of mass and why there is more matter than antimatter in the universe.
If theories about the universe containing extra dimensions other than those of space and time are correct, the accelerator might also generate black holes, Landsberg and his colleague Savas Dimopoulos at Stanford University in California calculated in 2001. Physicists Steve Giddings at the University of California, Santa Barbara and Scott Thomas at Stanford University in California reached similar conclusions.
Black holes possess gravitational fields so strong that nothing can escape them, not even light. They normally form when the remains of a dead star collapse under their own gravity, squeezing their mass together. Although black holes can't be seen, astronomers infer their existence by the gravitational effects they have on gas and stars around them.
Making black holes
A number of models of the universe suggest extra dimensions of reality exist that are each folded up into sizes ranging from as tiny as a proton, or roughly a millionth of a billionth of a meter, to as big as a fraction of a millimeter.
At distances comparable to the size of these extra dimensions, gravity becomes far stronger, these models suggest. If this is true, the collider will cram enough energy together to initiate gravitational collapses that produce black holes.
If any of the models are right, the accelerator should create a black hole anywhere from every second to every day, each roughly possessing 5,000 times the mass of a proton and each a thousandth of a proton in size or smaller, Landsberg said.
Still, any fears that such black holes will consume the Earth are groundless, Landsberg said.
For one thing, theoretical physicist Stephen Hawking calculated all black holes should emit radiation, and that tiny black holes should lose more mass than they absorb, evaporating within a billionth of a trillionth of a trillionth of a second, "before they could gobble up any significant amount of matter," Landsberg said.