CHICAGO Doomsday predictions surrounding the start-up of Europe's Large Hadron Collider -- a giant particle-smasher designed to explore the origins of the universe -- come as little surprise to physicists.
The world's largest particle-collider has yet to begin experiments, but its trial run on Wednesday was accompanied by worries that it might spawn black holes with enough gravitational pull to swallow up the Earth.
Edward "Rocky" Kolb, chairman of the department of Astronomy and Astrophysics at the University of Chicago, says such fears come with the territory.
"This is an experiment at the frontier of our knowledge of nature. It is opening the door into uncharted territory," he said in a telephone interview. But Kolb feels awe, not fear.
"Rather than creating a black hole that destroys the universe, we expect to discover new laws of nature," he said.
A group calling itself the Citizens Against The Large Hadron Collider filed a lawsuit trying to halt the project and the father of a 16-year-old girl in India said his daughter killed herself on Wednesday after being traumatized by news reports of doomsday predictions.
So far, no particle smashing has taken place. Scientists have only circulated proton beams around the accelerator's giant 17-mile (27-km) tunnel on the French-Swiss border.
"The doomsday prophets would say they haven't had any collisions. They would say we are not out of the woods yet," said Kolb, who spent a year working at the European Center for Nuclear Research, or CERN.
"The reason I'm not concerned is that nature has already done this experiment. It was done in the early universe," Kolb said.
"Cosmic rays have hit the moon with more energy and have not produced a black hole that has swallowed up the moon," he said. "The universe doesn't go around popping off huge black holes."
Kolb and others said people made similar doomsday predictions before the opening of the Relativistic Heavy Ion Collider at Brookhaven National Laboratory in 1999.
Other physics experiments have engendered fear as well.
When Enrico Fermi was testing the first nuclear reactor in a squash court at the University of Chicago in 1943, some scientists worried that it could generate an explosion that might blow up the Chicago neighborhood of Hyde Park.
"Fermi had sort of a wicked sense of humor. He was taking bets at the test site about whether the world would end or not," Kolb said.
And he said some scientists predicted that the first atomic bomb would ignite all of the nitrogen in the Earth's atmosphere. "It turned out that calculation was wrong," Kolb said.