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This is an edited version--there's a lot more they hope to learn thanks to this machine--all of which is explained in the article here.GENEVA — Michelangelo L. Mangano, a respected particle physicist who helped discover the top quark in 1995, now spends most days trying to convince people that his new machine won't destroy the world. "If it were just crackpots, we could wave them away," the physicist said in an interview at the European Organization for Nuclear Research, known by its French acronym, CERN. "But some are real physicists."
What the critics are in such a lather about is the $8-billion Large Hadron Collider, a massive assemblage of iron, steel and superconducting wire 300 feet underground in a 17-mile-long circular tunnel on the Franco-Swiss border. The most complex piece of scientific equipment ever built, the collider will send particles crashing into each other at just a wink shy of the speed of light, generating energies more powerful than the sun. Scientists like Mangano believe that this instrument, when it begins operating as early as this summer, will peer into a looking-glass world that could contain entrances to extra dimensions and super-massive partners of the familiar particles that make up our world. One creature that must be hiding there, the scientists say, is the Higgs particle, one of the most exotic undiscovered objects since the yeti.
Critics think the collider could also spawn a black hole that will swallow Earth.
That could be just an appetizer. Once the collider got going, according to the doomsday scenario, it could gobble up distant stars like a child popping Skittles. Mangano, who is part of the CERN group studying the safety of the collider, doesn't deny the scant possibility that the collider could yield a mini-black hole. By smashing protons and lead ions together at energies reaching 14 trillion electron volts, the Large Hadron Collider will dwarf the world's other atom smashers, including the Fermi National Accelerator Laboratory's mighty Tevatron in Batavia, Ill. But that energy, Mangano hastened to add, would be concentrated in a space thinner than a human hair. Any black hole would be so tiny that it wouldn't be able to get its teeth around a bit of local chevre cheese, let alone the world. Still, if a black hole was produced at all, "that would be an extremely spectacular result," he said, a half-smile creeping across his face....
...The CERN collider uses a powerful electromagnetic field to accelerate particles. "Think of a swing," said Sandor Feher.... "Each time the beam comes around, the field pushes it a little faster." At the peak, the hydrogen protons in the new collider will reach 99.9999991% of the speed of light. Each packet of protons will complete 11,245 laps around the collider every second and carry as much power as a speeding train....Whatever objects spring into being in the collider won't last long. They will be relatively big and thus inherently unstable and will quickly decay into more-familiar particles. Some of these weird objects may travel as much as a millimeter or two before decaying, while others will travel less than the diameter of a proton before vanishing in a shower of quarks, gluons, electrons or neutrinos.
Because the detectors will produce millions of collisions every second, scientists will rely on huge clusters of computers to analyze the results. The computers will discard almost all the collisions, preserving only the most unusual for deeper analysis by humans....If all goes as planned, scientists say, the new collider is likely to become one of the greatest engines of discovery in history, far outstripping the Apollo moon missions and even Charles Darwin's monumental voyage aboard the Beagle. "This is the elevator that will take us to the next floor" of discovery, Mangano said.
...The huge burst of energy in particle collisions becomes a kind of time machine, transporting scientists back to the first microseconds after the Big Bang. The universe was only about 200 million miles wide, consisting of a viscous cloud of quarks and gluons floating in a searing plasma. As the universe expanded and cooled, the quarks combined to make protons and neutrons. The gluons held them together to form the nuclei of atoms. To re-create this plasma, one of the collider's detectors, known as ALICE, will accelerate heavy lead ions. One of the heaviest of all elements, each lead atom contains 82 protons and 125 neutrons. By pounding these sacks of protons and neutrons together, the scientists hope to free the quarks and gluons from their embrace into a free-floating quark-gluon plasma....
Then there's the matter of black holes. Harvey Newman, a Caltech physicist...said the collider could theoretically produce a mini-black hole by packing a tremendous amount of energy into a tiny space. But he said the black hole would pose no threat because it would last only 10-27 seconds before decaying -- hardly enough time to start gobbling up the French countryside. Critics are not convinced. Just last month, Walter L. Wagner and Luis Sancho filed suit in U.S. District Court in Honolulu to block the start-up of the new collider until CERN produces a comprehensive safety report. Speaking from Hawaii, Wagner said that despite assurances from scientists at CERN and around the world, there was no proof a mini-black hole would disappear. No one has ever seen it happen, said Wagner, who studied cosmic ray physics at UC Berkeley as a young man. It's just as possible that the tiny black hole would be stable and start chewing up normal matter, he said. It could take years for it to become large enough to gobble up the Earth, but there's no evidence that can't happen, he said. His suit for a restraining order is to "preserve the status quo while the court considers the arguments. In this case, the status quo is Mother Earth being here," he said.
Another nightmare possibility is that the collider could produce something called strange matter, a theoretical substance that some physicists think exists in the center of the remnants of collapsed stars. The pressure and temperature are so intense that the protons and electrons fuse into neutrons, then collapse into a mass of quarks. Theoretically, the tremendous gravity of strange matter would convert any ordinary matter it came in contact with. Mangano said he is now writing a report addressing such concerns. He said that protests of physics experiments were nothing new. "Before each new accelerator started, there has been some panic," he said. Wagner, in fact, filed suit in 1999 to stop Brookhaven National Laboratory's Relativistic Heavy Ion Collider in New York. It went ahead and the world survived -- just as it will this time, according to scientists from Mangano to Newman and Stephen Hawking....