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Particle Collider Fires, No Black Holes Form

Scientists fire up the world's largest particle collider in Switzerland, but fears about the experiment creating black holes that could devour the Earth and other planets are not realized.

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These protons whizzing through the pipe and around the track? They travel in bunches. These bunches are inches long and half the width of a human hair. Each bunch contains 100 billion protons, give or take a few. Each beam carries about 3,000 bunches. They travel at 99.9999991 percent the speed of light. So they are able to complete 11,245 laps a second. In 10 hours of operation, the beam could travel to Neptune and back.

The beams will travel on parallel tracks until the moment of truth. Then, at four major intersections along the way, the beams will cross and collide. The crash sites are the business end of the machine. That is where they put the detectors.

"Think of oranges," Evans said. "You collide two oranges together, you get a lot of pulp. We're not so interested in the pulp. What we want to do is see what happens when the pips -- the seeds -- hit each other." The proton is the orange, its component quarks are the pips.

And how many times will these pips collide? That would be 600 million collisions a second. The good head-on-smashup will erupt into a cloud of scattering particles, and the detectors (and their computers) will attempt to record the trajectories, energies, speeds, decays.

That's a lot of data to record.

"Quite," Evans said.

In one of the very useful cartoon books produced by the CERN public relations staff, an illustration shows a stack of 3 million CDs that is equal to the data flow from a year's worth of collider experiments. It is 12 miles tall.

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To understand, deeply, some of the things the scientists here are talking about is not really possible. "I don't understand, fully, the math involved in the string theories," confessed Robert Cousins, a UCLA physics professor working at CERN on the Compact Muon Solenoid experiment.

But the general idea is this. "Humans have always asked, 'Where do we come from?' " Cousins said. "And this is the way that physicists ask that question."

For example, astrophysicists have observed that visible matter accounts for only 4 percent of the universe. By looking at gravitational effects -- for instance, how fast galaxies spin -- they can guess that there is more stuff out there than they can see. But what is this "dark matter?" Could dark matter be composed of "supersymmetric" particles, which might pop up in the collisions at CERN? For this reason, some people have called the Large Hadron Collider the "Hubble telescope of inner space."

And what about the mystery of antimatter? Antimatter is the identical-but-opposite twin of matter, except that for some unknown reason, nature prefers matter. As Cousins explained, if the universe and nature were neat and tidy, then equal amounts of matter and antimatter would be present at the Big Bang. But something is missing. The universe appears to be constructed entirely of matter. Where did all the antimatter go? "There is an imbalance," Cousins said. "So what gives?"