But on Wednesday, CERN scientists will first try to thread a single bunch of two billion protons through the collider.
"We will have a very low-intensity beam, so [in case of a problem] we can lose the beam without damaging the machine," Manglunki said.
Once the team gets the beam circulating all the way around the tunnel—which may happen in a couple of hours—the scientists will send in several bunches at a time.
Getting the first beam circulating, Manglunki said, is "one step in a very big staircase"—the long process of conceiving, designing, building, and finally running the experiment.
(See: "Broken Magnet Highlights Largest Collider's Engineering Challenges" [April 13, 2007].)
Although the physicists have done various tests on the machine already, "ultimately it's the beam that can tell you if everything is working," he added.
Later, they will attempt to get another beam of protons circulating through the tunnel in the opposite direction—a prelude to colliding the two beams.
Dark Matter Particle
In addition to spotting the Higgs boson, another early reward could be evidence of supersymmetry. The supersymmetry theory says that all the particles known today have much more massive—and as yet undetected—partners.
"There are strong reasons to believe that these new particles include the particle that makes up the cosmic dark matter that accounts for 80 percent of the matter in universe," said Michael Peskin, a particle physicist at the Stanford Linear Accelerator Center in Menlo Park, California.
(Related: "Dark Matter Proof Found, Scientists Say" [August 22, 2006].)
The collisions could also create a zoo of new particles, experts say.
"If any of these theories are right, the LHC should be turning up the evidence for these particles by next summer," Peskin said.
But there could also be some big surprises.
"It might turn out to be like the 1950s, when we were discovering many new particles and had no clue about how they fit into a coherent picture," Peskin said.
"I hope it will turn out like that," he added. "This is what makes science fun."
No Cause for Alarm
Some people are worried that the experiments could also create unwelcome discoveries, such as particles and other exotic phenomena that could swallow up Earth or destroy the universe as we know it.
For instance, one possibility is that the collisions will pack matter together so tightly that it may collapse to form miniature black holes.
But reviews by both CERN physicists and independent researchers argue that, even if such black holes do form, there's no reason for alarm.
"Collisions just like those the [atom-smasher] will make have been produced by cosmic rays bombarding the Earth throughout its existence," said a statement from the American Physical Society.
The most energetic cosmic rays are particles that pack much more energy than those in the Large Hadron Collider—so much so that physicists still aren't sure how the most powerful cosmic rays get created. (See: "Black Holes Belch Universe's Most Energetic Particles" [November 8, 2007].)
Steve Giddings, a physicist at the University of California, Santa Barbara, is actually hoping miniature black holes do show up, along with other evidence supporting string theory—an unproven theory that describes subatomic particles as though they are tiny vibrating strings.
"It would be extremely exciting to see string properties directly. And that is possible if there are extra dimensions of space that are configured just the right way," Giddings said.
"[Seeing] all of this would be the ultimate jackpot scenario."
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