BOSTON — With a few pen strokes, the United States today becomes a significant player in building the world's most powerful time machine.
The $6 billion project, known as the Large Hadron Collider (LHC), will be built along the Franco-Swiss border. It aims to duplicate the enormous energy levels thought to have existed during the first trillionth of a second after the universe burst into existence in the "big bang."
In re-creating these conditions, scientists expect the LHC to help answer basic questions about properties of matter and the evolution of the universe. It should begin operating in 2005.
"We're really excited about this," says Martha Krebs, director of energy research at the US Department of Energy, echoing the sentiments of particle physicists around the country.
Many of them still mourn the loss in 1993 of a much more powerful collider that was being built in Texas. Congress stopped funding the program out of concern for its ballooning costs and an uncertain return on what was to be a $10 billion investment.
Today's agreement ensures that the US "continues to participate at the energy frontier, doing discovery-level physics," says Daniel Green, a physicist at the Fermi National Accelerator Laboratory (FNAL) in Batavia, Ill., and technical director for one of the LHC's four large-particle detectors.
The pact between the US and the European Laboratory for Particle Physics (CERN) near Geneva calls for the US to spend $531 million to design and build components for the LHC and its detectors. Of that, $90 million is earmarked specifically for buying superconducting materials and other hardware from US companies.
The LHC project represents the first time the US has contributed to a world-class collider overseas.
This helps cement the project's standing as the first truly global science facility, according to Robert Eisenstein, assistant director for mathematical and physical sciences at the National Science Foundation in Washington. The project involves 4,000 scientists and engineers in 45 countries.
"International collaboration is the current buzz word," he says. "I'm very excited about this agreement."
The collider is designed to send two beams of protons hurtling in opposite directions through a ring 27 kilometers (16.78 miles) around. Superconducting magnets chilled to 2 degrees above absolute zero will steer the beams, focus them, then force them to collide. When they do, the protons will smack together with an energy level of 14 billion electron-volts. That's not much - about the amount of energy 14 mosquitoes use to flap their wings. But in the tiny world of subatomic particles, that level is cataclysmic.
Researchers using the LHC are interested in answers to basic questions such as what gives a particle of matter, like a proton or quark, its mass? The reigning notion holds that a particle's mass comes from its interaction with a force field that is present everywhere, known as the Higgs field. The calculations that gave rise to this theory also predict that the field has a corresponding particle, or particles, that should become evident at energy levels the LHC is designed to attain.
Collisions at the LHC also could help account for the universe's "missing" mass. The amount of mass in the universe determines whether it will continue to expand forever, or collapse back on itself. One idea holds that the missing matter consists of stable, but as yet undiscovered, particles and that these particles exist within the LHC's energy range.
Yet if and when these and other questions are answered, even more-powerful particle colliders will be needed as physicists look to validate their theoretical attempts to demonstrate that the forces of nature today are manifestations of one unified force that held sway at the earliest point in the universe's history.
"Future accelerators are going to be even bigger and more expensive," says Peter Limon, head of the technical division at FNAL. "Cost-sharing will be the only way to build them. This agreement marks the tentative beginning of global collaboration for big accelerators."
But the defense strategy so far has succeeded in keeping the spotlight off Nichols. As witnesses take the stand and proceed with lengthy accounts of what McVeigh and various associates were doing, Nichols seems scarcely visible in the courtroom. Indeed, without his presence at the defense table, one might overlook the fact that he alone is standing trial as co-conspirator in the bombing that claimed 168 lives.
While speculation about other co-conspirators may not help Nichols in the guilt phase, Mr. Lane believes the defense is making the most of this testimony now in anticipation of the penalty phase.
"I think, certainly, that the defense is gearing toward a penalty phase," he says. "When you have a death-penalty case, you have to proceed with this in mind from the outset. It's possible that this may create enough doubt for jurors when it comes to the penalty phase."
And although some evidence continues to link McVeigh and Nichols to militias, raising the question of how many people knew about the plot, experts predict that broader conspiracy theories aren't likely to appear during the trial. Judge Richard Matsch barred such testimony from McVeigh's trial, and "I would expect Matsch to be consistent with his earlier ruling," says Mr. Pizzi.