Sometime within the next few weeks, a team of physicists and engineers plan to settle into position in a control room at the Large Hadron Collider (LHC), the world's most powerful particle accelerator, on the outskirts of Geneva. They'll enter a series of commands into their computers, directing trillions of protons to begin moving through a series of exotic-sounding machines--a linear accelerator, a proton synchrotron, a super proton synchrotron--that add speed at every step.
The particles will be split in two groups and sent whirling in opposite directions around an oval tunnel more than 16.5 miles (26.5 km) in circumference and...