PHYSICS: BOSONS' BOSSES

By Natalie Angier

Carlo Rubbia was in a Milan cab, en route to Linate Airport last week and worrying about a possible Italian air-traffic controllers' strike. Suddenly the pop music on the taxi's radio was interrupted by a news bulletin: Rubbia and Simon van der Meer, his colleague at CERN, the great European nuclear research complex, had been jointly awarded the Nobel Prize for Physics. At first the taxi driver did not believe his passenger's excited claims to be the man in the news. "But when I convinced him," Rubbia recalls, "he offered me a free ride."

That the physicist learned of his prize in transit was fitting. Known among his friends as "the Alitalia scientist," Rubbia, 50, frequently flies from CERN, located outside Geneva where he does his research, to Harvard University in Cambridge, Mass., where he teaches physics. His relentless energy and aggressive pursuit of ideas are what led to his discovery of three critical subatomic particles, ending a 20-year hunt that involved hundreds of scientists.

Rubbia's find represented a great leap forward in science's attempt to prove the so-called unified field theory, which would link the four forces of nature in a single elegant set of equations. Two of those forces are familiar: electromagnetism, which lights bulbs and makes clothes cling; and gravity, which holds humans to the ground and determines the earth's orbit around the sun. The remaining two are more exotic: the so-called strong force, which binds together the particles in a nucleus; and the weak force, which controls radioactive decay.

Scientists believe that all four forces are manifestations of one fundamental superforce, which split into different forms after the birth of the universe. Some physicists had proposed that electromagnetism and the weak force, for example, might be combined, but their complex theory required the existence of three extremely heavy particles to complete the profile of the weak force: the positive W boson, negative W boson and Z boson. Rubbia decided to chase them down.

At CERN's fourmile, $400 million super proton synchrotron, Rubbia devised a method of creating supercollisions among subatomic particles that would, he predicted, produce the carriers of the weak force.

At first nobody believed his proposal, particularly since it would require the conversion of the synchrotron into a particle collider, at a cost of $55 million. Rubbia's notions, however, had one staunch supporter: Simon van der Meer, a senior engineer at CERN. Van der Meer designed a device critical to the taming of the colliding beams in Rubbia's experiment. In 1979 CERN gave Rubbia and Van der Meer a go-ahead for their project, and by 1983 the three particles had been found.

The flamboyant Rubbia, born in Gorizia, Italy, is certain to enjoy his half of the approximately $195,000 prize. He owns a yacht and has a hearty appetite, particularly for Italian food. He is impatient with lesser minds than his and is intellectually restless: his current projects range from tracking down the magnetic monopole, another elusive particle, to searching for antimatter.

The Dutch-born Van der Meer, 58, who once worked for Philips Electronics as a research scientist, is the very opposite of Rubbia. He is self-effacing and calm; winning the Nobel does not noticeably excite him, although he admittedly wanted it. Says he: "Let us say that I didn't exclude it, yet I did not dare to hope we'd get it." --By Natalie Angier. Reported by Robert Kroon/Geneva

With reporting by Robert Kroon