Last October, when the House of Representatives voted to cut off funding for the 54-mile-round Superconducting Supercollider in Texas, it killed what was to have been the world's largest accelerator--one of those colossal machines designed to examine the behavior of subatomic particles by racing them to near light speed around enormous underground tracks. The attention of the disappointed physics community reverted to the current world champion, the Large Electron Positron collider, or LEP, which occupies a 17-mile tunnel under the Jura Mountains near Geneva, Switzerland.
LEP's name notwithstanding, size is just about the least significant attribute of a particle accelerator.
Depending on the questions accelerators are designed to address, a number of much more relevant criteria give other machines the edge over LEP. In fact, even as the mammoth project in Texas is winding down, accelerator builders in Virginia are putting the finishing touches on a device that is no larger than a horse racetrack. It is known as the Continuous Electron Beam Accelerator Facility, or CEBAF, and it is finally being switched on this summer after 15 years of planning and construction. If all goes well, experiments will begin in the fall. In terms of brute strength, CEBAF is 25 times feebler than LEP, but by another measure it is 1,000 times more potent. It all depends on how you define the prowess of an accelerator.
To compare the values of things, we assign numbers to them: price measures economic worth; grades, academic competence; diameter, the power of telescopes (the bigger the better); and resolution, the effectiveness of microscopes (the smaller the better). Indeed, in our digitally besotted age, the habit of evaluation by numbers has become so ingrained that athletic performance is reduced to a computer ranking, and political clout to an approval rating. But the most egregious oversimplification of this kind, the attempt to capture something as gloriously complex as human intelligence by means of a single number called the IQ, started long before the advent of the computer age.
