On July 4 a team of scientists announced the discovery of the Higgs particle at the Large Hadron Collider in Geneva, Switzerland. The effort to find the Higgs was prodigious: It took a decade, 10,000 scientists and engineers, and $10 billion to build the collider and the particle detectors that went into it. The result was a 17-mile ring that accelerates protons to nearly the speed of light, sends them in opposite directions around the ring and then smashes them into each other. The ensuing spew of particles is analyzed by two detectors called ATLAS and CMS. Each machine is comparable in size to Notre Dame cathedral and collects and analyzes data at a rate that would fill 100,000 CDs every second.
Is all this just expensive navel gazing?
Ten billion dollars is a lot of money, even if it was spread over a dozen countries and 10 years. But we should remember that it cost about the same to build the Atlanta airport expansion, mount the London Olympics or run the U.S. military for five days.
Besides, what is today's fundamental and obscure research is often tomorrow's corporate profit. Think of electricity in the 1850s, nuclear power in 1945 or the transistor in 1947. In fact, the World Wide Web was created at the collider's host lab in 1989 to deal with the flood of information being produced by its experiments. Even Einstein's General Theory of Relativity, often thought of as the height of arcane, high-brow philosophizing, has found use in the GPS navigational system.
Alas, it seems unlikely that the Higgs particle will ever be as useful as these discoveries. What the Higgs gains us is more ethereal, but just as worthy. To understand why, we need to go back 2,600 years to the ancient Greeks when Thales of Miletus initiated a long string of Greek inquiry into the nature of things.
One of the topics Thales and his intellectual descendants wrestled with was the nature of matter. One could, for example, imagine pounding rock into gravel, pulverizing gravel into sand, and grinding sand into powder. Some philosophers postulated that the process must stop at some irreducible and tiny level. In short, they believed that everything was made of atoms.
But others recoiled from this idea. If everything is made of small irreducible atoms then what lies between the atoms? The atomist answer was "nothing," but this did not satisfy the anti-atomists who felt that "nature abhors a vacuum." They even constructed elaborate arguments to prove that nothingness could not exist. For them the universe had to be made of continuous matter -- regardless of where you look or how powerful your microscope is, something has to be there.
The discovery of the microscopic world 2,500 years later, and the subsequent development of quantum mechanics to describe atoms, seemed to settle the argument in favor of the atomists. But the story did not end in the 1920s.
Although quantum mechanics successfully described matter it had nothing to say about light. It took another 20 years before this problem was cracked by combining quantum mechanics with Einstein's theory of relativity. The result is called "quantum field theory" and remains our best description of everything to this day.
By the 1960s quantum field theory had grown to encompass all known particles and forces (with the lamentable exception of gravity), but a vexing problem remained -- the theory required that all particles had to be massless, in obvious conflict with experience. A way around the problem was suggested by Peter Higgs, who noted that if one postulated the existence of another particle, and if this particle permeated the entire universe's vacuum, then mass could be accommodated.
Thus we arrive at an astonishing conclusion to a 2,600-year-old debate: The world is made of atoms but nothing also does not exist because Higgs's vacuum is everywhere. As fits a quantum world, both camps were simultaneously right and wrong.
The resulting quantum field theory proved so successful that it was dubbed the Standard Model. Its predictions have passed test after test over the decades. But the cornerstone of the theory, Peter Higgs's particle, remained a fugitive until a few days ago.
Although the final piece of the Standard Model has fallen into place, this is really a beginning because the Higgs is also the gateway to a vast and unknown realm of physics beyond the Standard Model.
Why look for the Higgs particle?
Our society is not just a mechanism designed to enrich some of us. It is something we have created by mutual consent to build things: the rule of law, the concept of inalienable rights, prosperity, great cities, enduring art, and wondrous science. Higgs physics is as beautiful as a Botticelli, as profound as Sartre, as provocative as Warhol and as moving as Garcia Marquez. In the end, it too is a mirror of what it means to be human.
Eric Swanson is a professor of physics at the University of Pittsburgh and a Fellow of the American Physical Society.