Synopsis
Book by Johnson George
Extrait
It was Memorial Day weekend of 1996, in the middle of what turned out to be one of New Mexico's worst droughts of the century. The seemingly endless dry spell reminded many of the climatic disaster said to have driven the Anasazi, the original inhabitants of this land, from their stone settlements around Mesa Verde, causing the collapse of a civilization. To escape the heat, I left my house in Santa Fe and drove as high as you can go into the nearby Sangre de Cristo Mountains. After leaving my Jeep in the ski basin parking lot, already some 10,000 feet above sea level, I began walking higher. My destination, La Vega, "the meadow," lay at the base of Santa Fe Baldy, an 11,600-foot peak of Precambrian granite that juts above the timberline.
Almost as soon as I reached the trail head, I realized that, once again, I had misjudged the perversity of New Mexico weather. Looking out across the Rio Grande Valley, I could see the next mountain range, the Jemez, where just weeks earlier a fire had devastated fifteen thousand acres of one of my favorite places, the wilderness backcountry of Bandelier National Monument. Now storm clouds were boiling up over the Jemez and sweeping toward the Sangre de Cristos. The temperature began dropping, and before long snow flurries, of all things, were swirling around me.
I was wishing I had worn a jacket and long pants instead of khaki shorts and a T-shirt, when, as I rounded a corner on the trail, I heard a familiar voice. "Well, hello," a man in a floppy cotton hat and a windbreaker called out enthusiastically. He was walking toward me from the opposite direction. "How are you?" he said. It took me a few seconds to realize that I had randomly encountered the subject of this biography, my Santa Fe neighbor Murray Gell-Mann, hiking with his stepson, Nick Levis.
For weeks now I had been trying to pin down Gell-Mann for another interview. He had been running hot and cold ever since I had told him, two years earlier, that I intended to write his life story. Lately he had been more helpful. But now I was worrying that his second thoughts were being followed by third and fourth thoughts, and I had no idea what stage our relationship was in. I was relieved that he seemed genuinely pleased to see me. And I was struck again by how much, contrary to so many of the legends, Gell-Mann liked people and conversation, the easy camaraderie of encountering someone familiar on a mountain trail. The physics lore is filled with stories of Gell-Mann cutting down a colleague with a withering remark, of the mocking names he assigned to people whose ideas he didn't respect. Particle physics is the most competitive of intellectual sports, and faced with a theory or a theorist he didn't like, Gell-Mann could be merciless. But up in the mountains, in New Mexico, he seemed almost able to relax.
He introduced me to Nick, who like me was shivering without a jacket. When I said I was headed for La Vega, Gell-Mann was delighted at the coincidence. "La Vega," he said, his mouth stretched wide to mimic as perfect a northern New Mexican accent as you might hear in the villages of Chimayo or Truchas, down the other side of the mountain. He and Nick had also been heading to La Vega when the drop in temperature caused them to turn around, a little way up the trail, at Nambe Creek -- "NAM-be," Murray said, with just the right amount of padding around the b. Now they were heading home.
If Gell-Mann was disappointed about not reaching this particular goal, he didn't show it. His eyes sparkled, and he seemed happy just to be out in the woods again. A few weeks earlier, the cardiologists had stuck a catheter in his chest, checking on his progress since a recent heart attack. They were relieved to find that the artery they had scraped out -- a Roto-rooting, Gell-Mann called it -- was still open. There was another, less threatening obstruction further downstream, but the doctors decided to leave it alone.
I was tempted to turn around and join Murray and Nick on the hike back. But somehow it seemed improper. This was not Murray Gell-Mann, the Nobel laureate, the discoverer of the quark and the Eightfold Way, but simply a man on a holiday with his stepson. My strategy all along had been to avoid making him feel cramped. I was in this for the long haul. After a few minutes, we parted ways. I made it about a mile past Nambe Creek. Then, just before the descent into the meadow, the clouds went black and I also decided to save La Vega for another day. Heading back down the mountain, I thought about how much I had come to like this brilliant, complicated, always fascinating, and often exasperating man.
When we visit the ruins of ancient civilizations, we reserve a peculiar fascination for those giant, elaborate structures that seem to serve no practical purpose whatsoever: the pyramids built by the Egyptians on the Nile and the Maya in Mexico, or the large circular kivas of Chaco Canyon in northwestern New Mexico. They stand meaningless now, rock-solid projections long outlasting whatever ideas they were meant to represent. Catholicism still survives, so we can understand some of the rationale behind Chartres, St. Peter's, and the other great cathedrals and basilicas of Europe. But we have barely a hint of the ideas that motivated the construction of the Sphinx.
It is sometimes said that the cathedrals of the late twentieth century are the giant particle accelerators, monuments to the belief -- far from obvious on its face -- that buried beneath the rough surface of the world we inhabit is a crystalline order so beautiful and subtle the mind can barely grasp it. Engaging in a fantasy, we can imagine, centuries and centuries from now, archaeologists (from this planet or perhaps from beyond the solar system) perplexed and captivated by the remains of the seventeen-mile-circumference particle accelerator being constructed at CERN, the European Center for Nuclear Research, near Geneva, or the four-mile ring at Fermilab in Illinois. These "atom smashers" are among the largest, most powerful machines ever built by the human race -- not for the purpose of generating power, like the dams and nuclear reactors, or for predicting the weather or simulating nuclear explosions, like the supercomputers. Their sole purpose is intellectual: to find the faintest glimmers of evidence that, despite so many appearances to the contrary, we live in a mathematically symmetrical universe. How is it that a civilization long ago became so obsessed with this idea? That will be the riddle of these twentieth-century sphinxes.
If our parchments and our data banks survive along with the wreckage of our great machines, the archaeologists will learn a remarkable story: How the elders of the church of science came to believe that, despite what we perceive, matter is not continuous; it is made of invisible particles linked together in a beautiful architecture. As the atomists would show over the years, the seemingly infinite variety of the world is generated by some one hundred elements, neatly arranged in the Russian chemist Dmitri Mendeleev's periodic table of the elements.
Viewed from the heavens, any hint of geometry on the earth -- land divided into rectangles and circles, rock cut into blocks and piled straight and high -- is usually a sign of intelligent creatures imposing order on an irregular world. But surely, the scientists believed, this harmony we find so soothing runs deeper. Beneath the world's confusion of forms is a scaffolding built according to a geometry as pleasing to the mind as a Gothic cathedral.
Since no one could directly see this geometry, the best one could hope for was to study its shadows. And so the physicists began to build the machinery they believed would provide an indirect glimpse. At first these devices were as simple as a jar enclosing gold foil leaves that seemed to waft in the wind of an invisible essence called electricity. By the early twentieth century, scientists were making gas-filled tubes that glowed in the dark with what they took to be mysterious beams of positive and negative charge. By studying and measuring these weird emanations, the physicists reached a powerful consensus: The world was even more elegant and symmetrical than Mendeleev and the atomists dared imagine. The variety of atoms found on the earth and in the sky were made up of combinations of just three particles: the proton, the electron, and the neutron.
But this newfound simplicity was short-lived. Not content with their instruments, the scientists built bigger and bigger machines. With the first particle accelerators, small enough to fit on a tabletop, they began smashing their elementary particles into each other and discovered that they weren't so elementary after all. They could be shattered into fragments. When they built bigger accelerators to smash the pieces even harder, they were left with fragments of fragments. Placing carefully designed detectors on mountaintops or sending them aloft in balloons, they found traces of still other particles, the cosmic rays bombarding the planet from space. Soon, there were so many of these "elementary" constituents that they threatened the very desire for order that had driven the search. The physicists were in despair.
And then, leading them out of the confusion, came the young scientists whose string of discoveries would do so much to make sense of it all, to find pattern hiding beneath the confusion. Viewed through these magicians' wonderful new lenses, the clouds lifted and order shone through. But it came at a curious price. To restore beauty to the core of creation, humanity was asked to believe in truths stranger than any that had come before.
The most remarkable of these wizards was Murray Gell-Mann. Graduating from Yale University at age eighteen, by the time he was twenty-one he had earned a Ph.D. from the Massachusetts Institute of Technology. Less than three years later, he began his revolution with an astonishing theory explaining the unlikely behavior of certain cosmic rays -- the so-called "strange particles" that bombarded the earth from space. The legend was born. From then until a decade later, when he proposed the existence of quarks, Gell-Mann dominated particle physics. He is sometimes called the Mendeleev of the twentieth century, for what he provided was no less than a periodic table of the subatomic particles. In a fanciful allusion to Buddhist philosophy, Gell-Mann called his organizing scheme the Eightfold Way. While the periodic table shows that the plenitude of atoms can be generated by combining just three particles -- the proton, electron, and neutron -- the Eightfold Way shows that the hundreds of subatomic particles are made up of a handful of the elements Gell-Mann named quarks. Complexity was reduced to simplicity again.
But there is an important difference between the architecture of Mendeleev and the architecture of the Eightfold Way. And it is here that one can glimpse the enormity of the intellectual upheaval brought on by Gell-Mann and his colleagues. The periodic table, now a commonplace in any high school chemistry course, classifies the elements according to properties we can perceive with our senses. Every element is characterized by a unique mass and charge. Mass is something we feel when we pick up a rock; we generate charge when we shuffle across a carpet and touch a doorknob.
Classified according to these commonsense qualities, the elements miraculously arrange themselves into columns -- the rare earth metals, the noble gases, and so forth -- whose members share similar characteristics.
In its ability to sift pattern from chaos, the Eightfold Way is at least as powerful, but tantalizingly more subtle. The qualities Gell-Mann used to arrange the subatomic particles were far more abstract than charge and mass. In his scheme, particles were classified according to elusive qualities called isospin and strangeness, which have no counterpart in the world of everyday experience. To describe the invisible patterns said to underlie the material world, Gell-Mann's strangeness was soon followed by more new qualities with names like charm, truth, and beauty. They "exist" not within the familiar world of three dimensions (four, if you include time), but within artificially constructed mathematical spaces, imaginary realms of pure abstraction.
Was this world stuff or mind stuff? To say that Gell-Mann "discovered" the quark is not quite right. All of his great breakthroughs came from playing with symbols on paper and chalkboards. His most important tools, he liked to say, were pencil, paper, and wastebasket. His discoveries were not of things but of patterns -- mathematical symmetries that seemed to reflect, in some ultimately mysterious way, the manner in which subatomic particles behaved. But then "invented the quark" is not quite right either -- implying some kind of postmodern relativism in which science is pure construction, just another philosophy. When Mendeleev drew his table, he left blank spaces for unknown elements that were discovered only years later. This manmade artifice was predicting truths about the real world. And so it was with the Eightfold Way. New kinds of particles demanded by Gell-Mann's abstract invention showed up in the experimenters' atom smashers.
The conflicting views of the nature of scientific ideas -- are they discovered or invented? -- are starkly laid out in the titles of two books: The Hunting of the Quark by Michael Riordan and Constructing Quarks by Andrew Pickering. Are quarks real particles (whatever that means) or mathematical contrivances? It's a debate that Gell-Mann refused to engage in. Philosophy, he thought, was a waste of time. But the puzzling questions about the reality of quarks -- particles that cannot in principle be independently observed -- quietly churned in his mind. One can see the struggle in the words he wrote and the lectures he gave. Ultimately he and just about everyone stopped worrying about it. Whether invented or discovered or something in between, it was Gell-Mann's quarks and his Eightfold Way that laid the foundation for the explanation physicists have given for how the world is made. For years particle physicists argued over who was the smartest person in their field: Richard Feynman or Murray Gell-Mann.
This idea of breaking the world into pieces and then explaining the pieces in terms of smaller pieces is called reductionism. It would be perfectly justified to consider Gell-Mann, the father of the quark, to be the century's arch-reductionist. But very early on, long before mushy notions of holism became trendy, Gell-Mann appreciated an important truth: While you can reduce downward, that doesn't automatically mean you can explain upward. People can be divided into cells, cells into molecules, molecules into atoms, atoms into electrons and nuclei, nuclei into subatomic particles, and those into still tinier things called quarks. But, true as that may be, there is nothing written in the laws of subatomic physics that can be used to explain higher-level phenomena like human behavior. There is no way that one can start with quarks and predict that cellular life would emerge and evolve over the eons to produce physicists. Reducing downward is vastly easier than explaining upward -- a truth that bears repeating.
In the last decade, what aspires to be a new branch of science has sprung up to try and come to grips with complex phenomena -- organisms, economies, ecosystems, societies, the thunderstorms that sweep through the Rockies. Gell-Mann, some fifteen years after winning a Nobel Prize for his reductionist tour de force, reversed direction and helped found the Santa Fe Institute, a world center for studying complexi...
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