Джеймс Глик - Genius - The Life and Science of Richard Feynman

He rose from his desk and walked out the door and down the corridor, drumming his knuckles along the wal . The writer heard him shout, just before he disappeared: “It’s goddamned useless to talk about these things! It’s a complete waste of time! The history of these things is nonsense! You’re trying to make something difficult and complicated out of something that’s simple and beautiful.”

Across the hal Murray Gel -Mann looked out of his office.

“I see you’ve met Dick,” he said.

Feynman had always set high standards for fundamental work, although he meant something broader by the word than many particle physicists did. Liquid helium and other

than many particle physicists did. Liquid helium and other solid-state problems had seemed to him as fundamental as the smal est-scale particle interactions. He believed that fundamentalness, like beauty or intel igence, was a multidimensional quality. He had tried to understand turbulence and quantum gravity. Throughout his career he had suffered painful periods of malaise, when he could not find a suitable problem. In later years he and his col eagues had seen their crowded field thin: bright young students, looking for fundamental issues on their own terms, often turned to biology, computation, or the new study of chaos and complexity. When his son, Carl, ended his flirtation with philosophy and took up computer science, Feynman, too, looked again at the field he had helped pioneer at Los Alamos. He joined two Caltech authorities on computation, John Hopfield and Carver Mead, in constructing a course on issues from brain analogues and pattern recognition to error correction and uncomputability. For several summers he worked with the founders of Thinking Machines Corporation, near MIT, creating a radical approach to paral el processing; he served as a high-class technician, applying differential equations to the circuit diagrams, and as an occasional wise man among the young entrepreneurs (“Forget al that ‘local minima’ stuff—just say there’s a bubble caught in the crystal and you have to shake it out”). And he began to produce maverick research at the intersection of computing and physics: on how smal computers could be; on entropy and the uncertainty principle in computing; on simulating quantum physics and probabilistic behavior; and on the possibility of building a

probabilistic behavior; and on the possibility of building a quantum-mechanical computer, with packets of spin waves roaming bal istical y back and forth through the logic gates.

His own community had largely left behind questions with the spirit that first drove him toward physics. An intel ectual distance had opened between the subatomic particle universe and the realm of ordinary phenomena—the magic that nature reveals to children. In The Feynman Lectures he spoke al egorical y of the beauty of a rainbow. Imagine a world in which scientists could not see a rainbow: they might discover it, but could they sense its beauty? The essence of a thing does not always lie in the microscopic details. He supposed that the blind scientists learned that, in some weathers, the intensity of radiation plotted against wavelength at a certain direction in the sky would show a bump, and the bump would shift from one wavelength to another as the angle of the instrument shifted. “Then one day,” he said, “the physical review of the blind men might publish a technical article with the title ‘The Intensity of Radiation as a Function of Angle under Certain Conditions of the Weather.’” Feynman had no quarrel with beauty —our human il usion, our projection of sentiment onto a reality of radiation phenomena.

“We are al reductionists today,” said Steven Weinberg—

meaning that we seek the deepest explanatory principles in the elementary particles that underlie ordinary matter. He spoke for many particle physicists but not for Feynman.

Understanding the principles at the lowest level of the hierarchy—the smal est length-scales—is not the same as

understanding nature. So much lies outside the accelerators’ domain, even if it is in some sense reducible to elementary particles. Chaotic turbulence; the large-scale structures that emerge in complex systems; life itself: Feynman spoke of “the infinite variety and novelty of phenomena that can be generated from such simple principles”—phenomena that are “in the equations; we just haven’t found the way to get them out.”

The test of science is its ability to predict. Had you never visited the earth, could you predict the thunderstorms, the volcanoes, the ocean waves, the auroras, and the colorful sunset? …

The next great era of awakening of human intel ect may wel produce a method of understanding the qualitative content of equations. Today we cannot.

Today we cannot see that the water-flow equations contain such things as the barber pole structure of turbulence that one sees between rotating cylinders.

Today we cannot see whether Schrödinger’s equation contains frogs, musical composers, or morality—or whether it does not.

Physicists’ models are like maps: never final, never complete until they grow as large and complex as the reality they represent. Einstein compared physics to the conception a person might assemble of the interior mechanism of a closed watch: he might build a plausible model to account for the rhythmic ticking, the sweep of the

hands, but he could never be certain. “He may also believe in the existence of the ideal limit of knowledge and that it is approached by the human mind,” Einstein said. “He may cal this ideal limit the objective truth.” It was a simpler time.

In Feynman’s era, knowledge advanced, but the ideal of objective truth receded deeper into the haze beyond the vision of science. Quantum theory had left an impossible question dangling in the air. One physicist chose to answer it by quoting Feynman, “one of the great philosophers of our time, whose view of the matter I have taken the liberty of quoting in the form of the poetry it surely is”: We have always had a great deal of difficulty understanding the world view

that quantum mechanics represents.

At least I do,

because I’m an old enough man

that I haven’t got to the point

that this stuff is obvious to me.

Okay, I stil get nervous with it….

You know how it always is,

every new idea,

it takes a generation or two

until it becomes obvious

that there’s no real problem….

I cannot define the real problem,

therefore I suspect there’s no real problem, but I’m not sure

there’s no real problem.

In October 1987 another abdominal tumor appeared, and his doctors made one last attempt to stal his cancer surgical y. When the Los Angeles Times sent him an advance copy of his obituary, he thanked the author but said, “I have decided it is not a very good idea for a man to read it ahead of time: it takes the element of surprise out of it.” He knew he was not recovering. He was sixty-nine years old. Pain wracked one of his legs. He was exhausted. He had no appetite. In January he began awakening in the night with sweats and chil s. In one corner of his dusty office blackboard he had written a pair of self-conscious mottoes:

“What I cannot create I do not understand” and “Know how to solve every problem that has been solved.” Nearby was a running list under the heading, “TO LEARN” (“Bethe Ansatz Prob., 2D Hal …”). Physics changed; he talked about it once with his old Los Alamos friend Stanislaw Ulam, who had been watching a few white clouds rol against the blue New Mexico sky. Feynman seemed to read his mind: “It is real y like the shape of clouds,” he said.

“As one watches them they don’t seem to change, but if you look back a minute later, it is al very different.” He had not accumulated much: a hand-knitted scarf, hanging on a peg,