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

Mathematics is always where they begin, for no other school course shows off their gifts so clearly. Yet a crisis comes: they experience an epiphany, or endure a slowly building disgruntlement, and plunge or drift into this other, hybrid field. Werner Heisenberg, seventeen years older than Feynman, experienced his moment of crisis at the University of Munich, in the office of the local statesman of mathematics, Ferdinand von Lindemann. For some reason Heisenberg could never forget Lindemann’s horrid yapping

black dog. It reminded him of the poodle in Faust and made it impossible for him to think clearly when the professor, learning that Heisenberg was reading Weyl’s new book about relativity theory, told him, “In that case you are completely lost to mathematics.” Feynman himself, halfway through his freshman year, reading Eddington’s book about relativity theory, confronted his own department chairman with the classic question about mathematics: What is it good for? He got the classic answer: If you have to ask, you are in the wrong field. Mathematics seemed suited only for teaching mathematics. His department chairman suggested calculating actuarial probabilities for insurance companies. This was not a joke. The vocational landscape had just been surveyed by one Edward J. v. K.

Menge, Ph.D., Sc.D., who published his findings in a monograph

titled Jobs for the College Graduate in Science . “The American mind is taken up largely with applications rather than with fundamental principles,”

Menge noticed. “It is what is known as ‘practical.’” This left little

room

for

would-be

mathematicians:

“The

mathematician has little opportunity of employment except in the universities in some professorial capacity. He may become a practitioner of his profession, it is true, if he acts as an actuary for some large insurance company… .”

Feynman changed to electrical engineering. Then he changed again, to physics.

Not that physics promised much more as a vocation. The membership of the American Physical Society stil fel shy of two thousand, though it had doubled in a decade.

of two thousand, though it had doubled in a decade.

Teaching at a col ege or working for the government in, most likely, the Bureau of Standards or the Weather Bureau, a physicist might expect to earn a good wage of from three thousand to six thousand dol ars a year. But the Depression had forced the government and the leading corporate laboratories to lay off nearly half of their staff scientists. A Harvard physics professor, Edwin C. Kemble, reported that finding jobs for graduating physicists had become a “nightmare.” Not many arguments could be made for physics as a vocation.

Menge, putting his pragmatism aside for a moment, offered perhaps the only one: Does the student, he asked,

“feel the craving of adding to the sum total of human knowledge? Or does he want to see his work go on and on and his influence spread like the ripples on a placid lake into which a stone has been cast? In other words, is he so fascinated with simply knowing the subject that he cannot rest until he learns al he can about it?”

Of the leading men in American physics MIT had three of the best, John C. Slater, Philip M. Morse, and Julius A.

Stratton. They came from a more standard mold—

gentlemanly, homebred, Christian—than some of the physicists who would soon eclipse them, foreigners like Hans Bethe and Eugene Wigner, who had just arrived at Cornel University and Princeton University, respectively, and Jews like I. I. Rabi and J. Robert Oppenheimer, who had been hired at Columbia University and the University of California at Berkeley, despite anti-Semitic misgivings at

both places. Stratton later became president of MIT, and Morse became the first director of the Brookhaven National Laboratory for Nuclear Research. The department head was Slater. He had been one of the young Americans studying overseas, though he was not as deeply immersed in the flood tides of European physics as, for example, Rabi, who made the ful circuit: Zurich, Munich, Copenhagen, Hamburg, Leipzig, and Zurich again. Slater had studied briefly at Cambridge University in 1923, and somehow he missed the chance to meet Dirac, though they attended at least one course together.

Slater and Dirac crossed paths intel ectual y again and again during the decade that fol owed. Slater kept making minor discoveries that Dirac had made a few months earlier. He found this disturbing. It seemed to Slater furthermore that Dirac enshrouded his discoveries in an unnecessary and somewhat baffling web of mathematical formalism. Slater tended to mistrust them. In fact he mistrusted the whole imponderable miasma of philosophy now flowing from the European schools of quantum mechanics: assertions about the duality or complementarity or “Jekyl -Hyde” nature of things; doubts about time and chance; the speculation about the interfering role of the human observer. “I do not like mystiques; I like to be definite,” Slater said. Most of the European physicists were reveling in such issues. Some felt an obligation to face the consequences of their equations. They recoiled from the possibility of simply putting their formidable new technology to work without developing a physical picture to go along

with it. As they manipulated their matrices or shuffled their differential equations, questions kept creeping in. Where is that particle when no one is looking? At the ancient stone-built universities philosophy remained the coin of the realm.

A theory about the spontaneous, whimsical birth of photons in the energy decay of excited atoms—an effect without a cause—gave scientists a sledgehammer to wield in late-evening debates about Kantian causality. Not so in America. “A theoretical physicist in these days asks just one thing of his theories,” Slater said defiantly soon after Feynman arrived at MIT. The theories must make reasonably good predictions about experiments. That is al .

He does not ordinarily argue about philosophical implications… . Questions about a theory which do not affect its ability to predict experimental results correctly seem to me quibbles about words, … and I am quite content to leave such questions to those who derive some satisfaction from them.

When Slater spoke for common sense, for practicality, for a theory that would be experiment’s handmaid, he spoke for most of his American col eagues. The spirit of Edison, not Einstein, stil governed their image of the scientist. Perspiration, not inspiration. Mathematics was unfathomable and unreliable. Another physicist, Edward Condon, said everyone knew what mathematical physicists did: “they study careful y the results obtained by experimentalists and rewrite that work in papers which are

so mathematical that they find them hard to read themselves.” Physics could real y only justify itself, he said, when its theories offered people a means of predicting the outcome of experiments—and at that, only if the predicting took less time than actual y carrying out the experiments.

Unlike their European counterparts, American theorists did not have their own academic departments. They shared quarters with the experimenters, heard their problems, and tried to answer their questions pragmatical y. Stil , the days of Edisonian science were over and Slater knew it. With a mandate from MIT’s president, Karl Compton, he was assembling a physics department meant to bring the school into the forefront of American science and meanwhile to help American science toward a less humble world standing. He and his col eagues knew how unprepared the United States had been to train physicists in his own generation. Leaders of the nation’s rapidly growing technical industries knew it, too. When Slater arrived, the MIT department sustained barely a dozen graduate students. Six years later, the number had increased to sixty. Despite the Depression the institute had completed a new physics and chemistry laboratory with money from the industrialist George Eastman. Major research programs had begun in the laboratory fields devoted to using electromagnetic radiation as a probe into the structure of matter: especial y spectroscopy, analyzing the signature frequencies of light shining from different substances, but also X-ray crystal ography. (Each time physicists found a new kind of “ray” or particle, they put it to