Genius (51 page)

The prestige of particle physics also rose with a flood tide of military support. Most plainly, the weapons laboratories prospered and such agencies as the Office of Naval Research financed specific military research projects.

A host of applied sciences, from electronics to cryptography, benefited from the concrete interest of military program officers. Academic scientists could immediately see the potential danger of allowing the armed forces to direct the course of scientific research. “When science is allowed to exist merely from the crumbs that fall from the table of a weapons development program,” said Caltech’s new president, Lee DuBridge, “then science is headed into the stifling atmosphere of ‘mobilized secrecy’ and it is surely doomed—even though the crumbs themselves should provide more than adequate nourishment.” Yet the military also recognized this. One of the many legacies of the Manhattan Project was that generals and admirals now believed the scientists’ dogma: that researchers left alone to follow their instincts will lay golden eggs. The bomb had been born of the esoteric fancies of the mandarins—that was clear. Now
pure
physicists wished to conduct basic research into forces and particles even stranger than those powering atomic bombs; the public and the government supported them enthusiastically. At institutions like DuBridge’s Caltech, even the theoretical programs of research on particle physics flourished by accepting enormous government grants to which the professors applied in groups. The grants paid for salaries, graduate students, office expenses, and university overhead. The military actively encouraged, when it did not finance directly, the giant cyclotrons, betatrons, synchrotrons, and synchrocyclotrons, any one of which consumed more steel and electricity than a prewar experimentalist could have imagined. These were not so much crumbs from the weapons-development table as they were blank checks from officials persuaded that physics worked miracles. Who could say what was impossible? Free energy? Time travel? Antigravity? In 1954 the secretary of the army invited Feynman to serve as a paid consultant on an army scientific advisory panel, and he agreed, traveling to Washington for several days in November. At a cocktail party after one session, a general confided that what the army really needed was a tank that could use sand as fuel.

Earlier that year Feynman had picked up the telephone in Pasadena to hear the chairman of the AEC, Admiral Lewis L. Strauss, say that he had won his first major prize, the Albert Einstein Award: fifteen thousand dollars and a gold medal. He was the third winner, after Kurt Gödel and Julian Schwinger. Strauss informed him of the award (Feynman amused him by saying, “Hot dog!”). The public announcement came from Oppenheimer as director of the Institute for Advanced Study. Only gradually did it occur to Feynman that this was the same Strauss who was in the process of permanently removing Oppenheimer from public life. Strauss had carried out President Dwight D. Eisenhower’s order to strip Oppenheimer of his security clearance, after a letter to J. Edgar Hoover accused him, in the fashion of the time, of being a “hardened Communist” who was probably “functioning as an espionage agent.” The AEC began four weeks of hearings in April. Many physicists publicly defended the man they had so admired over the past decade. The famous, damaging exception was Teller, who complained that Oppenheimer had not supported his hydrogen bomb project and testified, choosing his words carefully, “I feel that I would like to see the vital interests of this country in hands which I understand better, and therefore trust more.” Under the circumstances Feynman did not relish the prospect of accepting the award from Strauss. But Rabi, who was visiting Caltech, advised him to go ahead. “You should never turn a man’s generosity as a sword against him,” he recalled Rabi saying. “Any virtue that a man has, even if he has many vices, should not be used as a tool against him.”

In the frightened climate, atomic scientists developed an invisible trail of agents, questioning their friends and childhood neighbors, painstakingly uncovering the obvious, trying to tune in to a hearsay of who liked whom, who resented whom, who might be likely to inform on whom. Feynman’s own file at the FBI grew bulky. His Los Alamos friend Klaus Fuchs had been imprisoned in 1950 for spying for the Soviet Union. Fortunately for Feynman, the bureau did not realize how often Fuchs had lent Feynman his car. It was noted that Feynman had once made a speech at Temple Israel in Far Rockaway, “at which time he had spoken on brotherhood.” He was described as a shy, retiring, introverted type of individual. Neighbors vouched for his loyalty and doubted that he had participated in the high school’s Young People’s Socialist League, which an investigating agent described as “a militant, pro-communistic group of students.” Bethe was pestered by an officer of the Department of Commerce for information regarding Feynman’s “loyalty.” Finally he replied curtly, “Professor Feynman is one of the leading theoretical physicists of the world. His loyalty to the United States is unquestioned. Any further elaboration would be an insult to Dr. Feynman.”

On one occasion the bureau discovered a “contact by Oppenheimer with one ‘F
INEMAN
’ (phonetic)” and surmised “that this ‘F
INEMAN
’ is in fact subject R
ICHARD
F
EYNMAN
.” Officials discussed the possibility of turning him into a confidential informant against Oppenheimer. They authorized a discreet approach and then placed Feynman on the “no contact” list when he refused to be interviewed by the bureau about anything at all. Agents interviewed his Los Alamos colleagues, who generally described him as a “prodigy” of “excellent character.” Yet it was learned that he sometimes boasted of having “out-foxed” the Selective Service psychiatrists to obtain a 4-F classification. One colleague considered him a “screwball.” Another felt that his interest in “jazz” was not in keeping with the usual demeanor of a physics professor. Yet he had voted for Eisenhower, according to informants, registered Independent (not to be confused with Independent Progressive), and “had no respect whatsoever for the Russians.” The bureau carefully copied out newspaper accounts of his divorce. And one oddity had to be reported:

F
EYNMAN
has developed a fair degree of skill opening sample tumbler and Yale type locks with hairpins, bits of wire, etc… . Feynman has been trying to learn the workings of safe locks and has expressed an ambition to be able to open a safe.

In this first report the agent tried diligently to understand the exculpatory opinion of the informant that “this was not indicative of any criminal tendencies on the part of Feynman but was merely one of the works of a brilliant mathematical mind challenged by a device considered practically impossible of solution by an ordinary individual.” Nevertheless, the suggestive combination of
opened safes containing atomic secrets
and
socialized with Klaus Fuchs
proved irresistible to the anonymous authors of memorandums, special inquiries, and secret airtels that swelled Feynman’s file for years to come.

The bureau monitored one other incident with particular interest. The Soviet Academy of Sciences invited Feynman to a conference in Moscow, where he would have had a chance to meet the great Lev Landau and other Russian physicists. Nuclear physics, particularly in its sensitive guises, was not on the agenda. Still, the cream of Soviet physics was engaged in a weapons program quickly catching up with the Americans’. That year the Russians exploded an advanced, portable thermonuclear bomb over Siberia. (One of its principal architects, the future dissident Andrei Sakharov, watched from a platform on the snowy steppe, miles from ground zero. Having read an American primer called the black book, he decided it would be safe to remove his dark goggles.) Feynman accepted the invitation enthusiastically, the Soviet Academy having offered to cover his travel expenses. Then he had second thoughts. He wrote a careful letter to the AEC to ask for the government’s advice. “I thought you would be interested,” he said, “because I was connected to the Los Alamos project during the war, so the danger that I might not be able to return, or the attitude of public opinion must be considered.” After a delay, officials at both the commission and the State Department replied, asking him to turn the Soviets down. His presence might be exploited for “propaganda gains.” Feynman acquiesced. He wrote the head of the Soviet Academy that “circumstances have arisen which make it impossible for me to attend.” The government also forced Freeman Dyson to withdraw, warning him that under the McCarran Immigration Act he might not be allowed back into the United States. Dyson did not surrender so quietly, however. He told newspaper reporters, “This is a clear case in which the law has been proved stupid.”

In their basic, nonweapons research, Russian physicists eagerly pursued the latest developments in the United States and Europe. Yet a faint difference in outlook between East and West was already unfolding. The triumph of the atomic bomb had been an American triumph, had won the American war, and had not ingrained itself so firmly into the Soviet psyche (obsessed though policymakers were with the arms race). Although an international-class synchrocyclotron went up in Dubno, money was not so readily available for giant particle accelerators of the kind now under construction in the United States. And the most influential single figure in Soviet physics was Landau, famous for the catholicity of his interests across the whole breadth of phenomena that could be called theoretical physics. He had devoted his greatest work not to elementary particles but to condensed matter: the dynamics of fluids, transitions between one phase of matter and another, turbulence, plasmas, sound dispersion, and low-temperature physics. Fundamental though all these subjects were, in the United States their status was beginning to dim slightly next to the glamour of particle physics. Not so in the Soviet Union, where physicists were particularly eager in 1955 to meet Feynman. For his first major work since quantum electrodynamics, he had turned away from particle physics after all and chosen instead a subject close to Landau’s heart: a theory of superfluidity, the frictionless motion of liquid helium cooled to near absolute zero.

A Quantum Liquid

By then science-fiction writers had learned an interesting rule: not to let their imaginations run too freely, too widely. It was often better to be conservative. To create a strange new world, they had only to alter one or two features of the usual reality and let the manifold unexpected implications play themselves out. Nature, too, seemed capable of adjusting a single rule and thereby creating the most bizarre phenomena.

Superfluid helium showed what happens when a liquid can flow with no friction—not just low friction, but zero friction. Resting in a beaker, the liquid spontaneously glides in a thin film up and over the walls, apparently in defiance of gravity. It passes through cracks or holes so microscopically small that even a gas would not fit through. No matter how perfectly a pair of glass plates are polished to a smooth surface, and no matter how hard they are pressed together, superfluid helium will still flow freely between them. The liquid conducts heat far better than any ordinary substance, and no amount of cooling will freeze it into a solid.

When Feynman talked about fluid flow, he knew he was returning to a childlike, elemental fascination with the world as it is. The pleasure of watching water in bathtubs or mud puddles on the sidewalk, of trying to dam a curbside rivulet after a rainstorm, of contemplating the movement in waterfalls and whirlpools—that was what made every child a physicist, he felt. In trying to understand superfluidity, he began once again with first principles. What was a fluid? A substance, liquid or gas, that cannot withstand a shear stress, but moves under the force. The tendency of a fluid to resist the shear is its viscosity, its internal friction—honey being more viscous than water, water more than air. Nineteenth-century physicists creating the first effective equations for fluid flow found viscosity especially troublesome, so uncomputable were its consequences. For the sake of simplicity, they often created models that ignored viscosity—and for that John von Neumann later mocked them. Modelers always tried to omit unnecessary complication—that was one thing. But classical fluid dynamicists had omitted what seemed an essential, defining quality. Sarcastically von Neumann called them theorists of “dry water.” Superfluid helium, Feynman said, resembled that impossible idealization, fluid without viscosity. It was dry water.

Superfluidity had an equally bizarre twin, superconductivity, the flow of electricity with no dissipation or resistance. Both were phenomena of low-temperature experimentation. Superconductivity had been discovered in 1911; superfluidity not until 1938, because of the difficulties of watching the behavior of a liquid inside a pinhead-size container in a supercooled cryostat. Esoteric though they were, by the fifties this pair of phenomena had become crown jewels of the side of theoretical physics not devoted to elementary particles. Little progress had been made in understanding the perpetual-motion machinery that seemed to be at work. It seemed to Feynman that they were like “two cities under siege … completely surrounded by knowledge although they themselves remained isolated and unassailable.” Besides Landau, the chief contributor to the theorizing on superfluidity was Lars Onsager, the distinguished Yale chemist whose notoriously difficult courses in statistical mechanics were sometimes called (in allusion to Onsager’s accent) Norwegian I and Norwegian II.

Nature had exhibited another kind of perpetual motion, familiar to quantum physicists: motion at the level of electrons in the atom. No friction or dissipation slowed electrons. Only in the interactions of crowds of atoms did the energy drain of friction arise. Were these super phenomena somehow escaping the incoherent tumult of classical matter? Was this a case of quantum mechanics writ large? Could the whole apparatus of wave functions, energy levels, and quantum states translate itself onto macroscopic scales? The most basic clue that this was indeed large-scale quantum behavior came from the apparent unwillingness of helium to freeze into hard crystals at any temperature. Classically, absolute zero was often described as the temperature at which all motion ceases. Quantum mechanically, there is no such temperature. Atomic motion never does cease. That precise a zero would violate the uncertainty principle.