American Prometheus (16 page)
He played with his words, inventing complicated puns. There were no broken phrases in Robert’s speech. He had the extraordinary ability to speak in complete, grammatically correct English sentences, without notes, pausing on occasion, as if between paragraphs, to stutter his oddly lilting hum that sounded like “nim-nim-nim.” The relentless patter of his voice was interrupted only by puffs on his cigarette. Every so often, he would twirl toward the blackboard and write out an equation. “We were always expecting him,” recalled one early graduate student, James Brady, “to write on the board with it [the cigarette] and smoke the chalk, but I don’t think he ever did.” As his students filed out of the classroom one day, Robert spotted a Caltech friend, Professor Richard Tolman, sitting in the back. When he asked Tolman what he thought of the lecture, he replied, “Well, Robert, that was beautiful, but I didn’t understand a damn word.”
Robert eventually transformed himself into a skilled and charismatic lecturer, but during his first years at Berkeley he seemed oblivious to the basic principles of communication. “Robert’s blackboard manners were inexcusable,” said Leo Nedelsky, one of his earliest graduate students. Once, when questioned about a particular equation on the blackboard, Oppenheimer replied, “No, not that one; the one underneath.” But when perplexed students pointed out that there was no equation underneath, Robert said, “Not below, underneath. I have written over it.”
Glenn Seaborg, later a chairman of the United States Atomic Energy Commission, complained of Professor Oppenheimer’s “tendency to answer your question even before you had fully stated it.” Frequently he interrupted guest speakers with comments like, “Oh, come now! We all know that. Let’s get on with it.” He refused to suffer fools—or even ordinary physicists—and he never hesitated to impose his own exceedingly high standards on others. In these early years at Berkeley, some thought he “terrorized” his students with sarcasm. “He could . . . be very cruel in his remarks,” recalled one colleague. But as he matured as a teacher, he grew more tolerant of his students. “He was always very kind and considerate to anybody below him,” recalled Harold Cherniss. “But not at all to people who might be considered his intellectual equals. And this, of course, irritated people, made people very angry, and made him enemies.”
Wendell Furry, who studied at Berkeley from 1932 to 1934, complained that Oppenheimer expressed himself “somewhat obscurely and very quickly with flashes of insight which we couldn’t follow.” But even so, Furry recalled, “He praised all of our efforts even when we weren’t so hot.” One day in class, after a particularly difficult lecture, Oppenheimer quipped, “I can make it clearer; I can’t make it simpler.”
As difficult as he was, or perhaps because he was so difficult, most of his students took his courses more than once; indeed, one student, a young Russian woman recalled only as Miss Kacharova, took the course three times, and when she tried to enroll again, Oppenheimer refused to allow it. “She went on a hunger strike,” recalled Robert Serber, “and forced her way in that way.” For those who stuck it out, Oppenheimer found numerous ways to reward their hard work. “One learned from him through conversation and personal contact,” Leo Nedelsky said. “When you took a question to him, he would spend hours—until midnight perhaps—exploring every angle with you.” He invited a good number of his doctoral students to collaborate with him on papers, and he made sure they were listed as coauthors. “It is easy for a famous scientist to have lots of students doing the dirty work for him,” said one colleague. “But Opje helps people with their problems and then gives them the credit.” He encouraged his students to call him “Opje,” the Dutch nickname he had acquired in Leiden. Robert himself began signing his letters with “Opje.” Gradually, his Berkeley students anglicized “Opje” into “Oppie.”
Over time, Oppenheimer developed a uniquely open teaching style in which he encouraged all of his students to interact with each other. Instead of holding office hours and seeing each student individually, he required his eight to ten graduate students and half-dozen postdoctoral fellows to meet together in his office in Room 219, LeConte Hall. Each student had a small desk and chair where he or she sat and watched as Oppenheimer paced the room. Oppie himself had no desk, only a table in the middle of the room piled high with stacks of papers. A blackboard covered with formulae dominated one wall. Shortly before the appointed hour, these young men (and the occasional woman) would straggle in and wait for Oppie as they casually sat on the edge of a table or leaned against the wall. When he arrived, he zeroed in on each student’s particular research problem in turn and solicited comments from everyone. “Oppenheimer was interested in everything,” Serber recalled, “and one subject after another was introduced and coexisted with all the others. In an afternoon, we might discuss electrodynamics, cosmic rays and nuclear physics.” By focusing on the unsolved problems in physics, Oppenheimer gave his students a restless sense of standing on the edge of the unknown.
Very soon it was clear that Oppie had become a “Pied Piper” of theoretical physics. Word spread around the country that if you wished to enter this field, Berkeley was the place to do it. “I didn’t start to make a school,” Oppenheimer later said, “I didn’t start to look for students. I started really as a propagator of the theory which I loved, about which I continued to learn more, and which was not well understood but which was very rich.” In 1934, three of the five students awarded National Research Council fellowships in physics that year chose to study under Oppenheimer. And yet, while they came for Oppenheimer, they came as well for an experimental physicist named Ernest Orlando Lawrence.
Lawrence was everything that Robert Oppenheimer was not. Reared in South Dakota and educated at the universities of South Dakota, Minnesota, Chicago and Yale, Lawrence was a young man supremely confident of his talents. Of Norwegian Lutheran stock, Lawrence had an untroubled all-American demeanor. As a college student, he had paid his tuition peddling aluminum pots and pans to his farmer neighbors. An extrovert, he would use his natural affinity for salesmanship to promote his academic career. Some of his friends thought him a bit of a social climber, but unlike Robert, he possessed not a shred of existential angst or introspection. By the early 1930s, Lawrence was the premier experimental physicist of his generation.
At the time Oppenheimer arrived at Berkeley in the autumn of 1929, Lawrence, twenty-eight years old, was lodging in a room at the Faculty Club. The two very boyish physicists quickly became best friends. They talked almost daily and socialized in the evenings. On weekends they occasionally went horseback-riding. Robert, of course, rode in a Western saddle, but Ernest insisted on distinguishing himself from his farm background by affecting jodhpurs and an English saddle. Robert admired his new friend for his “unbelievable vitality and love of life.” Here was a man, he saw, who could “work all day, run off for tennis, and work half the night.” But he could also see that Ernest’s interests were “primarily active [and] instrumental” while his own were “just the opposite.”
Even after Lawrence married, Oppie was a frequent dinner guest, invariably bringing orchids for Ernest’s wife, Molly. When Molly gave birth to their second son, Ernest insisted on naming the boy Robert. Molly acquiesced, but over the years she grew to think of Oppenheimer as somewhat faux, a man whose elaborate affectations betrayed a certain shallowness of character. Early in her marriage, she did not come between the two friends; but later, when circumstances changed, Molly would push her husband to see Oppie in a different light.
Lawrence was a builder—and he had the fundraising skills to realize his ambitions. In the months before meeting Oppenheimer, he had conceived the notion of building a machine capable of penetrating the so far unassailable nucleus of the atom, which existed, he quipped, “like a fly inside a cathedral.” And not only was the nucleus tiny and elusive, it was also protected by a skin called the Coulomb barrier. Physicists estimated that it would take a stream of hydrogen ions, propelled with the potential of perhaps a million volts, to penetrate it. Generating such levels of high energy seemed an impossibility in 1929; but Lawrence conceived of a way around the impossible. He suggested that a machine could be built that used relatively small 25,000-volt potential to accelerate protons back and forth in an alternating electric field. By means of vacuum tubes and an electromagnet, the ion particles might then be accelerated by the electric field to greater and greater speeds along a spiral path. He was not sure how big an accelerator had to be to penetrate an atom’s nucleus—but he was convinced that with a large enough magnet and a big enough circular chamber, he could break the million-volt mark.
By early 1931, Lawrence had built his first crude accelerator, a machine with a small 4.5-inch chamber within which he generated 80,000-volt protons. A year later, he had an eleven-inch machine that produced million-volt protons. Lawrence now dreamed of building ever bigger accelerators, machines weighing many hundreds of tons and costing tens of thousands of dollars. He coined a new name for his invention, the “cyclotron,” and persuaded the president of the University of California, Robert Gordon Sproul, to give him an old wooden building adjacent to LeConte Hall, the physics building that sat high on the upper end of Berkeley’s beautiful campus. Lawrence named it the Berkeley Radiation Laboratory. Theoretical physicists around the world soon realized that what Lawrence had created in his “Rad Lab” would allow them to explore the innermost reaches of the atom. In 1939, Lawrence won the Nobel Prize for physics.
Lawrence’s relentless drive for ever larger and more powerful cyclotrons epitomized the trend toward the kind of “big science” associated with the rise of corporate America in the early twentieth century. Only four industrial laboratories existed in the country in 1890; forty years later there were nearly one thousand such facilities. In most of these labs a culture of technology, not science, was supreme. Over the years, theoretical physicists like Oppenheimer, devoted to pure “small” science, would find themselves alienated from the culture of these big labs, which were often devoted to “military science.” Even in the 1930s, however, some young physicists couldn’t stand the atmosphere. Robert Wilson, a student of both Oppenheimer and Lawrence, decided to leave Berkeley for Princeton, having concluded that the science associated with these big machines was “an activity that epitomized team research at its worst.”
Building cyclotrons with eighty-ton magnets required large sums of money. But Lawrence was adept at enlisting financial support from such Berkeley regents as oil entrepreneur Edwin Pauley, banker William H. Crocker and John Francis Neylan, a national power broker who happened to be William Randolph Hearst’s chief counsel. In 1932, President Sproul sponsored Lawrence for membership in San Francisco’s elite Bohemian Club, a fraternity of California’s most influential businessmen and politicians. The members of the Bohemian Club would never have thought to welcome Robert Oppenheimer; he was Jewish and too otherworldly. But the Midwestern farm boy Lawrence slipped effortlessly into this elite society. (Later, Neylan got Lawrence into the even more exclusive Pacific Union Club.) Gradually, as Lawrence repeatedly took the money of these powerful men, he found himself also sharing their conservative, anti–New Deal politics.
By contrast, Oppenheimer had a laissez-faire attitude toward the role of money in his own research. When one of his graduate students wrote him for help in raising money for a particular project, Oppie replied whimsically that such research, “like marriage and poetry, should be discouraged and should occur only despite such discouragement.”
On February 14, 1930, Oppenheimer finished writing a seminal paper, “On the Theory of Electrons and Protons.” Drawing on Paul Dirac’s equation on the electron, Oppenheimer argued that there had to be a positively charged counterpart to the electron—and that this mysterious counterpart should have the same mass as the electron itself. It could not, as Dirac had suggested, be a proton. Instead, Oppenheimer predicted the existence of an “anti-electron—the positron.” Ironically, Dirac had failed to pick up on this implication in his own equation, and he willingly gave Oppenheimer the credit for this insight—which soon impelled him, Dirac, to propose that perhaps there existed “a new kind of particle, unknown to experimental physics, having the same mass and opposite charge to an electron.” What he was very tentatively proposing was the existence of antimatter. Dirac suggested naming this elusive particle an “anti-electron.”
Initially, Dirac himself was not at all comfortable with his own hypothesis. Wolfgang Pauli and even Niels Bohr emphatically rejected it. “Pauli thought it was nonsense,” Oppenheimer later said. “Bohr not only thought it was nonsense but was completely incredulous.” It took someone like Oppenheimer to push Dirac into predicting the existence of antimatter. This was Oppenheimer’s penchant for original thinking at its best. In 1932 the experimental physicist Carl Anderson proved the existence of the positron, the positively charged antimatter counterpart to the electron. Anderson’s discovery came fully two years after Oppenheimer’s calculations suggested its theoretical existence. A year later, Dirac won his Nobel Prize.
Physicists around the globe were racing to solve the same set of problems, and the competition to be first was fierce. Oppenheimer proved to be a productive dilettante in this race. Working with a small number of students, he still managed to skip from one critical problem to another just in time to publish a short letter on a particular topic a month or two ahead of the competition. “It was amazing,” recalled one Berkeley colleague, “that Oppenheimer and his group essentially got something on all these problems, about the same time as the competition.” The result might not be elegant or even particularly accurate in all the details—others would have to come along and clean up his work. But Oppenheimer invariably had the essence. “Oppie was extremely good at seeing the physics and doing the calculation on the back of the envelope and getting all the main factors. . . . As far as finishing and doing an elegant job like Dirac would do, that wasn’t Oppie’s style.” He worked “fast and dirty, like the American way of building a machine.”
