Big Science

by Michael Hiltzik

  • • •

  In the mid-1920s, the University of California was at a crossroads. It had plenty of money and superb facilities, yet it was struggling to build a reputation for scholarship commensurate with its riches. The money flowed from private donors and from government grants, the latter partially the result of contributions by Berkeley chemists and engineers to the American war effort. The country’s success in the Great War inspired a new appreciation across the land for the value of scientific research as a national endeavor and as a foundation for industrial growth. The National Research Council, which had been founded in 1916 as a conduit of government funds to academic institutions but had been hobbled by political infighting and academic mistrust, became revivified in the postwar years. Universities that had shown their value during the war, such as Berkeley, stood at the head of the line for grants for faculty research and laboratory construction. Academia was just beginning to sense the United States government’s potential heft as a patron of scientific research.

  The man given the task of boosting Berkeley’s academic stature was William Wallace Campbell, who became its president in 1923. One of the nation’s leading astronomers, Campbell had been director of the university’s Lick Observatory for twenty-three years. He had been a major figure in one of the great scientific dramas of the 1920s, the quest to confirm Einstein’s theory of relativity by astronomical observation. The theory predicted that light reaching the Earth from distant stars would be bent by the gravitational field of the sun to a much greater degree than was predicted by classical Newtonian physics. The phenomenon would appear as an apparent shift in the location of the stars, if they could be observed in close proximity to the sun during a solar eclipse, when the darkening of the sun’s disk would make them visible. This was solidly within the expertise of Campbell, who, since 1898, had made a half dozen eclipse expeditions to remote locations in India, the Ukraine, and the South Pacific island of Kiribati, sponsored by the Lick and backed financially by the California railroad magnate Charles Frederick Crocker.

  Bad weather confounded the relativity observations during a Lick expedition to Brazil in 1918, forcing Campbell to concede the honor of confirming relativity to the British astronomer Arthur Eddington, based on his observations from the African island of Príncipe. But Campbell achieved the final confirmation, made in September 1922 from the northwestern coast of Australia.

  Campbell could not disagree with Europeans’ condescending view of American science as a backwater rich in money and manpower but poor in theoretical understanding. Every year, he dispatched his most promising graduate astronomers to the great European centers of scientific learning, such as Cambridge, Manchester, Paris, or Göttingen, Germany. These were the obligatory so-called Studienreisen, or study tours, their goal being the students’ acquisition of the necessary grounding in “the modern developments in Physics” that was simply unattainable in the United States. Campbell felt the deficiency all the more sharply between 1914 and 1918, when the Great War cut off all travel to Britain and the continent.

  In the postwar years, when an influx of demobilized students threatened to burst the seams of Berkeley’s outdated scientific facilities, California’s legislature and the university’s private patrons responded with unprecedented generosity. One spur surely was the 1921 transformation of Throop Polytechnic Institute, a modest private technical school in Pasadena, into the California Institute of Technology. The upgrade was the brainchild of the eminent astronomer George Ellery Hale. The money came from Hale’s cadre of loyal philanthropic backers, and the institution’s sudden leap into the first rank of universities worldwide was certified by its recruitment of Nobel laureate Robert A. Millikan, then the head of the University of Chicago, to become its president.

  Not to be outdone, Berkeley unveiled the centerpiece of its surge of spending in 1924. On the day it opened, LeConte Hall, named after John LeConte, a physicist and the very first faculty member appointed upon the founding of the university in 1869, was one of the largest physics buildings in the world. But filling its spacious offices and laboratories with appropriately distinguished professors was not as easy as getting the structure built. In vain, the university put out feelers to Niels Bohr, American Nobel laureate Arthur Holly Compton (who accepted an offer to become physics chairman but reneged after receiving a counteroffer from the University of Chicago)—even Swann.

  The department placed its quandary in the hands of two junior professors, Loeb and Raymond T. Birge, who devised a new strategy of snaring scientific prodigies on their way up, before they had a chance to cement themselves into comfortable sinecures elsewhere. As source material, they mined the roster of National Research Fellows. The fellowships had been established by the National Research Council to support candidates from among the top 5 percent of PhDs in the country, making it an invaluable guide to a prospective candidate’s scientific ability. They compiled a wish list of a half dozen candidates, among them the young Yale instructor widely considered back East to be the best of the current crop of fellows: Ernest O. Lawrence.

  After Loeb made the initial contact with Lawrence in Washington, Birge took over. He peppered Lawrence with pointed gossip about rival institutions that might have designs on him. “I got the following apparently authentic information about Cornell, which may interest you,” he informed Ernest in one letter. “Richtmeyer is very much at outs with the rest of the Dept. and is very unhappy there . . . I should advise you to stay at Yale. (For the present, at least.)” Birge’s misspelled reference presumably was to one of two eminent physicists, Floyd K. Richtmyer, a long-term professor at Cornell, or his son Robert, who was just coming to the end of his graduate education at the university but soon moved on to MIT.

  • • •

  That summer, in 1927, Lawrence joined Beams on a visit to Europe, where Swann was spending a sabbatical. It was Lawrence’s first visit abroad. The young scientists’ expectation was that Swann would escort them around Europe, introducing them to his friends and acquaintances among the eminent figures of European science in a sort of belated and truncated Studienreise.

  Promptly after greeting them in Paris, however, Swann deserted them in favor of a master class with the cellist Pablo Casals. So they spent the summer making their own frugal way among the scientific landmarks of Europe. They stopped at Niels Bohr’s Institute for Theoretical Physics at the University of Copenhagen. But the great man was not in attendance, and they contented themselves with walking its halls almost as tourists. In Berlin and Göttingen, they had cordial meetings with leading physicists; in Paris, they met Swann’s friend Marie Curie at her Radium Institute, where despite support from the French government and philanthropists in Europe and the United States, she was working with almost shockingly simple, even unsophisticated equipment—certainly nothing approaching the quality of furnishings they worked with at Yale. The same impression struck them in Britain, where the most groundbreaking advances were being achieved in Manchester and Cambridge with the most modest handmade gear.

  Small science was in its glory. Ernest did not at that moment absorb the lesson that high-quality research and solid theoretical reasoning could yield wonders, even with poor equipment, while even the best-furnished lab would produce little of value if the equipment was not deployed intelligently; he would have to learn the hard way. Yet he came away feeling that the Europeans had less to teach him and Beams than he had expected. The United States is “not behind except in fame,” he groused to Beams. It would not be long, he predicted, before Europeans would be coming to the United States for their Studienreisen.

  Upon returning home, Ernest found a letter from Birge portraying Berkeley as an academic paradise on earth. “Now I have an idea that you will like California and California will like you,” he wrote, making sure to emphasize that “the teaching schedules are as light here as any place in the country . . . far lighter than those of the average state University, and apparently far lighter than at Yale.” Birge’s goa
l was to wean Lawrence from Yale’s aura of prestige, which could seem overwhelming compared with that of a distant public university. Nor was Yale allowing the bidding for Lawrence to go unanswered. Just before his departure for Europe, the university had granted him an assistant professorship at a salary of $3,000. Beams, for one, was convinced that Yale would never let Lawrence go.

  Not so Birge, who kept up the pressure on a young man he perceived to be in a hurry. “The . . . chance to get somewhere in reasonable time is everything,” he wrote Lawrence to reinforce a firm offer from physics chairman Elmer Hall of an associate professor’s post paying $3,300, not counting a faculty-wide raise of $500 due in the coming year. At Berkeley, Birge assured him, “the younger men now are being appointed and advanced on an entirely different plane from that of the older men.” And that was for ordinary talents. “You are not at all concerned with the average scale at this or other universities or with the average rate of promotion . . . I think you are concerned only in the way the exceptional men are treated. I doubt if any man has ever been offered the permanent position of Asso. Prof. at this University with as short a period of teaching and research experience as in your case. That proves . . . how highly we regard you.”

  Two factors finally prompted Ernest to cut the cord with Yale. One was Swann’s decision to accept the directorship of the small, poorly funded Bartol Research Institute of Philadelphia. The second was Yale’s complacent refusal to accommodate its sought-after assistant professor’s request for a promotion to associate professor. Such rapid advancement cut against the grain in New Haven. Ernest’s academic superiors were unable to see past his youth, much less rid themselves of the conviction that faculty members simply did not leave Yale to accept positions at state universities on the distant West Coast. Beams, who was one of the first members of Lawrence’s circle to learn that he was accepting Berkeley’s offer, marched into physics chairman John Zeleny’s office to announce that Yale was about to commit “the biggest mistake they ever made.” Zeleny replied funereally that he agreed but could not convince the dean. On March 12, 1928, Lawrence accepted the Berkeley offer by telegram.

  That summer, just before motoring across country to take up his new post, he stopped in Washington to see Merle Tuve. Merle had received his doctorate from Johns Hopkins University and been ensconced for two years at the Department of Terrestrial Magnetism of the Carnegie Institution of Washington, Swann’s former haunt. There he was immersed in an effort to produce high-energy protons to probe the atomic nucleus, using his balky Tesla coils and Van de Graaff generators. Inside his lab, amid the stink of petroleum fumes and the clatter of motors, Tuve asked Lawrence what research he intended to do at Berkeley, and got what he thought was a woolly answer.

  “He responded, rather vaguely, with some small notions about high-speed rotating mirrors, chopping the tails off quanta and other single-shot ideas,” Tuve would recall. It was the old Ernie Lawrence, distracted by gadgetry and apparatus instead of burying his nose in scientific journals.

  Tuve upbraided Lawrence with all the authority of his six weeks’ advantage in age and with all the frank liberty afforded to one childhood friend speaking to another. “I said it was high time for him to quit selecting research problems like choosing cookies at a party; it was time for him to pick a field of research that was full of fresh questions to be answered.” The right choice was inescapable. “Any undergraduate could see that nuclear physics using artificial beams of high-energy protons and helium ions was such a field, and . . . he should stake out a territory there to work and grow in.”

  Lawrence listened soberly, his eyes wandering over the magnets, Tesla coils, and vacuum tubes littering the lab. “He was vaguely searching for an identifiable field full of specific problems,” Tuve concluded. Tuve could not have known it at that moment, but he had set his friend on the path to a career.

  Chapter Three

  * * *

  “I’m Going to Be Famous”

  For such a seminal moment in a field that demands rigorous procedural records, the full circumstances of the cyclotron’s birth remain frustratingly indistinct. We know that Ernest Lawrence acquired the basic idea from an article in an obscure German technical journal, and we know the journal, the article, and its author. We know that the moment occurred in the spring of 1929, though the exact date is murky.

  We know less about what prompted Lawrence to pick up the journal and page through it. Had he been pondering the question of how to accelerate particles for a long time, or did the concept that was to guide his life’s work occur to him on the spot? His contemporaries are divided on the question, and his own notes are contradictory. Did he come upon the Archiv für Elektrotechnik issue for December 19, 1928, in the Berkeley science stacks utterly by chance, or was the journal there because he himself had ordered the subscription? There is evidence for both possibilities. Did he happen on the article by the Norwegian physicist Rolf Wideröe while “glancing over current periodicals in the University library,” as he related in his Nobel Prize acceptance speech? Or did he stumble upon it while trying to stave off the boredom of an interminable faculty meeting, as he told Wideröe at their only face-to-face meeting many years later?

  What is agreed upon is that Lawrence understood almost immediately the import of what he had seen, even though Wideröe’s report was written in dense technical German, a language that was largely beyond Ernest’s ken. “I merely looked at the diagrams and photographs,” he said in his Nobel speech. From these, he gleaned that Wideröe’s “general approach” was to accelerate ions on a straight line by delivering to them repeated kicks from a series of charged electrical gaps. For Lawrence, the stepwise acceleration of particles by multiple small impulses “immediately impressed me as the real answer which I had been looking for to the technical problem of accelerating positive ions.” More precisely, it appeared to solve the problem of how to produce high-energy particles without applying high voltages. Laying aside the article, he sketched out a linear accelerator to drive protons to a million volts, the first major step toward satisfying Ernest Rutherford’s demand for 10 million volts. Yet he was not quite at the goal: simple math told him that reaching that energy would require a linear tube many meters in length—“rather awkwardly long for laboratory purposes.”

  Then came the real brainstorm. What if he could force ions into a circular path, thereby passing them repeatedly across a single electrical gap? This conception of a compact and electrically efficient accelerator synthesized several established principles into a novel whole. The first principle was that charged particles moving in a perpendicular direction through a magnetic field follow a curved path. The challenge then becomes timing the electrical impulses so they energize the gap at the very moment the particles cross, which means generating them from an oscillator working at a fixed frequency.

  The second principle—and this was so crucial it became known as the “cyclotron principle”—was that as the particles gain speed, their paths spiral wider. This lengthens the distance they must travel to return to the starting point; but the increase in speed and the lengthening of the path work together, so that as they move faster on the longer path, they will still reach the gap at the same interval. This principle resembles that by which a point on the rim of a bicycle remains in sync with a point on the hub, even though with each rotation of the wheel the point on the rim travels several feet and the point on the hub only a few inches.

  Put the principles together, and they indicate that an electrical field at a constant frequency can impart repeated kicks to a stream of spiraling protons without being constantly retuned. The phenomenon by which protons keep time with the oscillator even as they accelerate came to be known as “resonance.” To accelerator designers, it is a principle as fundamental as Einstein’s E=mc2.

  The cyclotron principle was not exactly unknown to physics. Earlier in 1929, the Hungarian physicist Leo Szilard, whose fertile mind produced a stream of fanciful devices in the twenties a
nd thirties, had attempted to obtain a patent in Germany for an apparatus based on the idea. But his design was too vague and perhaps too revolutionary to convince the examiners. For all his creativity, Szilard lacked the tenacity of an Ernest Lawrence, as he acknowledged years later. “The merit,” he told a friend, “lies in the carrying out and not the thinking out of the experiment.” To Szilard, his device was one of many ideas that might or might not work; to Ernest Lawrence, it was an idea upon which to build a career.

  Ernest sprinted back to his bachelor quarters at Berkeley’s Faculty Club to share his theory with his fellow residents, most of them unmarried junior faculty members like himself. As a rule, Lawrence was not a boisterous sort, but they had all at one time or another witnessed his ebullient outbursts when he was seized with a new idea. Many of them would retain lifelong memories of the first time they heard Ernest Lawrence describe the cyclotron. Tom Johnson would recall hearing Lawrence describe it in the Berkeley library that first night, the Wideröe paper clutched in his hands. At the Faculty Club, the first person Lawrence encountered was Donald Shane, a mathematician who obligingly double-checked Lawrence’s scribbled calculations and agreed that the math appeared to be sound.

  “But what are you going to do with it?” Shane asked.

  “I’m going to break up atoms!” came the reply.

  Lawrence was still on the boil the next day. One faculty wife would always remember his exclamation when she encountered him on a wooded walkway as Berkeley was waking up to a chilly spring morning: he shouted at her, “I’m going to be famous!” Jim Brady, one of his graduate students, was tinkering at his lab table on the second floor of LeConte when Ernest bounded in, dragged Brady to the blackboard, and sketched out the equations. Tuve’s electrostatic accelerator would produce high voltages, all right, Lawrence told Brady. “But what can they do with them when they get them?” he asked. If you put a million volts into a vacuum tube, you could be sure only of blasting the tube to bits. But if you put a few thousand volts on the tube and built up to a million volts on the particles, the glassware would survive, and the particles would accelerate.