Ernest Lawrence
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| Ernest Lawrence |
A graduate of the University of South Dakota and University of Minnesota, Lawrence obtained a PhD in physics at Yale in 1925. In 1928, he was hired as an associate professor of physics at the University of California, becoming the youngest full professor there two years later. In its library one evening, Lawrence was intrigued by a diagram of an accelerator that produced high-energy particles. He contemplated how it could be made compact, and came up with an idea for a circular accelerating chamber between the poles of an electromagnet. The result was the first cyclotron.
Lawrence went on to build a series of ever larger and more expensive cyclotrons. His Radiation Laboratory became an official department of the University of California in 1936, with Lawrence as its director. In addition to the use of the cyclotron for physics, Lawrence also supported its use in research into medical uses of radioisotopes. During World War II, Lawrence developed electromagnetic isotope separation at the Radiation Laboratory. It used devices known as calutrons, a hybrid of the standard laboratory mass spectrometer and cyclotron. A huge electromagnetic separation plant was built at Oak Ridge, Tennessee, which came to be called Y-12. The process was inefficient, but it worked.
After the war, Lawrence campaigned extensively for government sponsorship of large scientific programs, and was a forceful advocate of "Big Science", with its requirements for big machines and big money. Lawrence strongly backed Edward Teller's campaign for a second nuclear weapons laboratory, which Lawrence located in Livermore, California. After his death, the Regents of the University of California renamed the Lawrence Livermore National Laboratory and Lawrence Berkeley National Laboratory after him. Chemical element number 103 was named lawrencium in his honor after its discovery at Berkeley in 1961.
Early life
Ernest Orlando Lawrence was born in Canton, South Dakota on August 8, 1901. His parents, Carl Gustavus and Gunda (née Jacobson) Lawrence, were both the offspring of Norwegian immigrants who had met while teaching at the high school in Canton, where his father was also the superintendent of schools. He had a younger brother, John H. Lawrence, who would become a physician, and was a pioneer in the field of nuclear medicine. Growing up, his best friend was Merle Tuve, who would also go on to become a highly accomplished nuclear physicist.
Lawrence attended the public schools of Canton and Pierre, then enrolled at St. Olaf College in Northfield, Minnesota, but transferred after a year to the University of South Dakota in Vermillion.He completed his bachelor's degree in chemistry in 1922,and his Master of Arts (M.A.) degree in physics from the University of Minnesota in 1923 under the supervision of William Francis Gray Swann. For his master's thesis, Lawrence built an experimental apparatus that rotated an ellipsoid through a magnetic field.
Lawrence followed Swann to the University of Chicago, and then to Yale University in New Haven, Connecticut, where Lawrence completed his Doctor of Philosophy (Ph.D.) degree in physics in 1925 as a Sloane Fellow,writing his doctoral thesis on the photoelectric effect in potassium vapor.He was elected a member of Sigma Xi, and, on Swann's recommendation, received a National Research Council fellowship. Instead of using it to travel to Europe, as was customary at the time, he remained at Yale University with Swann as a researcher.
With Jesse Beams from the University of Virginia, Lawrence continued to research the photoelectric effect. They showed that photoelectrons appeared within 2 x 10-9 seconds of the photons striking the photoelectric surface—close to the limit of measurement at the time. Reducing the emission time by switching the light source on and off rapidly made the spectrum of energy emitted broader, in conformance with Werner Heisenberg's uncertainty principle.
Early career
In 1926 and 1927, Lawrence received offers of assistant professorships from the University of Washington in Seattle and the University of California at a salary of $3,500 per annum. Yale promptly matched the offer of the assistant professorship, but at a salary of $3,000. Lawrence chose to stay at the more prestigious Yale,but because he had never been an instructor, the appointment was resented by some of his fellow faculty, and in the eyes of many it still did not compensate for his South Dakota immigrant background.
Lawrence was hired as an associate professor of physics at the University of California in 1928, and two years later became a full professor, becoming the university's youngest professor.Robert Gordon Sproul, who became university president the day after Lawrence became a professor,was a member of the Bohemian Club, and he sponsored Lawrence's membership in 1932. Through this club, Lawrence met William Henry Crocker, Edwin Pauley, and John Francis Neylan. They were influential men who helped him obtain money for his energetic nuclear particle investigations. There was great hope for medical uses to come from the development of particle physics, and this led to much of the early funding for advances Lawrence was able to obtain.
While at Yale, Lawrence met Mary Kimberly (Molly) Blumer, the eldest of four daughters of George Blumer, the dean of the Yale School of Medicine.They first met in 1926 and became engaged in 1931,and were married on May 14, 1932, at Trinity Church on the Green in New Haven, Connecticut.They had six children: Eric, Margaret, Mary, Robert, Barbara, and Susan.Lawrence named his son Robert after theoretical physicist Robert Oppenheimer, his closest friend in Berkeley.In 1941, Molly's sister Elsie married Edwin McMillan,who would go on to win the Nobel Prize in Chemistry in 1951.
Development
Six men in suits sitting on chairs, smiling and laughing
Meeting at Berkeley in 1940 concerning the planned 184-inch (4.67 m) cyclotron (seen on the blackboard): Lawrence, Arthur Compton, Vannevar Bush, James B. Conant, Karl T. Compton, and Alfred Lee Loomis
In what would become a recurring pattern, as soon as there was the first sign of success, Lawrence started planning a new, bigger machine. Lawrence and Livingston drew up a design for a 27-inch (69 cm) cyclotron in early 1932. The magnet for the $800 11-inch cyclotron weighed 2 tons, but Lawrence found a massive 80-ton magnet rusting in a junkyard in Palo Alto for the 27-inch that had originally been built during World War I to power a transatlantic radio link.In the cyclotron, he had a powerful scientific instrument, but this did not translate into scientific discovery. In April 1932, John Cockcroft and Ernest Walton at the Cavendish Laboratory in England announced that they had bombarded lithium with protons and succeeded in transmuting it into helium. The energy required turned out to be quite low—well within the capability of the 11-inch cyclotron. On learning about it, Lawrence sent a wire to Berkeley and asked for Cockcroft and Walton's results to be verified. It took the team until September to do so, mainly due to lack of adequate detection apparatus.
Although important discoveries continued to elude Lawrence's Radiation Laboratory, mainly due to its focus on the development of the cyclotron rather than its scientific use, through his increasingly larger machines, Lawrence was able to provide crucial equipment needed for experiments in high energy physics. Around this device, he built what became the world's foremost laboratory for the new field of nuclear physics research in the 1930s. He received a patent for the cyclotron in 1934,which he assigned to the Research Corporation,a private foundation that funded much of Lawrence's early work.
In February 1936, Harvard University's president, James B. Conant, made attractive offers to Lawrence and Oppenheimer.The University of California's president, Robert Gordon Sproul responded by improving conditions. The Radiation Laboratory became an official department of the University of California on July 1, 1936, with Lawrence formally appointed its director, with a full-time assistant director, and the University agreed to make $20,000 a year available for its research activities.Lawrence employed a simple business model: "He staffed his laboratory with graduate students and junior faculty of the physics department, with fresh Ph.D.s willing to work for anything, and with fellowship holders and wealthy guests able to serve for nothing."
Reception
Using the new 27-inch cyclotron, the team at Berkeley discovered that every element that they bombarded with recently discovered deuterium emitted energy, and in the same range. They therefore postulated the existence of a new and hitherto unknown particle that was a possible source of limitless energy.William Laurence of The New York Times described Lawrence as "a new miracle worker of science".At Cockroft's invitation, Lawrence attended the 1933 Solvay Conference in Belgium. This was a regular gathering of the world's top physicists. Nearly all were from Europe, but occasionally an outstanding American scientist like Robert A. Millikan or Arthur Compton would be invited to attend. Lawrence was asked to give a presentation on the cyclotron.Lawrence's claims of limitless energy met a very different reception in Solvay. He ran into withering skepticism from the Cavendish Laboratory's James Chadwick, the physicist who had discovered the neutron in 1932, for which he had been awarded the Nobel Prize in 1935. To Chadwick, what Lawrence was doing was not Big Science but Bad Science. In a British accent that sounded condescending to American ears, Chadwick suggested that what Lawrence's team was observing was contamination of their apparatus.
Six men in suits and ties stand stand in front of gigantic machinery. Two more are sitting in top of it.
The 60-inch (1.52 m) cyclotron soon after completion in 1939. The key figures in its development and use are shown, standing, left to right: D. Cooksey, D. Corson, Lawrence, R. Thornton, J, Backus, W.S. Sainsbury. In the background are Luis Walter Alvarez and Edwin McMillan.
When he returned to Berkeley, Lawrence mobilized his team to go painstakingly over the results to gather enough evidence to convince Chadwick. Meanwhile, at the Cavendish laboratory, Rutherford and Mark Oliphant found that deuterium fuses to form helium-3, which causes the effect that the cyclotroneers had observed. Not only was Chadwick correct in that they had been observing contamination, but they had overlooked yet another important discovery, that of nuclear fusion.Lawrence's response was to press on with the creation of still larger cyclotrons. The 27-inch cyclotron was superseded by a 37-inch cyclotron in June 1937,which in turn was superseded by a 60-inch cyclotron in May 1939. It was used to bombard iron and produced its first radioactive isotopes in June.
As it was easier to raise money for medical purposes, particularly cancer treatment, than for nuclear physics, Lawrence encouraged the use of the cyclotron for medical research. Working with his brother John and Israel Lyon Chaikoff from the University of California's Physiology Department, Lawrence supported research into the use of radioactive isotopes for therapeutic purposes. Phosphorus-32 was easily produced in the cyclotron, and John used it to cure a woman afflicted with polycythemia vera, a blood disease. John used phosphorus-32 created in the 37-inch cyclotron in 1938 in tests on mice with leukemia. He found that the radioactive phosphorus concentrated in the fast-growing cancer cells. This then led to clinical trials on human patients. A 1948 evaluation of the therapy showed that remissions occurred under certain circumstances.Lawrence also had hoped for the medical use of neutrons. The first cancer patient received neutron therapy from the 60-inch cyclotron on November 20.Chaikoff conducted trials on the use of radioactive isotopes as radioactive tracers to explore the mechanism of biochemical reactions.
Lawrence was awarded the Nobel Prize in Physics in November 1939 "for the invention and development of the cyclotron and for results obtained with it, especially with regard to artificial radioactive elements".He was the first at Berkeley as well as the first South Dakotan to become a Nobel Laureate, and the first to be so honored while at a state-supported university. The award ceremony was held on February 29, 1940, in Berkeley, California due to World War II, in the auditorium of Wheeler Hall on the campus of the university. Lawrence received his medal from Carl E. Wallerstedt, Sweden's Consul General in San Francisco.Robert W. Wood wrote to Lawrence and presciently noted "As you are laying the foundations for the cataclysmic explosion of uranium ... I'm sure old Nobel would approve."
In March 1940, Arthur Compton, Vannevar Bush, James B. Conant, Karl T. Compton, and Alfred Lee Loomis traveled to Berkeley to discuss Lawrence's proposal for a 184-inch cyclotron with a 4,500-ton magnet that was estimated to cost $2.65 million. The Rockefeller Foundation put up $1.15 million to get the project started.
Death and legacy
In addition to the Nobel Prize, Lawrence received the Elliott Cresson Medal and the Hughes Medal in 1937, the Comstock Prize in Physics in 1938, the Duddell Medal and Prize in 1940, the Holley Medal in 1942, the Medal for Merit in 1946, the William Procter Prize in 1951, Faraday Medal in 1952,and the Enrico Fermi Award from the Atomic Energy Commission in 1957.He was made an Officer of the Legion d'Honneur in 1948,and was the first recipient of the Sylvanus Thayer Award by the US Military Academy in 1958.
In July 1958, President Dwight D. Eisenhower asked Lawrence travel to Geneva, Switzerland, to help negotiate a proposed Partial Nuclear Test Ban Treaty with the Soviet Union. AEC Chairman Lewis Strauss had pressed for Lawrence's inclusion. The two men had argued the case for the development of the hydrogen bomb, and Strauss had helped raise funds for Lawrence's cyclotron in 1939. Strauss was keen to have Lawrence as part of the Geneva delegation because Lawrence was known to favor continued nuclear testing.Despite suffering from a serious flare-up of his chronic ulcerative colitis, Lawrence decided to go, but he became ill while in Geneva, and was rushed back to the hospital at Stanford University.Surgeons removed much of his large intestine, but found other problems, including severe atherosclerosis in one of his arteries.He died in Palo Alto Hospital on August 27, 1958.Molly did not want a public funeral, but agreed to a memorial service at the First Congregationalist Church in Berkeley. University of California President Clark Kerr delivered the eulogy.
Just 23 days after his death, the Regents of the University of California voted to rename two of the university's nuclear research sites after Lawrence: the Lawrence Livermore National Laboratory and the Lawrence Berkeley National Laboratory.The Ernest Orlando Lawrence Award was established in his memory in 1959.Chemical element number 103, discovered at the Lawrence Berkeley National Laboratory in 1961, was named lawrencium after him.In 1968 the Lawrence Hall of Science public science education center was established in his honor.His papers are in the Bancroft Library at the University of California in Berkeley.In the 1980s, Lawrence's widow petitioned the University of California Board of Regents on several occasions to remove her husband's name from the Livermore Laboratory, due to its focus on nuclear weapons Lawrence helped build, but was denied each time.She outlived her husband by more than 44 years and died in Walnut Creek at the age of 92 on January 6, 2003.George B. Kauffman wrote that:
Before him, "little science" was carried out largely by lone individuals working with modest means on a small scale. After him, massive industrial, and especially governmental, expenditures of manpower and monetary funding made "big science," carried out by large-scale research teams, a major segment of the national economy.
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