Norman F. Ramsey

American physicist

• Born: August 27, 1915; Washington, DC
• Died: November 4, 2011; Wayland, Massachusetts

American physicist Norman F. Ramsey was an influential researcher, teacher, and administrator. He contributed to the development of radar and the atomic bomb, served with a number of agencies, and won the Nobel Prize for the Ramsey method of separated oscillatory fields.

PRIMARY FIELD: Physics

SPECIALTIES: Atomic and molecular physics; nuclear physics; quantum mechanics; theoretical physics

Early Life

Norman Foster Ramsey Jr. was the son of West Point graduate and Army Ordnance officer Norman Foster Ramsey Sr. and university mathematics instructor Minna Bauer Ramsey. Because of his father’s occupation, Ramsey grew up in a variety of places, including Washington, DC; Paris, France; New Jersey; and Kansas. An exceptionally bright student interested in the sciences, he skipped two grades during his early education before graduating at age fifteen from Fort Leavenworth High School in Kansas. Though his father hoped his son would attend West Point, at graduation in 1930, Ramsey was too young to enroll.

Ramsey was awarded a scholarship to Kansas University, but his parents moved in 1930 to New York City. In 1931, he entered Columbia College (later Columbia University) to major in engineering. Ramsey soon switched to mathematics. A perennial winner of math contests, he was allowed in his senior year to become a teaching assistant, a position normally given to graduate students.

After earning a bachelor’s degree from Columbia in 1935, Ramsey used a scholarship to attend Cambridge University in England, where, as a physics student, he conducted research at the world-famous Cavendish Laboratory. Ramsey learned from leading physicists of the day, including many of whom were or would become Nobel laureates. Among his teachers were Edward Victor Appleton, Max Born, Edward Crisp Bullard, James Chadwick, John Cockcroft, Paul Dirac, Arthur Stanley Eddington, Ralph Howard Fowler, Maurice Goldhaber, Ernest Rutherford, and Joseph John Thompson.

Ramsey received a second bachelor’s degree from Cambridge in 1937 and returned to Columbia to conduct molecular beam research with Austrian-born physicist Isidor Isaac Rabi. Ramsey received his PhD in physics in 1940.

Life’s Work

After earning his doctoral degree, Ramsey studied in Washington, DC, on a Carnegie Institution fellowship. That same year, he married Elinor Jameson, and the couple soon left for the University of Illinois, where a teaching position awaited Ramsey. With World War II already raging in Europe, however, he was asked to participate in an important wartime project and returned to the East Coast. For the next two years, he was at the Massachusetts Institute of Technology (MIT) in Cambridge, Massachusetts, as director of a group that developed microwave radar, a type of electromagnetic energy used for detecting objects. Ramsey contributed British magnetrons—tubes that magnetically control the flow of electrons to generate power—to the laboratory, where they could be replicated and refined. He afterward served in Washington, DC, as an expert radar consultant to Henry L. Stimson, US secretary of war under Franklin D. Roosevelt.

In 1943, Ramsey was tapped as a member of another wartime program: the Manhattan Project, the code name given to the development of the atomic bomb. Ramsey was a member of Project Alberta, which was tasked with perfecting the shape, configuration, and method of delivery of nuclear devices to their eventual targets, Hiroshima and Nagasaki, Japan. In experiments, Ramsey noticed that heavy bombs tumbled when dropped from high altitude, a condition that adversely affected their accuracy. The tumbling was caused by stresses that crumpled bomb fins. Ramsey devised simple fin reinforcements, called drag plates, that made bombs drop straight and on target.

Following the end of the war, Ramsey returned to Columbia as a professor of physics and research scientist, working alongside Rabi in the investigation of molecular beams via spectroscopy. In 1947, Ramsey and Rabi cofounded Brookhaven National Laboratory on Long Island, New York, initially a US Atomic Energy Commission (AEC) research facility, now operated under the aegis of the US Department of Energy. Ramsey served as the first head of the physics department at Brookhaven.

In 1947, Ramsey left Columbia for Harvard University, where he remained as physics professor for the next forty years, though he took frequent leaves of absence to serve in a variety of capacities with a number of organizations. For example, he was a visiting professor at such institutions as Oxford University in England, Middlebury College in Vermont, and the University of Virginia. He also helped establish a molecular beam laboratory at Harvard. There, he carried out proton scattering and magnetic resonance experiments, which helped lead to his invention of the oscillatory field method, subsequently called the separated Ramsey method, a breakthrough that later brought him a share of the 1989 Nobel Prize in Physics. Employing the Ramsey method, Ramsey was able to develop the hydrogen maser in 1960, a device that uses atomic frequencies to make accurate measurements.

In the late 1940s and early 1950s, Ramsey was science advisor to the North Atlantic Treaty Organization, in which post he instituted numerous fellowship and research grants. During the same time period, he oversaw the building of the Harvard Cyclotron Laboratory—completed in 1949—and directed the lab in its startup years.

Ramsey in the late 1950s and early 1960s served as chair of a committee managing the construction of the Cambridge Electron Accelerator (CEA). The CEA, funded by the AEC, was a joint Harvard–MIT project completed in 1960 and in operation until 1974. The CEA was used for high-energy physics experiments, such as electron-proton scattering.

Between the mid-1960s and early 1980s, Ramsey was president of the Universities Research Association (URA), a Washington-based organization consisting of more than eighty research universities in the United States, Canada, Italy, and Japan. Under Ramsey’s leadership, URA managed the construction and operation of the US Department of Energy–funded Fermi National Accelerator Laboratory—known worldwide as Fermilab—that opened in 1967 outside Chicago, Illinois.

In 1968, Ramsey served as chair of the highly influential General Advisory Committee of the AEC, which set national policy for both peaceful and military uses of nuclear power. Among other organizations with which Ramsey was affiliated were the Carnegie Endowment for International Peace (trustee, 1962–1986), the American Physical Society (president, 1978–1979), the American Institute of Physics (chairman, board of governors, 1980–1986), and the National Research Council (chairman, board of physics and astronomy, 1985–1989).

Ramsey’s first wife, Elinor, died in 1983, after which he married Ellie Welch; the couple had a combined family of seven children and numerous grandchildren. In 1986, Ramsey officially retired, becoming professor emeritus at Harvard. He remained active in physics for years afterward, spending several seasons as a research/adjunct research fellow at the Joint Institute for Laboratory Astrophysics at the University of Colorado. He also served several stints as visiting professor at the University of Chicago, the University of Michigan, and Williams College in Williamstown, Massachusetts.

Author and coauthor of scores of scholarly papers and books from 1939 onward, Ramsey was honored often for his work. In addition to sharing the 1989 Nobel Prize, he received the Lawrence Award (1960), the Davisson-Germer Prize (1974), the IEEE Medal of Honor (1984), the Rabi Prize and Rumford Premium (1985), the Compton Medal (1986), the Oersted Medal (1988), and the National Medal of Science (1988).

Ramsey died in a nursing home on November 4, 2011, at the age of ninety-six.

Impact

A researcher, an administrator, and an inspiring teacher to dozens of advanced students, Ramsey was a colleague to some of the foremost teachers and investigators of molecular physics between the 1930s and the early twenty-first century.

Ramsey’s early experiments with microwave electromagnetic energy were crucial to the Allied efforts in World War II. In conjunction with British radiolocation research into longer wavelengths, the studies of Ramsey and others at the MIT Radiation Laboratory led to the development of radar for use in bombers, night fighters, and submarine-spotters. The accurate radar the laboratory produced was instrumental in the successful outcome of the Battle of Britain in 1940. Likewise, Ramsey’s role in the Manhattan Project was vital to the precise delivery of the atomic bombs that ended World War II. The drag plates he developed for making bombs drop on target were later adopted for other military hardware.

Ramsey’s Nobel Prize–winning separated oscillatory field method led to the development of the most precise type of clock—the maser atomic clock—and to other developments such as magnetic resonance imaging (MRI) therapy and the Global Positioning System (GPS).

Bibliography

Audoin, Claude, and Bernard Guinot. The Measurement of Time: Time, Frequency and the Atomic Clock. Trans. Stephen Lyle. Cambridge: Cambridge UP, 2001. Print.

Brodsky, Ira. The History and Future of Medical Technology. St. Louis: Telescope, 2010. Print.

Gordin, Michael D. Five Days in August: How World War II Became a Nuclear War. Princeton: Princeton UP, 2007. Print.

Hoffman, Jascha. “Norman Ramsey Dies at 96; Work Led to the Atomic Clock." The New York Times, 6 Nov. 2011, www.nytimes.com/2011/11/07/us/norman-ramsey-dies-at-96-work-led-to-the-atomic-clock.html. Accessed 11 Oct. 2024.

“Norman F. Ramsey." The Nobel Prize, www.nobelprize.org/prizes/physics/1989/ramsey/biographical/. Accessed 11 Oct. 2024.