Glauber, Roy Jay (1925-2018), was an American physicist. He won a share of the 2005 Nobel Prize in physics for developing a mathematical description of the behavior of light. Glauber’s work formed part of a branch of physics called quantum mechanics. Glauber shared the prize with physicists John L. Hall of the United States and Theodor W. Hansch of Germany, who devised more precise methods of using lasers in measurement.
In the century before the development of quantum mechanics in the early 1900’s, most physicists described light as a wave. Quantum mechanics revealed that light can also act as a particle called a photon. Physicists soon worked out mathematical models to describe the behavior of a single photon and small groups of photons. However, they continued to rely on traditional models of wave motion to explain the much more complex behavior of large numbers of photons. This approach proved sufficiently accurate for most light sources, which emit (give off) a scattered jumble of photons called incoherent light. The fairly random manner in which these photons are emitted tends to conceal quantum mechanical effects, producing results similar to those predicted by wave models.
Glauber’s breakthrough began with his study of a mid-1950’s experiment in which astronomers used detectors to count photons emitted by the star Sirius. The astronomers found that the photons did not arrive in the random manner predicted by traditional wave models. Glauber explained this observation in a theory published in 1963. In developing the theory, Glauber had worked out a quantum mechanical model capable of describing the behavior of large numbers of photons. This model could accurately explain both incoherent light and coherent light, highly organized light, such as that produced by lasers. Many scholars consider Glauber’s work the foundation of quantum optics, the quantum mechanical study of the properties of light.
Glauber was born Sept. 1, 1925, in New York City. From 1944 to 1946, he worked as a member of the Manhattan Project, the team of U.S. scientists that developed the first atomic bomb. Glauber studied physics at Harvard University in Cambridge, Massachusetts, earning a Ph.D. degree in 1949. He conducted research at the Institute for Advanced Study in Princeton, New Jersey, from 1949 to 1951 and at the California Institute of Technology in Pasadena in 1951 and 1952. In 1952, he joined the faculty at Harvard where he spent the rest of his career. He died on Dec. 26, 2018.
See also Hall, John Lewis ; Hansch, Theodor Wolfgang ; Laser (Characteristics of laser light); Light (The nature of light; Photons); Quantum mechanics .
