Gregory Breit (russian: Григорий Альфредович Брейт-Шнайдер, ''Grigory Alfredovich Breit-Shneider''; July 14, 1899, Mykolaiv,

Kherson Governorate The Kherson Governorate (1802–1922; russian: Херсонская губерния, translit.: ''Khersonskaya guberniya''; uk, Херсонська губернія, translit=Khersonska huberniia), was an administrative territorial unit (als ...

– September 13, 1981, Salem, Oregon) was a Russian-born Jewish American

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...

and professor at

New York University New York University (NYU) is a private research university in New York City. Chartered in 1831 by the New York State Legislature, NYU was founded by a group of New Yorkers led by then- Secretary of the Treasury Albert Gallatin. In 1832, th ...

(1929–1934),

University of Wisconsin–Madison A university () is an institution of higher (or tertiary) education and research which awards academic degrees in several academic disciplines. Universities typically offer both undergraduate and postgraduate programs. In the United Stat ...

(1934–1947),

Yale University Yale University is a private research university in New Haven, Connecticut. Established in 1701 as the Collegiate School, it is the third-oldest institution of higher education in the United States and among the most prestigious in the w ...

(1947–1968), and University at Buffalo (1968–1973). In 1921, he was

Paul Ehrenfest Paul Ehrenfest (18 January 1880 – 25 September 1933) was an Austrian theoretical physicist, who made major contributions to the field of statistical mechanics and its relations with quantum mechanics, including the theory of phase transition ...

's assistant in

Leiden University Leiden University (abbreviated as ''LEI''; nl, Universiteit Leiden) is a public research university in Leiden, Netherlands. The university was founded as a Protestant university in 1575 by William, Prince of Orange, as a reward to the city o ...

Biography

After completing his Ph.D. at age 22, he was from 1923 to 1924 an assistant professor at the

University of Minnesota The University of Minnesota, formally the University of Minnesota, Twin Cities, (UMN Twin Cities, the U of M, or Minnesota) is a public land-grant research university in the Twin Cities of Minneapolis and Saint Paul, Minnesota, United States. ...

. In 1925, while at the Carnegie Institution of Washington, Breit joined with

Merle Tuve Merle Anthony Tuve (June 27, 1901 – May 20, 1982) was an American geophysicist who was the Chairman of the Office of Scientific Research and Development's Section T, which was created in August 1940. He was founding director of the Johns Hopkins ...

in using a pulsed radio transmitter to determine the height of the

ionosphere The ionosphere () is the ionized part of the upper atmosphere of Earth, from about to above sea level, a region that includes the thermosphere and parts of the mesosphere and exosphere. The ionosphere is ionized by solar radiation. It plays ...

, a technique important later in

radar Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, Marine radar, ships, spacecraft, guided missiles, motor v ...

development. Together with Eugene Wigner, Breit gave a description of particle resonant states with the

relativistic Breit–Wigner distribution The relativistic Breit–Wigner distribution (after the 1936 nuclear resonance formula of Gregory Breit and Eugene Wigner) is a continuous probability distribution with the following probability density function, SePythia 6.4 Physics and Manual(page ...

in 1929, and with Edward Condon, he first described proton-proton dispersion. He is also credited with deriving the Breit equation. The Breit frame of reference is named after him. He was one of the first to notice the

zitterbewegung In physics, the zitterbewegung ("jittery motion" in German, ) is the predicted rapid oscillatory motion of elementary particles that obey relativistic wave equations. The existence of such motion was first discussed by Gregory Breit in 1928 and la ...

(jittery motion) in the solutions of the Dirac equation. In 1934, together with

John A. Wheeler John Archibald Wheeler (July 9, 1911April 13, 2008) was an American theoretical physicist. He was largely responsible for reviving interest in general relativity in the United States after World War II. Wheeler also worked with Niels Bohr in e ...

, Breit described the

Breit–Wheeler process The Breit–Wheeler process or Breit–Wheeler pair production is a physical process in which a positron–electron pair is created from the collision of two photons. It is the simplest mechanism by which pure light can be potentially transformed ...

. In 1939 he was elected to the National Academy of Sciences. In April 1940, he proposed to the National Research Council that American scientists observe a policy of self-censorship due to the possibility of their work being used for military purposes by enemy powers in

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the World War II by country, vast majority of the world's countries—including all of the great power ...

. During the early stages of the war, Breit was chosen by

Arthur Compton Arthur Holly Compton (September 10, 1892 – March 15, 1962) was an American physicist who won the Nobel Prize in Physics in 1927 for his 1923 discovery of the Compton effect, which demonstrated the particle nature of electromagnetic radia ...

to supervise the early design of the first

atomic bomb A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission (fission bomb) or a combination of fission and fusion reactions ( thermonuclear bomb), producing a nuclear explosion. Both bomb ...

during an early phase in what would later become the

Manhattan Project The Manhattan Project was a research and development undertaking during World War II that produced the first nuclear weapons. It was led by the United States with the support of the United Kingdom and Canada. From 1942 to 1946, the project w ...

. Breit resigned his position in 1942, feeling that the work was going too slowly and that there had been security breaches on the project; his job went to Robert Oppenheimer, who was later appointed to scientific director of the entire project. In 2014, experimentalists proposed a way to validate an idea by Breit and

that matter formation could be achieved by interacting light particles ("

"). Breit was Associate Editor of the ''

Physical Review ''Physical Review'' is a peer-reviewed scientific journal established in 1893 by Edward Nichols. It publishes original research as well as scientific and literature reviews on all aspects of physics. It is published by the American Physical ...

'' four times (1927-1929, 1939-1941, 1954-1956, and 1961-1963). He was elected in 1923 a Fellow of the

American Physical Society The American Physical Society (APS) is a not-for-profit membership organization of professionals in physics and related disciplines, comprising nearly fifty divisions, sections, and other units. Its mission is the advancement and diffusion of k ...

. He was awarded the

Franklin Medal The Franklin Medal was a science award presented from 1915 until 1997 by the Franklin Institute located in Philadelphia, Pennsylvania, U.S. It was founded in 1914 by Samuel Insull. The Franklin Medal was the most prestigious of the various awar ...

in 1964. In 1967, he was awarded the National Medal of Science.National Science Foundation - The President's National Medal of Science
/ref>

References

External links

Annotated Bibliography for Gregory Breit from the Alsos Digital Library for Nuclear IssuesOral history interview with Gregory Breit on 8 December 1975, American Institute of Physics, Niels Bohr Library & Archives
by McAllister Hull
National Academy of Sciences Biographical Memoir
*
Gregory Breit Papers (MS 1465).
Manuscripts and Archives, Yale University Library. {{DEFAULTSORT:Breit, Gregory 1899 births 1981 deaths Jewish physicists 20th-century American physicists American nuclear physicists Johns Hopkins University alumni Manhattan Project people University at Buffalo faculty University of Wisconsin–Madison faculty Yale University faculty National Medal of Science laureates Jewish American scientists Fellows of the American Physical Society 20th-century American Jews Emigrants from the Russian Empire to the United States