Gregory Breit (, ; July 14, 1899 – September 13, 1981) was an 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 ...

born in

Mykolaiv Mykolaiv ( ), also known as Nikolaev ( ) is a List of cities in Ukraine, city and a hromada (municipality) in southern Ukraine. Mykolaiv is the Administrative centre, administrative center of Mykolaiv Raion (Raions of Ukraine, district) and Myk ...

Russian Empire The Russian Empire was an empire that spanned most of northern Eurasia from its establishment in November 1721 until the proclamation of the Russian Republic in September 1917. At its height in the late 19th century, it covered about , roughl ...

(now

Ukraine Ukraine is a country in Eastern Europe. It is the List of European countries by area, second-largest country in Europe after Russia, which Russia–Ukraine border, borders it to the east and northeast. Ukraine also borders Belarus to the nor ...

). He was a professor at

New York University New York University (NYU) is a private university, private research university in New York City, New York, United States. Chartered in 1831 by the New York State Legislature, NYU was founded in 1832 by Albert Gallatin as a Nondenominational ...

(1929–1934),

University of Wisconsin–Madison The University of Wisconsin–Madison (University of Wisconsin, Wisconsin, UW, UW–Madison, or simply Madison) is a public land-grant research university in Madison, Wisconsin, United States. It was founded in 1848 when Wisconsin achieved st ...

(1934–1947),

Yale University Yale University is a Private university, private Ivy League research university in New Haven, Connecticut, United States. Founded in 1701, Yale is the List of Colonial Colleges, third-oldest institution of higher education in the United Stat ...

(1947–1968), and

University at Buffalo The State University of New York at Buffalo (commonly referred to as UB, University at Buffalo, and sometimes SUNY Buffalo) is a public university, public research university in Buffalo, New York, Buffalo and Amherst, New York, United States. ...

(1968–1973). In 1921, he was

Paul Ehrenfest Paul Ehrenfest (; 18 January 1880 – 25 September 1933) was an Austrian Theoretical physics, theoretical physicist who made major contributions to statistical mechanics and its relation to quantum physics, quantum mechanics, including the theory ...

's assistant in

Leiden University Leiden University (abbreviated as ''LEI''; ) is a Public university, public research university in Leiden, Netherlands. Established in 1575 by William the Silent, William, Prince of Orange as a Protestantism, Protestant institution, it holds the d ...

Biography

He was born in the city of

in the family of the book publisher Alfred Schneider. After the death of his mother in 1911, his father left for the

United States of America The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 states and a federal capital district, Washington, D.C. The 48 contiguo ...

. Until 1915, Gregory studied at the Mykolaiv Oleksandrivska gymnasium. In 1915, he followed his father to USA. He studied at

Johns Hopkins University The Johns Hopkins University (often abbreviated as Johns Hopkins, Hopkins, or JHU) is a private university, private research university in Baltimore, Maryland, United States. Founded in 1876 based on the European research institution model, J ...

: in 1918 he obtained a Bachelor degree, in 1920 a Master degree, and in 1921 he earned a PhD in physics. In 1921-1922, he worked as a researcher at

. In 1922-1923, he was a research fellow at

Harvard University Harvard University is a Private university, private Ivy League research university in Cambridge, Massachusetts, United States. Founded in 1636 and named for its first benefactor, the History of the Puritans in North America, Puritan clergyma ...

. From 1923 to 1924, he was an assistant professor at the

University of Minnesota The University of Minnesota Twin Cities (historically known as University of Minnesota) is a public university, public Land-grant university, land-grant research university in the Minneapolis–Saint Paul, Twin Cities of Minneapolis and Saint ...

. In 1925, while at the Carnegie Institution of Washington, Breit joined with Merle Tuve 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 system that uses radio waves to determine the distance ('' ranging''), direction ( azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method used to detect and track ...

development. Together with

Eugene Wigner Eugene Paul Wigner (, ; November 17, 1902 – January 1, 1995) was a Hungarian-American theoretical physicist who also contributed to mathematical physics. He received the Nobel Prize in Physics in 1963 "for his contributions to the theory of th ...

, Breit gave a description of particle resonant states with the relativistic Breit–Wigner distribution 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 (jittery motion) in the solutions of the

Dirac equation In particle physics, the Dirac equation is a relativistic wave equation derived by British physicist Paul Dirac in 1928. In its free form, or including electromagnetic interactions, it describes all spin-1/2 massive particles, called "Dirac ...

. In 1934, together with John A. Wheeler, Breit described the Breit–Wheeler process. In 1939 he was elected to the

National Academy of Sciences The National Academy of Sciences (NAS) is a United States nonprofit, NGO, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the ...

. 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 (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

. During the early stages of the war, Breit was chosen by Arthur Compton to supervise the early design of the first atomic bomb during an early phase in what would later become the

Manhattan Project The Manhattan Project was a research and development program undertaken during World War II to produce the first nuclear weapons. It was led by the United States in collaboration with the United Kingdom and Canada. From 1942 to 1946, the ...

. 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 what became Project Y, the design and testing of the weapon. In 2014, experimentalists proposed a way to validate an idea by Breit and John A. Wheeler that matter formation could be achieved by interacting light particles (" Breit–Wheeler process"). Breit was associate editor of the '' Physical Review'' 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 ...

. He was awarded the Franklin Medal in 1964. In 1967, he was awarded the

National Medal of Science The National Medal of Science is an honor bestowed by the President of the United States to individuals in science and engineering who have made important contributions to the advancement of knowledge in the fields of behavioral science, behavior ...

.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
*

Archival collections

* Gregory Breit Papers (MS 1465). Manuscripts and Archives, Yale University Library
Alvin M. Saperstein student notes of lectures given by Gregory Breit, 1952-1954, Niels Bohr Library & Archives

George O. Zimmerman collection of lecture notes by Gregory Breit and Lars Onsager, circa 1960-1961, Niels Bohr Library & Archives

Gregory Breit selected papers [microform
(bulk 1950-1973), Niels Bohr Library & Archives">icroform">Gregory Breit selected papers [microform
(bulk 1950-1973), Niels Bohr Library & Archives {{DEFAULTSORT:Breit, Gregory 1899 births 1981 deaths Jewish American physicists Jewish Russian 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 Fellows of the American Physical Society 20th-century American Jews Emigrants from the Russian Empire to the United States Recipients of Franklin Medal