theoretical physicist Theoretical physics is a branch of physics that employs mathematical models and abstractions of physical objects and systems to rationalize, explain and predict natural phenomena. This is in contrast to experimental physics, which uses experimen ...

mathematical physics Mathematical physics refers to the development of mathematics, mathematical methods for application to problems in physics. The ''Journal of Mathematical Physics'' defines the field as "the application of mathematics to problems in physics and t ...

Nobel Prize in Physics ) , image = Nobel Prize.png , alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then " ...

atomic nucleus The atomic nucleus is the small, dense region consisting of protons and neutrons at the center of an atom, discovered in 1911 by Ernest Rutherford based on the 1909 Geiger–Marsden gold foil experiment. After the discovery of the neutron i ...

elementary particles In particle physics, an elementary particle or fundamental particle is a subatomic particle that is not composed of other particles. Particles currently thought to be elementary include electrons, the fundamental fermions (quarks, leptons, antiqu ...

Technical University of Berlin The Technical University of Berlin (official name both in English and german: link=no, Technische Universität Berlin, also known as TU Berlin and Berlin Institute of Technology) is a public research university located in Berlin, Germany. It was ...

Karl Weissenberg Karl Weissenberg (11 June 1893, Vienna – 6 April 1976, The Hague) was an Austrian physicist, notable for his contributions to rheology and crystallography.Richard Becker at the

Kaiser Wilhelm Institute The Kaiser Wilhelm Society for the Advancement of Science (German: ''Kaiser-Wilhelm-Gesellschaft zur Förderung der Wissenschaften'') was a German scientific institution established in the German Empire in 1911. Its functions were taken over by ...

in Berlin, and

David Hilbert David Hilbert (; ; 23 January 1862 – 14 February 1943) was a German mathematician, one of the most influential mathematicians of the 19th and early 20th centuries. Hilbert discovered and developed a broad range of fundamental ideas in many a ...

at the

University of Göttingen The University of Göttingen, officially the Georg August University of Göttingen, (german: Georg-August-Universität Göttingen, known informally as Georgia Augusta) is a public research university in the city of Göttingen, Germany. Founded ...

. Wigner and

Hermann Weyl Hermann Klaus Hugo Weyl, (; 9 November 1885 – 8 December 1955) was a German mathematician, theoretical physicist and philosopher. Although much of his working life was spent in Zürich, Switzerland, and then Princeton, New Jersey, he is assoc ...

were responsible for introducing

group theory In abstract algebra, group theory studies the algebraic structures known as group (mathematics), groups. The concept of a group is central to abstract algebra: other well-known algebraic structures, such as ring (mathematics), rings, field ...

into physics, particularly the theory of

symmetry in physics In physics, a symmetry of a physical system is a physical or mathematical feature of the system (observed or intrinsic) that is preserved or remains unchanged under some transformation. A family of particular transformations may be ''continuou ...

. Along the way he performed ground-breaking work in pure mathematics, in which he authored a number of

mathematical theorem In mathematics, a theorem is a statement that has been proved, or can be proved. The ''proof'' of a theorem is a logical argument that uses the inference rules of a deductive system to establish that the theorem is a logical consequence of the ...

s. In particular,

Wigner's theorem Wigner's theorem, proved by Eugene Wigner in 1931, is a cornerstone of the mathematical formulation of quantum mechanics. The theorem specifies how physical symmetries such as rotations, translations, and CPT are represented on the Hilbert spac ...

is a cornerstone in the

mathematical formulation of quantum mechanics The mathematical formulations of quantum mechanics are those mathematical formalisms that permit a rigorous description of quantum mechanics. This mathematical formalism uses mainly a part of functional analysis, especially Hilbert spaces, which ...

. He is also known for his research into the structure of the

atomic nucleus The atomic nucleus is the small, dense region consisting of protons and neutrons at the center of an atom, discovered in 1911 by Ernest Rutherford based on the 1909 Geiger–Marsden gold foil experiment. After the discovery of the neutron i ...

. In 1930,

Princeton University Princeton University is a private university, private research university in Princeton, New Jersey. Founded in 1746 in Elizabeth, New Jersey, Elizabeth as the College of New Jersey, Princeton is the List of Colonial Colleges, fourth-oldest ins ...

recruited Wigner, along with

John von Neumann John von Neumann (; hu, Neumann János Lajos, ; December 28, 1903 – February 8, 1957) was a Hungarian-American mathematician, physicist, computer scientist, engineer and polymath. He was regarded as having perhaps the widest cove ...

, and he moved to the United States, where he obtained citizenship in 1937. Wigner participated in a meeting with

Leo Szilard Leo Szilard (; hu, Szilárd Leó, pronounced ; born Leó Spitz; February 11, 1898 – May 30, 1964) was a Hungarian-German-American physicist and inventor. He conceived the nuclear chain reaction in 1933, patented the idea of a nuclear ...

and

Albert Einstein Albert Einstein ( ; ; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist, widely acknowledged to be one of the greatest and most influential physicists of all time. Einstein is best known for developing the theory ...

that resulted in the Einstein-Szilard letter, which prompted President

Franklin D. Roosevelt Franklin Delano Roosevelt (; ; January 30, 1882April 12, 1945), often referred to by his initials FDR, was an American politician and attorney who served as the 32nd president of the United States from 1933 until his death in 1945. As the ...

to initiate 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 ...

to develop

atomic bombs 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 ...

. Wigner was afraid that the

German nuclear weapon project The Uranverein ( en, "Uranium Club") or Uranprojekt ( en, "Uranium Project") was the name given to the project in Nazi Germany, Germany to research nuclear technology, including nuclear weapons and nuclear reactors, during World War II. It wen ...

would develop an atomic bomb first. During the Manhattan Project, he led a team whose task was to design

nuclear reactor A nuclear reactor is a device used to initiate and control a fission nuclear chain reaction or nuclear fusion reactions. Nuclear reactors are used at nuclear power plants for electricity generation and in nuclear marine propulsion. Heat from nu ...

s to convert

uranium Uranium is a chemical element with the symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Uranium is weak ...

into

weapons grade plutonium Weapons-grade nuclear material is any fissionable nuclear material that is pure enough to make a nuclear weapon or has properties that make it particularly suitable for nuclear weapons use. Plutonium and uranium in grades normally used in nucle ...

. At the time, reactors existed only on paper, and no reactor had yet gone critical. Wigner was disappointed that

DuPont DuPont de Nemours, Inc., commonly shortened to DuPont, is an American multinational chemical company first formed in 1802 by French-American chemist and industrialist Éleuthère Irénée du Pont de Nemours. The company played a major role in ...

was given responsibility for the detailed design of the reactors, not just their construction. He became Director of Research and Development at the Clinton Laboratory (now the

Oak Ridge National Laboratory Oak Ridge National Laboratory (ORNL) is a U.S. multiprogram science and technology national laboratory sponsored by the U.S. Department of Energy (DOE) and administered, managed, and operated by UT–Battelle as a federally funded research and ...

) in early 1946, but became frustrated with bureaucratic interference by the Atomic Energy Commission, and returned to Princeton. In the postwar period, he served on a number of government bodies, including the

National Bureau of Standards The National Institute of Standards and Technology (NIST) is an agency of the United States Department of Commerce whose mission is to promote American innovation and industrial competitiveness. NIST's activities are organized into physical sci ...

from 1947 to 1951, the mathematics panel of the

National Research Council National Research Council may refer to: * National Research Council (Canada), sponsoring research and development * National Research Council (Italy), scientific and technological research, Rome * National Research Council (United States), part of ...

from 1951 to 1954, the physics panel of the

National Science Foundation The National Science Foundation (NSF) is an independent agency of the United States government that supports fundamental research and education in all the non-medical fields of science and engineering. Its medical counterpart is the National I ...

, and the influential General Advisory Committee of the Atomic Energy Commission from 1952 to 1957 and again from 1959 to 1964. In later life, he became more philosophical, and published ''

The Unreasonable Effectiveness of Mathematics in the Natural Sciences "The Unreasonable Effectiveness of Mathematics in the Natural Sciences" is a 1960 article by the physicist Eugene Wigner. In the paper, Wigner observes that a physical theory's mathematical structure often points the way to further advances in that ...

'', his best-known work outside technical mathematics and physics.

Early life

Wigner Jenő Pál was born in

Budapest Budapest (, ; ) is the capital and most populous city of Hungary. It is the ninth-largest city in the European Union by population within city limits and the second-largest city on the Danube river; the city has an estimated population ...

,

Austria-Hungary Austria-Hungary, often referred to as the Austro-Hungarian Empire,, the Dual Monarchy, or Austria, was a constitutional monarchy and great power in Central Europe between 1867 and 1918. It was formed with the Austro-Hungarian Compromise of ...

on November 17, 1902, to middle class

Jew Jews ( he, יְהוּדִים, , ) or Jewish people are an ethnoreligious group and nation originating from the Israelites Israelite origins and kingdom: "The first act in the long drama of Jewish history is the age of the Israelites""Th ...

ish parents, Elisabeth Elsa Einhorn and Antal Anton Wigner, a leather tanner. He had an older sister, Berta, known as Biri, and a younger sister Margit, known as Manci, who later married British theoretical physicist

Paul Dirac Paul Adrien Maurice Dirac (; 8 August 1902 – 20 October 1984) was an English theoretical physicist who is regarded as one of the most significant physicists of the 20th century. He was the Lucasian Professor of Mathematics at the Univer ...

. He was home schooled by a professional teacher until the age of 9, when he started school at the third grade. During this period, Wigner developed an interest in mathematical problems. At the age of 11, Wigner contracted what his doctors believed to be

tuberculosis Tuberculosis (TB) is an infectious disease usually caused by '' Mycobacterium tuberculosis'' (MTB) bacteria. Tuberculosis generally affects the lungs, but it can also affect other parts of the body. Most infections show no symptoms, in ...

. His parents sent him to live for six weeks in a

sanatorium A sanatorium (from Latin '' sānāre'' 'to heal, make healthy'), also sanitarium or sanitorium, are antiquated names for specialised hospitals, for the treatment of specific diseases, related ailments and convalescence. Sanatoriums are often ...

in the Austrian mountains, before the doctors concluded that the diagnosis was mistaken. Wigner's family was Jewish, but not religiously observant, and his Bar Mitzvah was a secular one. From 1915 through 1919, he studied at the secondary grammar school called Fasori Evangélikus Gimnázium, the school his father had attended. Religious education was compulsory, and he attended classes in

Judaism Judaism ( he, ''Yahăḏūṯ'') is an Abrahamic, monotheistic, and ethnic religion comprising the collective religious, cultural, and legal tradition and civilization of the Jewish people. It has its roots as an organized religion in the ...

taught by a rabbi. A fellow student was

János von Neumann John von Neumann (; hu, Neumann János Lajos, ; December 28, 1903 – February 8, 1957) was a Hungarian-American mathematician, physicist, computer scientist, engineer and polymath. He was regarded as having perhaps the widest cover ...

, who was a year behind Wigner. They both benefited from the instruction of the noted mathematics teacher

László Rátz László Rátz (9 April 1863 in Sopron – 30 September 1930 in Budapest) was a Hungarian mathematics high school teacher best known for educating such people as John von Neumann and Nobel laureate Eugene Wigner. He was a legendary teac ...

. In 1919, to escape the

Béla Kun Béla Kun (born Béla Kohn; 20 February 1886 – 29 August 1938) was a Hungarian communist revolutionary and politician who governed the Hungarian Soviet Republic in 1919. After attending Franz Joseph University at Kolozsvár (today Cluj-Napoc ...

communist regime A communist state, also known as a Marxist–Leninist state, is a one-party state that is administered and governed by a communist party guided by Marxism–Leninism. Marxism–Leninism was the state ideology of the Soviet Union, the Cominte ...

, the Wigner family briefly fled to Austria, returning to

Hungary Hungary ( hu, Magyarország ) is a landlocked country in Central Europe. Spanning of the Carpathian Basin, it is bordered by Slovakia to the north, Ukraine to the northeast, Romania to the east and southeast, Serbia to the south, Croatia a ...

after Kun's downfall. Partly as a reaction to the prominence of Jews in the Kun regime, the family converted to

Lutheranism Lutheranism is one of the largest branches of Protestantism, identifying primarily with the theology of Martin Luther, the 16th-century German monk and Protestant Reformers, reformer whose efforts to reform the theology and practice of the Cathol ...

. Wigner explained later in his life that his family decision to convert to Lutheranism "was not at heart a religious decision but an anti-communist one". Regarding religion, Wigner was an

atheist Atheism, in the broadest sense, is an absence of belief in the existence of deities. Less broadly, atheism is a rejection of the belief that any deities exist. In an even narrower sense, atheism is specifically the position that there no ...

. After graduating from the secondary school in 1920, Wigner enrolled at the Budapest University of Technical Sciences, known as the ''Műegyetem''. He was not happy with the courses on offer, and in 1921 enrolled at the ''

Technische Hochschule A ''Technische Hochschule'' (, plural: ''Technische Hochschulen'', abbreviated ''TH'') is a type of university focusing on engineering sciences in Germany. Previously, it also existed in Austria, Switzerland, the Netherlands (), and Finland (, ). ...

Berlin'' (now

Technical University of Berlin The Technical University of Berlin (official name both in English and german: link=no, Technische Universität Berlin, also known as TU Berlin and Berlin Institute of Technology) is a public research university located in Berlin, Germany. It was ...

), where he studied

chemical engineering Chemical engineering is an engineering field which deals with the study of operation and design of chemical plants as well as methods of improving production. Chemical engineers develop economical commercial processes to convert raw materials int ...

. He also attended the Wednesday afternoon colloquia of the

German Physical Society The German Physical Society (German: , DPG) is the oldest organisation of physicists. The DPG's worldwide membership is cited as 60,547, as of 2019, making it the largest physics society in the world. It holds an annual conference () and multiple ...

. These colloquia featured leading researchers including

Max Planck Max Karl Ernst Ludwig Planck (, ; 23 April 1858 – 4 October 1947) was a German theoretical physicist whose discovery of energy quanta won him the Nobel Prize in Physics in 1918. Planck made many substantial contributions to theoretical p ...

,

Max von Laue Max Theodor Felix von Laue (; 9 October 1879 – 24 April 1960) was a German physicist who received the Nobel Prize in Physics in 1914 for his discovery of the diffraction of X-rays by crystals. In addition to his scientific endeavors with cont ...

,

Rudolf Ladenburg Rudolf Walter Ladenburg (June 6, 1882 in Kiel – April 6, 1952 in Princeton, New Jersey) was a German atomic physicist. He emigrated from Germany as early as 1932 and became a Brackett Research Professor at Princeton University. When the wave of G ...

,

Werner Heisenberg Werner Karl Heisenberg () (5 December 1901 – 1 February 1976) was a German theoretical physicist and one of the main pioneers of the theory of quantum mechanics. He published his work in 1925 in a breakthrough paper. In the subsequent series ...

,

Walther Nernst Walther Hermann Nernst (; 25 June 1864 – 18 November 1941) was a German chemist known for his work in thermodynamics, physical chemistry, electrochemistry, and solid state physics. His formulation of the Nernst heat theorem helped pave the wa ...

,

Wolfgang Pauli Wolfgang Ernst Pauli (; ; 25 April 1900 – 15 December 1958) was an Austrian theoretical physicist and one of the pioneers of quantum physics. In 1945, after having been nominated by Albert Einstein, Pauli received the Nobel Prize in Physics fo ...

, and

Albert Einstein Albert Einstein ( ; ; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist, widely acknowledged to be one of the greatest and most influential physicists of all time. Einstein is best known for developing the theory ...

. Wigner also met the physicist

Leó Szilárd Leo Szilard (; hu, Szilárd Leó, pronounced ; born Leó Spitz; February 11, 1898 – May 30, 1964) was a Hungarian-German-American physicist and inventor. He conceived the nuclear chain reaction in 1933, patented the idea of a nuclear ...

, who at once became Wigner's closest friend. A third experience in Berlin was formative. Wigner worked at the

Kaiser Wilhelm Institute for Physical Chemistry and Electrochemistry The Fritz Haber Institute of the Max Planck Society (FHI) is a science research institute located at the heart of the academic district of Dahlem (Berlin), Dahlem, in Berlin, Germany. The original Kaiser Wilhelm Institute for Physical Chemistry ...

(now the

Fritz Haber Institute The Fritz Haber Institute of the Max Planck Society (FHI) is a science research institute located at the heart of the academic district of Dahlem, in Berlin, Germany. The original Kaiser Wilhelm Institute for Physical Chemistry and Electrochem ...

), and there he met

Michael Polanyi Michael Polanyi (; hu, Polányi Mihály; 11 March 1891 – 22 February 1976) was a Hungarian-British polymath, who made important theoretical contributions to physical chemistry, economics, and philosophy. He argued that positivism supplies ...

, who became, after

László Rátz László Rátz (9 April 1863 in Sopron – 30 September 1930 in Budapest) was a Hungarian mathematics high school teacher best known for educating such people as John von Neumann and Nobel laureate Eugene Wigner. He was a legendary teac ...

, Wigner's greatest teacher. Polanyi supervised Wigner's

DSc DSC may refer to: Academia * Doctor of Science (D.Sc.) * District Selection Committee, an entrance exam in India * Doctor of Surgical Chiropody, superseded in the 1960s by Doctor of Podiatric Medicine Educational institutions * Dalton State Col ...

thesis, ''Bildung und Zerfall von Molekülen'' ("Formation and Decay of Molecules").

Middle years

Wigner returned to Budapest, where he went to work at his father's tannery, but in 1926, he accepted an offer from

Karl Weissenberg Karl Weissenberg (11 June 1893, Vienna – 6 April 1976, The Hague) was an Austrian physicist, notable for his contributions to rheology and crystallography.Kaiser Wilhelm Institute The Kaiser Wilhelm Society for the Advancement of Science (German: ''Kaiser-Wilhelm-Gesellschaft zur Förderung der Wissenschaften'') was a German scientific institution established in the German Empire in 1911. Its functions were taken over by ...

in Berlin. Weissenberg wanted someone to assist him with his work on

x-ray An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nb ...

crystallography Crystallography is the experimental science of determining the arrangement of atoms in crystalline solids. Crystallography is a fundamental subject in the fields of materials science and solid-state physics (condensed matter physics). The wor ...

, and Polanyi had recommended Wigner. After six months as Weissenberg's assistant, Wigner went to work for Richard Becker for two semesters. Wigner explored

quantum mechanics Quantum mechanics is a fundamental theory in physics that provides a description of the physical properties of nature at the scale of atoms and subatomic particles. It is the foundation of all quantum physics including quantum chemistry, ...

, studying the work of

Erwin Schrödinger Erwin Rudolf Josef Alexander Schrödinger (, ; ; 12 August 1887 – 4 January 1961), sometimes written as or , was a Nobel Prize-winning Austrian physicist with Irish citizenship who developed a number of fundamental results in quantum theory ...

. He also delved into the

group theory In abstract algebra, group theory studies the algebraic structures known as group (mathematics), groups. The concept of a group is central to abstract algebra: other well-known algebraic structures, such as ring (mathematics), rings, field ...

of Ferdinand Frobenius and

Eduard Ritter von Weber Eduard Ritter von Weber (May 12, 1870 in Munich – June 20, 1934 in Würzburg) was a German mathematician. Von Weber attended the and afterward from 1888-1894 pursued studies in mathematics in Munich, Göttingen, and Paris. In 1893 he was ...

. Wigner received a request from

Arnold Sommerfeld Arnold Johannes Wilhelm Sommerfeld, (; 5 December 1868 – 26 April 1951) was a German theoretical physicist who pioneered developments in atomic and quantum physics, and also educated and mentored many students for the new era of theoretica ...

to work at the

University of Göttingen The University of Göttingen, officially the Georg August University of Göttingen, (german: Georg-August-Universität Göttingen, known informally as Georgia Augusta) is a public research university in the city of Göttingen, Germany. Founded ...

as an assistant to the great mathematician

David Hilbert David Hilbert (; ; 23 January 1862 – 14 February 1943) was a German mathematician, one of the most influential mathematicians of the 19th and early 20th centuries. Hilbert discovered and developed a broad range of fundamental ideas in many a ...

. This proved a disappointment, as the aged Hilbert's abilities were failing, and his interests had shifted to logic. Wigner nonetheless studied independently. He laid the foundation for the theory of symmetries in quantum mechanics and in 1927 introduced what is now known as the

Wigner D-matrix The Wigner D-matrix is a unitary matrix in an irreducible representation of the groups SU(2) and SO(3). It was introduced in 1927 by Eugene Wigner, and plays a fundamental role in the quantum mechanical theory of angular momentum. The complex conjug ...

. Wigner and

Hermann Weyl Hermann Klaus Hugo Weyl, (; 9 November 1885 – 8 December 1955) was a German mathematician, theoretical physicist and philosopher. Although much of his working life was spent in Zürich, Switzerland, and then Princeton, New Jersey, he is assoc ...

were responsible for introducing group theory into quantum mechanics. The latter had written a standard text, ''Group Theory and Quantum Mechanics'' (1928), but it was not easy to understand, especially for younger physicists. Wigner's ''Group Theory and Its Application to the Quantum Mechanics of Atomic Spectra'' (1931) made group theory accessible to a wider audience. Jucys diagram for Wigner 6-j symbol

In these works, Wigner laid the foundation for the theory of

symmetries Symmetry (from grc, συμμετρία "agreement in dimensions, due proportion, arrangement") in everyday language refers to a sense of harmonious and beautiful proportion and balance. In mathematics, "symmetry" has a more precise definiti ...

in

quantum mechanics Quantum mechanics is a fundamental theory in physics that provides a description of the physical properties of nature at the scale of atoms and subatomic particles. It is the foundation of all quantum physics including quantum chemistry, ...

.

Wigner's theorem Wigner's theorem, proved by Eugene Wigner in 1931, is a cornerstone of the mathematical formulation of quantum mechanics. The theorem specifies how physical symmetries such as rotations, translations, and CPT are represented on the Hilbert spac ...

proved by Wigner in 1931, is a cornerstone of the

mathematical formulation of quantum mechanics The mathematical formulations of quantum mechanics are those mathematical formalisms that permit a rigorous description of quantum mechanics. This mathematical formalism uses mainly a part of functional analysis, especially Hilbert spaces, which ...

. The theorem specifies how physical

symmetries Symmetry (from grc, συμμετρία "agreement in dimensions, due proportion, arrangement") in everyday language refers to a sense of harmonious and beautiful proportion and balance. In mathematics, "symmetry" has a more precise definiti ...

such as rotations, translations, and

CPT symmetry Charge, parity, and time reversal symmetry is a fundamental symmetry of physical laws under the simultaneous transformations of charge conjugation (C), parity transformation (P), and time reversal (T). CPT is the only combination of C, P, and T ...

are represented on the

Hilbert space In mathematics, Hilbert spaces (named after David Hilbert) allow generalizing the methods of linear algebra and calculus from (finite-dimensional) Euclidean vector spaces to spaces that may be infinite-dimensional. Hilbert spaces arise natural ...

of states. According to the theorem, any symmetry transformation is represented by a linear and unitary or antilinear and antiunitary transformation of Hilbert space. The representation of a symmetry group on a Hilbert space is either an ordinary

representation Representation may refer to: Law and politics *Representation (politics), political activities undertaken by elected representatives, as well as other theories ** Representative democracy, type of democracy in which elected officials represent a ...

or a

projective representation In the field of representation theory in mathematics, a projective representation of a group ''G'' on a vector space ''V'' over a field ''F'' is a group homomorphism from ''G'' to the projective linear group \mathrm(V) = \mathrm(V) / F^*, where GL(' ...

. In the late 1930s, Wigner extended his research into atomic nuclei. By 1929, his papers were drawing notice in the world of physics. In 1930,

Princeton University Princeton University is a private university, private research university in Princeton, New Jersey. Founded in 1746 in Elizabeth, New Jersey, Elizabeth as the College of New Jersey, Princeton is the List of Colonial Colleges, fourth-oldest ins ...

recruited Wigner for a one-year lectureship, at 7 times the salary that he had been drawing in Europe. Princeton recruited von Neumann at the same time. Jenő Pál Wigner and János von Neumann had collaborated on three papers together in 1928 and two in 1929. They anglicized their first names to "Eugene" and "John", respectively. When their year was up, Princeton offered a five-year contract as visiting professors for half the year. The Technische Hochschule responded with a teaching assignment for the other half of the year. This was very timely, since the

Nazi Nazism ( ; german: Nazismus), the common name in English for National Socialism (german: Nationalsozialismus, ), is the far-right totalitarian political ideology and practices associated with Adolf Hitler and the Nazi Party (NSDAP) in ...

s soon rose to power in Germany. At Princeton in 1934, Wigner introduced his sister Margit "Manci" Wigner to the physicist

Paul Dirac Paul Adrien Maurice Dirac (; 8 August 1902 – 20 October 1984) was an English theoretical physicist who is regarded as one of the most significant physicists of the 20th century. He was the Lucasian Professor of Mathematics at the Univer ...

, with whom she remarried. Princeton did not rehire Wigner when his contract ran out in 1936. Through

Gregory Breit Gregory Breit (russian: Григорий Альфредович Брейт-Шнайдер, ''Grigory Alfredovich Breit-Shneider''; July 14, 1899, Mykolaiv, Kherson Governorate – September 13, 1981, Salem, Oregon) was a Russian-born Jewish Am ...

, Wigner found new employment at the

University of Wisconsin 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 States, t ...

. There, he met his first wife, Amelia Frank, who was a physics student there. However, she died unexpectedly in 1937, leaving Wigner distraught. He therefore accepted a 1938 offer from Princeton to return there. Wigner became a

naturalized citizen Naturalization (or naturalisation) is the legal act or process by which a non-citizen of a country may acquire citizenship or nationality of that country. It may be done automatically by a statute, i.e., without any effort on the part of the in ...

of the United States on January 8, 1937, and he brought his parents to the United States.

Manhattan Project

Eugene Wigner receiving Medal for Merit cph

Although he was a professed political amateur, on August 2, 1939, he participated in a meeting with

Leó Szilárd Leo Szilard (; hu, Szilárd Leó, pronounced ; born Leó Spitz; February 11, 1898 – May 30, 1964) was a Hungarian-German-American physicist and inventor. He conceived the nuclear chain reaction in 1933, patented the idea of a nuclear ...

and

Albert Einstein Albert Einstein ( ; ; 14 March 1879 – 18 April 1955) was a German-born theoretical physicist, widely acknowledged to be one of the greatest and most influential physicists of all time. Einstein is best known for developing the theory ...

that resulted in the Einstein–Szilárd letter, which prompted President

Franklin D. Roosevelt Franklin Delano Roosevelt (; ; January 30, 1882April 12, 1945), often referred to by his initials FDR, was an American politician and attorney who served as the 32nd president of the United States from 1933 until his death in 1945. As the ...

to initiate 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 ...

to develop

atomic bombs 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 ...

. Wigner was afraid that the

German nuclear weapon project The Uranverein ( en, "Uranium Club") or Uranprojekt ( en, "Uranium Project") was the name given to the project in Nazi Germany, Germany to research nuclear technology, including nuclear weapons and nuclear reactors, during World War II. It wen ...

would develop an atomic bomb first, and even refused to have his fingerprints taken because they could be used to track him down if Germany won. "Thoughts of being murdered," he later recalled, "focus your mind wonderfully." On June 4, 1941, Wigner married his second wife, Mary Annette Wheeler, a professor of physics at

Vassar College Vassar College ( ) is a private liberal arts college in Poughkeepsie, New York, United States. Founded in 1861 by Matthew Vassar, it was the second degree-granting institution of higher education for women in the United States, closely follo ...

, who had completed her Ph.D. at

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 wo ...

in 1932. After the war she taught physics on the faculty of

Rutgers University Rutgers University (; RU), officially Rutgers, The State University of New Jersey, is a Public university, public land-grant research university consisting of four campuses in New Jersey. Chartered in 1766, Rutgers was originally called Queen's ...

's

Douglass College Douglass Residential College, is an undergraduate, non degree granting higher education program of Rutgers University-New Brunswick for women. It succeeded the liberal arts degree-granting Douglass College after it was merged with the other unde ...

in New Jersey until her retirement in 1964. They remained married until her death in November 1977. They had two children, David Wigner and Martha Wigner Upton. During the Manhattan Project, Wigner led a team that included

J. Ernest Wilkins Jr. Jesse Ernest Wilkins Jr. (November 27, 1923 – May 1, 2011) was an African American nuclear scientist, mechanical engineer and mathematician. A child prodigy, he attended the University of Chicago at the age of 13, becoming its youngest ever s ...

,

Alvin M. Weinberg Alvin Martin Weinberg (; April 20, 1915 – October 18, 2006) was an American nuclear physicist who was the administrator at Oak Ridge National Laboratory (ORNL) during and after the Manhattan Project. He came to Oak Ridge, Tennessee, in 1945 ...

,

Katharine Way Katharine "Kay" Way (February 20, 1902 – December 9, 1995) was an American physicist best known for her work on the Nuclear Data Project. During World War II, she worked for the Manhattan Project at the Metallurgical Laboratory in Chicago. She ...

, Gale Young and

Edward Creutz Edward Creutz (January 23, 1913 – June 27, 2009) was an American physicist who worked on the Manhattan Project at the Metallurgical Laboratory and the Los Alamos Laboratory during World War II. After the war he became a professor of p ...

. The group's task was to design the production nuclear reactors that would convert uranium into weapons grade plutonium. At the time, reactors existed only on paper, and no reactor had yet gone critical. In July 1942, Wigner chose a conservative 100 MW design, with a

graphite Graphite () is a crystalline form of the element carbon. It consists of stacked layers of graphene. Graphite occurs naturally and is the most stable form of carbon under standard conditions. Synthetic and natural graphite are consumed on large ...

neutron moderator In nuclear engineering, a neutron moderator is a medium that reduces the speed of fast neutrons, ideally without capturing any, leaving them as thermal neutrons with only minimal (thermal) kinetic energy. These thermal neutrons are immensely mo ...

and water cooling. Wigner was present at a converted rackets court under the stands at the

University of Chicago The University of Chicago (UChicago, Chicago, U of C, or UChi) is a private research university in Chicago, Illinois. Its main campus is located in Chicago's Hyde Park neighborhood. The University of Chicago is consistently ranked among the b ...

's abandoned

Stagg Field Amos Alonzo Stagg Field is the name of two successive football fields for the University of Chicago. Beyond sports, the first Stagg Field (1893–1957) is remembered for its role in a landmark scientific achievement of Enrico Fermi and the Metall ...

on December 2, 1942, when the world's first atomic reactor, Chicago Pile One (CP-1) achieved a controlled

nuclear chain reaction In nuclear physics, a nuclear chain reaction occurs when one single nuclear reaction causes an average of one or more subsequent nuclear reactions, thus leading to the possibility of a self-propagating series of these reactions. The specific nu ...

.

Wigner was disappointed that

DuPont DuPont de Nemours, Inc., commonly shortened to DuPont, is an American multinational chemical company first formed in 1802 by French-American chemist and industrialist Éleuthère Irénée du Pont de Nemours. The company played a major role in ...

was given responsibility for the detailed design of the reactors, not just their construction. He threatened to resign in February 1943, but was talked out of it by the head of the

Metallurgical Laboratory The Metallurgical Laboratory (or Met Lab) was a scientific laboratory at the University of Chicago that was established in February 1942 to study and use the newly discovered chemical element plutonium. It researched plutonium's chemistry and m ...

,

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 ...

, who sent him on vacation instead. As it turned out, a design decision by DuPont to give the reactor additional load tubes for more uranium saved the project when

neutron poison In applications such as nuclear reactors, a neutron poison (also called a neutron absorber or a nuclear poison) is a substance with a large neutron absorption cross-section. In such applications, absorbing neutrons is normally an undesirable eff ...

ing became a problem. Without the additional tubes, the reactor could have been run at 35% power until the boron impurities in the graphite were burned up and enough plutonium produced to run the reactor at full power; but this would have set the project back a year. During the 1950s, he would even work for DuPont on the

Savannah River Site The Savannah River Site (SRS) is a U.S. Department of Energy (DOE) reservation in the United States in the state of South Carolina, located on land in Aiken, Allendale, and Barnwell counties adjacent to the Savannah River, southeast of August ...

. Wigner did not regret working on the Manhattan Project, and sometimes wished the atomic bomb had been ready a year earlier. An important discovery Wigner made during the project was the

Wigner effect The Wigner effect (named for its discoverer, Eugene Wigner), also known as the discomposition effect or Wigner's disease, is the displacement of atoms in a solid caused by neutron radiation. Any solid can display the Wigner effect. The effect is ...

. This is a swelling of the graphite moderator caused by the displacement of atoms by

neutron radiation Neutron radiation is a form of ionizing radiation that presents as free neutrons. Typical phenomena are nuclear fission or nuclear fusion causing the release of free neutrons, which then Neutron capture, react with Atomic nucleus, nuclei of other ...

. The Wigner effect was a serious problem for the reactors at the

Hanford Site The Hanford Site is a decommissioned nuclear production complex operated by the United States federal government on the Columbia River in Benton County in the U.S. state of Washington. The site has been known by many names, including SiteW a ...

in the immediate post-war period, and resulted in production cutbacks and a reactor being shut down entirely. It was eventually discovered that it could be overcome by controlled heating and annealing. Through Manhattan project funding, Wigner and Leonard Eisenbud also developed an important general approach to nuclear reactions, the Wigner–Eisenbud R-matrix theory, which was published in 1947.

Later years

Wigner accepted a position as the Director of Research and Development at the Clinton Laboratory (now the

Oak Ridge National Laboratory Oak Ridge National Laboratory (ORNL) is a U.S. multiprogram science and technology national laboratory sponsored by the U.S. Department of Energy (DOE) and administered, managed, and operated by UT–Battelle as a federally funded research and ...

) in

Oak Ridge, Tennessee Oak Ridge is a city in Anderson and Roane counties in the eastern part of the U.S. state of Tennessee, about west of downtown Knoxville. Oak Ridge's population was 31,402 at the 2020 census. It is part of the Knoxville Metropolitan Area. Oak ...

in early 1946. Because he did not want to be involved in administrative duties, he became co-director of the laboratory, with James Lum handling the administrative chores as executive director. When the newly created Atomic Energy Commission (AEC) took charge of the laboratory's operations at the start of 1947, Wigner feared that many of the technical decisions would be made in Washington. He also saw the Army's continuation of wartime security policies at the laboratory as a "meddlesome oversight", interfering with research. One such incident occurred in March 1947, when the AEC discovered that Wigner's scientists were conducting experiments with a

critical mass In nuclear engineering, a critical mass is the smallest amount of fissile material needed for a sustained nuclear chain reaction. The critical mass of a fissionable material depends upon its nuclear properties (specifically, its nuclear fissi ...

of

uranium-235 Uranium-235 (235U or U-235) is an isotope of uranium making up about 0.72% of natural uranium. Unlike the predominant isotope uranium-238, it is fissile, i.e., it can sustain a nuclear chain reaction. It is the only fissile isotope that exis ...

when the Director of the Manhattan Project,

Major General Major general (abbreviated MG, maj. gen. and similar) is a military rank used in many countries. It is derived from the older rank of sergeant major general. The disappearance of the "sergeant" in the title explains the apparent confusion of a ...

Leslie R. Groves, Jr. Lieutenant General Leslie Richard Groves Jr. (17 August 1896 – 13 July 1970) was a United States Army Corps of Engineers officer who oversaw the construction of the Pentagon and directed the Manhattan Project, a top secret research project ...

, had forbidden such experiments in August 1946 after the death of

Louis Slotin Louis Alexander Slotin (1 December 1910 – 30 May 1946) was a Canadian physicist and chemist who took part in the Manhattan Project. Born and raised in the North End of Winnipeg, Manitoba, Slotin earned both his Bachelor of Science and M ...

at the

Los Alamos Laboratory The Los Alamos Laboratory, also known as Project Y, was a secret laboratory established by the Manhattan Project and operated by the University of California during World War II. Its mission was to design and build the first atomic bombs. Ro ...

. Wigner argued that Groves's order had been superseded, but was forced to terminate the experiments, which were completely different from the one that killed Slotin. Feeling unsuited to a managerial role in such an environment, he left Oak Ridge in 1947 and returned to Princeton University, although he maintained a consulting role with the facility for many years. In the postwar period, he served on a number of government bodies, including the

National Bureau of Standards The National Institute of Standards and Technology (NIST) is an agency of the United States Department of Commerce whose mission is to promote American innovation and industrial competitiveness. NIST's activities are organized into physical sci ...

from 1947 to 1951, the mathematics panel of the

National Research Council National Research Council may refer to: * National Research Council (Canada), sponsoring research and development * National Research Council (Italy), scientific and technological research, Rome * National Research Council (United States), part of ...

from 1951 to 1954, the physics panel of the

National Science Foundation The National Science Foundation (NSF) is an independent agency of the United States government that supports fundamental research and education in all the non-medical fields of science and engineering. Its medical counterpart is the National I ...

, and the influential General Advisory Committee of the Atomic Energy Commission from 1952 to 1957 and again from 1959 to 1964. He also contributed to

civil defense Civil defense ( en, region=gb, civil defence) or civil protection is an effort to protect the citizens of a state (generally non-combatants) from man-made and natural disasters. It uses the principles of emergency operations: prevention, miti ...

. Near the end of his life, Wigner's thoughts turned more philosophical. In 1960, he published a now classic article on the philosophy of mathematics and of physics, which has become his best-known work outside technical mathematics and physics, "

The Unreasonable Effectiveness of Mathematics in the Natural Sciences "The Unreasonable Effectiveness of Mathematics in the Natural Sciences" is a 1960 article by the physicist Eugene Wigner. In the paper, Wigner observes that a physical theory's mathematical structure often points the way to further advances in that ...

". He argued that biology and cognition could be the origin of physical concepts, as we humans perceive them, and that the happy coincidence that mathematics and physics were so well matched, seemed to be "unreasonable" and hard to explain. His original paper has provoked and inspired many responses across a wide range of disciplines. These included

Richard Hamming Richard Wesley Hamming (February 11, 1915 – January 7, 1998) was an American mathematician whose work had many implications for computer engineering and telecommunications. His contributions include the Hamming code (which makes use of a Ha ...

in Computer Science,

Arthur Lesk Arthur Mallay Lesk, is a protein science researcher, who is a professor of biochemistry and molecular biology at the Pennsylvania State University in University Park. Education Lesk received a bachelor's degree, magna cum laude, from Harvard Uni ...

in Molecular Biology,

Peter Norvig Peter Norvig (born December 14, 1956) is an American computer scientist and Distinguished Education Fellow at the Stanford Institute for Human-Centered AI. He previously served as a director of research and search quality at Google. Norvig is t ...

in data mining,

Max Tegmark Max Erik Tegmark (born 5 May 1967) is a Swedish-American physicist, cosmologist and machine learning researcher. He is a professor at the Massachusetts Institute of Technology and the president of the Future of Life Institute. He is also a scienti ...

in Physics,

Ivor Grattan-Guinness Ivor Owen Grattan-Guinness (23 June 1941 – 12 December 2014) was a historian of mathematics and logic. Life Grattan-Guinness was born in Bakewell, England; his father was a mathematics teacher and educational administrator. He gained his bac ...

in Mathematics, and

Vela Velupillai Kumaraswamy (Vela) Velupillai (born 1947) is an academic economist and a ''Senior Visiting Professor'' at the Madras School of Economics and was, formerly, (''Distinguished'') ''Professor of Economics'' at the New School for Social Research in Ne ...

in Economics. Turning to philosophical questions about the theory of quantum mechanics, Wigner developed a thought experiment (later called Wigner's Friend paradox) to illustrate his belief that consciousness is foundational to the quantum mechanical measurement process. He thereby followed an ontological approach that sets human's consciousness at the center: "All that quantum mechanics purports to provide are probability connections between subsequent impressions (also called 'apperceptions') of the consciousness". Measurements are understood as the interactions which create the impressions in our consciousness (and as a result modify the wave function of the "measured" physical system), an idea which has been called the "

consciousness causes collapse Consciousness, at its simplest, is sentience and awareness of internal and external existence. However, the lack of definitions has led to millennia of analyses, explanations and debates by philosophers, theologians, linguisticians, and scient ...

" interpretation. Interestingly,

Hugh Everett III Hugh Everett III (; November 11, 1930 – July 19, 1982) was an American physicist who first proposed the many-worlds interpretation (MWI) of quantum physics, which he termed his "relative state" formulation. In contrast to the then-dominant Cope ...

(a student of Wigner) discussed Wigner's thought experiment in the introductory part of his 1957 dissertation as an "amusing, but ''extremely hypothetical'' drama". In an early draft of Everett's work, one also finds a drawing of the Wigner's Friend situation, which must be seen as the first evidence on paper of the thought experiment that was later assigned to be Wigner's. This suggests that Everett must at least have discussed the problem together with Wigner. In November 1963, Wigner called for the allocation of 10% of the national defense budget to be spent on nuclear blast shelters and survival resources, arguing that such an expenditure would be less costly than disarmament. Wigner considered a recent

Woods Hole Woods Hole is a census-designated place in the town of Falmouth in Barnstable County, Massachusetts, United States. It lies at the extreme southwest corner of Cape Cod, near Martha's Vineyard and the Elizabeth Islands. The population was 781 at ...

study's conclusion that a nuclear strike would kill 20% of Americans to be a very modest projection and that the country could recover from such an attack more quickly than Germany had recovered from the devastation of World War II. Wigner was awarded the

Nobel Prize in Physics ) , image = Nobel Prize.png , alt = A golden medallion with an embossed image of a bearded man facing left in profile. To the left of the man is the text "ALFR•" then "NOBEL", and on the right, the text (smaller) "NAT•" then " ...

in 1963 "for his contributions to the theory of the

atomic nucleus The atomic nucleus is the small, dense region consisting of protons and neutrons at the center of an atom, discovered in 1911 by Ernest Rutherford based on the 1909 Geiger–Marsden gold foil experiment. After the discovery of the neutron i ...

and the

elementary particles In particle physics, an elementary particle or fundamental particle is a subatomic particle that is not composed of other particles. Particles currently thought to be elementary include electrons, the fundamental fermions (quarks, leptons, antiqu ...

, particularly through the discovery and application of fundamental symmetry principles". The prize was shared that year, with the other half of the award divided between

Maria Goeppert-Mayer Maria Goeppert Mayer (; June 28, 1906 – February 20, 1972) was a German-born American theoretical physicist, and Nobel laureate in Physics for proposing the nuclear shell model of the atomic nucleus The atomic nucleus is the small, dense ...

and

J. Hans D. Jensen Johannes Hans Daniel Jensen (; 25 June 1907 – 11 February 1973) was a German nuclear physicist. During World War II, he worked on the German nuclear energy project, known as the Uranium Club, where he contributed to the separation of uranium is ...

. Wigner professed that he had never considered the possibility that this might occur, and added: "I never expected to get my name in the newspapers without doing something wicked." He also won 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 Samuel Insull (November 11, 1859 – July 16, 1938) was a Bri ...

in 1950, the

Enrico Fermi Enrico Fermi (; 29 September 1901 – 28 November 1954) was an Italian (later naturalized American) physicist and the creator of the world's first nuclear reactor, the Chicago Pile-1. He has been called the "architect of the nuclear age" and ...

award in 1958, the

Atoms for Peace Award The Atoms for Peace Award was established in 1955 through a grant of $1,000,000 by the Ford Motor Company Fund. An independent nonprofit corporation was set up to administer the award for the development or application of peaceful nuclear technol ...

in 1959, the

Max Planck Medal The Max Planck medal is the highest award of the German Physical Society , the world's largest organization of physicists, for extraordinary achievements in theoretical physics. The prize has been awarded annually since 1929, with few exceptions, ...

in 1961, 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 and social scienc ...

in 1969, the

Albert Einstein Award The Albert Einstein Award (sometimes mistakenly called the ''Albert Einstein Medal'' because it was accompanied with a gold medal) was an award in theoretical physics, given periodically from 1951 to 1979, that was established to recognize high ac ...

in 1972, the Golden Plate Award of the

American Academy of Achievement The American Academy of Achievement, colloquially known as the Academy of Achievement, is a non-profit educational organization that recognizes some of the highest achieving individuals in diverse fields and gives them the opportunity to meet o ...

in 1974, and the eponymous

Wigner Medal The International Colloquium on Group Theoretical Methods in Physics is an academic conference devoted to applications of group theory to physics. It was founded in 1972 by Henri Bacry and Aloysio Janner. It hosts a colloquium every two years. Th ...

in 1978. In 1968 he gave the

Josiah Willard Gibbs Josiah Willard Gibbs (; February 11, 1839 – April 28, 1903) was an American scientist who made significant theoretical contributions to physics, chemistry, and mathematics. His work on the applications of thermodynamics was instrumental in t ...

lecture. Mary died in November 1977. In 1979, Wigner married his third wife, Eileen Clare-Patton (Pat) Hamilton, the widow of physicist Donald Ross Hamilton, the Dean of the Graduate School at Princeton University, who had died in 1972. In 1992, at the age of 90, he published his memoirs, ''The Recollections of Eugene P. Wigner'' with

Andrew Szanton Andrew Szanton (born in Washington, D.C. in 1963) is an American collaborative memoirist. During his career he has worked with a wide range of subjects including civil rights pioneer Charles Evers, Nobel Prize winning physicist Eugene Wigner, form ...

. In it, Wigner said: "The full meaning of life, the collective meaning of all human desires, is fundamentally a mystery beyond our grasp. As a young man, I chafed at this state of affairs. But by now I have made peace with it. I even feel a certain honor to be associated with such a mystery." In his collection of essays 'Philosophical Reflections and Syntheses' (1995), he commented: "It was not possible to formulate the laws of quantum mechanics in a fully consistent way without reference to consciousness." Wigner died of

pneumonia Pneumonia is an inflammatory condition of the lung primarily affecting the small air sacs known as alveoli. Symptoms typically include some combination of productive or dry cough, chest pain, fever, and difficulty breathing. The severity ...

at the University Medical Center in

Princeton, New Jersey Princeton is a municipality with a borough form of government in Mercer County, in the U.S. state of New Jersey. It was established on January 1, 2013, through the consolidation of the Borough of Princeton and Princeton Township, both of whi ...

on 1 January 1995. He was survived by his wife Eileen (died 2010) and children Erika, David and Martha, and his sisters Bertha and Margit.

Publications

* 1958 (with

Alvin M. Weinberg Alvin Martin Weinberg (; April 20, 1915 – October 18, 2006) was an American nuclear physicist who was the administrator at Oak Ridge National Laboratory (ORNL) during and after the Manhattan Project. He came to Oak Ridge, Tennessee, in 1945 ...

). ''Physical Theory of Neutron Chain Reactors'' University of Chicago Press. * 1959. ''Group Theory and its Application to the Quantum Mechanics of Atomic Spectra''. New York: Academic Press. Translation by J. J. Griffin of 1931, ''Gruppentheorie und ihre Anwendungen auf die Quantenmechanik der Atomspektren'', Vieweg Verlag, Braunschweig. * 1970 ''Symmetries and Reflections: Scientific Essays''. Indiana University Press, Bloomington * 1992 (as told to

Andrew Szanton Andrew Szanton (born in Washington, D.C. in 1963) is an American collaborative memoirist. During his career he has worked with a wide range of subjects including civil rights pioneer Charles Evers, Nobel Prize winning physicist Eugene Wigner, form ...

). ''The Recollections of Eugene P. Wigner''. Plenum. * 1995 (with

Jagdish Mehra Jagdish Mehra (April 8, 1931 – September 14, 2008) was an Indian-American historian of science. Academic career Mehra was educated at Allahabad University, the Max Planck Institut für Physik and the University of California at Los Angeles a ...

and

Arthur Wightman Arthur Strong Wightman (March 30, 1922 – January 13, 2013) was an American mathematical physicist. He was one of the founders of the axiomatic approach to quantum field theory, and originated the set of Wightman axioms. With his rigorous treatm ...

, eds.). ''Philosophical Reflections and Syntheses''. Springer, Berlin

Selected contributions

;Theoretical physics *

Bargmann–Wigner equations :''This article uses the Einstein summation convention for tensor/spinor indices, and uses hats for quantum operators. In relativistic quantum mechanics and quantum field theory, the Bargmann–Wigner equations describe free particles with non ...

*

Jordan–Wigner transformation The Jordan–Wigner transformation is a transformation that maps spin operators onto fermionic creation and annihilation operators. It was proposed by Pascual Jordan and Eugene Wigner for one-dimensional lattice models, but now two-dimensional ana ...

*

Newton–Wigner localization Newton–Wigner localization (named after Theodore Duddell Newton and Eugene Wigner) is a scheme for obtaining a position operator for massive relativistic quantum particle In quantum field theory, the energy that a particle has as a result of ...

* Polynomial Wigner–Ville distribution *

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(pa ...

*

Thomas–Wigner rotation In physics, the Thomas precession, named after Llewellyn Thomas, is a Theory of relativity, relativistic correction that applies to the Spin (physics), spin of an elementary particle or the rotation of a macroscopic gyroscope and relates the an ...

*

Wigner–Eckart theorem The Wigner–Eckart theorem is a theorem of representation theory and quantum mechanics. It states that matrix elements of spherical tensor operators in the basis of angular momentum eigenstates can be expressed as the product of two factors, one o ...

*

Wigner–Inonu contraction In theoretical physics, Eugene Wigner and Erdal İnönü have discussed the possibility to obtain from a given Lie group a different (non-isomorphic) Lie group by a group contraction with respect to a continuous subgroup of it. That amounts to a l ...

*

Wigner–Seitz cell The Wigner–Seitz cell, named after Eugene Wigner and Frederick Seitz, is a primitive cell which has been constructed by applying Voronoi decomposition to a crystal lattice. It is used in the study of crystalline materials in crystallography. ...

*

Wigner–Seitz radius The Wigner–Seitz radius r_, named after Eugene Wigner and Frederick Seitz, is the radius of a sphere whose volume is equal to the mean volume per atom in a solid (for first group metals). In the more general case of metals having more valence ...

*

Wigner–Weyl transform In quantum mechanics, the Wigner–Weyl transform or Weyl–Wigner transform (after Hermann Weyl and Eugene Wigner) is the invertible mapping between functions in the quantum phase space formulation and Hilbert space operators in the Schrödin ...

*

Wigner–Wilkins spectrum Jesse Ernest Wilkins Jr. (November 27, 1923 – May 1, 2011) was an African American nuclear scientist, mechanical engineer and mathematician. A child prodigy, he attended the University of Chicago at the age of 13, becoming its youngest ever s ...

*

Wigner's classification In mathematics and theoretical physics, Wigner's classification is a classification of the nonnegative ~ (~E \ge 0~)~ energy irreducible unitary representations of the Poincaré group which have either finite or zero mass eigenvalues. (Since this ...

* *

Wigner's friend Wigner's friend is a thought experiment in theoretical quantum physics, first conceived by the physicist Eugene Wigner in 1961, Reprinted in and further developed by David Deutsch in 1985. The scenario involves an indirect observation of a quantum ...

*

Wigner's theorem Wigner's theorem, proved by Eugene Wigner in 1931, is a cornerstone of the mathematical formulation of quantum mechanics. The theorem specifies how physical symmetries such as rotations, translations, and CPT are represented on the Hilbert spac ...

*

Wigner crystal A Wigner crystal is the solid (crystalline) phase of electrons first predicted by Eugene Wigner in 1934. A gas of electrons moving in a uniform, inert, neutralizing background (i.e. Jellium Model) will crystallize and form a lattice if the electr ...

*

Wigner D-matrix The Wigner D-matrix is a unitary matrix in an irreducible representation of the groups SU(2) and SO(3). It was introduced in 1927 by Eugene Wigner, and plays a fundamental role in the quantum mechanical theory of angular momentum. The complex conjug ...

*

Wigner effect The Wigner effect (named for its discoverer, Eugene Wigner), also known as the discomposition effect or Wigner's disease, is the displacement of atoms in a solid caused by neutron radiation. Any solid can display the Wigner effect. The effect is ...

*

Wigner energy Eugene Paul "E. P." Wigner ( hu, Wigner Jenő Pál, ; 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 con ...

*

Wigner lattice A Wigner crystal is the solid (crystalline) phase of electrons first predicted by Eugene Wigner in 1934. A gas of electrons moving in a uniform, inert, neutralizing background (i.e. Jellium Model) will crystallize and form a lattice if the electr ...

* Wigner's disease *

Thomas–Wigner rotation In physics, the Thomas precession, named after Llewellyn Thomas, is a Theory of relativity, relativistic correction that applies to the Spin (physics), spin of an elementary particle or the rotation of a macroscopic gyroscope and relates the an ...

*

Von Neumann–Wigner interpretation The von Neumann–Wigner interpretation, also described as "''consciousness causes collapse''", is an interpretation of quantum mechanics in which consciousness is postulated to be necessary for the completion of the process of quantum measurement. ...

* Wigner-Witmer correlation rules ;Mathematics *

Gabor–Wigner transform The Gabor transform, named after Dennis Gabor, and the Wigner distribution function, named after Eugene Wigner, are both tools for time-frequency analysis. Since the Gabor transform does not have high clarity, and the Wigner distribution function ha ...

*

Modified Wigner distribution function :''Note: the Wigner distribution function is abbreviated here as WD rather than WDF as used at Wigner distribution function'' A Modified Wigner distribution function is a variation of the Wigner distribution function (WD) with reduced or removed c ...

*

Wigner distribution function The Wigner distribution function (WDF) is used in signal processing as a transform in time-frequency analysis. The WDF was first proposed in physics to account for quantum corrections to classical statistical mechanics in 1932 by Eugene Wigner, ...

*

Wigner semicircle distribution The Wigner semicircle distribution, named after the physicist Eugene Wigner, is the probability distribution on minus;''R'', ''R''whose probability density function ''f'' is a scaled semicircle (i.e., a semi-ellipse) centered at (0, 0): :f(x)=\sq ...

*

Wigner rotation In theoretical physics, the composition of two non-collinear Lorentz boosts results in a Lorentz transformation that is not a pure boost but is the composition of a boost and a rotation. This rotation is called Thomas rotation, Thomas–Wigner r ...

*

Wigner quasi-probability distribution The Wigner quasiprobability distribution (also called the Wigner function or the Wigner–Ville distribution, after Eugene Wigner and :fr:Jean Ville, Jean-André Ville) is a quasiprobability distribution. It was introduced by Eugene Wigner in 193 ...

*

Wigner semicircle distribution The Wigner semicircle distribution, named after the physicist Eugene Wigner, is the probability distribution on minus;''R'', ''R''whose probability density function ''f'' is a scaled semicircle (i.e., a semi-ellipse) centered at (0, 0): :f(x)=\sq ...

*

6-j symbol Wigner's 6-''j'' symbols were introduced by Eugene Paul Wigner in 1940 and published in 1965. They are defined as a sum over products of four Wigner 3-j symbols, : \begin j_1 & j_2 & j_3\\ j_4 & j_5 & j_6 \end = \sum_ (-1)^ \beg ...

*

9-j symbol In physics, Wigner's 9-''j'' symbols were introduced by Eugene Paul Wigner in 1937. They are related to recoupling coefficients in quantum mechanics involving four angular momenta \sqrt \begin j_1 & j_2 & j_3\\ j_4 & j_5 & j_6\\ ...

*

Wigner 3-j symbols In quantum mechanics, the Wigner 3-j symbols, also called 3''-jm'' symbols, are an alternative to Clebsch–Gordan coefficients for the purpose of adding angular momenta. While the two approaches address exactly the same physical problem, the 3-''j' ...

* Wigner–İnönü

group contraction In theoretical physics, Eugene Wigner and Erdal İnönü have discussed the possibility to obtain from a given Lie group a different (non-isomorphic) Lie group by a group contraction with respect to a continuous subgroup of it. That amounts to a ...

*

Wigner surmise In mathematical physics, the Wigner surmise is a statement about the probability distribution of the spaces between points in the spectra of nuclei of heavy atoms, which have many degrees of freedom, or quantum systems with few degrees of freedom ...

Notes

References

* * * *

N. Mukunda Narasimhaiengar Mukunda (born 25 January 1939, New Delhi, India) is an Indian theoretical physicist. Mukunda's higher education began at Delhi University, where he was granted a B.Sc. (Hon) degree in 1953. For his Ph.D. he studied at University ...

(1995) "Eugene Paul Wigner – A tribute",

Current Science ''Current Science'' is an English-language peer-reviewed multidisciplinary scientific journal. It was established in 1932 and is published by the Current Science Association along with the Indian Academy of Sciences. According to the ''Journal C ...

69(4): 375–85 * * * * *

External links

1964 Audio Interview with Eugene Wigner by Stephane Groueff
Voices of the Manhattan Project * * * * * *

Description of the childhood and especially of the school-years in Budapest, with some interesting photos too.
Interview with Eugene P. Wigner on John von Neumann
at the

Charles Babbage Institute The IT History Society (ITHS) is an organization that supports the history and scholarship of information technology by encouraging, fostering, and facilitating archival and historical research. Formerly known as the Charles Babbage Foundation, ...

, University of Minnesota, Minneapolis – Wigner talks about his association with

John von Neumann John von Neumann (; hu, Neumann János Lajos, ; December 28, 1903 – February 8, 1957) was a Hungarian-American mathematician, physicist, computer scientist, engineer and polymath. He was regarded as having perhaps the widest cove ...

during their school years in Hungary, their graduate studies in Berlin, and their appointments to Princeton in 1930. Wigner discusses von Neumann's contributions to the theory of quantum mechanics, Wigner's own work in this area, and von Neumann's interest in the application of theory to the atomic bomb project. * * including the Nobel Lecture, December 12, 1963 ''Events, Laws of Nature, and Invariance Principles'' {{DEFAULTSORT:Wigner, Eugene Paul 1902 births 1995 deaths Nobel laureates in Physics American Nobel laureates Hungarian Nobel laureates Austro-Hungarian Nobel laureates 20th-century Hungarian mathematicians American atheists Jewish atheists American Lutherans 20th-century American physicists American people of Hungarian-Jewish descent Atoms for Peace Award recipients Technical University of Berlin alumni Burials at Princeton Cemetery Enrico Fermi Award recipients Fasori Gimnázium alumni Fellows of the American Physical Society Foreign Members of the Royal Society Hungarian emigrants to the United States Hungarian atheists Hungarian Jews Hungarian Lutherans 20th-century Hungarian physicists Hungarian nuclear physicists Jewish American scientists Jewish physicists Manhattan Project people Mathematical physicists Members of the United States National Academy of Sciences National Medal of Science laureates Oak Ridge National Laboratory people People from Pest, Hungary Princeton University faculty Theoretical physicists University of Göttingen faculty University of Wisconsin–Madison faculty Winners of the Max Planck Medal Austro-Hungarian mathematicians Deaths from pneumonia in New Jersey People with acquired American citizenship Presidents of the American Physical Society

Early life

Middle years

Manhattan Project

Later years

Publications

Selected contributions

See also

Notes

References

External links