Valentine "Valya" Bargmann (April 6, 1908 – July 20, 1989) was a German-American

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, mathematical structure, structure, space, Mathematica ...

and theoretical

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 ...

Biography

Born in Berlin,

Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ...

, to a

German Jewish The history of the Jews in Germany goes back at least to the year 321 CE, and continued through the Early Middle Ages (5th to 10th centuries CE) and High Middle Ages (c. 1000–1299 CE) when Jewish immigrants founded the Ashkenazi Jewish commu ...

family, Bargmann studied there from 1925 to 1933. After the National Socialist

Machtergreifung The rise to power of Adolf Hitler, dictator of Nazi Germany from 1933 to 1945, began in the newly established Weimar Republic in September 1919, when Hitler joined the '' Deutsche Arbeiterpartei'' (DAP; German Workers' Party). He quickly rose t ...

, he moved to Switzerland to the

University of Zürich The University of Zurich (UZH, ) is a public university, public research university in Zurich, Switzerland. It is the largest university in Switzerland, with its 28,000 enrolled students. It was founded in 1833 from the existing colleges of the ...

where he received his Ph.D. under

Gregor Wentzel Gregor Wentzel (17 February 1898 – 12 August 1978) was a German physicist known for development of quantum mechanics. Wentzel, Hendrik Kramers, and Léon Brillouin developed the Wentzel–Kramers–Brillouin approximation in 1926. In his early y ...

. He emigrated to the U.S., barely managing immigration acceptance, as his German passport was to be revoked with only two days of validity left. At the

Institute for Advanced Study The Institute for Advanced Study (IAS) is an independent center for theoretical research and intellectual inquiry located in Princeton, New Jersey. It has served as the academic home of internationally preeminent scholars, including Albert Ein ...

Princeton Princeton University is a private Ivy League research university in Princeton, New Jersey, United States. Founded in 1746 in Elizabeth as the College of New Jersey, Princeton is the fourth-oldest institution of higher education in the Unit ...

(1937–1946) he worked as an assistant to

Albert Einstein Albert Einstein (14 March 187918 April 1955) was a German-born theoretical physicist who is best known for developing the theory of relativity. Einstein also made important contributions to quantum mechanics. His mass–energy equivalence f ...

, publishing with him and

Peter Bergmann Peter Gabriel Bergmann (24 March 1915 – 19 October 2002) was a German-American physicist best known for his work with Albert Einstein on a unified field theory encompassing all physical interactions. He also introduced primary and seconda ...

on classical five-dimensional

Kaluza–Klein theory In physics, Kaluza–Klein theory (KK theory) is a classical unified field theory of gravitation and electromagnetism built around the idea of a fifth dimension beyond the common 4D of space and time and considered an important precursor to ...

(1941). He taught at

Princeton University Princeton University is a private university, private Ivy League research university in Princeton, New Jersey, United States. Founded in 1746 in Elizabeth, New Jersey, Elizabeth as the College of New Jersey, Princeton is the List of Colonial ...

from 1946 for the rest of his career. He pioneered understanding of the irreducible unitary representations of SL₂(R) and the

Lorentz group In physics and mathematics, the Lorentz group is the group of all Lorentz transformations of Minkowski spacetime, the classical and quantum setting for all (non-gravitational) physical phenomena. The Lorentz group is named for the Dutch physi ...

(1947). He further formulated the

Bargmann–Wigner equations In relativistic quantum mechanics and quantum field theory, the Bargmann–Wigner equations describe free particles with non-zero mass and arbitrary spin , an integer for bosons () or half-integer for fermions (). The solutions to the equations ...

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 ...

(1948), for particles of arbitrary spin, building up on work of several theorists who pioneered

quantum mechanics Quantum mechanics is the fundamental physical Scientific theory, theory that describes the behavior of matter and of light; its unusual characteristics typically occur at and below the scale of atoms. Reprinted, Addison-Wesley, 1989, It is ...

. Bargmann's theorem (1954) on projective unitary representations of

Lie group In mathematics, a Lie group (pronounced ) is a group (mathematics), group that is also a differentiable manifold, such that group multiplication and taking inverses are both differentiable. A manifold is a space that locally resembles Eucli ...

s gives a condition for when a projective unitary representation of a Lie group comes from an ordinary unitary representation of its universal cover. Bargmann further discovered the Bargmann–Michel–Telegdi equation (1959) describing relativistic precession; Bargmann's limit of the maximum number of QM bound states of a potential (1952); the notion of Bargmann potentialsV. Bargmann (1949). "On the Connection between Phase Shifts and Scattering Potential", Reviews of Modern Physics, 21(3), 488–493. doi:10.1103/revmodphys.21.488 for the radial Schrödinger equations with bound states but no non-trivial scattering, which play a basic role in the theory of

Soliton In mathematics and physics, a soliton is a nonlinear, self-reinforcing, localized wave packet that is , in that it preserves its shape while propagating freely, at constant velocity, and recovers it even after collisions with other such local ...

s, and the holomorphic representation in the

Segal–Bargmann space In mathematics, the Segal–Bargmann space (for Irving Segal and Valentine Bargmann), also known as the Bargmann space or Bargmann–Fock space, is the space of holomorphic functions ''F'' in ''n'' complex variables satisfying the square-integrabi ...

(1961), including the Bargmann kernel. Bargmann was elected a Fellow of the

American Academy of Arts and Sciences The American Academy of Arts and Sciences (The Academy) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, and other ...

in 1968. In 1978, he received the

Wigner Medal The International Colloquium on Group Theoretical Methods in Physics (ICGTMP) 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 tw ...

, together with Wigner himself, in the founding year of the prize. In 1979, Bargmann was elected to the US

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 1988, he received 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 ...

of the

German Physical Society The German Physical Society (German: , DPG) is the oldest organisation of physicists. As of 2022, the DPG's worldwide membership is cited as 52,220, making it one of the largest national physics societies in the world. The DPG's membership peaked ...

. He was also a talented pianist. He died in

in 1989.

References

External links

National Academy of Sciences Biographical Memoir
by J R Klauder

* * ttp://digilib.mpiwg-berlin.mpg.de/digitallibrary/servlet/Scaler?dw=425&dh=600&fn=permanent/einstein_exhibition/images/bargmann1& Photo from a website

Selected bibliography

*1934: "Über den Zusammenhang zwischen Semivektoren and Spinoren und die Reduktion der Diracgleichung für Semivektoren". ''Helv. Phys. Acta'' 7:57-82. *1936: "Zur Theorie des Wasserstoffatoms". ''Z. Phys.'' 99:576-82. *1937: "Über die durch Elektronenstrahlen in Kristallen angeregte Lichtemission". ''Helv. Phys. Acta'' 10:361-86. *1941: With A. Einstein and P. G. Bergmann. "On the five-dimensional representation of gravitation and electricity". In ''Theodore von Kármán Anniversary Volume'', pp. 212–25,(Pasadena, California Institute of Technology). *1944: With A. Einstein. "Bivector fields". ''Ann. Math.'' 45:1-14. *1945: "On the glancing reflection of shock waves". ''Applied Mathematics Panel Report No. 108'' *1946: With D. Montgomery and J. von Neumann. "Solution of linear systems of high order". Report to the Bureau of Ordinance, U. S. Navy. *1947: "Irreducible unitary representations of the Lorentz group". ''Ann. Math.'' 48:568-640. *1948: With E. P. Wigner. "Group theoretical discussion of relativistic wave equations". ''Proc. Natl. Acad. Sci. U.S.A.'' 34:211-23. *1949: "Remarks on the determination of a central field of force from the elastic scattering phase shifts". ''Phys. Rev.'' 75:301-303. * "On the connection between phase shifts and scattering potential". ''Rev. Mod. Phys.'' 21:488-93. *1952: "On the number of bound states in a central field of force". ''Proc. Natl. Acad. Sci. U.S.A.'' 38:961-66. *1954: "On unitary ray representations of continuous groups". ''Ann. Math.'' 59:1-46. *1959: With L. Michel and V. Telegdi. "Precession of the polarization of particles moving in a homogeneous electromagnetic field". ''Phys. Rev. Lett.'' 2:435-36. *1960: "Relativity". In ''Theoretical Physics in the Twentieth Century (Pauli Memorial Volume)'', eds., M. Fierz and V. F. Weisskopf, pp. 187–98. New York: Interscience Publishers. * With M. Moshinsky. "Group theory of harmonic oscillators. I. The collective modes". ''Nucl. Phys.'' 18:697-712. *1961: With M. Moshinsky. "Group theory of harmonic oscillators. II. The integrals of motion for the quadrupole-quadrupole interaction". ''Nucl. Phys.'' 23:177-99. * "On a Hilbert space of analytic functions and an associated integral transform. Part I." ''Commun. Pure Appl. Math.'' 14:187-214. *1962: "On the representations of the rotation group". ''Rev. Mod. Phys.'' 34:829-45. *1964: "Note on Wigner’s theorem on symmetry operations". ''J. Math. Phys.'' 5:862-68. *1967: "On a Hilbert space of analytic functions and an associated integral transform. Part II. A family of related function spaces application to distribution theory". ''Commun. Pure Appl. Math.'' 20:1-101. *1971: With P. Butera, L. Girardello, and J. R. Klauder. "On the completeness of the coherent states". ''Rep. Math. Phys.'' 2:221-28. *1972: "Notes on some integral inequalities". ''Helv. Phys. Acta'' 45:249-57. *1977: With I. T. Todorov. "Spaces of analytic functions on a complex cone as carriers for the symmetric tensor representations of SO(n)". ''J. Math. Phys.'' 18:1141-48. *1979: "Erinnerungen eines Assistanten Einsteins". Vierteljahrsschrift der Naturforschenden Gesellschaft in Zürich, Jahrgang 124, Heft 1, pp. 39–44. Zürich: Druck und Verlag Orell Fussli Graphische Betriebe AG. {{DEFAULTSORT:Bargmann, Valentine 1908 births 1989 deaths 20th-century American mathematicians 20th-century German mathematicians 20th-century American physicists Fellows of the American Academy of Arts and Sciences Members of the United States National Academy of Sciences 20th-century German physicists Jewish emigrants from Nazi Germany to the United States Institute for Advanced Study visiting scholars Mathematical physicists University of Zurich alumni Jewish American physicists Winners of the Max Planck Medal Jewish German physicists