Leo Reino Sario (18 May 1916 – 15 August 2009) was a Finnish-born mathematician who worked on

complex analysis Complex analysis, traditionally known as the theory of functions of a complex variable, is the branch of mathematical analysis that investigates Function (mathematics), functions of complex numbers. It is helpful in many branches of mathemati ...

and

Riemann surfaces In mathematics, particularly in complex analysis, a Riemann surface is a connected one-dimensional complex manifold. These surfaces were first studied by and are named after Bernhard Riemann. Riemann surfaces can be thought of as deformed versio ...

Early life and education

After service as a Finnish artillery officer in the

Winter War The Winter War,, sv, Vinterkriget, rus, Зи́мняя война́, r=Zimnyaya voyna. The names Soviet–Finnish War 1939–1940 (russian: link=no, Сове́тско-финская война́ 1939–1940) and Soviet–Finland War 1 ...

and World War II, he received his PhD in 1948 under

Rolf Nevanlinna Rolf Herman Nevanlinna (né Neovius; 22 October 1895 – 28 May 1980) was a Finnish mathematician who made significant contributions to complex analysis. Background Nevanlinna was born Rolf Herman Neovius, becoming Nevanlinna in 1906 when his fat ...

at the

University of Helsinki The University of Helsinki ( fi, Helsingin yliopisto, sv, Helsingfors universitet, abbreviated UH) is a public research university located in Helsinki, Finland since 1829, but founded in the city of Turku (in Swedish ''Åbo'') in 1640 as the ...

Career

Nevanlinna and Sario were founding members of the

Academy of Finland The Academy of Finland ( fi, Suomen Akatemia, sv, Finlands Akademi) is a governmental funding body for scientific research in Finland. It is based in Helsinki. Yearly, the Academy administers over 260 million euros to Finnish research activities. O ...

, and there is a statue on the Academy grounds named after Sario. Sario moved to the United States in 1950 and obtained temporary positions at the

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

,Sario, Leo Reino – Institute for Advanced Study Visiting Scholar
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MIT The Massachusetts Institute of Technology (MIT) is a private land-grant research university in Cambridge, Massachusetts. Established in 1861, MIT has played a key role in the development of modern technology and science, and is one of the mo ...

Stanford University Stanford University, officially Leland Stanford Junior University, is a private research university in Stanford, California. The campus occupies , among the largest in the United States, and enrolls over 17,000 students. Stanford is consider ...

, and

Harvard University Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher le ...

. In 1954 he became a professor at

UCLA The University of California, Los Angeles (UCLA) is a public land-grant research university in Los Angeles, California. UCLA's academic roots were established in 1881 as a teachers college then known as the southern branch of the California St ...

, remaining there until his retirement in 1986. He was the author or co-author of five major books on complex analysis and over 130 papers. He supervised 36 doctoral students, including Kōtarō Oikawa and

Burton Rodin Burton Rodin is an American mathematician known for his research in conformal mappings and Riemann surfaces. He is a professor emeritus at the University of California, San Diego. Education Rodin received a Ph.D. at the University of California, ...

Awards and honors

In 1957 he was awarded the Cross of the Commander of Finland's Order of Knighthood. He was a

Guggenheim Fellow Guggenheim Fellowships are grants that have been awarded annually since by the John Simon Guggenheim Memorial Foundation to those "who have demonstrated exceptional capacity for productive scholarship or exceptional creative ability in the ar ...

for the academic year 1957–1958.

Selected publications

*with

Lars Ahlfors Lars Valerian Ahlfors (18 April 1907 – 11 October 1996) was a Finnish mathematician, remembered for his work in the field of Riemann surfaces and his text on complex analysis. Background Ahlfors was born in Helsinki, Finland. His mother, S ...

: Riemann surfaces, Princeton Mathematical Series 26, Princeton University Press 19602015 pbk reprint
*with Kiyoshi Noshiro: Value Distribution Theory, Van Nostrand 19662013 pbk reprint
*with Burton Rodin: Principal Functions, Springer 1968, Van Nostrand 1968

*with Kōtarō Oikawa: Capacity Functions, Grundlehren der mathematischen Wissenschaften 149, Springer 1969 *with Mitsuru Nakai: Classification Theory of Riemann Surfaces, Grundlehren der mathematischen Wissenschaften 164, Springer 1970
2012 pbk reprint
*with Mitsuru Nakai, Cecilia Wang, Lung Ock Chung: Classification Theory of Riemannian Manifolds : Harmonic, quasiharmonic and biharmonic functions, Lecture Notes in Mathematics 605, Springer 1977
2006 pbk reprint
*Capacity of a boundary and of a boundary element, Annals of Mathematics, vol. 59, 1954, pp. 135–144

References

Complex analysts Mathematical analysts 20th-century Finnish mathematicians Finnish emigrants to the United States Institute for Advanced Study visiting scholars University of Helsinki alumni University of California, Los Angeles faculty 1916 births 2009 deaths {{mathematician-stub