Sigurdur Helgason

Helgason 1988

Sigurður Helgason (anglicized Sigurdur Helgason ; born September 30, 1927 in Akureyri , Iceland ) is an Icelandic mathematician who deals with harmonic analysis , differential geometry , Lie groups , integral geometry and differential equations on Lie groups.

life and work

Helgason studied at the University of Iceland in Reykjavik with a bachelor's degree in 1946 and at the University of Copenhagen with a master's degree in 1952. He received his doctorate in 1954 from Princeton University under Salomon Bochner ( Banach algebras and almost periodic functions ). From 1954 to 1956 he was a Moore Instructor at the Massachusetts Institute of Technology (MIT) and from 1957 to 1959 Louis Block Lecturer at the University of Chicago . In 1959 he became an assistant professor at MIT and in 1965 a professor. 1956/57 he was at Princeton University and 1959/60 visiting professor at Columbia University . 1964–1966, 1974/75, 1983/84 and 1998 he was at the Institute for Advanced Study in Princeton. In 1970/71 (and 1995) he was at the Mittag-Leffler Institute in Stockholm .

Helgason is known for his textbooks, for which he received the Leroy P. Steele Prize in 1988 , in particular for Differential geometry of symmetric spaces in 1962 (later expanded to two volumes), which became a model for the representation of differential geometry and the Lie groups in textbooks . According to Helgason's own words, it should represent harmonic (geometric) analysis on symmetrical spaces in analogy to the theory of Fourier and Radon transformation in Euclidean space .

Helgason is a member of the Icelandic and Royal Danish Academy of Sciences and the American Academy of Arts and Sciences (1970). He is a fellow of the American Mathematical Society . In 1951 he received the gold medal from the University of Copenhagen . In 1964/65 he was a Guggenheim Fellow . In 1970 he was invited speaker at the International Congress of Mathematicians in Nice (Group representations and symmetric spaces) and in 1962 in Stockholm (Some results in invariant theory). In 1986 he received an honorary doctorate from the University of Iceland , in 1996 in Uppsala and in 1988 from the University of Copenhagen, whose gold medal he also received. In 1991 he received the Great Knight's Cross of the Order of the Icelandic Falcon.

James Lepowsky is one of his doctoral students .

In 1957 he married Artie Gianopulos and has a son and a daughter.

Fonts (selection)

• Differential geometry and symmetric spaces (= Pure and Applied Mathematics. 12, ISSN  0079-8169 ). Academic Press, New York NY et al. 1962.
• Analysis on Lie groups and homogeneous spaces. American Mathematical Society, Providence RI 1972, ISBN 0-8218-1664-0 .
• Differential geometry, Lie groups and symmetric spaces (= Pure and Applied Mathematics. 80). Academic Press, New York NY et al. 1978, ISBN 0-12-338460-5 .
• The Radon Transform (= Progress in Mathematics. 5). Birkhäuser, Boston MA et al. 1980, ISBN 3-7643-3006-6 (2nd edition, ibid. 1999, ISBN 3-7643-4109-2 ).
• Topics in harmonic analysis on homogeneous spaces (= Progress in Mathematics. 13). Birkhäuser, Boston MA et al. 1981, ISBN 3-7643-3051-1 .
• Groups and geometric analysis. Integral geometry, invariant differential operators and spherical functions (= Pure and Applied Mathematics. 113). Academic Press, Orlando FL et al. 1984, ISBN 0-12-338301-3 .

literature

• Interview in: Joel Segel (Ed.): Recountings. Conversations with MIT mathematicians. AK Peters, Wellesley MA 2009, ISBN 978-1-568-81449-0 , pp. 411-441.

Web links

• Literature by and about Sigurður Helgason in the catalog of the German National Library
• Web site Sigurdur Helgason (English)
• Sigurður Helgason in the Mathematics Genealogy Project (English)
• List of publications

Individual evidence

1. ↑ Pamela Kalte u. a. American Men and Women of Science , Thomson Gale 2004

Note: Icelanders are referred to by their first name or first and last name, but not just their surname. Further information can be found under Icelandic personal name .