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Helmut Heinrich Schaefer | |
|---|---|
 Helmut Schaefer in 1989 | |
| Born | (1925-02-14)February 14, 1925 |
| Died | December 16, 2005(2005-12-16) (aged 80) Tübingen, Germany |
| Education | TU Dresden University of Leipzig |
| Known for | Work ontopological vector spaces,Schaefer's fixed point theorem |
| Scientific career | |
| Institutions | University of Halle University of Mainz Washington State University University of Michigan University of Tübingen |
| Doctoral advisor | Ernst Hölder |
| Other academic advisors | Gottfried Köthe |
| Doctoral students | Bertram John Walsh |
Helmut Heinrich Schaefer (February 14, 1925 inGroßenhain,Weimar Republic – December 16, 2005 inTübingen, Germany) was a German mathematician, who worked primarily infunctional analysis. His two best known scientific monographs are titledTopological Vector Spaces (1966) andBanach Latticesand Positive Operators (1974). The first of these was subsequently translated into Spanish and Russian. The second made him an internationally recognized and leading scholar in this particular field of mathematics. (Roquette & Wolff, 2006)
As teenager, Helmut Schaefer attended theSankt Afra boarding school for gifted children inMeissen, Germany on a merit-based scholarship. In 1943, then 18, he was recruited to serve as interpreter of Anglo-American intelligence. After the war he studied mathematics atTU Dresden andUniversity of Leipzig, where he earned his doctorate in 1951 and hishabilitation in 1954. Prof.Ernst Hölder served as his academic advisor in Leipzig. In 1956 he accepted an offer from theUniversity of Halle as professor of mathematics.
In 1957, Schaefer, his wife and two children escaped fromEast Germany to the Federal Republic. For one year, he worked under Prof.Gottfried Köthe at theUniversity of Mainz. In 1958 he became Associate Professor atWashington State University at Pullman and a few years later he, his wife and now three children moved on to theUniversity of Michigan atAnn Arbor. Then in 1963 he accepted an offer from theUniversity of Tübingen in Germany where he remained until his retirement in 1990. In Tübingen he served two terms as department head.
Interrupting this period on several occasions and following retirement in Tübingen he spent a number of one-year terms or semesters as visiting or full professor at various American universities, including theUniversity of Illinois Urbana-Champaign, theUniversity of Maryland at College Park, theCalifornia Institute of Technology in Pasadena, Texas A&M University at College Station, andFlorida Atlantic University at Boca Raton. He remained active in mathematical research until the year 1999, at which point he completely dedicated himself to his lifelong hobby of astronomy, especiallyastrophotography.
In 1978, Helmut Schaefer was accepted as full member of the Mathematics and Natural Sciences Class of theHeidelberg Academy of Sciences. Earlier, he was admitted to the Academy of Sciences in Zaragoza (Spain). Over the years, he was able to attract many students to functional analysis, combining an expectation of high achievement with a tolerant, humorous, and factual attitude. Ten of his doctoral students went on to become professors at various universities in Germany and the U.S. (Roquette & Wolff, 2006) His doctoral students includeWolfgang Arendt (de),Rainer Nagel (de), andBertram John Walsh.
