Wolfgang Haken

Wolfgang hook ( born June 21, 1928 in Berlin ) is a German - American mathematician specializing in topology ( in particular 3- dimensional manifolds ), in 1976, the four-color problem was solved with Kenneth Appel.

Life and work

Hook studied mathematics, physics and philosophy in Kiel, where he received his doctorate in 1953 with Karl - Heinrich Weise on a theme of the topology. 1954 to 1962 he was with Siemens in Munich, where he specialized in applications of microwave technology. Besides, he published papers on topology and its node algorithm gave him an invitation to the University of Illinois, where he became professor in 1965 ( and currently is a professor emeritus yet). In 1976 he proved together with Kenneth Appel ( who has worked at the time, as well as hooks, at the University of Illinois ), the famous four- color theorem. On the computer evidence they worked about 4 years since 1972. Evidence was reviewed in the 1980s in part, where there were two errors that could be corrected though. Independent evidence was by Frank Allaire (1977, but never published in full ) and led by Paul Seymour, Neil Robertson, Daniel Sanders and Robin Thomas 1993 ( the only 633 instead of 1,900 and later 1,400 unavoidable reducible configurations of Appel and Haken had ), but all use the computer.

In topology, the hook -manifolds are named after him and here he is interested in algorithmic questions. For example, come from him, an algorithm for deciding whether a node in a closed curve is "real" or can be unknotted ( with his theory of normal surfaces ). Hooks also extended the theory of normal surfaces by Hellmuth Kneser.

In 1993 he received an honorary doctorate from the Johann Wolfgang Goethe University Frankfurt am Main. In 1979 he was awarded the Fulkerson Prize for discrete mathematics with Appel. In 1978 he was invited speaker at the International Congress of Mathematicians in Helsinki ( Combinatorial aspects of some mathematical problems ).

In 1990 he became a member of the " Center for Advanced Study ", University of Illinois, where he among other things, working to improve its node algorithm.

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