Wilhelm Blaschke

Wilhelm Johann Eugen Blaschke (* September 13, 1885 in Graz, † March 17, 1962 in Hamburg) was an Austrian mathematician and author. His works have influenced the development of modern differential geometry crucial.

Life and work

His father Josef Blaschke (1852-1917) taught descriptive geometry at the secondary school in Graz and influenced his son early in the sense of purely geometrical proofs of Jakob Steiner. At the University of Vienna, he studied architecture before he switched to mathematics and his doctorate under Wilhelm Wirtinger 1908. He then went to Pisa to Luigi Bianchi and to Göttingen to Felix Klein, David Hilbert and Carl Runge. In 1910 he habilitated with Eduard Study in Bonn. Before he became a professor in 1913 in Prague, he still worked in Greifswald with the Lie - pupil Friedrich Engel. In 1915 he went to Leipzig, where he, in his inaugural lecture " circle and sphere " Jakob Steiner traces follows in 1917 to Königsberg and from there via Tübingen in 1919 to Hamburg, he with the appeal, inter alia, by Erich Hecke and Emil Artin into a center for mathematics made. There he remained until his retirement in 1953, but retained even after a brisk traveling at.

Blaschke worked in many areas of the differential geometry ( particularly affinity differential geometry ) and the geometry of, for example, on minimum properties (" isoperimetric properties " ) of geometric figures convex body, integral geometry, and the geometry of the "tissue", Group theoretical properties of geometry, the geometry of the circles and spheres (after Edmond Laguerre, August Ferdinand Möbius, Sophus Lie). In function theory the Blaschkeprodukt is named after him, and also the convergence theorem of Blaschke and the selection set of Blaschke.

He is the author of many excellent textbooks, especially his "Lectures on Differential Geometry " from 1921 / 9th Even Felix Klein's lectures on higher geometry he has re-edited and completed.

Blaschke was opposed in the Nazi state initially against its insulation endeavor in the scientific field, was then a member of the NSDAP. On November 11, 1933, he was one of the callers of the commitment of professors at German universities and colleges to Adolf Hitler and the Nazi state.

Blaschke was controversial in the postwar years. It was founded in 1946 " denazification " and got his chair back in Hamburg, which he retained until his retirement in 1953. But he had also many international contacts. Among his students is one of the internationally leading after the Second World War Geometer Shiing - Shen Chern, who earned his doctorate at him in 1936, Gerhard Thomsen and Luis Santaló. Another employee was Gerrit Bol.

On April 4, 1957 Blaschke was admitted as an honorary member of the German Academy of Sciences in Berlin. He was also a member of the Leopoldina since 1943.

A conjecture of Blaschke on the characterization of the n-dimensional sphere as a reunion manifold was proved by Jerry Kazdan, Marcel Berger, Alan Weinstein and Chung Tao Yang.

He was married in 1923 to Auguste Roettger ( 1893-1992 ) and they had a daughter ( born 1925 ) and a son ( 1930-2011 ). Blaschke scientific estate located in the Institute for the History of Science and Technology of the University of Hamburg.

The Wilhelm Blaschke Memorial Foundation (founded by Emanuel Sperner ) in Hamburg award in his honor a medal for achievements in geometry. Award winners have included Katsumi Nomizu and Kurt Leichtweiß.

Blaschke's grave is in the cemetery Ohlsdorf, near the main entrance.

Works

  • Collected Works, Thales, Food 1985
  • Circle and sphere, Leipzig, Veit 1916
  • Lectures on Differential Geometry, 3 vols, Springer, basic teachings of the mathematical sciences 1921-1929 ( Vol.1 Elementary Differential Geometry, Vol.2 Affine differential geometry, differential geometry Bd.3 of circles and spheres, 1929)
  • Non - Euclidean geometry and mechanics I, II, III. Leipzig: B.G.Teubner (1942 )
  • The movement geometry of the sphere. In: Proceedings of the Heidelberg Academy of Sciences ( 1948)
  • Kinematics and quaternions. Berlin: VEB German Academic Publishers (1960 )
  • H. Reichardt: Introduction to Differential Geometry. Springer (1960 )
  • With Kurt Leichtweiß: Elementary Differential Geometry. Berlin: Springer (5th edition 1973)
  • Speeches and traveling a surveyor. Berlin: VEB German Academic Publishers (1961, 2nd, extended edition. )
  • Mathematics and life, Wiesbaden, Steiner 1951
  • Projective geometry, 3.Aufl. , Birkhauser 1954
  • Analytic Geometry, 2nd ed. , Birkhauser 1954
  • Circle and sphere, 3.Aufl. , Berlin, de Gruyter 1956
  • Lectures on integral geometry, VEB, Berlin 1955
  • Plane kinematics, Oldenbourg, München 1956
  • Introduction to the geometry of the honeycombs, Birkhauser 1955
  • Greek and descriptive geometry, Oldenbourg 1953
Carl David Tolmé Runge Friedrich Engel (mathematician) Convex set Complex analysis Blaschke selection theorem German Academy of Sciences at Berlin Ernst Klee Karl Rathgen Georg Thilenius Otto Lauffer Ernst Cassirer Bruno Snell Karl Schiller Otto Brunner Helmut Thielicke Integrated Authority File
820833
de