Heinrich Liebmann

Karl Otto Heinrich Liebmann (1874–1939)

Karl Otto Heinrich Liebmann (born October 22, 1874 in Strasbourg ; † June 12, 1939 in Munich-Solln ) was a German mathematician who dealt with geometry.

Life

Liebmann was the son of the Jena philosophy professor and neo-Kantian Otto Liebmann (1840–1912). The son studied at the universities of Leipzig , Jena and Göttingen from 1895 to 1897 . In 1895 he was in Jena at Carl Johannes Thomae with the theme The einzweideutigen projective point affinities of the plane to the doctor philosophiae and took off there in 1896 teaching certificate. In 1897 he was an assistant at Göttingen and in 1898 in Leipzig, where he joined in 1899 with the theme of the bending of closed surfaces of positive curvature About habilitated . In this work he proved, among other things, the Liebmann theorem, which is named after him today , with which he classified contiguous compact surfaces with constant Gaussian curvature .

In 1905 Liebmann became associate professor in Leipzig, in 1910 associate professor at the Technical University of Munich , and in 1915 he became professor there. In 1920 he succeeded Paul Stäckel as a professor at the University of Heidelberg , where he was rector in 1926 and dean of the Faculty of Mathematics and Natural Sciences in 1923/1924 and 1928/1929. In 1935, in response to political pressure from the National Socialists , he asked for retirement (Liebmann had Jewish ancestors, but was Protestant). He and his colleague Arthur Rosenthal were boycotted in his faculty . He spent his last years in Munich.

In 1913 he married his first wife Natalie Liebmann, née Kraus († 1924). She was the daughter of Karl Kraus, a professor of agricultural science at Munich University . After the death of his first wife, he married his second wife, Helene Ehlers, in 1926. So he was married twice and had four children.

Liebmann occupied himself a. a. with differential geometry and non-Euclidean geometry . He found the construction of a triangle from its three angles with compasses and ruler in hyperbolic geometry . In his habilitation, he proved that a convex closed surface cannot be bent ( Minding's theorem ).

He also translated Lobachevsky's works into German.

Liebmann was a member of the Saxon , Bavarian and Heidelberg Academy of Sciences .

Works (selection)

• The unambiguous projective point relationships of the plane. Jena, 1895 ( digitized from Heidelberg University )
• About the bending of the closed surfaces of positive curvature Leipzig 1900 ( digitalisat Univ. Heidelberg )
• Differential equations textbook . Leipzig 1901
• The non-Euclidean geometry. Historically critical presentation of their development . Berlin 1908, 1912, 1923 (together with Roberto Bonola )
• Synthetic geometry . Leipzig 1934
• Non-Euclidean Geometry. Leipzig 1905.
• The problem of the division of circles. Leipzig / Berlin 1913.
• The touch transformations, history and invariant theory. Leipzig 1914.
• Lie and Gambier's theorems about the curves of your line complex. Berlin 1928.

• NJ Lobachefsky's imaginary geometry and application of imaginary geometry to some integrals , 1904
• "A new property of the sphere", Mitteilungen Akademie Göttingen 1899
• The elementary constructions of non-Euclidean geometry , annual report DMV 1911
• “Necessity and freedom in mathematics”, annual report DMV 1905, inaugural lecture Leipzig
• “New proof of Minding's theorem”, DMV 1903 annual report
• “New proof of the theorem that a closed convex surface cannot be bent”, Mathematische Annalen Vol. 54, 1901
• "Geometrical theory of differential equations", Encyclopedia of Mathematical Sciences 1914
• "Touch Transformations", Encyclopedia of Mathematical Sciences 1914

literature

• Gottlob Kirschmer:  Liebmann, Heinrich. In: New German Biography (NDB). Volume 14, Duncker & Humblot, Berlin 1985, ISBN 3-428-00195-8 , p. 508 ( digitized version ).
• Siegfried Gottwald , Hans J. Ilgauds, Karl H. Schlote (ed.): Lexicon of important mathematicians . Bibliographisches Institut, Leipzig 1990, ISBN 3-323-00319-5 .
• Gabriele Dörflinger: Heinrich Liebmann - mathematician . In: Badische Biographien , New Series, Volume 6 (2011), pp. 258–259. ( Manuscript. )
• Dorothee Mußgnug: The expelled Heidelberg lecturers: on the history of the Ruprecht-Karls-Universität after 1933. Heidelberg 1988
• Heinrich Liebmann: The necessity of freedom in mathematics (Leipzig inaugural lecture) in: Herbert Beckert, Walter Purkert Leipzig mathematical inaugural lectures. Selection from the years 1869–1922 , BG Teubner, Leipzig 1987 (with biography)

Web links

• Gabriele Dörflinger: Heinrich Liebmann . A collection of material from Historia Mathematica Heidelbergensis .
• Heinrich Liebmann in the professorial catalog of the University of Leipzig
• Overview of Heinrich Liebmann's courses at the University of Leipzig (summer semester 1900 to winter semester 1910)

Individual evidence

1. ↑ Professor catalog of the University of Leipzig | catalogus professorum lipsiensium
2. ↑ Cf. Gabriele Dörflinger: Mathematics in the Heidelberg Academy of Sciences . 2014. pp. 47–49.