Hans Reichardt

Hans Reichardt (born April 2, 1908 in Altenburg , † April 4, 1991 in Berlin ) was a German mathematician who dealt with number theory , the history of mathematics and differential geometry .

Life

Reichardt was the son of a doctor, attended the humanistic high school in Altenburg and studied from 1926 at the universities of Jena , Königsberg , the Humboldt University Berlin (from 1928, especially with Issai Schur , where he heard algebraic number theory), Hamburg (with Erich Hecke and Emil Artin ) and the University of Marburg Mathematics, Physics and Philosophy. In 1932 he received his doctorate under Helmut Hasse in Marburg ( arithmetic theory of cubic bodies as radical bodies ). In 1933 he joined the NSDAP . In 1934 he passed his teaching degree and became an assistant at the University of Frankfurt under Carl Ludwig Siegel and in 1935 in Jena under Friedrich Karl Schmidt . In 1937 he went to the University of Leipzig to Bartel Leendert van der Waerden , where he completed his habilitation in 1939 ( on the Diophantine equation ${\displaystyle ax+bx^{2}y^{2}+cy=ez^{2}}$ ) and became a lecturer in 1940. During the war, he was with Telefunken in Berlin from 1943 . After the war he was in the Soviet Union from 1946 to 1952, where he worked on problems with missile technology on the island of Gorodomlja (today the Solnetschny settlement ) in Lake Seliger (Volga headwaters). From 1952 he was back in Germany and professor at the Humboldt University in Berlin, from 1955 as director of the 1st Mathematical Institute. From 1959 he was director of the Institute for Pure Mathematics of the German Academy of Sciences in Berlin, where he headed the number theory research group. In 1973 he retired.

He had numerous students in Berlin. His doctoral students include Helmut Boseck , Helmut Koch , Rolf Sulanke and Manfred Peschel . Since 1962 he was a corresponding and since 1964 a full member of the German Academy of Sciences in Berlin and since 1962 a member of the Leopoldina . In 1961 and 1966 he received the GDR National Prize for Science and Technology . In 1960 he was awarded the Patriotic Order of Merit in bronze. He was on the editorial board of the Journal for Pure and Applied Mathematics .

Reichardt was one of the initiators of the Mathematics Olympiads in the GDR in the early 1960s and, together with Heinrich Grell, the "Heinrich Hertz" Advanced High School in Berlin, which specializes in mathematics and physics .

plant

In the 1930s he worked, among other things, on inverse Galois theory in algebraic number theory (he showed the solvability in the case of a p-group with an odd prime number p; independently also shown by Arnold Scholz ). The work was continued in the 1950s by Dmitri Konstantinowitsch Faddejew and Igor Schafarewitsch in Russia, and in Germany in the 1970s by Jürgen Neukirch . Reichardt also dealt with arithmetic on elliptic curves and showed in 1942 that Hasse's local-global principle does not apply to elliptic curves in general: he gave the counterexample of an elliptic curve that has no rational solution, but p-adic and real solutions. After the war he turned increasingly to differential geometry and from the 1970s to the history of mathematics, in particular to Carl Friedrich Gauß , about whom he also wrote the article in the Encyclopædia Britannica 1974.

Fonts

• with Wilhelm Blaschke : Introduction to differential geometry. Springer Basic Teachings of Mathematical Sciences. 2nd edition 1960.
• Lectures on vector and tensor calculus (= university books for mathematics . Vol. 34). Deutscher Verlag der Wissenschaften, Berlin 1957, 2nd edition 1968.
• (Ed.): Gauss commemorative volume. Published on the occasion of the 100th anniversary of death on February 23, 1955. Teubner, 1957.
• Gauss and non-Euclidean geometry. Teubner, 1976.
• with Johannes Böhm (ed.): Gaussian surface theory, Riemannian spaces and Minkowski world (= Teubner archive for mathematics. 1). 1985 (works by Carl Friedrich Gauß , Bernhard Riemann , Hermann Minkowski are also printed and commented here).
• Gauss and the beginnings of non-Euclidean geometry. With original works by J. Bolyai, NI Lobatschewski and F. Klein (= Teubner Archive for Mathematics. 4). 1985 (works by Johann Bolyai , Nikolai Iwanowitsch Lobatschewski , Felix Klein are also printed and commented here).
• (Ed.): Obituaries for Berlin mathematicians of the 19th century (= Teubner Archive for Mathematics. 10). 1989 ( Carl Gustav Jacobi , Ernst Eduard Kummer , Peter Gustav Lejeune Dirichlet , Karl Weierstraß , Leopold Kronecker ).
• Gauss. In Hans Wußing , Wolfgang Arnold (ed.): Biographies of important mathematicians. People and Knowledge, Berlin 1975.
• Ed .: Artificial earth satellites. Translation from Russian. Academy, Berlin 1959 ( Advances in Physics. Special Volume 2).

literature

• Helmut Koch : Obituary for Hans Reichardt. Annual report of DMV 95, No. 4, 1993, pp. 135-140. (retro-digitized: [1] )
• Annette Vogt:  Reichardt, Hans . In: Who was who in the GDR? 5th edition. Volume 2. Ch. Links, Berlin 2010, ISBN 978-3-86153-561-4 .
• Hannelore Bernhardt : Hans Reichardt (1908-1991). In: Nuncius Hamburgensis Volume 36, Festschrift - Proceedings of the Scriba Memorial Meeting, Wiss. Coll. Of the specialist groups in the history of mathematics in the German Mathematicians Association (DMV) and the Society for Didactics (GDM), Ed. Gudrun Wolfschmidt, Hamburg: tredition 2017, pp. 468–479.

Web links

• Hans Reichardt in the Mathematics Genealogy Project (English)
• Teubner archive on mathematics

Individual evidence

1. ↑ Hans Reichardt: Arithmetic theory of the cubic body as a radical body . In: Mh. F. Math. And Phys . tape 40 , no. 1 , 1933, pp. 323-350 , doi : 10.1007 / BF01708874 .
2. ^ Harry Waibel : Servants of many gentlemen: Former Nazi functionaries in the Soviet Zone / GDR. Lang, Frankfurt am Main 2011, ISBN 978-3-631-63542-1 .
3. ↑ Hans Reichardt: About the Diophantine equation ax + bx ^ 2y ^ 2 + cy = ez ^ 2 , Math. Ann. 117, 1940, pp. 235-276
4. ^ Staatsrat honored outstanding personalities , In: Neues Deutschland , November 12, 1960, p. 2.
5. ^ Annette Vogt:  Reichardt, Hans . In: Who was who in the GDR? 5th edition. Volume 2. Ch. Links, Berlin 2010, ISBN 978-3-86153-561-4 .
6. ↑ Hans Reichardt: Construction of number fields with a given Galois group of prime power order , J. f. pure u. Applied Math. 177, 1937, pp. 1-5.
7. ↑ Hans Reichardt: Some Diophantine equations that can be solved everywhere on a small scale and unsolvable on a large scale , J. f. pure u. Applied Math. 184, 1942, pp. 12-18.