Karl Heinrich Gräffe

Karl Heinrich Gräffe (born November 7, 1799 in Braunschweig , † December 2, 1873 in Zurich ) was a German mathematician.

He was the son of a jeweler from Bremen and learned the goldsmith's trade in Hanover. Since his father had emigrated to the United States, he first had to continue his father's business to support his family. It was not until 1821 that he was able to follow his inclination and attended the Carolinum in Braunschweig and then from 1824 studied mathematics at the University of Göttingen with Carl Friedrich Gauß , Johann Tobias Mayer and Bernhard Friedrich Thibaut, among others . After receiving his doctorate in 1825 ( The history of the calculus of variations from the origin of differential and integral calculus to the present day ), he taught at the then newly founded Technical Institute in Zurich . He wrote several textbooks for teaching there.

He is known for a method for the numerical solution of algebraic equations, the Dandelin-Gräffe method, independent of Germinal Pierre Dandelin (1823) and Nikolai Iwanowitsch Lobatschewski (published in his textbook on higher algebra in 1834), which he developed from 1833. It was published in 1837 ( The Resolution of Higher Numerical Equations ). In 1838 he took part in a competition at the Berlin Academy, but failed for formal reasons (contrary to the rules, his treatise had already been printed).

In 1833 he became a professor at the Upper Industrial School in Zurich and was also a private lecturer at the University of Zurich, which was founded in the same year. In 1860 he became an associate professor at the university. For health reasons, he retired from the industrial school in 1868. Previously, he had been passed over in the assignment of a full professorship for mathematics at the University of Zurich, which also affected him.

Fonts

• The resolution of the higher numerical equations. Verlag Friedrich Schulthess, Zurich 1837, Internet Archive .
  • Supplements to this appeared in the program of the Zurich Cantons School in 1839.

literature

• Moritz Cantor :  Counts, Karl Heinrich . In: Allgemeine Deutsche Biographie (ADB). Volume 9, Duncker & Humblot, Leipzig 1879, pp. 572-574.
• Johann Jakob Burckhardt:  Counts, Karl Heinrich. In: New German Biography (NDB). Volume 6, Duncker & Humblot, Berlin 1964, ISBN 3-428-00187-7 , p. 713 f. ( Digitized version ).

Web links

• John J. O'Connor, Edmund F. Robertson :  Karl Heinrich Gräffe. In: MacTutor History of Mathematics archive .
• Overview of Karl Heinrich Gräffe's courses at the University of Zurich (summer semester 1833 to winter semester 1866)