Andreas von Ettingshausen | |
|---|---|
 | |
| Born | 25 November 1796 |
| Died | 25 May 1878 (aged 81) |
| Alma mater | University of Vienna |
| Known for | Electric machines |
| Children | Carolina Augusta von Ettingshausen, grandmother of Rudolf Allers |
| Scientific career | |
| Fields | Physicist and mathematician |
| Institutions | University of Innsbruck University of Vienna Vienna Polytechnic Institute |
| Academic advisors | Ignaz Lindner[1] |
| Doctoral students | Ernst Mach Francesco Rossetti Jožef Stefan Viktor von Lang |
Andreas Freiherr von Ettingshausen (25 November 1796 – 25 May 1878) was an Austrian mathematician and physicist.
Ettingshausen studied philosophy and jurisprudence at the University of Vienna. In 1817, he joined the University of Vienna and taught mathematics and physics as an adjunct professor. In 1819, he became professor of physics at the University of Innsbruck and 1821 professor of higher mathematics at the University of Vienna. His lectures of that time marked a new era for the University of Vienna, and they were published in 1827 in two volumes. In 1834 Ettingshausen became the chair of physics.
Ettingshausen was the first to design an electromagnetic machine, which used the electrical induction for power generation. He promoted optics and wrote a textbook of physics. His method of lecturing was widely influential. In addition he wrote a book on combinatorial analysis (Vienna 1826). In 1866, he retired.
Among his lasting impacts in mathematics is the introduction of the notation for the binomial coefficient, which is the coefficient of in the expansion of the binomial and, more generally, the number of -element subsets of an -element set.[2][3]
His daughter Carolina Augusta von Ettingshausen was the grandmother of Rudolf Allers.
- ^ Andreas von Ettingshausen, Vorlesungen über die höhere Mathematik: Vorlesungen über die Analysis, Volume 1, Gerold, 1827, p. v.
- ^ Ettingshausen, Andreas von (1826). Die combinatorische Analysis als Vorbereitungslehre zum Studium der theoretischen höhern Mathematik [Combinatorial analysis as preparatory instruction for the study of theoretical higher mathematics] (in German). Vienna, Austria: J.B. Wallishauffer. pp. 30, 31. From p. 30: "Da wir im Folgenden sehr häufig Gelegenheit haben werden, von dem numerischen Ausdrucke dieser Menge Gebrauch zu machen, so wollen wir dafür das Zeichen (n k) wählen, und es mit dem Worten n über k ausprechen, wobei die obere Zahl stets die Anzahl der combinirten Elemente, die untere aber den Rang der Combinationsklasse angibt." (Since we will very frequently have occasion in the following to make use of numerical expressions of these quantities, then we will choose for that purpose the symbol (n k) and will express it with the words "n over k", whereby the upper number always specifies the number of combined elements whereas the lower [number] specifies the rank of the classes of combinations.) Page 31 shows that (n k) = n! / k! (n-k)! .
- ^ Nicholas J. Higham (1998). Handbook of Writing for the Mathematical Sciences. Society for Industrial and Applied Mathematics. p. 25. ISBN 0-89871-420-6.