Johann Andreas Segner | |
|---|---|
 Johann Andreas Segner's portrait | |
| Born | 9 October 1704 |
| Died | 5 October 1777 (1777-10-06) (aged 72) |
| Citizenship | Kingdom of Hungary |
| Known for | Segner wheel |
| Scientific career | |
| Fields | Mathematics |
| Institutions | Jena Göttingen Halle |
| Doctoral advisor | Georg Erhard Hamberger Simon Paul Hilscher |
| Doctoral students | Johann Georg Büsch |
Johann Andreas von Segner (Hungarian:Segner János András,German:Johann Andreas von Segner,Slovak:Ján Andrej Segner,Latin:Iohannes Andreas de Segner; October 9, 1704 – October 5, 1777) was aHungarian scientist of German descent. He was born in theKingdom of Hungary, in the former Hungarian capital city of Pozsony, or Pressburg (todayBratislava).
Johann Segner was born to Johann Michael von Segner and his wife Christine von Segner (née Fischer) on probably the 10 October 1704.[2] Other sources mention also the 4 or the 9 October.[2] His father was a tax clerk. His paternal ancestors came fromStyria to Pressburg[3] in theKingdom of Hungary; by the 18th century. In 1596 the family was granted nobility for their military accomplishments byRudolph II.[2] He studied at Pressburg andDebrecen. In April 1725, Segner began studying at theUniversity of Jena.[2] Under the guidance ofGeorg Erhard Hamberger, Segner developed an evidence for thecartesian rule of signs.[2] In his third year at Jena, he began to teach other students in mathematics.[4] During his stay in Jena, he was supported byHermann Friedrich Teichmeyer, who lectured at the faculty of medicine.[5] In October 1729, he graduated under Simon Paul Hirscher from the faculty of medicine.[5] Following he returned to Pressburg where he worked as a medic until December 1731.[5] Following he worked temporarily as the cityphysician in Debrecen until early 1732.[2] In 1732 he returned to Jena where he requested a degree from the faculty of philosophy and also the possibility to give lectures in the faculty of philosophy.[5] He graduated in May 1732 he began to lecture in 1733. In September the same year he was nominated a professor in the faculty of philosophy where he soon lectured the metaphysics ofChristian Wolff.[5]
The University in Göttingen was established after a visit byGeorge II toHanover in 1732.[6] After Hamberger was denied his resignation from the University of Jena, he suggested von Segner instead.[6] 1735 Segner became the professor of mathematics and physics at theUniversity of Göttingen.[6] As in January 1736 the professor for medicine died, he also lectured in the faculty of medicine.[6]
AfterChristian Wolff died, the Prussian KingFriedrich II requested from the mathematicianLeonhard Euler advice on who could be succeed Wolff at theUniversity of Halle.[7] Euler suggestedDaniel Bernoulli who did not accept.[7] Then Euler suggested von Segner, who requested the recognition of his Hungarian title and an extraordinary treatment at the university in return of his acceptance.[7] In 1755 he became a professor at Halle, where he divided the lectures in mathematics and physics withJohann Joachim Lange.[8] In Halle he also established an observatory. Von Segner died on the 5 October 1777.[9]
One of the best-known scientists of his age, Segner was a member of the academies ofBerlin,London, andSaint Petersburg. According toMathematics Genealogy Project,as of February 2013, he has over 66 thousandacademic descendants, out of the total 170 thousand mathematicians in the database.
He was the first scientist to use the reactive force of water and constructed the first water-jet, theSegner wheel, which resembles one type of modernlawn sprinkler. Segner, also produced the first proof ofDescartes' rule of signs. Historians of science remember him as the father of thewater turbine. The lunar craterSegner is named after him, as is asteroid28878 Segner.
In 1732, he married Carolina Sophia, the daughter of Hermann Friedrich Teichmeier.[5] They had three children[5] of which two reached adulthood.[5]
