Arnold Droz-Farny (12 February 1856 – 14 January 1912) was a Swiss

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History On ...

, professor in High School of Porrentruy (near

Basel , french: link=no, Bâlois(e), it, Basilese , neighboring_municipalities= Allschwil (BL), Hégenheim (FR-68), Binningen (BL), Birsfelden (BL), Bottmingen (BL), Huningue (FR-68), Münchenstein (BL), Muttenz (BL), Reinach (BL), Riehen (BS ...

Life and work

Arnold Droz changed his family name later in his life when he married Lisa Farny. He studied in the high school of

Neuchâtel , neighboring_municipalities= Auvernier, Boudry, Chabrey (VD), Colombier, Cressier, Cudrefin (VD), Delley-Portalban (FR), Enges, Fenin-Vilars-Saules, Hauterive, Saint-Blaise, Savagnier , twintowns = Aarau (Switzerland), Besançon (France), ...

and then in the Technical School of Stuttgart and in the

university of Munich The Ludwig Maximilian University of Munich (simply University of Munich or LMU; german: Ludwig-Maximilians-Universität München) is a public research university in Munich, Germany. It is Germany's List of universities in Germany, sixth-oldest u ...

. After graduating in mathematics in Munich, he began to teach in a private school. Soon, in 1880, he was appointed to the chair of mathematics in the Lycée Cantonal of

Porrentruy Porrentruy (, fc, Poérreintru , german: Pruntrut) is a Swiss municipality and seat of the district of the same name located in the canton of Jura. Porrentruy is home to National League team, HC Ajoie. History The first trace of human pre ...

, where he remained till 1908 when his ill health forced him to retire. In mathematical world he is known by a theorem, the

Droz-Farny line theorem In Euclidean geometry, the Droz-Farny line theorem is a property of two perpendicular lines through the orthocenter of an arbitrary triangle. Let T be a triangle with vertices A, B, and C, and let H be its orthocenter (the common point of its thr ...

, stated by him in 1899, without proof, in an answer to question 14111 in the journal ''The Educational Times''. Droz-Farny was also an amateur numismatic collector who published some articles on historical remarks of some coins and, after his death, he donated his collection to the cantonal authorities.

References

Bibliography

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External links

* {{DEFAULTSORT:Droz Farny, Arnold 19th-century Swiss mathematicians 20th-century Swiss mathematicians 1856 births 1912 deaths