Jørgen Mohr (Latinised Georg(ius) Mohr; 1 April 1640 – 26 January 1697)[1] was a Danishmathematician, known for being the first to prove the Mohr–Mascheroni theorem, which states that any geometric construction which can be done with compass and straightedge can also be done with compasses alone.
Biographyedit
Mohr was born in Copenhagen, the son of a tradesman named David Mohrendal.[1] Beginning in 1662 he traveled to the Netherlands, to study mathematics with Christiaan Huygens.[1][2] In 1672 he published his first book, Euclides Danicus, simultaneously in Copenhagen and Amsterdam, in Danish and Dutch respectively. This book, proving the Mohr–Mascheroni theorem 125 years earlier than Lorenzo Mascheroni, would languish in obscurity until its rediscovery in 1928.[3] Mohr served in Franco-Dutch War in 1672–1673, and was taken prisoner by the French.[1][2] By 1673, he had published his second book, Compendium Euclidis Curiosi.[2] A third book was later mentioned by Mohr's son; for many years this was believed to be the Gegenübung auf Compendium Euclidis Curiosi but Andersen & Meyer (1985) argue that it must be a different book, and that the Gegenübung has a different author.[1][4] As well as his work on geometry, Mohr contributed to the theory of nested radicals, with the aim of simplifying Cardano's formula for the roots of a cubic polynomial.[4]
While in the Netherlands, Mohr became a friend of Ehrenfried Walther von Tschirnhaus. The two visited Gottfried Wilhelm Leibniz in France and John Collins in England together. Mohr returned to Denmark in 1681; he had dedicated Euclides Danicus to Christian V and hoped for a position in exchange, but was offered only a position as a shipyard supervisor, which he declined. He married Elizabeth von der Linde of Copenhagen on 19 July 1687, and soon after returned to Holland; their son, Peter Georg Mohrenthal, eventually settled in Dresden as a bookseller and publisher.[2][5] In 1695 he took a job with Tschirnhaus,[2] and spent his last few years as a guest in Tschirnhaus's house. He died in Kieslingswalde near Görlitz, Germany.[1]
^ abcdeAndersen, Kirsti (1980), "An Impression of Mathematics in Denmark in the Period 1600–1800", Centaurus, 24 (1): 316–334, Bibcode:1980Cent...24..316A, doi:10.1111/j.1600-0498.1980.tb00381.x.
^Alexanderson, Gerald L. (July 2014), "About the cover: Two theorems on geometric constructions", Bulletin of the American Mathematical Society, 51 (3): 463–467, doi:10.1090/S0273-0979-2014-01458-2.
^ abAndersen, Kirsti; Meyer, Henrik (1985), "Georg Mohr's three books and the Gegenübung auf Compendium Euclidis Curiosi", Centaurus, 28 (2): 139–144, Bibcode:1985Cent...28..139A, doi:10.1111/j.1600-0498.1985.tb00833.x, MR 0825846.
^Sarton, George (1936), "Euclides danicus, Amsterdam 1672 by Georg Mohr; Johannes Hjelmslev; Beiträge zur Lebensbeschreibung von Georg Mohr (1640-1697) by Johannes Hjelmslev", Isis, 26 (1): 167–170, doi:10.1086/347140, JSTOR 225067.
^Official website for the Georg Mohr-Competition (in Danish), retrieved 27 June 2014.
Further readingedit
Westfall, Richard S. (1995), Mohr, Georg, The Galileo Project
"Mohr, Georg", Complete Dictionary of Scientific Biography, 2008.
January 01, 1970
georg, mohr, chess, player, chess, player, jørgen, mohr, latinised, georg, mohr, april, 1640, january, 1697, danish, mathematician, known, being, first, prove, mohr, mascheroni, theorem, which, states, that, geometric, construction, which, done, with, compass,. For the chess player see Georg Mohr chess player Jorgen Mohr Latinised Georg ius Mohr 1 April 1640 26 January 1697 1 was a Danish mathematician known for being the first to prove the Mohr Mascheroni theorem which states that any geometric construction which can be done with compass and straightedge can also be done with compasses alone Biography editMohr was born in Copenhagen the son of a tradesman named David Mohrendal 1 Beginning in 1662 he traveled to the Netherlands to study mathematics with Christiaan Huygens 1 2 In 1672 he published his first book Euclides Danicus simultaneously in Copenhagen and Amsterdam in Danish and Dutch respectively This book proving the Mohr Mascheroni theorem 125 years earlier than Lorenzo Mascheroni would languish in obscurity until its rediscovery in 1928 3 Mohr served in Franco Dutch War in 1672 1673 and was taken prisoner by the French 1 2 By 1673 he had published his second book Compendium Euclidis Curiosi 2 A third book was later mentioned by Mohr s son for many years this was believed to be the Gegenubung auf Compendium Euclidis Curiosi but Andersen amp Meyer 1985 argue that it must be a different book and that the Gegenubung has a different author 1 4 As well as his work on geometry Mohr contributed to the theory of nested radicals with the aim of simplifying Cardano s formula for the roots of a cubic polynomial 4 While in the Netherlands Mohr became a friend of Ehrenfried Walther von Tschirnhaus The two visited Gottfried Wilhelm Leibniz in France and John Collins in England together Mohr returned to Denmark in 1681 he had dedicated Euclides Danicus to Christian V and hoped for a position in exchange but was offered only a position as a shipyard supervisor which he declined He married Elizabeth von der Linde of Copenhagen on 19 July 1687 and soon after returned to Holland their son Peter Georg Mohrenthal eventually settled in Dresden as a bookseller and publisher 2 5 In 1695 he took a job with Tschirnhaus 2 and spent his last few years as a guest in Tschirnhaus s house He died in Kieslingswalde near Gorlitz Germany 1 The Georg Mohr competition which is used to select Danish participants to the International Mathematical Olympiad is named after Mohr 6 References edit a b c d e f O Connor John J Robertson Edmund F Georg Mohr MacTutor History of Mathematics Archive University of St Andrews a b c d e Andersen Kirsti 1980 An Impression of Mathematics in Denmark in the Period 1600 1800 Centaurus 24 1 316 334 Bibcode 1980Cent 24 316A doi 10 1111 j 1600 0498 1980 tb00381 x Alexanderson Gerald L July 2014 About the cover Two theorems on geometric constructions Bulletin of the American Mathematical Society 51 3 463 467 doi 10 1090 S0273 0979 2014 01458 2 a b Andersen Kirsti Meyer Henrik 1985 Georg Mohr s three books and the Gegenubung auf Compendium Euclidis Curiosi Centaurus 28 2 139 144 Bibcode 1985Cent 28 139A doi 10 1111 j 1600 0498 1985 tb00833 x MR 0825846 Sarton George 1936 Euclides danicus Amsterdam 1672 by Georg Mohr Johannes Hjelmslev Beitrage zur Lebensbeschreibung von Georg Mohr 1640 1697 by Johannes Hjelmslev Isis 26 1 167 170 doi 10 1086 347140 JSTOR 225067 Official website for the Georg Mohr Competition in Danish retrieved 27 June 2014 Further reading editWestfall Richard S 1995 Mohr Georg The Galileo Project Mohr Georg Complete Dictionary of Scientific Biography 2008 Retrieved from https en wikipedia org w index php title Georg Mohr amp oldid 1084715629, wikipedia, wiki, book, books, library,
