Prussian mathematician and physician born in Feldkirch, Austria, known for publishing several trigonometric tables in Wittenberg (1533). Son of a Feldkirch doctor, Georg Iserin and Italian mother Thomasina de Porris, and therefore born Georg Joachim Iserin was educated by his father until the first 14 years of his life, when he was convicted and beheaded for witchcraft. (1528).
Officially obliged to change his name, he became Georg Joachim de Porris who he translated his mother's name from Italian to German von Lauchen, passing to Georg Joachim von Lauchen. Then he added Rheticus in honor of the Roman province of Rhaetia. Achilles Gasser took up medical practice in Feldkirch after his father was executed and helped him continue his studies. He studied at the Latin school in Feldkirch and then went to Zurich where he studied at the Frauenmuensterschule (1528-1531).
He entered the University of Wittenberg (1533) where he received his M.A three years later (1536). Appointed by Philipp Melanchthon, he became professor of mathematics and astronomy at the University of Wittenberg (1536). Two years later Melanchthon appointed him to specialize in astronomy, but his main reason was to visit Copernicus. Departing for Nuremberg (1538) there he visited Johann Schöner who was publishing books, including one that Regiomontanus had intended to publish 60 years earlier.
In Nuremberg he also visited the Petreius printer, met Peter Apianus of Ingolstadt, Joachim Camerarius in Tübingen and on his return to his city, he presented Achilles Gasser with a copy of Sacrobosco. The following year (1539) he traveled to Frauenberg where he studied for two years with Nicolas Copernicus. It was through this disciple that Copernicus came into contact with the trigonometry of Regiomontanus. With the approval of this professor, he published Narratio prima (1540), a pioneering and brief exposition on Copernicus' astronomy, a publication financed by the mayor of Danzig.
With the patronage of Duke Albert of Prussia, he published De Revolutionibus de Copernicus (1541) and returned to the University of Wittenberg and there he was elected Dean of the Faculty of Arts. At the request of the rector of the University of Tübingen and Melanchthon's friend Joachim Camerarius, he was appointed professor of mathematics at the University of Leipzig (1542). He remained in Leipzig until he obtained another license (1545) to study abroad. He was in Italy where he visited Cardano, in Milan. Afterwards he was in Lindau, a Bavarian town on an island in Lake Constance, where he had severe mental problems (1547).
Recovered, he returned to teaching mathematics at Constance for three months while undergoing medical treatment in Zurich, before returning to Leipzig (1548). Still under the influence of Melanchthon, he was made a member of the theological faculty at Leipzig. But a scandal forced him to leave Leipzig (1551): he was accused of homosexual practices with one of his students and had to flee quickly, passing through Chemnitz and Prague. He lost the support of his friends like Melanchthon and was sentenced to 101 years of exile. In Prague (1551-1552) he went on to research medicine employment at the University of Prague, though uninterested in innovations as he did in mathematics.
He rejected an invitation to teach mathematics in Vienna (1553) and moved to Krakov (1554) where he remained for 20 years as a practical general practitioner. In Krakov, he still worked trigonometry, made instruments for astronomy, and made observations and experiments in alchemy, under the patronage of Emperor Maximilian II. Combining the ideas of Regiomontanus, Copernicus, and himself, he wrote the best treatise on trigonometry edited then, the Opus palatinum de triangulis, in two volumes, with tables of all six functions trigonometric. This masterful work was completed and published (1596) by Valentine Otho many years after his death, which occurred in Kassa, today Kosice, Hungary. Otho had studied Wittenberg and did everything possible to visit and meet the so-called master.
Source: http://www.dec.ufcg.edu.br/biografias/
Order R - Biography - Brazil School
