Gabriel Cramer

Gabriel Cramer

Gabriel Cramer (born July 31, 1704 in Geneva , † January 4, 1752 in Bagnols-sur-Cèze , France ) was a Geneva mathematician .

Life

Title page of the book Introduction à l'analyse de lignes courbes algébriques

Cramer was a son of the doctor Jean Isaac Cramer. He still had two brothers. In 1722 he received his doctorate in Geneva for his work in the field of acoustics . In 1724 he became a professor of mathematics at the Geneva Academy . Here he suggested that the lectures not only be given in Latin - as was customary at the time - but also in French . On several trips from 1727 to 1729 he met with leading mathematicians of his time:

• in Basel with Johann I Bernoulli and Leonhard Euler ,
• in England with Edmond Halley , Abraham de Moivre , James Stirling and others,
• in suffering with 'sGravesande,
• in Paris with Bernard le Bovier de Fontenelle , Pierre-Louis Moreau de Maupertuis , Georges-Louis Leclerc de Buffon and Alexis-Claude Clairaut .

These meetings and subsequent correspondence influenced his work.

In 1750 he published the book "Introduction à l'analyse des lignes courbes algébriques". In one of the appendices, a formula for solving systems of linear equations appears , known as Cramer's rule . This gave the impetus for the development of the determinant theory .

In addition, he wrote works on legal and state philosophy and on the history of mathematics. In addition to his work as a professor, he held public offices, took part in his government's military and armaments projects, was a consultant for repair work on churches and researched church archives.

Since 1746 he was a foreign member of the Prussian Academy of Sciences . In 1749 he was elected a member ( Fellow ) of the Royal Society .

Works

• Source est the cause de la figure elliptique des planètes et de la mobilité de leur aphélies? Geneva 1730.
  (He submitted this work to the Paris Academy. It received 2nd prize (1st prize went to Johann I Bernoulli ).)
• Introduction to the analysis of the lignes courbes algébriques. Geneva 1750.
  (Here he examines algebraic curves; Cramer's rule named after him appears in Appendix 1, but without proof.)
• Publication of the work Opera Omnia by Johann Bernoulli. 1742, 4 volumes.
• Publication of Works by Jakob Bernoulli. 1744, 2 volumes.
  (All works by Jakob I Bernoulli are included, with the exception of Ars conjectandi .)
• Publication (together with Johann Castillon ) of the correspondence between Johann Bernoulli and Gottfried Wilhelm Leibniz . 1745.

Individual evidence

1. ^ Jean-Luc Chabert et al .: A History of Algorithms. Form the pebble to the microchip. Springer-Verlag, 1999, ISBN 3-540-63369-3 , p. 287
2. ^ Members of the previous academies. Gabriel Cramer. Berlin-Brandenburg Academy of Sciences and Humanities , accessed on March 10, 2015 . 

Web links

Commons : Gabriel Cramer  - collection of pictures, videos and audio files

Commons : Some pages of the book “Introduction à l'analyse des lignes courbes algébriques”  - collection of images, videos and audio files

• John J. O'Connor, Edmund F. Robertson :  Gabriel Cramer. In: MacTutor History of Mathematics archive .
• Entry for Cramer, Gabriel (1704-1752) in the Archives of the Royal Society , London
• Strodtmann, Johann Christoph, story of Mr. Gabriel Cramer . In The New Learned Europe […] . 4th part, Meissner, 1754. Digitization: e-rara.ch
• Laurence-Isaline Stahl-Gretsch: Rousseau et les Savants Genevois. Musée d'histoire des sciences de la Ville de Genève (2012) pp. 29–31, accessed online August 17, 2012 (PDF; 3.9 MB)
• Spektrum.de: Gabriel Cramer (1704–1752): A true networker January 1, 2019