Biographies of Mathematicians - CauchyHis LifeCauchy was born on August 21, 1789 in Paris, France.
Austin Louis Cauchy was born on August 21, 1789 in Paris, France. He was the oldest of six children, born to a Catholic Lawyer, classical scholar, police officer, and strong supporter of the king. With his family, Cauchy's father retreated to the country to escape the gruesome aftermath of the Revolution. For the first twenty years of Cauchy's life he was undernourished, frail, and weak. His father educated him until the age of 13. When Cauchy was young Laplace and Lagrange took part in his mathematical education. Lagrange advised his father to allow his son to have a good knowledge of languages before pursuing mathematics. Between 1802 and 1804 Cauchy attended Ecole Centrale du Pantheon where he studied the classical languages. In 1805 Cauchy took the entrance exam for the Ecole Polytechnique. He was examined by Biot and placed second. There he took courses by Lacroix, de Prony, and Hachette while his analysis teacher was Ampere. After graduating in 1807 Cauchy entered Ecole des Ponts et Chaussees, a engineering school. While he was there he was assigned the Ourcq Canal project under Pierre Girard.
Cauchy took his first job in 1810 at Cherbourg. Here he worked on port facilities for Napoleon's English invasion fleet. While taking a heavy workload Cauchy pursued his mathematical research. In 1811 he proved that the angles of a complex polyhedron are determined by its faces. On this topic Cauchy wrote his first paper and later submitted another paper about polygons and polyhedra. In 1812 Cauchy investigated symmetric functions and submitted a memoir later published in the Ecole Polytechnique in 1815. A memoir on definite integrals was published in 1814, this became the basis of his theory of complex functions.
He was appointed assistant professor of analysis at the Ecole Polytechnique in 1815. The Grand Prix of the French Academy of Science was awarded to him in 1816. Cauchy submitted a paper to the Institute solving one of Fermat's claims on polygonal numbers.
In 1817 Cauchy filled in for Biot at the College de France, where he lectured on the methods of integration. These methods he discovered, but did not publish. Cauchy was the first to make a rigorous study of the conditions of convergence of infinite series in addition to his definition of an integral. Cours d'analyse, text on developing basic theorems of calculus as precisely as possible, was designed for the students at Ecole Polytechnique by Cauchy. He began his study of the calculus of residues in 1826 in Sur un nouveau genre de calcul analogue au calcul infinetesimal while in 1829 in Lecons sur le Calcul Differential he defined for the first time a complex function of a complex variable.
Cauchy was disliked by many of the other scientists. Abel wrote of him after his visit to the Institute in 1826, "Cauchy is mad and there is nothing that can be done about him, although, right now, he is the only one who knows how mathematics should be done." When Cauchy refused to swear an oath of allegiance to the new regime, because of political events in France, he lost all his positions there.
In Turin during 1831 he accepted an offer from the King of Piedmont for a chair of theoretical physics. He taught in Turin and Menbrea attended his courses, he commented, "very confused, skipping suddenly from one idea to another, from one formula to the next, with no attempt to give a connection between them. His presentations were obscure clouds, illuminated from time to time by flashes of pure genius ... of the thirty who enrolled with me, I was the only one to see through it."
In 1833 Cauchy moved from Turin to Prague in order to tutor the grandson of Charles X. As this quote shows he was not very successful, "When questioned by Cauchy on a problem in descriptive geometry, the prince was confused and hesitant ... As with mathematics, the prince showed very little interest ... Cauchy became annoyed and screamed and yelled. The queen sometimes said to him, 'too loud, not so loud'."
There were discussions in Prague with Bolzano about how much Cauchy's definition of continuity is due to Bolanzo. Cauchy's definition was formed before Bolzano's seems to be more convincing, though.
After moving back to Paris in 1838 Cauchy regained his position at the Academy; however, he did not get his teaching positions back because he refused to take the oath. Later in 1839 the position at the Bureau Des Longitudes was open. Although Cauchy was elected, because he did not take the oath he was not allowed to attend any meetings or receive a salary. The mathematics chair at the college de France became vacant in 1843. Cauchy should have easily won on account of his mathematical abilities, but due to religious and political views he was not chosen. During the time after that Cauchy's mathematical output was less than before.
He did important work on applications to mathematical physics, mathematical astronomy, and differential equations. His four volume text Exercises d'analyse et de physique mathemtique was published between 1840 and 1847. Cauchy still did not change in his views and continued to give his colleagues problems. Cauchy stole many of his ideas from his colleagues, they referred to him as "cochon", which is French for pig. In the last few years of his life he had a dispute with Duhamel regarding a result on the inelastic shocks. Cauchy claimed to be the first to give the results in 1832, but Poncelet referred to his own work on the subject in 1826. Even though Cauchy was proved wrong he would never admit it. Cauchy died at about four a.m. on May 27, 1857. His last words were "Men pass away, but their deeds abide". Many terms in mathematics bare his name, the Cauchy integral theorem, in the theory of complex functions, the Cauchy-Kovalevskaya existence theorem for the solution of partial differential equations, the Cauchy-Riemann equations, and the Cauchy sequences. A book of his collected works entitled Oeuvres completes d'Augustin Cauchy (1882-1870) was published in 27 volumes.
Cauchy died on May 23, 1857 in Sceaux, France.
-------
Xem thêm các công trình của cauchy
Click Here
Trang Khác
Click Here
Edited by No Where To Be Seen, 09-09-2006 - 22:04.