Augustin-Louis Cauchy

In 1818, Cauchy married Aloise de Bure, member of a family of publishers and booksellers who published majority of his works. The couple had two daughters: Marie Francoise Alicia and Marie Mathilde. Augustin.

Cauchy died on May 23, 1857.

No other mathematician except Leonhard Euler left behind a bigger body of work than Cauchy.

Augustin-Louis Cauchy was born on 21 August 1789 in Paris, France, as the son of Louis Francois Cauchy, a senior French government officer and Marie-Madeleine Desestre. He had two brothers – Alexandre Laurent Cauchy and Eugene Francois Cauchy.

His father lost his job due to the French Revolution and the family moved to Arcueil; Cauchy received his early education there. However, his family returned to Paris after the political atmosphere calmed down.

Cauchy took admission at the best secondary school of Paris, the École Centrale du Panthéon. There he won several prizes in Latin and Humanities.

He chose to opt for engineering and cleared the entrance examination with second rank. He finished his engineering course from Ecole Polytechnique in 1807.

He then attended École des Ponts et Chaussées (School for Bridges and Roads) and completed his graduation in civil engineering.

*Cauchy became a military engineer and accepted a job in Cherbourg in 1810 where he worked on the harbors and fortifications for Napoleon’s English invasion fleet.

Along with his busy engineering career he also managed to prepare three mathematical manuscripts, which he submitted to the Première Classe (First Class) of the Institut de France. Two of these were accepted.

His engineering job, however, did not hold his interest for long. He returned to Paris in 1812, in the hopes of obtaining a mathematical position. Even though he did not resign from his job, he spent the next three years on unpaid sick leave, working on mathematical research.

The 1810s marked a turbulent period in France. In 1815, Napoleon was defeated at Waterloo, and Louis XVIII was installed as the new king. Under his reign the Académie des Sciences was re-established in March 1816 and Cauchy was offered a position there. However his acceptance of the job earned him many enemies.

Over the ensuing years he published many important treatises including ‘Coursd’analyse de l’École Royale Polytechnique’ (1821), ‘Résumé des leçons sur le calcul infinitésimal’ (1823), and ‘Leçons sur les applications du calcul infinitésimal à la géométrie’ (1826–28).

Augustin-Louis Cauchy is best known for single-handedly developing Complex analysis, traditionally known as the theory of functions of a complex variable. This branch of mathematical analysis investigates functions of complex numbers, and is useful in many branches of mathematics, as well as physics.