Charles Hermite

In 1848, Hermite married Louise Pauline Arsène Bertrand, sister of fellow mathematician Joseph Louis François Bertrand. Together, they had two daughters, Isabelle Caroline Ferdinande Forestier nee Hermite and Marie Picard nee Hermite.

In 1856, Hermite contracted small pox. During this ailment, Augustin-Louis Cauchy provided him a strong moral support. Under his influence, Hermite returned to Roman Catholic fold and became royalist, a belief he held until the very end.

Hermite officially retired from work in 1897. He died around three years later on 14 January 1901 in Paris, at the age of 78.

Charles Hermite was born on December 22, 1822 in Dieuze, located in the north-eastern France. His father, Ferdinand Hermite, was an engineer by education, but an artist by inclination. Before his marriage to Madeleine nee Lalleman, he briefly worked in a salt pit, later looking after his in-law’s draping business.

Ferdinand and Madelein had seven children, out of which Charles was born sixth. He had four brother and two sisters. Charles was born with a defect in his right foot, which hampered his movement. The deformity greatly worried his parents because they knew it would get in the way of his career later in life. But having a happy disposition, Charles bore it quite cheerfully.

In 1828, when Charles’ family relocated to Nancy. Although his parents did not take much interest in their children’s education they sent all of them to good schools; Charles was admitted to Collège de Nancy.

After graduating from Collège de Nancy, Charles Hermite moved to Paris, where he initially studied at Lycee Henri IV. Here, he studied physics with César-Mansuète Despretz and was greatly influenced by him. However, he did not continue here for long, moving to Lycée Louis-le-Grand in 1840.

At Lycée Louis-le-Grand, he studied mathematics with Louis Richard, who years ago had taught Évariste Galois. Although he had entered the institution with the intention of preparing himself for the entrance examination at École Polytechnique very soon his attention began to dither.

In 1848, Charles Hermite began his career as répétiteur and examinateur d'admission at École Polytechnique, the same institution he was asked to leave six years ago. In the same year, he proved that doubly periodic functions can be represented as quotients of periodic entire functions.

In 1849, he submitted a memoir to the Académie des Sciences, in which he applied the residue techniques discovered by Augustin-Louis Cauchy to doubly periodic functions. While both Cauchy and Charles-François Sturm gave good report, it could not be published because of a priority dispute with Liouville.

From early 1850s, Hermite started working on the theory of quadratic forms, for which he had to study invariant theory. While doing so, he discovered a reciprocity law concerning binary forms, finally creating theory of transformations in 1855. In the same year, he published 'Sur quelques applications des fonctions elliptiques'.

In 1858, he showed that one could solve an algebraic equation of the fifth degree by using elliptic functions. It is one of his most important works, making him rightly famous.

In 1862, École Polytechnique created the position of maître de conference especially for him, appointing him to the post. In 1863, he was appointed an examinateur de sortie et de classement there. Also from 1862 to 1873 he was lecturer at the École Normale Supérieure.

Charles Hermite is most famous for his 1858 work on algebraic equation of the fifth degree. Although such equations cannot be solved in radicals, he showed that it could solved by using elliptic functions, creating a new branch of algebra. Later he applied the results to class number relations of quadric forms.