Mathwar/Personlist/Borel Emile
Emile Borel
(* January 7th 1871 in Saint Affrique, France, † February 3rd 1956 in Paris, France)
Along with René-Louis Baire and Henri Lebesgue, he was among the pioneers of measure theory and its application to probability theory. The concept of a Borel set is named in his honor. One of his books on probability introduced the amusing thought experiment that entered popular culture under the name infinite monkey theorem or the like. He also published a number of research papers on game theory.
Life
While studying at university he undertook military service with the engineers at Montpellier for a while but he seemed to be able to do this without too much disruption to his mathematical work. He published his first two mathematical papers in 1890. These were fairly minor works but still remarkable for a young undergraduate student just starting his studies.
At almost exactly the same time that he was receiving his doctorate, when still only 22 years of age, Borel was appointed Maître de Conférence at the University of Lille. He spent three years at Lille during which time he published 22 papers, with several others in the hands of the printer when he left. It was not only the quantity that is amazing but also the remarkable quality of the work that he produced. He returned to Paris in January 1897 when appointed Maître de Conférence at the École Normale Supérieure. Later in 1897 he was joint secretary at the first International Congress of Mathematicians held in Zurich from 9 August to 11 August.
Borel achieved much over the next years, both in his career and in the outstanding mathematics which he produced. From 1899 to 1902 he taught at the Collège de France and was reserve for the Cours Peccot. He was appointed examiner for entry to the École Navale in 1900, holding this position for ten years. He was awarded the Grand Prix of the Academy of Sciences in 1898, he was awarded the Poncelet Prize in 1901, he received the Vaillant Prize in 1904, and the Petit d'Ormcy Prize in 1905. Also in 1905 he was elected president of the French Mathematical Society.
In October 1901 he had married Marguerite Appell, daughter of the mathematician Paul Appell. They had no children but adopted one of Borel's nephews, Fernand Lebeau, the son of his eldest sister who he had lived with while a pupil at the Lycée at Montauben. Both his sister and her pastor husband had died young and, tragically, Fernand was later killed during World War I. Marguerite Borel was an outstanding author, writing under the pen name Camille Marbo (Marbo being the first three letters of Marguerite and the first two of Borel), and received the distinction of being awarded the Prix Femina in 1913 for La Statue voilée.
In 1909 Borel was appointed to a chair of Theory of Functions created specially for him at the Sorbonne and he went on to hold this professorship until 1941.