Paul Pierre Lévy was a famous mathematician, born 15 September 1886 in Paris into a family of several mathematicians (his grandfather was a professor of mathematics and his father, Lucien Lévy, was an examiner who wrote papers on geometry). He attended the École Polytechnique and as an undergraduate student he published his first paper on semiconvergent series in 1905, at the age of 19. He studied under supervision of the famous mathematician Jacques Hadamard, who had huge influence on his future work. He also worked in military service and studied for three years at the École des Mines. While he studied at the École des Mines he also attended courses at the Sorbonne given by Jean Gaston Darboux and Émile Picard. He attended lectures at the Collège de France by Georges Humbert and Hadamard. He completed his PhD at the Université de Paris in 1911. His doctoral advisors were Jacques Hadamard and Vito Volterra. His thesis on functional analysis was examined by Émile Picard, Poincaré and Hadamard in 1911 and he received his Docteur ès Sciences in 1912. He became a professor at the École des Mines in 1913. In 1920 he was appointed Professor of Analysis at the École Polytechnique, where he stayed until his retirement in 1959. His doctoral students were Wolfgang Doeblin, Michel Loève, Benoît Mandelbrot and Georges Matheron. Lévy received a number of honors. In 1963 he was elected to honorary membership of the London Mathematical Society, and to the French Academy of Sciences (Académie des Sciences). He died on the 15th December 1971.
Lévy made major contributions to probability and functional analysis. He also worked on partial differential equations, generalized differential equations in functional derivatives, series and geometry. In 1926 he extended Laplace transforms to broader function classes. The Lévy flights were introduced by him, which occur, for example, in human traveling behavior/human mobility, also representing an optimal strategy in search processes, etc. Lévy processes, Lévy measures, the Lévy constant (or Khinchin–Lévy constant), the Lévy distribution, the fractal Lévy C curve, etc. are also named after him, which have significant applications in different fields of science.
Trifce Sandev
Radiation Safety Directorate, Skopje, Republic of Macedonia
