Léopold Leau (1868-1943) was a French

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, mathematical structure, structure, space, Mathematica ...

, primarily known for his ties to

international auxiliary language An international auxiliary language (sometimes acronymized as IAL or contracted as auxlang) is a language meant for communication between people from different nations, who do not share a common first language. An auxiliary language is primarily a ...

s. The

Delegation for the Adoption of an International Auxiliary Language The Delegation for the Adoption of an International Auxiliary Language () was a body of academics convened in the early part of the 1900s (decade) to decide on the issue of which international auxiliary language should be chosen for international u ...

was founded on 7 January 1901 on Leau's initiative. He co-wrote with Prof.

Louis Couturat Louis Couturat (; 17 January 1868 – 3 August 1914) was a French logician, mathematician, philosopher, and linguist. Couturat was a pioneer of the constructed language Ido. Life and education Born in Paris. In 1887 he entered École Normale S ...

the monumental ''Histoire de la Langue Universelle'' (1903) and its supplement ''Les Nouvelles Langues Internationales'' (1907). Leau studied at the École normal supérieure in Paris and received his doctorate there in April 1897.Die Dissertation ''Étude sur les équations fonctionnelles à une ou à plusieurs variables'' erschien in: Annales de la Faculté des Sciences de Toulouse: Mathématiques, Série 1, Band 11 (1897), Heft 2, Seiten E.1-E.110. Digitalisat bei Numdam
Teil 1Teil 2
/ref> Later he was a professor at the University of Nancy . There he was Dean of the Faculté des Sciences from 1931–34. In his dissertation, Leau examined, among other things, the iteration behavior of holomorphic functions in the environment of a rationally indifferent fixed point. His results are known today under the name (Leau- Fatou) Flower Theorem . They play an important role in the

complex dynamics Complex dynamics, or holomorphic dynamics, is the study of dynamical systems obtained by Iterated function, iterating a complex analytic mapping. This article focuses on the case of algebraic dynamics, where a polynomial or rational function is it ...

References

* Daniel S. Alexander: A history of complex dynamics: from Schröder to Fatou and Julia. (Aspects of Mathematics), Vieweg, Braunschweig 1994, . Chapter 5 describes Leau's contributions. Constructed language creators Linguists from France 19th-century French mathematicians 20th-century French mathematicians 1868 births 1943 deaths {{France-mathematician-stub