## Mathematicians Of The Day

### 29th April

On this day in 1901, Lebesgue published his famous paper

*Sur une généralisation de l'intégrale définie*in the*Comptes Rendus*of the French Academy of Sciences. In this he gave the definition of the Lebesgue integral that generalises the notion of the Riemann integral by extending the concept of the area below a curve to include many discontinuous functions.
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##### Born:

- 1850: William Story Ⓟ
- 1854: Henri Poincaré Ⓟ
- 1872: Forest Ray Moulton Ⓟ
- 1876: Paul Montel Ⓟ
- 1886: Walter Brown
- 1930: Wang Yuan Ⓟ
- 1936: Volker Strassen Ⓟ

##### Died:

- 1864: Charles-Julien Brianchon
- 1872: Jean-Marie Duhamel Ⓟ
- 1916: Jorgen Gram Ⓟ
- 1951: Ludwig Wittgenstein Ⓟ
- 1970: Paul Finsler Ⓟ
- 1975: Joseph Burchnall Ⓟ
- 1981: Félix Pollaczek Ⓟ
- 2012: Joram Lindenstrauss Ⓟ
- 2014: Manuel Valdivia Ⓟ
- 2022: Georgia Benkart Ⓟ

#### Quotation of the day

##### From Henri Poincaré

When one tries to depict the figure formed by these two curves and their infinity of intersections, each of which corresponds to a doubly asymptotic solution, these intersections form a kind of net, web or infinitely tight mesh . . . . One is struck by the complexity of this figure that I am not even attempting to draw.