(The most amazing thing I just found out is he probably wrote his math articles inside his closet, haha..)

This october is the 30th anniv. of his death. Hey, I personally also have a book written by him: Real and Functional Analysis(translated into english)

--Son of a bolshevik martyr

--A short account of his most important early work. During the 1920s,the french mathematician Lebesgue constructed a new revolutionary concept of integration: Lebesque Measure and integration(named after him) which gives new meaning to area, volume... Kolmogorov seized the idea immediately and applied it to probability, hence the term 'probability measure' which also axiomatised probability. All the more advanced texts on probability followed Kolmogorov's formulation.

(I posed this before here: On earth human associate basic area with that of a rectangle,ie width x height. Could circle be used as basic unit of area instead?)

https://en.wikipedia.org/wiki/Andrey_Kolmogorov