Andrey Kolmogorov

Andrey Nikolaevich Kolmogorov was born on 25 April 1903 in Russia, entering a century he would help define mathematically. A Soviet mathematician, he built the axiomatic foundations of modern probability theory, turning a field of intuitions into something you could prove. But probability was just one continent: he carved through topology, intuitionistic logic, turbulence, classical mechanics, functional analysis, algorithmic information theory, and computational complexity, each time leaving structure where there had been questions. He died on 20 October 1987, having spent eight decades making the mathematics of uncertainty certain.