Andrey Markov

Andrey Andreyevich Markov (June 14, 1856 - July 20, 1922) was a Russian mathematician celebrated for his pioneering work in stochastic processes. He extended fundamental theorems, including the law of large numbers and the central limit theorem, to sequences of dependent random variables, establishing the foundation for what are now called Markov chains. His most famous application involved analyzing the distribution of vowels and consonants in Alexander Pushkin's novel in verse Eugene Onegin, treating the text as a sequence of abstract categories to demonstrate that chains of dependent events could be rigorously modeled, producing the first empirical example of a Markov chain. He also collaborated with his younger brother Vladimir on the Markov brothers' inequality, and his son continued his mathematical legacy in constructive mathematics and recursive function theory.