Nikolai Durov is a Russian programmer and mathematician. He is the elder brother of Pavel Durov, with whom he founded the social networking site VK and later Telegram.
Durov introduced commutative algebraic monads as a generalization of local objects in a generalized algebraic geometry. Versions of a tropical geometry, of an absolute geometry over a field with one element and an algebraic analogue of Arakelov geometry were realized in this setup.