IN NOVEMBER 2002, an obscure Russian mathematician named Grigori Perelman caused a sensation in the mathematical community when he posted the first in a series of papers proving the most famous unsolved problem in topology: the . He caused another sensation when he was awarded the – the “mathematics Nobel” – for his work, declined to accept it, and then left mathematics altogether. When last heard of, he was living a reclusive existence at his mother’s home in St Petersburg.
In Perfect Rigor, Masha Gessen sets out to unravel the mystery of : what is it that has set him…