Galois 

Evariste Galois (1811  1832) is most famous for his contributions to group theory. His work produced a method of determining when a general equation could be solved by radicals, answering the question about the general solution to the quintic equation. This method and the area of mathematics it gave rise to are known as Galois theory.
He also died in a deliberately provoked, politically motivated duel. He was 21, and spent his last night scribbling everything he could think of. In the margins, over and over again he wrote "There is no time!"