Galois — A Genius Lost at Twenty

Évariste Galois was born in 1811 and died in a duel aged 20 — but in the night before that duel he wrote out, feverishly, a mathematics that would take decades to understand. He had proved why equations of degree 5 and higher cannot be solved by radicals — something mathematicians had sought for 300 years. He invented what we now call group theory to do it. His manuscripts contain the remark: 'I have not time.' Modern algebra was born in that single sleepless night.