Grothendieck's 80th birthday

Today's the 80th birthday of Alexander Grothendieck. He is usually considered one of the greatest mathematicians of the 20th century. It's hardly an exaggeration that almost all modern algebraic geometers are influenced by his work (in particular, his famous EGA and SGA books). He is also quite a remarkable character: he withdrew from mathematics at the age of 42, and in 1991, he even left his home and disappeared. He is now said to live in southern France or Andorra and to entertain no visitors. Though he has been inactive in mathematics for many years, he remains one of the greatest and most influential mathematicians of modern times. Find out more about him in the following wiki article!