Jacques Tits

Jacques Tits (; 12 August 1930 – 5 December 2021) was a Belgium-born French mathematician. He worked on group theory and incidence geometry. He introduced Tits buildings, the Tits alternative, and the Tits group.
In 2008 he was awarded the Abel Prize, along with John Griggs Thompson, “for their profound achievements in algebra and in particular for shaping modern group theory.”
Tits died on 5 December 2021 at the age of 91.