After studying at the École normale supérieure, this brilliant mathematician became a professor at the University of Caen, where he spent his entire career. He conducted remarkable research in set theory and group theory, becoming a specialist in what are known as ordered braids in the latter field. He was also actively involved in the CNRS’s Institut national des sciences mathématiques et de leurs interactions.
Eager to bring mathematics to a wider audience in entertaining ways (see Tangente 129, 2009), Patrick Dehornoy created several videos about set theory. He even produced a film, Le Paradis des mathématiciens (Mathematicians’ Paradise), in collaboration with the Institut Henri-Poincaré (7 min, 2016). In it, he imagines himself in this paradise, amused to see Cédric Villani drawing inspiration from one of his books, Ordering Braids. Patrick Dehornoy may now be there, in paradise, while Cédric Villani seems rather busy with other projects at the moment…
