# Charles Ehresmann

**Charles Ehresmann** (1905-1979) was a French mathematician who worked on differential topology and category theory. He is known for work on the topology of Lie groups, the *jet* concept (see jet bundle), and his seminar on category theory.
He attended the École Normale Supérieure in Paris before performing a years military service.

In 1957 he founded the mathematical journal *Cahiers de Topologie et Géometrie Différentielle Categoriques*.

Dieudonné describes Ehresmann's personality as "*... distinguished by forthrightness, simplicity, and total absence of conceit or careerism. As a teacher he was outstanding, not so much for the brilliance of his lectures as for the inspiration and tireless guidance he generously gave to his research students ... *"

## See also

## External link

- O'Connor, John J., and Edmund F. Robertson. "Charles Ehresmann".
*MacTutor History of Mathematics archive*.