Complex analysis cartan

Élie Joseph Cartan was an influential French mathematician who did fundamental work in the theory of Lie groups, differential systems, and differential geometry.
He also made significant contributions to general relativity and indirectly to quantum mechanics.
He is widely regarded as one of the greatest mathematicians of the twentieth century.

Henri Paul Cartan was a French mathematician who made substantial contributions to algebraic topology.

In mathematical analysis, a thin set is a subset of n-dimensional complex space Cn with the property that each point has a neighbourhood on which some non-zero holomorphic function vanishes.
Since the set on which a holomorphic function vanishes is closed and has empty interior, a thin set is nowhere dense, and the closure of a thin set is also thin.