closed immersion
A morphism of schemes is a closed immersion if:
- 1.
As a map of topological spaces

, is a homeomorphism from into a closed subset of , and
- 2.
the morphism of sheaves associated with is an epimorphism

(http://planetmath.org/AbelianCategory) in the category of sheaves.
This notion is the analog of the notion of closed immersion (http://planetmath.org/Immersion) in the category![]()
of differential manifolds.