3 articles
Étale morphism
An étale morphism, or étale map, is a morphism of schemes that is smooth of relative dimension 0, the analog of a local diffeomorphism or covering map in topology.
Flat morphism
A flat morphism is a morphism of schemes whose local ring maps make every local ring of the source a flat module over the target.
Proper morphism
In algebraic geometry, a proper morphism is a morphism of schemes that is separated, of finite type, and universally closed; projective space is proper, while affine space is not.