pullbackkiinnittyjät
Pullbackkiinnittyjät is a concept in category theory describing a class of subobjects that remains stable under pullback. The idea is to formalize when a collection of subobjects behaves well when changing the base object along a morphism.
Formally, let C be a category with pullbacks. A class P of monomorphisms (subobjects) in C is
Examples help illustrate the notion. In the category of sets, subobjects are just subsets, and the pullback
Applications of pullbackkiinnittyjät appear in descent theory and sheaf theory, where stability under base change (pullback)