nLab
essentially affine category

A category is essentially affine if its change of base functors for its fibration of points are equivalences of categories. An essentially affine category is both protomodular and Mal'cev. Every subobject is normal.

Borceux and Bourn liken an essentially affine category to a non-pointed abelian category (see Borceux-Bourn).

Example

  • The category of abelian extensions of an arbitrary group GG.

Created on October 16, 2014 at 14:53:16. See the history of this page for a list of all contributions to it.