Algebraically compact group

In mathematics, in the realm of abelian group theory, a group is said to be algebraically compact if it is a direct summand of every abelian group containing it as a pure subgroup. Equivalent characterizations of algebraic compactness: * The reduced part of the group is Hausdorff and complete in the adic topology. * The group is pure injective, that is, injective with respect to exact sequences where the embedding is as a pure subgroup. Relations with other properties:

Algebraically compact group

In mathematics, in the realm of abelian group theory, a group is said to be algebraically compact if it is a direct summand of every abelian group containing it as a pure subgroup. Equivalent characterizations of algebraic compactness: * The reduced part of the group is Hausdorff and complete in the adic topology. * The group is pure injective, that is, injective with respect to exact sequences where the embedding is as a pure subgroup. Relations with other properties: