Relatively rigid subgroup
This article defines a subgroup property: a property that can be evaluated to true/false given a group and a subgroup thereof, invariant under subgroup equivalence. View a complete list of subgroup properties[SHOW MORE]
Definition
A subgroup of a group is termed a relatively rigid subgroup if any automorphism of the subgroup that extends to an automorphism of the whole group, must be an inner automorphism of the subgroup.