Center-fixing automorphism-balanced subgroup

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This page describes a subgroup property obtained as a conjunction (AND) of two (or more) more fundamental subgroup properties: center-fixing automorphism-invariant subgroup and subgroup whose center is contained in the center of the whole group
View other subgroup property conjunctions | view all subgroup properties

Definition

The following are equivalent definitions of center-fixing automorphism-balanced subgroup.

No. Shorthand A subgroup of a group is termed a center-fixing automorphism-balanced subgroup if ... A subgroup H of a group G is termed a center-fixing automorphism-balanced subgroup if ...
1 center-fixing automorphism-invariant, and center contained in group's center it is a center-fixing automorphism-invariant subgroup of the whole group, and its center is contained in the center of the whole group. H is invariant under any automorphism σ of G with the property that σ(x)=x for all xZ(G), and additionally, Z(H)Z(G). Here Z(H) and Z(G) denote respectively the centers of H and G.
2 center-fixing automorphism restricts to center-fixing automorphism any center-fixing automorphism of the whole group restricts to a center-fixing automorphism of the subgroup. For any automorphism σ of G with the property that σ(x)=x for all xZ(G), we have that σ(H)H, and also that σ(x)=x for all xZ(H).

Relation with other properties

Weaker properties

Property Meaning Proof of implication Proof of strictness (reverse implication failure) Intermediate notions
center-fixing automorphism-invariant subgroup
normal subgroup whose center is contained in the center of the whole group its center is contained in the whole group's center. |FULL LIST, MORE INFO
normal subgroup every inner automorphism sends the subgroup to itself |FULL LIST, MORE INFO
subgroup whose center is contained in the center of the whole group its center is contained in the whole group's center. |FULL LIST, MORE INFO