Normal not implies strongly potentially characteristic

From Groupprops
The printable version is no longer supported and may have rendering errors. Please update your browser bookmarks and please use the default browser print function instead.

This article gives the statement and possibly, proof, of a non-implication relation between two subgroup properties. That is, it states that every subgroup satisfying the first subgroup property (i.e., normal subgroup) need not satisfy the second subgroup property (i.e., characteristic-potentially characteristic subgroup)
View a complete list of subgroup property non-implications | View a complete list of subgroup property implications
Get more facts about normal subgroup|Get more facts about characteristic-potentially characteristic subgroup

EXPLORE EXAMPLES YOURSELF: View examples of subgroups satisfying property normal subgroup but not characteristic-potentially characteristic subgroup|View examples of subgroups satisfying property normal subgroup and characteristic-potentially characteristic subgroup

Statement

Verbal statement

A normal subgroup need not be characteristic-potentially characteristic.

Statement with symbols

It is possible to have a group K and a normal subgroup H of K such that there is no group G containing K in which both H and K are characteristic subgroups.

Facts used

  1. Characteristic-potentially characteristic implies normal-potentially characteristic
  2. Normal not implies normal-potentially characteristic

Proof

The proof follows directly from facts (1) and (2).