Abnormal subgroup

In group theory, an **abnormal subgroup** is a specific type of subgroup that captures certain properties related to the structure of the group. A subgroup \( H \) of a group \( G \) is called **abnormal** if it satisfies the following condition: For every \( g \in G \), if \( gH \) (the left coset of \( H \) in \( G \)) intersects with \( H \) non-trivially (i.e.