nLab
n-group

An n-group is a group object internal to n-groupoids.

If it is deloopable, an n-group G is the hom-object G=Aut BG(*) of an n-groupoid BG with a single object *.

If BG is a strict n-groupoid, then the corresponding n-group is called strict. Strict n-groups are equivalent to crossed complexes of groups, of length n.

Under the homotopy hypothesis n-groups correspond to (pointed) connected homotopy n-types.

See also