By the general rules of -categories, a -category is an -category such that
- any -morphism is an equivalence, for ;
- any two parallel -morphisms are equivalent, for .
You can start from any notion of -category, strict or weak; up to equivalence, the result is always the same as a groupoid.
Revised on September 15, 2009 18:57:45
by Urs Schreiber