Unlike many of the other groups associated with a topological space, the fundamental group need not be Abelian. An example of a space with a non-Abelian fundamental group is the complement of a [trefoil knot]? in R3. |
Unlike many of the other groups associated with a topological space, the fundamental group need not be Abelian. In fact, every group is isomorphic to the fundamental group of some topological space. An example of a space with a non-Abelian fundamental group is the complement of a [trefoil knot]? in R3. |