On the failure of the first Cech homotopy group to register geometrically relevant fundamental group elements
Abstract
We construct a space P for which the canonical homomorphism π1(P,p) → π1(P,p) from the fundamental group to the first Cech homotopy group is not injective, although it has all of the following properties: (1) P\p\ is a 2-manifold with connected non-compact boundary; (2) P is connected and locally path connected; (3) P is strongly homotopically Hausdorff; (4) P is homotopically path Hausdorff; (5) P is 1-UV0; (6) P admits a simply connected generalized covering space with monodromies between fibers that have discrete graphs; (7) π1(P,p) naturally injects into the inverse limit of finitely generated free monoids otherwise associated with the Hawaiian Earring; (8) π1(P,p) is locally free.
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