21 citations · 86 across the 22 of their papers we have counts for
4 papers · 2 filters
A retraction theorem for topological fundamental groups with application to the Hawaiian earring
Paul Fabel
A characterization of regular topological fundamental groups yields a `no retraction theorem' for spaces constructed in similar fashion to the Hawaiian earring.
Topological fundamental groups can distinguish spaces with isomorphic homotopy groups
Paul Fabel
We exhibit a map f between aspherical spaces X and Y such that f induces an isomorphism on homotopy groups but, with natural topologies, X and Y fail to have homeomorphic fundament…
A monomorphism theorem for the inverse limit of nested retracts
Paul Fabel
Various characterizations are offered of injectivity of the canonical fundamental group homomorphism for a certain class of inverse limit spaces. One application characterizes the…
The fundamental group of the harmonic archipelago
Paul Fabel
The harmonic archipelago HA is obtained by attaching a large pinched annulus to every pair of consecutive loops of the Hawaiian earring. We clarify the fundamental group pi1(HA) as…