On noncontractible compacta with trivial homology and homotopy groups
Abstract
We construct an example of a Peano continuum X such that: (i) X is a one-point compactification of a polyhedron; (ii) X is weakly homotopy equivalent to a point (i.e. πn(X) is trivial for all n ≥ 0); (iii) X is noncontractible; and (iv) X is homologically and cohomologically locally connected (i.e. X is a HLC and clc space). We also prove that all classical homology groups (singular, Cech, and Borel-Moore), all classical cohomology groups (singular and Cech), and all finite-dimensional Hawaiian groups of X are trivial.
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