Homology of Deleted Product Spaces.
Homology with models
Homotopy and homology groups of the n-dimensional Hawaiian earring
For the n-dimensional Hawaiian earring n ≥ 2, and is trivial for each 1 ≤ i ≤ n - 1. Let CX be the cone over a space X and CX ∨ CY be the one-point union with two points of the base spaces X and Y being identified to a point. Then for n ≥ 1.
Homotopy and homology in pretopological spaces
Homotopy colimits and cohomology with local coefficients
Idempotent Topological Groupoids with Non-Empty Center.
Isomorphic cohomology Yields isomorphic homology.
Koszul duality and equivariant cohomology.
Low dimensional homotopy groups of suspensions of the Hawaiian earring
We study the (n+1)st homotopy groups and the shape groups of the (n-1)-fold reduced and unreduced suspensions of the Hawaiian earring.
Normalisation for the fundamental crossed complex of a simplicial set.
On a multiplicativity up to homotopy of the Gugenheim map.
On the first homology of Peano continua
We show that the first homology group of a locally connected compact metric space is either uncountable or finitely generated. This is related to Shelah's well-known result (1988) which shows that the fundamental group of such a space satisfies a similar condition. We give an example of such a space whose fundamental group is uncountable but whose first homology is trivial, showing that our result does not follow from Shelah's. We clarify a claim made by Pawlikowski (1998) and offer a proof of the...
On the Homology Structure of Submersions.
On the Hurewicz theorem for wedge sum of spheres.
On universality of countable and weak products of sigma hereditarily disconnected spaces
Suppose a metrizable separable space Y is sigma hereditarily disconnected, i.e., it is a countable union of hereditarily disconnected subspaces. We prove that the countable power of any subspace X ⊂ Y is not universal for the class ₂ of absolute -sets; moreover, if Y is an absolute -set, then contains no closed topological copy of the Nagata space = W(I,ℙ); if Y is an absolute -set, then contains no closed copy of the Smirnov space σ = W(I,0). On the other hand, the countable power of...
Oriented singular homology.
Parity complexes
Parity complexes : corrigenda
Periodic maps on Poincaré duality spaces.
Poincaré duality and integral cycles