Cell-like decompositions arising from mismatched sewings: applications to 4-manifolds
Knot complements in the n-sphere are characterized. A connected open subset W of is homeomorphic with the complement of a locally flat (n-2)-sphere in , n ≥ 4, if and only if the first homology group of W is infinite cyclic, W has one end, and the homotopy groups of the end of W are isomorphic to those of in dimensions less than n/2. This result generalizes earlier theorems of Daverman, Liem, and Liem and Venema.
We prove a structure theorem for closed, orientable 5-manifolds with fundamental group and second Stiefel-Whitney class equal to zero on . This structure theorem is then used to construct contact structures on such manifolds by applying contact surgery to fake projective spaces and certain -quotients of .
In this paper we present selected properties of barycentric coordinates in the Euclidean topological space. We prove the topological correspondence between a subset of an affine closed space of εn and the set of vectors created from barycentric coordinates of points of this subset.