Embedding S(X) into S(Y) when Y is compact and S is not.
Ends and quasicomponents
Let X be a connected locally compact metric space. It is known that if X is locally connected, then the space of ends (Freudenthal ends), EX, can be represented as the inverse limit of the set (space) S(X C) of components of X C, i.e., as the inverse limit of the inverse system . In this paper, the above result is significantly improved. It is shown that for a space which is not locally connected, we can replace the space of components by the space of quasicomponents Q(X C) of X C. The following...
Equivariant embeddings and compactifications of free -spaces.
Erratum : Compactifications de Bohr d'anneaux et de modules
Erweiterungen topologischer Räume.
Euclidean Convexity Cannot be Compactified.
Extending continuous functions on X x Y to subsets of βX x βY
Extending Linear Space-Valued Functions.
Extending maps from dense subspaces .
Extending monotone mappings
Extending the ideal of nowhere dense subsets of rationals to a P-ideal
We show that the ideal of nowhere dense subsets of rationals cannot be extended to an analytic P-ideal, ideal nor maximal P-ideal. We also consider a problem of extendability to a non-meager P-ideals (in particular, to maximal P-ideals).
Extension properties of Stone-Čech coronas and proper absolute extensors
We characterize, in terms of X, the extensional dimension of the Stone-Čech corona βX∖X of a locally compact and Lindelöf space X. The non-Lindelöf case is also settled in terms of extending proper maps with values in , where L is a finite complex. Further, for a finite complex L, an uncountable cardinal τ and a -set X in the Tikhonov cube we find a necessary and sufficient condition, in terms of , for X to be in the class AE([L]). We also introduce a concept of a proper absolute extensor and...
Extensions of topological and semitopological groups and the product operation
The main results concern commutativity of Hewitt-Nachbin realcompactification or Dieudonné completion with products of topological groups. It is shown that for every topological group that is not Dieudonné complete one can find a Dieudonné complete group such that the Dieudonné completion of is not a topological group containing as a subgroup. Using Korovin’s construction of -dense orbits, we present some examples showing that some results on topological groups are not valid for semitopological...
Extensions of unbounded topological spaces