On mappings of compact spaces into Cartesian spaces
β Scribed by Semeon A. Bogatyi; Vitaly V. Fedorchuk; Jan van Mill
- Publisher
- Elsevier Science
- Year
- 2000
- Tongue
- English
- Weight
- 114 KB
- Volume
- 107
- Category
- Article
- ISSN
- 0166-8641
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β¦ Synopsis
Eilenberg proved that if a compact space X admits a zero-dimensional map f :X β Y , where Y is m-dimensional, then there exists a map h :X β I m+1 such that f Γ h :X β Y Γ I m+1 is an embedding. In this paper we prove generalizations of this result for Ο -compact subsets of arbitrary spaces. An example of a compact space X and of a zero-dimensional Ο -compact subset A β X is given such that for any continuous function f :X β R which is one-to-one on the set A and any G Ξ΄ -subset B of X with B β A the restriction f |B :B β R has infinite fibers. This example is used to demonstrate that our results are sharp.
π SIMILAR VOLUMES
It is shown that every compact space X can be embedded as a retract of a compact space Y so that every regular open Baire subset of Y is clopen. Furthermore, if X is a continuum, Y is a continuum as well and Y has only two regular open Baire subsets. This extends a result of V.V. FedorZuk.
An atom is a hereditarily indecomposable continuum. A Bing space is a compacturn in which every subcontinuum is an atom. It is proved that if K is a closed subset of a Bing space X then (i) if a(K) = 0 then every map of K in a connected ANR extends upon X; (ii) if g(K) < n then every map of K in &+