Condensations of Cp(X) onto σ-compact spaces

Vladimir V. Tkachuk

Abstract

We show, in particular, that if nw(Nt) ≤  k for any t ϵ  T and C is a dense subspace of the product ǁ{Nt : t 2 T} then, for any continuous (not necessarily surjective) map ϕ : C_K of C into a compact space K with t(K) ≤ k, we have ψ(ϕ (C)) ≤ k. This result has several applications in Cp-theory. We prove, among other things, that if K is a non-metrizable Corson compact space then Cp(K) cannot be condensed onto a σ-compact space. This answers two questions published by Arhangel’skii and Pavlov.


Keywords

Condensation; Continuous image; Lindelöf Σ-space; σ –compact space; Topology of pointwise convergence; Network weight; Tightness; Lindelöf space

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References

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