
We show that each 0 0 -dimensional Hausdorff space which is scattered can be mapped continuously in a one-to-one way onto a scattered 0 0 -dimensional Hausdorff space of the same weight as its cardinality. This gives an easier and a new proof of the fact that a countable regular space admits a coarser compact Hausdorff topology if and only if it is scattered. We also show that a 0 0 -dimensional, Lindelöf, scattered first-countable Hausdorff space admits a scattered compactification. In particular we give a more direct proof than that of Knaster, Urbanik and Belnov of the fact that a countable scattered metric space is a subspace of [ 1 , Ω ) [1,\Omega ) , and deduce a result of W. H. Young as a corollary.
Compactness, Noncompact covering properties (paracompact, Lindelöf, etc.), Metric spaces, metrizability, Topological spaces and generalizations (closure spaces, etc.)
Compactness, Noncompact covering properties (paracompact, Lindelöf, etc.), Metric spaces, metrizability, Topological spaces and generalizations (closure spaces, etc.)
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