A Screenable, Σ-relatively Discrete Dowker Space
نویسندگان
چکیده
A Dowker space (that is, a normal space that is not countably metacompact) is constructed which is also screenable and the countable union of discrete subspaces. The construction and proofs are easy modifications of the ones for Balogh’s screenable Dowker space [B1]. Balogh’s example is presented alongside the modification in a new exposition with several new results common to the two spaces, including the fact that each has a discrete collection of 20 = c clopen sets. A conjecture of Balogh’s concerning a submetrizable space is discussed.
منابع مشابه
Some Screenable, Σ-relatively Discrete Dowker Spaces
Dowker spaces (that is, normal spaces that are not countably metacompact) are constructed which are also screenable and the countable union of discrete subspaces. The constructions and proofs are easy modifications of the ones for Balogh’s screenable Dowker space [B1]. Balogh’s example is presented alongside the modifications in a new exposition with several new results common to these spaces, ...
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