Two More Perfectly Normal Non-metrizable Manifolds
نویسندگان
چکیده
We show that there is a perfectly normal non-metrizable manifold if there is a Luzin subset of the real line, and that there is a countably compact perfectly normal non-metrizable manifold in any model of set-theory obtained by adding Cohen reals to a model of ZFC +♦.
منابع مشابه
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An interesting example of a compact Hausdorff space that is often presented in beginning courses in topology is the unit square [0, 1]× [0, 1] with the lexicographic order topology. The closed subspace consisting of the top and bottom edges is perfectly normal. This subspace is often called the Alexandroff double arrow space. It is also sometimes called the “split interval”, since it can be obt...
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