Covering compacta by discrete and other separated sets
نویسندگان
چکیده
منابع مشابه
Covering compacta by discrete and other separated sets
Juhasz and van Mill denote by dis(X) the least cardinal of a cover of X by discrete subspaces. They show that dis(X) ≥ c (and hence the answer to Question 1.1 is positive) for any compact crowded hereditarily normal X. In fact, this follows from their stronger result that for such X, rs(X) + ls(X) ≥ c, where rs(X) (resp., ls(X)) is the least cardinal of a cover of X by right(resp., left)-separa...
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ژورنال
عنوان ژورنال: Topology and its Applications
سال: 2009
ISSN: 0166-8641
DOI: 10.1016/j.topol.2008.12.021