Čech-completeness and ultracompleteness in “nice spaces”
de Luna, Miguel López ; Tkachuk, Vladimir Vladimirovich
Commentationes Mathematicae Universitatis Carolinae, Tome 43 (2002), p. 515-524 / Harvested from Czech Digital Mathematics Library
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We prove that if $X^n$ is a union of $n$ subspaces of pointwise countable type then the space $X$ is of pointwise countable type. If $X^\omega $ is a countable union of ultracomplete spaces, the space $X^\omega $ is ultracomplete. We give, under CH, an example of a Čech-complete, countably compact and non-ultracomplete space, giving thus a partial answer to a question asked in [BY2].

Publié le : 2002-01-01
Classification:  54C10,  54C25,  54D06,  54D25,  54D35,  54D70,  54E50,  54F65,  54H11 
@article{119341,
     author = {Miguel L\'opez de Luna and Vladimir Vladimirovich Tkachuk},
     title = {\v Cech-completeness and ultracompleteness in ``nice spaces''},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     volume = {43},
     year = {2002},
     pages = {515-524},
     zbl = {1090.54023},
     mrnumber = {1920527},
     language = {en},
     url = {http://dml.mathdoc.fr/item/119341}
}

de Luna, Miguel López; Tkachuk, Vladimir Vladimirovich. Čech-completeness and ultracompleteness in “nice spaces”. Commentationes Mathematicae Universitatis Carolinae, Tome 43 (2002) pp. 515-524. http://gdmltest.u-ga.fr/item/119341/

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