Products of $k$-spaces and spaces of countable tightness
نویسندگان
چکیده
منابع مشابه
Products of ¿-spaces and Spaces of Countable Tightness
In this paper, we obtain results of the following type: if /: X -» Y is a closed map and X is some "nice" space, and Y2 is a &-space or has countable tightness, then the boundary of the inverse image of each point of Y is "small" in some sense, e.g., Lindelöf or «¿¡-compact. We then apply these results to more special cases. Most of these applications combine the "smallness" of the boundaries o...
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 1982
ISSN: 0002-9947
DOI: 10.1090/s0002-9947-1982-0664043-9