On the cardinality of functionally Hausdorff spaces
Commentationes Mathematicae Universitatis Carolinae (1996)
- Volume: 37, Issue: 4, page 797-801
- ISSN: 0010-2628
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topFedeli, Alessandro. "On the cardinality of functionally Hausdorff spaces." Commentationes Mathematicae Universitatis Carolinae 37.4 (1996): 797-801. <http://eudml.org/doc/247911>.
@article{Fedeli1996,
abstract = {In this paper two new cardinal functions are introduced and investigated. In particular the following two theorems are proved:
(i) If $\,X$ is a functionally Hausdorff space then $|X| \le 2^\{fs(X) \psi _\{\tau \}(X)\}$;
(ii) Let $X$ be a functionally Hausdorff space with $fs(X) \le \kappa $. Then there is a subset $S$ of $X$ such that $|S| \le 2^\{\kappa \}$ and $X = \bigcup \lbrace cl_\{\tau \theta \}(A): A \in [S]^\{\le \kappa \} \rbrace $.},
author = {Fedeli, Alessandro},
journal = {Commentationes Mathematicae Universitatis Carolinae},
keywords = {cardinal functions; $\tau $-pseudocharacter; functional spread; -pseudocharacter; functional spread; cardinal characteristics of a topological space},
language = {eng},
number = {4},
pages = {797-801},
publisher = {Charles University in Prague, Faculty of Mathematics and Physics},
title = {On the cardinality of functionally Hausdorff spaces},
url = {http://eudml.org/doc/247911},
volume = {37},
year = {1996},
}
TY - JOUR
AU - Fedeli, Alessandro
TI - On the cardinality of functionally Hausdorff spaces
JO - Commentationes Mathematicae Universitatis Carolinae
PY - 1996
PB - Charles University in Prague, Faculty of Mathematics and Physics
VL - 37
IS - 4
SP - 797
EP - 801
AB - In this paper two new cardinal functions are introduced and investigated. In particular the following two theorems are proved:
(i) If $\,X$ is a functionally Hausdorff space then $|X| \le 2^{fs(X) \psi _{\tau }(X)}$;
(ii) Let $X$ be a functionally Hausdorff space with $fs(X) \le \kappa $. Then there is a subset $S$ of $X$ such that $|S| \le 2^{\kappa }$ and $X = \bigcup \lbrace cl_{\tau \theta }(A): A \in [S]^{\le \kappa } \rbrace $.
LA - eng
KW - cardinal functions; $\tau $-pseudocharacter; functional spread; -pseudocharacter; functional spread; cardinal characteristics of a topological space
UR - http://eudml.org/doc/247911
ER -
References
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