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http://dx.doi.org/10.4134/CKMS.2006.21.2.347

MINIMAL BASICALLY DISCONNECTED COVERS OF PRODUCT SPACES  

Kim Chang-Il (Department of Mathematics Education DanKook University)
Publication Information
Communications of the Korean Mathematical Society / v.21, no.2, 2006 , pp. 347-353 More about this Journal
Abstract
In this paper, we show that if the minimal basically disconnected cover ${\wedge}X_\imath\;of\;X_\imath$ is given by the space of fixed a $Z(X)^#$-ultrafilters on $X_\imath\;(\imath=1,2)\;and\;{\wedge}X_1\;{\times}\;{\wedge}X_2$ is a basically disconnected space, then ${\wedge}X_1\;{\times}\;{\wedge}X_2$ is the minimal basically disconnected cover of $X_1\;{\times}\;X_2$. Moreover, observing that the product space of a P-space and a countably locally weakly Lindelof basically disconnected space is basically disconnected, we show that if X is a weakly Lindelof almost P-space and Y is a countably locally weakly Lindelof space, then (${\wedge}X\;{\times}\;{\wedge}Y,\;{\wedge}_X\;{\times}\;{\wedge}_Y$) is the minimal basically disconnected cover of $X\;{\times}\;Y$.
Keywords
basically disconnected space; covering maps; weakly $Lindel\ddot{o}f$ space;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
연도 인용수 순위
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