Spaces with countable $sn$-networks
Commentationes Mathematicae Universitatis Carolinae, Tome 45 (2004) no. 1, pp. 169-176
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In this paper, we prove that a space $X$ is a sequentially-quotient $\pi$-image of a metric space if and only if $X$ has a point-star $sn$-network consisting of $cs^*$-covers. By this result, we prove that a space $X$ is a sequentially-quotient $\pi$-image of a separable metric space if and only if $X$ has a countable $sn$-network, if and only if $X$ is a sequentially-quotient compact image of a separable metric space; this answers a question raised by Shou Lin affirmatively. We also obtain some results on spaces with countable $sn$-networks.
Classification :
54C05, 54C10, 54D65, 54E40
Keywords: separable metric space; sequentially-quotient ($\pi$; compact) mapping; point-star $sn$-network; $cs*$-cover
Keywords: separable metric space; sequentially-quotient ($\pi$; compact) mapping; point-star $sn$-network; $cs*$-cover
@article{CMUC_2004__45_1_a12,
author = {Ying, Ge},
title = {Spaces with countable $sn$-networks},
journal = {Commentationes Mathematicae Universitatis Carolinae},
pages = {169--176},
publisher = {mathdoc},
volume = {45},
number = {1},
year = {2004},
mrnumber = {2076868},
zbl = {1098.54025},
language = {en},
url = {http://geodesic.mathdoc.fr/item/CMUC_2004__45_1_a12/}
}
Ying, Ge. Spaces with countable $sn$-networks. Commentationes Mathematicae Universitatis Carolinae, Tome 45 (2004) no. 1, pp. 169-176. http://geodesic.mathdoc.fr/item/CMUC_2004__45_1_a12/