We prove two theorems that characterize tightness in certain products of fans in terms of families of integer-valued functions. We also define several notions of forcing that allow us to manipulate the structure of the set of functions from some cardinal θ to ω, and hence, the tightness of these products. These results give new constructions of first countable <θ-cwH spaces that are not ≤θ-cwH.
@article{bwmeta1.element.bwnjournal-article-fmv150i3p211bwm,
author = {J\"org Brendle and Tim La Berge},
title = {Forcing tightness in products of fans},
journal = {Fundamenta Mathematicae},
volume = {149},
year = {1996},
pages = {211-226},
zbl = {0867.54002},
language = {en},
url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-fmv150i3p211bwm}
}
Brendle, Jörg; La Berge, Tim. Forcing tightness in products of fans. Fundamenta Mathematicae, Tome 149 (1996) pp. 211-226. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-fmv150i3p211bwm/
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