ArticleOriginal scientific text
Title
Forcing tightness in products of fans
Authors 1, 2, 3, 4
Affiliations
- Department of Mathematics, University of Tübingen, Tübingen, Germany
- Department of Mathematics, Dartmouth College, Hanover, New Hampshire 03755, U.S.A.
- Department of Mathematics, Union College, Schenectady, New York 12308, U.S.A.
- Department of Mathematical Sciences, Northern Illinois University, DeKalb, Illinois 60115, U.S.A.
Abstract
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.
Bibliography
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Additional information
http://matwbn.icm.edu.pl/ksiazki/fm/fm150/fm15032.pdf
Pages:
211-226
Main language of publication
English
Received
1994-06-14
Accepted
1996-02-29
Published
1996
Exact and natural sciences