# Tightness and π-character in centered spaces

Colloquium Mathematicae (1999)

- Volume: 80, Issue: 2, page 297-307
- ISSN: 0010-1354

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topBell, Murray. "Tightness and π-character in centered spaces." Colloquium Mathematicae 80.2 (1999): 297-307. <http://eudml.org/doc/210720>.

@article{Bell1999,

abstract = {We continue an investigation into centered spaces, a generalization of dyadic spaces. The presence of large Cantor cubes in centered spaces is deduced from tightness considerations. It follows that for centered spaces X, πχ(X) = t(X), and if X has uncountable tightness, then t(X) = supκ : $2^κ$ ⊂ X. The relationships between 9 popular cardinal functions for the class of centered spaces are justified. An example is constructed which shows, unlike the dyadic and polyadic properties, that the centered property is not preserved by passage to a zeroset.},

author = {Bell, Murray},

journal = {Colloquium Mathematicae},

keywords = {centered; tightness; compact; π-character; adequate compact space; centered family; dyadic space},

language = {eng},

number = {2},

pages = {297-307},

title = {Tightness and π-character in centered spaces},

url = {http://eudml.org/doc/210720},

volume = {80},

year = {1999},

}

TY - JOUR

AU - Bell, Murray

TI - Tightness and π-character in centered spaces

JO - Colloquium Mathematicae

PY - 1999

VL - 80

IS - 2

SP - 297

EP - 307

AB - We continue an investigation into centered spaces, a generalization of dyadic spaces. The presence of large Cantor cubes in centered spaces is deduced from tightness considerations. It follows that for centered spaces X, πχ(X) = t(X), and if X has uncountable tightness, then t(X) = supκ : $2^κ$ ⊂ X. The relationships between 9 popular cardinal functions for the class of centered spaces are justified. An example is constructed which shows, unlike the dyadic and polyadic properties, that the centered property is not preserved by passage to a zeroset.

LA - eng

KW - centered; tightness; compact; π-character; adequate compact space; centered family; dyadic space

UR - http://eudml.org/doc/210720

ER -

## References

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