Tightness and π-character in centered spaces

• Autorzy: Murray Bell
• Języki publikacji: EN

Abstrakty

EN

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) = sup{κ : $2^κ$ ⊂ 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.

Słowa kluczowe

EN

centered; tightness; compact; π-character

• Wydawca: Institute of Mathematics Polish Academy of Sciences
• Czasopismo: Colloquium Mathematicum
• Rocznik: 1999
• Tom: 80
• Numer: 2
• Strony: 297-307

Daty

wydano

1999

otrzymano

1998-09-28

poprawiono

1999-03-01

Twórcy

autor

Murray Bell

• Department of Mathematics University of Manitoba Winnipeg, Manitoba Canada R3T 2N2

Bibliografia

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