Nonnormality points of βX∖X

• Autorzy: William Fleissner , Lynne Yengulalp
• Języki publikacji: EN

Abstrakty

EN

Let X be a crowded metric space of weight κ that is either $κ^{ω}$-like or locally compact. Let y ∈ βX∖X and assume GCH. Then a space of nonuniform ultrafilters embeds as a closed subspace of (βX∖X)∖{y} with y as the unique limit point. If, in addition, y is a regular z-ultrafilter, then the space of nonuniform ultrafilters is not normal, and hence (βX∖X)∖{y} is not normal.

Kategorie tematyczne

• 03E45: Inner models, including constructibility, ordinal definability, and core models
• 54D80: Special constructions of spaces (spaces of ultrafilters, etc.)

• Wydawca: Institute of Mathematics Polish Academy of Sciences
• Czasopismo: Fundamenta Mathematicae
• Rocznik: 2011
• Tom: 214
• Numer: 3
• Strony: 269-283

Daty

wydano

2011

Twórcy

autor

William Fleissner

• Department of Mathematics, University of Kansas, Lawrence, KS 66045, U.S.A.

autor

Lynne Yengulalp

• Department of Mathematics, University of Dayton, Dayton, OH 45469, U.S.A.

Identyfikatory

DOI

10.4064/fm214-3-4