A note on the tightness of Gδ-modifications

Toshimichi Usuba

doi:10.1016/j.topol.2019.106820

A note on the tightness of G_δ-modifications

Toshimichi Usuba

基幹理工学部

研究成果: Article › 査読

4 被引用数 (Scopus)

抄録

We construct a normal countably tight T₁ space X with t(X_δ)>2^ω. This is an answer to the question posed by Dow-Juhász-Soukup-Szentmiklóssy-Weiss [5]. We also show that if the continuum is not so large, then the tightness of G_δ-modifications of countably tight spaces can be arbitrary large up to the least ω₁-strongly compact cardinal.

本文言語	English
論文番号	106820
ジャーナル	Topology and its Applications
巻	265
DOI	https://doi.org/10.1016/j.topol.2019.106820
出版ステータス	Published - 2019 9月 15

ASJC Scopus subject areas

幾何学とトポロジー

文献へのアクセス

10.1016/j.topol.2019.106820

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引用スタイル

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keywords = "Countably tight, G-modification, Saturated filter, ω-strongly compact cardinal",

author = "Toshimichi Usuba",

note = "Funding Information: This research was supported by JSPS KAKENHI Grant Nos. 18K03403 and 18K03404 . Publisher Copyright: {\textcopyright} 2019 Elsevier B.V.",

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