Square compactness and the filter extension property

David Buhagiar, Mirna Dzamonja

Research output: Contribution to journalArticlepeer-review

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We show that the consistency strength of κ being 2κ-square compact is at least weak compact and strictly less than indescribable. This is the first known improvement to the upper bound of strong compactness obtained in 1973 by Hajnal and Juhasz.
Original languageEnglish
Pages (from-to)325-342
Number of pages18
JournalFundamenta Mathematicae
Issue number3
Early online date31 Aug 2020
Publication statusPublished - 2021


  • Box topology
  • Filter extension property
  • Square compact cardinal

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