Square Compactness and the filter extension property

David Buhagiar; Mirna Džamonja

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arXiv · 1909.05474

Square Compactness and the filter extension property

David Buhagiar·Mirna Džamonja

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Abstract

We show that the consistency strength of $\kappa$ being $2^\kappa$-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 Juh{\' a}sz.

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David Buhagiar, Mirna Džamonja. 2019-09-12. Square Compactness and the filter extension property. https://arxiv.org/abs/1909.05474

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