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Length of Boolean algebras and ultraproducts

Menachem Magidor·Saharon Shelah
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Abstract

We prove the consistency with ZFC of ``the length of an ultraproduct of Boolean algebras is smaller than the ultraproduct of the lengths''. Similarly for some other cardinal invariants of Boolean algebras.

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Menachem Magidor, Saharon Shelah. 1998-05-15. Length of Boolean algebras and ultraproducts. https://arxiv.org/abs/math/9805145

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