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arXiv · 2408.03487

On Namba Forcing and Minimal Collapses

Maxwell Levine
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Abstract

We build on a 1990 paper of Bukovsky and Coplakova-Hartova. First, we remove the hypothesis of $\textsf{CH}$ from one of their minimality results. Then, using a measurable cardinal, we show that there is a $|\aleph_2^V|=\aleph_1$-minimal extension that is not a $|\aleph_3^V|=\aleph_1$-extension, answering the first of their questions.

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Maxwell Levine. 2024-08-07. On Namba Forcing and Minimal Collapses. https://doi.org/10.1017/fms.2025.10106

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