Successive failures of approachability

Spencer Unger

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arXiv · 1702.05062

Successive failures of approachability

Spencer Unger

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Abstract

Motivated by showing that in ZFC we cannot construct a special Aronszajn tree on some cardinal greater than $\aleph_1$, we produce a model in which the approachability property fails (hence there are no special Aronszajn trees) at all regular cardinals in the interval $[\aleph_2, \aleph_{\omega^2+3}]$ and $\aleph_{\omega^2}$ is strong limit.

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BibTeX RIS

Spencer Unger. 2017-02-16. Successive failures of approachability. https://arxiv.org/abs/1702.05062

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