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arXiv · 2002.03573

Double weakness

Shimon Garti·Saharon Shelah
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Abstract

We prove that, consistently, there exists a weakly but not strongly inaccessible cardinal $λ$ for which the sequence $\langle 2^θ:θ<λ\rangle$ is not eventually constant and the weak diamond fails at $λ$. We also prove that consistently diamond fails but a parametrized version of weak diamond holds at some strongly inaccessible $λ$.

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Shimon Garti, Saharon Shelah. 2020-02-10. Double weakness. https://doi.org/10.1007/s10474-021-01132-y

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