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OP-8657Status unassessedLogic and foundations

The Tree Property · Question 35

From ℵ2 to infinity · Historical workshop question

MSC 03 · Mathematical logic and foundations

Editorial mapping of AIMPL source category: Logic. http://aimpl.org/alephtwo/ Not an author-supplied MSC code.

Historical list · status unassessedAs of 2026-09-08Source & evidence ↓
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Problem statement

Suppose κ\kappa is singular with cofinality ω1\omega_1. Let λ=κ+\lambda=\kappa^+. Must □ω1∗\square_{\omega_1}^* hold in a forcing extension where λ\lambda is ℵ2\aleph_2?

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  1. [1]From ℵ2 to infinity link

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