How special is your Aronszajn tree?
Abstract
The following is consistent: There is a stationary set S such that every Aronszajn tree is S-*-special and there is an Aronszajn tree T such that for every unbounded E we have T is not E-special. This answers a question of Shelah (Proper and Improper Forcing, IX.4.9(5).
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