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Full reflection of stationary sets below aleph_omega

Thomas Jech·Saharon Shelah
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Abstract

It is consistent that for every n >= 2, every stationary subset of omega_n consisting of ordinals of cofinality omega_k where k = 0 or k <= n-3 reflects fully in the set of ordinals of cofinality omega_{n-1}. We also show that this result is best possible.

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Thomas Jech, Saharon Shelah. 1990-01-15. Full reflection of stationary sets below aleph_omega. https://arxiv.org/abs/math/9201242

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