I[omega_2] can be the nonstationary ideal on Cof(omega_1)

William J. Mitchell

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I[omega_2] can be the nonstationary ideal on Cof(omega_1)

William J. Mitchell

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Abstract

We answer a question of Shelah by showing that it is consistent that every set of ordinals of cofinality omega_1 in I[omega_2] is nonstationary if and only if it is consistent that that there is a kappa^+ Mahlo cardinal kappa.

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BibTeX RIS

William J. Mitchell. 2007-04-30. I[omega_2] can be the nonstationary ideal on Cof(omega_1). https://arxiv.org/abs/math/0407225

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