Journal of the Mathematical Society of Japan

Reflection principles for $\omega_2$ and the semi-stationary reflection principle

Toshimichi USUBA

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Starting from a model with a weakly compact cardinal, we construct a model in which the weak stationary reflection principle for $\omega_2$ holds but the Fodor-type reflection principle for $\omega_2$ fails. So the stationary reflection principle for $\omega_2$ fails in this model. We also construct a model in which the semi-stationary reflection principle holds but the Fodor-type reflection principle for $\omega_2$ fails.

Article information

J. Math. Soc. Japan, Volume 68, Number 3 (2016), 1081-1098.

First available in Project Euclid: 19 July 2016

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Primary: 03E35: Consistency and independence results
Secondary: 03E05: Other combinatorial set theory

stationary reflection principle semi-stationary reflection principle Fodor-type reflection principle


USUBA, Toshimichi. Reflection principles for $\omega_2$ and the semi-stationary reflection principle. J. Math. Soc. Japan 68 (2016), no. 3, 1081--1098. doi:10.2969/jmsj/06831081.

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