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It is well-known that the following reflection principle is consistent relative to a supercompact:

For all $\kappa \geq \omega_2$ and all stationary $S \subseteq [\kappa]^\omega$, there is $X \subseteq \kappa$ such that $\omega_1 \subseteq X$, $|X| = \omega_1$, and $S \cap [X]^\omega$ is stationary.

Let us say $Refl(\kappa,\mu)$ holds when:

For all stationary $S \subseteq [\kappa]^\omega$, there is $X \subseteq \kappa$ such that $\mu \subseteq X$, $|X| = \mu$, and $S \cap [X]^\omega$ is stationary.

If $\mu$ is regular and there is a supercompact above $\mu$, then by Levy-collapsing that supercompact to be $\mu^+$, we get a model of $(\forall \kappa \geq \mu^+)Refl(\kappa,\mu)$.

Question: Is $Refl(\aleph_{\omega+1},\aleph_\omega)$ consistent?

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    $\begingroup$ That reflection principle implies the version of Strong Chang's Conjecture you asked me about. Though I guess you probably already know that, and maybe that's why you asked the question... $\endgroup$
    – Sean Cox
    Commented Nov 13, 2018 at 14:26
  • $\begingroup$ @SeanCox: We might need to go to $Refl(|H_{\aleph_{\omega+2}}|,\aleph_\omega)$ to deduce the version of SCC. $\endgroup$ Commented Nov 14, 2018 at 11:59
  • $\begingroup$ Yes, you're right. $\endgroup$
    – Sean Cox
    Commented Nov 14, 2018 at 14:03

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