Answer by Andrés E. Caicedo for Consistency of...
The person you want to ask about consistency strength is Ralf Schindler. Years ago ("Successive weakly compact or singular cardinals", Symbolic Logic 64 (1999), no. 1, 139–146) Ralf showed that the...
View ArticleConsistency of $\operatorname{cf}(\omega_1)=\operatorname{cf}(\omega_2)=\omega$
It is known that if $\operatorname{cf}(\omega_1)=\operatorname{cf}(\omega_2)=\omega$ then $0^\#$ exists.I am familiar with the Feferman-Levy model in which $\omega_1$ is singular, which has the same...
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