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minor MathJax edit (the question has been bumped by tag-edit anyway)
Martin Sleziak
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PCF conjecture and fixed points of the $\aleph$-function

Recently Moti Gitik refuted Shelah's PCF conjecture, by producing a countable set $a$ of regular cardinals with $|\operatorname{pcf}(a)| \geq \aleph_1.$ See his papers Short extenders forcings I and Short extenders forcings II.

In Gitik's model the cardinal $\kappa=\sup(a)$ is a fixed point of the $\aleph$-function.

Question. Can we improve Gitik's result to get a countable set $a$ of regular cardinals with $|\operatorname{pcf}(a)| \geq \aleph_1$ such that $\kappa=\sup(a)$ is not a fixed point of the $\aleph$-function?

Mohammad Golshani
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