Compactness and Incompactness Phenomena in Set Theory
نویسنده
چکیده
We prove two results with a common theme: the tension between compactness and incompactness phenomena in combinatorial set theory. Theorem 1 uses PCF theory to prove a sort of “compactness” for a version of Dzamonja and Shelah’s strong non-reflection principle. Theorem 2 investigates Jensen’s subcompact cardinals and their relationship with stationary set reflection and the failure of the square principle.
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