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Semiproper forcing axiom implies Martin maximum but not PFA+
Published online by Cambridge University Press: 12 March 2014
Abstract
We prove that MM (Martin maximum) is equivalent (in ZFC) to the older axiom SPFA (semiproper forcing axiom). We also prove that SPFA does not imply SPFA+ or even PFA+ (using the consistency of a large cardinal).
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- Copyright © Association for Symbolic Logic 1987
References
REFERENCES
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