An Inconsistent Forcing Axiom at ω₂

2020/08/03 by Todorčević, Stevo, Xiong, Shihao
#03E05 #03E35 #03E57(Primary) #FOS: Mathematics #Logic (math.LO)

paper · doi:10.48550/arxiv.2008.01225

Abstract

We show that the forcing axiom for countably compact, ω₂-Knaster, well-met posets is inconsistent. This is supplemental to an inconsistency result of Shelah and sets a new limit to the generalization of Martin's Axiom to the stage of ω₂.

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