Abstract
We prove a preservation theorem for limit steps of countable support iterations of proper forcing notions whose particular cases are preservations of the following properties on limit steps: “no random reals are added”, “μ(Random(V))≠1”, “no dominating reals are added”, “Cohen(V) is not comeager”. Consequently, countable support iterations of σ-centered forcing notions do not add random reals.
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The work was supported by BRF of Israel Academy of Sciences and by grant GA SAV 365 of Slovak Academy of Sciences.
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Judah, H., Repický, M. No random reals in countable support iterations. Israel J. Math. 92, 349–359 (1995). https://doi.org/10.1007/BF02762088
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DOI: https://doi.org/10.1007/BF02762088