Abstract
We deal with the problem of preserving various versions of completeness in (<κ)-support iterations of forcing notions, generalizing the case “S-complete proper is preserved by CS iterations for a stationary costationaryS⊆ω 1”. We give applications to Uniformization and the Whitehead problem. In particular, for a strongly inaccessible cardinalκ and a stationary setS⊆κ with fat complement we can have uniformization for every (A δ :δ ∈S′),A δ ⊆δ = supA δ , cf (δ) = otp(A δ ) and a stationary non-reflecting setS′⊆S (see B.8.2).
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M. Dzamonja and S. Shelah.,Saturated filters at successors of singulars, weak reflection and yet another weak club principle, Annals of Pure and Applied Logic79 (1996), 289–316. math.LO/9601219.
P. C. Eklof and A. Mekler,Almost Free Modules: Set Theoretic Methods, Volume 46, Elsevier Science Publishers B.V., Amsterdam, 1990.
R. Göbel and S. Shelah,GCH implies the existence of many rigid almost free abelian groups, inProceedings of the Conference on Abelian Groups in Colorado Springs, 1995, Volume 182 of Lecture Notes in Pure and Applied Mathematics, Marcel Dekker, New York, 1996, pp. 253–271. math.GR/0011185.
J. Gregory,Higher Souslin trees and the generalized continuum hypothesis, Journal of Symbolic Logic41 (1976), 663–671.
T. Jech,Set Theory, Academic Press, New York, 1978.
M. Magidor and S. Shelah,When does almost free imply free? (For groups, transversals etc.), Journal of the American Mathematical Society7 (1994), 769–830.
A. H. Mekler and S. Shelah,Diamond and λ-systems., Fundamenta Mathematicae131 (1988), 45–51.
A. H. Mekler and S. Shelah,Uniformization principles., The Journal of Symbolic Logic54 (1989), 441–459.
S. Shelah,A compactness theorem for singular cardinals, free algebras, Whitehead problem and transversals, Israel Journal of Mathematics21 (1975), 319–349.
S. Shelah,Whitehead groups may be not free, even assuming CH. I, Israel Journal of Mathematics28 (1977), 193–204.
S. Shelah,On successors of singular cardinals., inLogic Colloquium ′78 (Mons, 1978), Volume 97 of Studies in Logic and the Foundations of Mathematics, North-Holland, Amsterdam-New York, 1979, pp. 357–380.
S. Shelah,Diamonds, uniformization, The Journal of Symbolic Logic49 (1984), 1022–1033.
S. Shelah,Cardinal Arithmetic, Volume 29 ofOxford Logic Guides, Oxford University Press, 1994.
S. Shelah,Proper and improper forcing, inPerspectives in Mathematical Logic, Springer, New York, 1998.
S. Shelah,Analytical Guide and Corrections to [16]. math.LO/9906022.
A. Rosłanowski and S. Shelah,Iteration of λ-complete forcing notions not collapsing λ +, International Journal of Mathematics and Mathematical Sciences28 (2001), 63–82. math.LO/9906024..
S. Shelah,Successor of singulars: Combinatorics and not collapsing cardinals ≤ κ in (<κ)-support iterations, Israel Journal of Mathematics134 (2003), 127–155. math.LO/9808140.
C. Steinhorn and J. King,The Uniformization property for ℵ 2, Israel Journal of Mathematics36 (1980), 248–256.
A. Rosłanowski and S. Shelah,Sheva-Sheva-Sheva: Large Creatures, in preparation.
S. Shelah,Middle diamond, Archive for Mathematical Logic, submitted.
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Research supported by The German-Israeli Foundation for Scientific Research & Development Grant No. G-294.081.06/93 and by The National Science Foundation Grant No. 144-EF67. Publication No. 587.
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Shelah, S. Not collapsing cardinals ≤κ in (<κ)-support iterations. Isr. J. Math. 136, 29–115 (2003). https://doi.org/10.1007/BF02807192
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DOI: https://doi.org/10.1007/BF02807192