Many forcing axioms for all regular uncountable cardinals

by Shelah. [Sh:832]

Our original aim was, in Abelian group theory to prove the consistency of: lambda is strong limit singular and for some properties of abelian groups which are relatives of being free, the compactness in singular fails. In fact this should work for R-modules, etc. As in earlier cases part of the work is analyzing how to move between the set theory and the algebra.

Set theoretically we try to force a universe which satisfies G.C.H. and diamond holds for many stationary sets but, for every regular

uncountable lambda, in some sense anything which ``may'' hold for some stationary set, does hold for some stationary set. More specifically we try to get a universe satisfying GCH such that e.g. for regular kappa < lambda there are pairs (S,B),S subseteq S^lambda_kappa stationary, B subseteq

{{H}}(lambda), which satisfies some pregiven forcing axiom related to (S,B), (so (lambda backslash S)-complete, i.e. ``trivial outside S'') underline {but} no more, i.e. slightly

stronger versions fail (for this S). So set theoretically we try to get a universe satisfying G.C.H. but still satisfies ``many'', even for a maximal family in some sense, of forcing axioms of the form ``for some stationary'' while preserving GCH. As completion of the work lag for long, here we deal only with the set theory.


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