کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4662382 1633542 2007 30 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Guessing and non-guessing of canonical functions
موضوعات مرتبط
مهندسی و علوم پایه ریاضیات منطق ریاضی
پیش نمایش صفحه اول مقاله
Guessing and non-guessing of canonical functions
چکیده انگلیسی

It is possible to control to a large extent, via semiproper forcing, the parameters (β0,β1) measuring the guessing density of the members of any given antichain of stationary subsets of ω1 (assuming the existence of an inaccessible limit of measurable cardinals). Here, given a pair (β0,β1) of ordinals, we will say that a stationary set S⊆ω1 has guessing density (β0,β1) if β0=γ(S) and , where γ(S∗) is, for every stationary S∗⊆ω1, the infimum of the set of ordinals τ≤ω1+1 for which there is a function F:S∗⟶P(ω1) with ot(F(ν))<τ for all ν∈S∗ and with {ν∈S∗:g(ν)∈F(ν)} stationary for every α<ω2 and every canonical function g for α. This work involves an analysis of iterations of models of set theory relative to sequences of measures on possibly distinct measurable cardinals.As an application of these techniques I show how to force, from the existence of a supercompact cardinal, a model of in which there is a well-order of H(ω2) definable, over 〈H(ω2),∈〉, by a formula without parameters.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Annals of Pure and Applied Logic - Volume 146, Issues 2–3, May 2007, Pages 150-179