Friedman-weiermann Style Independence Results beyond Peano Arithmetic
نویسندگان
چکیده
We expose a pattern for establishing Friedman-Weiermann style independence results according to which there are thresholds of provability of some parameterized variants of well-partial-ordering. For this purpose, we investigate an ordinal notation system for θΩω , the small Veblen ordinal, which is the proof-theoretic ordinal of the theory (Π2-BI)0. We also show that it sometimes suffices to prove the independence w.r.t. PA in order to obtain the same kind of independence results w.r.t. a stronger theory such as (Π2-BI)0.
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