Semi-proper forcing, remarkable cardinals, and Bounded Martin's Maximum

نویسنده

  • Ralf Schindler
چکیده

We show that L(R) absoluteness for semi-proper forcings is equiconsistent with the existence of a remarkable cardinal, and hence by [6] with L(R) absoluteness for proper forcings. By [7], L(R) absoluteness for stationary set preserving forcings gives an inner model with a strong cardinal. By [3], the Bounded Semi-Proper Forcing Axiom (BSPFA) is equiconsistent with the Bounded Proper Forcing Axiom (BPFA), which in turn is equiconsistent with a reflecting cardinal. We show that Bounded Martin’s Maximum (BMM) is much stronger than BSPFA in that if BMM holds, then for every X ∈ V , X exists.

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عنوان ژورنال:
  • Math. Log. Q.

دوره 50  شماره 

صفحات  -

تاریخ انتشار 2004