On the Equivalence of Certain Consequences of the Proper Forcing Axiom
نویسندگان
چکیده
We prove that a number of axioms, each a consequence of PFA (the Proper Forcing Axiom) are equivalent. In particular we show that TOP (the Thinning-out Principle as introduced by Baumgartner in the Handbook of set-theoretic topology), is equivalent to the following statement: If I is an ideal on co, with co, generators, then there exists an uncountable X C co,, such that either [X]w n I = 0 or [X]w C I. ?
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عنوان ژورنال:
- J. Symb. Log.
دوره 60 شماره
صفحات -
تاریخ انتشار 1995