Sacks forcing, Laver forcing, and Martin's axiom
نویسندگان
چکیده
منابع مشابه
Sacks forcing, Laver forcing, and Martin's axiom
In this paper we study the question assuming MA+¬CH does Sacks forcing or Laver forcing collapse cardinals? We show that this question is equivalant to question of what is the additivity of Marczewski’s ideal s. We give a proof that it is consistent that Sacks forcing collapses cardinals. On the other hand we show that Laver forcing does not collapse cardinals. Introduction Let S be Sacks perfe...
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ژورنال
عنوان ژورنال: Archive for Mathematical Logic
سال: 1992
ISSN: 0933-5846,1432-0665
DOI: 10.1007/bf01269943