A model with a precipitous ideal , but no normal precipitous ideal
نویسنده
چکیده
Starting with a measurable cardinal κ of the Mitchell order κ++ we construct a model with a precipitous ideal on א1 but without normal precipitous ideals. This answers a question by T. Jech and K. Prikry. In the constructed model there are no Q–point precipitous filters on א1, i.e. those isomorphic to extensions of Cubא1 .
منابع مشابه
Some pathological examples of precipitous ideals
We construct a model with an indecisive precipitous ideal and a model with a precipitous ideal with a non precipitous normal ideal below it. Such kind of examples were previously given by M. Foreman [1] and R. Laver [4] respectively. The present examples differ in two ways: firstthey use only a measurable cardinal and secondthe ideals are over a cardinal. Also a precipitous ideal without a norm...
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