The distributivity numbers of of P(ω)/fin and its square
نویسندگان
چکیده
We show that in a model obtained by forcing with a countable support iteration of Mathias forcing of length ω2, the distributivity number of P(ω)/fin is ω2, whereas the distributivity number of r.o.(P(ω)/fin) 2 is ω1. This answers an old problem of Balcar, Pelant and Simon, and others.
منابع مشابه
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تاریخ انتشار 1996