A dichotomy concerning ideals of countable subsets of some set is introduced and proved compatible with the Continuum Hypothesis. The dichotomy has influence not only on the Suslin Hypothesis or the structure of Hausdorff gaps in the quotient algebra $P(\mathbb{N})$/ but also on some higher order statements like for example the existence of Jensen square sequences.
Université Paris 7, C.N.R.S., UPRESA 7056, 2, Place Jussieu, 72251 Paris Cedex 05, France
Bibliografia
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