Slow P -point Ultrafilters
نویسنده
چکیده
We answer a question of Blass, Di Nasso, and Forti [2, 7] by proving, assuming Continuum Hypothesis or Martin’s Axiom, that (1) there exists a P -point which is not interval-to-one and (2) there exists an interval-to-one P -point which is neither quasi-selective nor weakly Ramsey.
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تاریخ انتشار 2017