Ultrafilters on Ω—their Ideals and Their Cardinal Characteristics
نویسنده
چکیده
For a free ultrafilter U on ω we study several cardinal characteristics which describe part of the combinatorial structure of U . We provide various consistency results; e.g. we show how to force simultaneously many characters and many π–characters. We also investigate two ideals on the Baire space ωω naturally related to U and calculate cardinal coefficients of these ideals in terms of cardinal characteristics of the underlying ultrafilter.
منابع مشابه
ar X iv : m at h / 97 10 21 7 v 1 [ m at h . L O ] 1 5 O ct 1 99 7 Ultrafilters on ω — — their ideals and their cardinal characteristics
For a free ultrafilter U on ω we study several cardinal characteristics which describe part of the combinatorial structure of U . We provide various consistency results; e.g. we show how to force simultaneously many characters and many π–characters. We also investigate two ideals on the Baire space ω naturally related to U and calculate cardinal coefficients of these ideals in terms of cardinal...
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تاریخ انتشار 1999