Selective Ultrafilters on FIN
نویسنده
چکیده
We consider selective ultrafilters on the collection FIN of all finite nonempty subsets of N. If countablesupport side-by-side Sacks forcing is applied, then every selective ultrafilter in the ground model generates a selective ultrafilter in the extension. We also show that selective ultrafilters localizes the Parametrized Milliken Theorem, and that selective ultrafilters are Ramsey.
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