Abstract
We investigate the effect of a variant of Matet forcing on ultrafilters in the ground model and give a characterization of those $P$–points that survive such forcing, answering a question left open by Blass. We investigate the question of when this variant of Matet forcing can be used to diagonalize small filters without destroying $P$–points in the ground model. We also deal with the question of generic existence of stable ordered–union ultrafilters.
Citation
Todd Eisworth. "Forcing and stable ordered-union ultrafilters." J. Symbolic Logic 67 (1) 449 - 464, March 2002. https://doi.org/10.2178/jsl/1190150054
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