The Category Dichotomy for Ideals

Abstract

We provide a counterexample to the Category Dichotomy in the framework of ZFC. That is, we prove the existence of an ideal on ω that is not Katetov below nwd and does not have restrictions above ED. We also prove that in the Laver model every tall P-ideal is Katetov-Blass above EDfin and that it is consistent that every Q+ ideal is meager.

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