2023/02/10 by Dilip Raghavan, Juris Steprāns, Raghavan, Dilip +1
Engineering · #Smart Parking Systems Research
paper · pdf · doi:10.48550/arxiv.2302.05539
It will be shown to be consistent that there are at least two non-isomorphic selective ultrafilters, but no stable ordered-union ultrafilters. This answers a question of Blass from his 1987 paper which introduced the concept of a stable ordered-union ultrafilter.