Abstract
We show that many singular cardinals ë above a strongly compact cardinal have regular ultrafilters D that violate the finite square principle □ λ,Dfin introduced in [3]. For such ultrafilters D and cardinals λ there are models of size λ for which Mλ/D is not λ++ -universal and elementarily equivalent models M and N of size λ for which M λ/D and Nλ/D are non-isomorphic. The question of the existence of such ultrafilters and models was raised in [I].
Original language | English |
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Pages (from-to) | 817-823 |
Number of pages | 7 |
Journal | Journal of Symbolic Logic |
Volume | 73 |
Issue number | 3 |
DOIs | |
State | Published - Sep 2008 |