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arXiv · 2412.09683

Applications of the Magidor Iteration to Ultrafilter Theory

Tom Benhamou·Gabriel Goldberg
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Abstract

We characterize sums of normal ultrafilters after the Magidor iteration (product) of Prikry forcings over a discrete set of measurable cardinals. We apply this to show that the weak Ultrapower Axiom is not equivalent to the Ultrapower Axiom. We also construct a non-rigid ultrapower and two uniform ultrafilters on different cardinals that have the same ultrapower.

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Tom Benhamou, Gabriel Goldberg. 2024-12-12. Applications of the Magidor Iteration to Ultrafilter Theory. https://doi.org/10.1017/fms.2026.10211

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