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arXiv · 1907.11765

Ultrafilters on singular cardinals of uncountable cofinality

James Cummings·Charles Morgan
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Abstract

We prove that consistently there is a singular cardinal $κ$ of uncountable cofinality such that $2^κ$ is weakly inaccessible, and every regular cardinal strictly between $κ$ and $2^κ$ is the character of some uniform ultrafilter on $κ$.

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James Cummings, Charles Morgan. 2019-07-26. Ultrafilters on singular cardinals of uncountable cofinality. https://arxiv.org/abs/1907.11765

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