Limits in the uniform ultrafilters

Baker, Joni; Kunen, Kenneth

doi:10.1090/S0002-9947-01-02843-4

Limits in the uniform ultrafilters
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by Joni Baker and Kenneth Kunen PDF

Trans. Amer. Math. Soc. 353 (2001), 4083-4093 Request permission

Abstract:

Let $u(\kappa )$ be the space of uniform ultrafilters on $\kappa$. If $\kappa$ is regular, then there is an $\mathbf x \in u(\kappa )$ which is not an accumulation point of any subset of $u(\kappa )$ of size $\kappa$ or less. $\mathbf x$ is also good, in the sense of Keisler.

References

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