Abstract
We study some limitations and possible occurrences of uniform ultra- filters on ordinals without the axiom of choice. We prove an Easton-like theorem about the possible spectrum of successors of regular cardinals which carry uniform ultrafilters; we also show that this spectrum is not necessarily closed.
| Original language | English |
|---|---|
| Pages (from-to) | 285-298 |
| Number of pages | 14 |
| Journal | Commentationes Mathematicae Universitatis Carolinae |
| Volume | 60 |
| Issue number | 2 |
| DOIs | |
| State | Published - 2019 |
| Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2019 Charles University, Faculty of Mathematics and Physics.
Keywords
- Axiom of choice
- Measurable cardinal
- Strongly compact cardinal
- Uniform ultrafilter