Timeline for In $L$, does there exist a definable non-principal ultrafilter on $\mathbb{N}$
Current License: CC BY-SA 3.0
4 events
| when toggle format | what | by | license | comment | |
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| Jan 21, 2014 at 19:39 | comment | added | Noah Schweber | Argh, quite right - that's one of those things that sounds totally innocuous to say, but then someone points out that you need to think about it . . . :) Thanks for reminding me (that's one of my favorite results)! | |
| Jan 21, 2014 at 18:44 | vote | accept | Mike Battaglia | ||
| Jan 21, 2014 at 16:01 | comment | added | Asaf Karagila♦ | Countably many definable where, and how? Recall the result about pointwise definable models (Hamkins, Linetsky, Reitz). In these models every element is definable. Including all $2^{2^{\aleph_0}}$ ultrafilters. | |
| Jan 21, 2014 at 7:19 | history | answered | Noah Schweber | CC BY-SA 3.0 |