Timeline for How "small" can an ordinal be made by forcing?
Current License: CC BY-SA 3.0
3 events
| when toggle format | what | by | license | comment | |
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| Sep 3, 2015 at 6:54 | comment | added | Yair Hayut | You can change the set of ordinals which are countable in HOD by forcing, and this set can be smaller than $\omega_1^V$. | |
| Sep 2, 2015 at 12:18 | comment | added | Miha Habič | You definitely cannot make a nonrecursive ordinal recursive by forcing. Being recursive is witnessed by a Turing machine, i.e. a natural number, and these aren't affected by forcing. | |
| Sep 2, 2015 at 11:28 | history | asked | Simon Henry | CC BY-SA 3.0 |