Timeline for Ordinal-definable witnesses to the perfect set property?
Current License: CC BY-SA 3.0
6 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jul 1, 2016 at 13:44 | comment | added | Noah Schweber | I've asked a new question based on my comments/motivation here: mathoverflow.net/questions/243461/…. | |
| Jun 30, 2016 at 23:25 | comment | added | Joel David Hamkins | I like the answer a lot. Meanwhile, let me point out that Andreas's set has a perfect subset definable from a real, in fact, from any non-OD real $z$. If you fix $z$, consider the set of reals whose even-bits form a copy of $z$. | |
| Jun 30, 2016 at 16:59 | comment | added | Noah Schweber | EDIT: "Possible" should of course be "possible under AD." | |
| Jun 30, 2016 at 16:50 | vote | accept | Noah Schweber | ||
| Jun 30, 2016 at 16:50 | comment | added | Noah Schweber | Very nice! I forgot that "ordinal definable" was ordinal definable :P. Given this, do you know if it's possible for an uncountable OD set $X$ to have $\theta_0(X)<\theta_0$? | |
| Jun 30, 2016 at 16:18 | history | answered | Andreas Blass | CC BY-SA 3.0 |