Timeline for A question on models of set theory and Lebesgue measure
Current License: CC BY-SA 3.0
5 events
| when toggle format | what | by | license | comment | |
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| Dec 17, 2014 at 20:26 | vote | accept | user38200 | ||
| Dec 17, 2014 at 20:13 | comment | added | Joel David Hamkins | I edited to give a little more explanation of the complexity. Basically, it is $\Sigma_2$ because you can verify it in any sufficiently large $V_\theta$, and indeed, you don't have to go very high. Statements that are not $\Sigma_2$ must involve set-theoretic properties that stretch up arbitrarily high in the set-theoretic universe. Lebesgue measurability is not like that, since once you have the reals and all the sets of reals, then all the issues about measurability will be determined. | |
| Dec 17, 2014 at 20:11 | history | edited | Joel David Hamkins | CC BY-SA 3.0 |
added 344 characters in body
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| Dec 17, 2014 at 20:03 | comment | added | user38200 | Thanks, I suspected so but couldn't figure that the complexity of the definition of the set on nonmeasurable sets is $\Sigma_2$. | |
| Dec 17, 2014 at 19:59 | history | answered | Joel David Hamkins | CC BY-SA 3.0 |