Timeline for Consistency of Analysis (second order arithmetic)
Current License: CC BY-SA 3.0
7 events
| when toggle format | what | by | license | comment | |
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| Mar 21 at 19:02 | comment | added | Noah Schweber | @C7X To be honest, as a rank outsider I'm rather skeptical of Arai's claim. Certainly he's one of the best proof theorists in the world, but this is a really strong result. I don't know how confident the community is that it's correct yet. | |
| Mar 21 at 4:01 | comment | added | C7X | Does Arai's new preprint (arXiv 2311.12459) claiming an ordinal analysis of second-order arithmetic affect this answer? The supremum of order types of computable well-orders provably well-founded in second-order arithmetic is determined, and in section 8 there are results on its 1-consistency and 2-consistency. | |
| Apr 13, 2017 at 12:58 | history | edited | CommunityBot |
replaced http://mathoverflow.net/ with https://mathoverflow.net/
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| Apr 1, 2014 at 5:56 | vote | accept | Mohammad Golshani | ||
| Mar 8, 2014 at 16:52 | comment | added | François G. Dorais | @MattF. Proof theoretic ordinals are computable ordinals defined using a system of ordinal notations - en.wikipedia.org/wiki/Ordinal_notation | |
| Mar 8, 2014 at 14:59 | comment | added | user44143 | I like the answer; it makes me wonder: What does it mean to have the ordinal "in hand"? Presumably you mean something more that a formula uniquely defining it, perhaps a formula of a certain form. But what form? | |
| Mar 8, 2014 at 8:06 | history | answered | Noah Schweber | CC BY-SA 3.0 |