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Jun 15, 2020 at 7:27 history edited CommunityBot
Commonmark migration
S Feb 19, 2015 at 14:23 history suggested Hanul Jeon CC BY-SA 3.0
I think the inclusion is contextually correct.
Feb 19, 2015 at 14:06 review Suggested edits
S Feb 19, 2015 at 14:23
Apr 16, 2014 at 15:05 comment added Thomas Benjamin @Prof. Hamkins: Can V as characterized in your theorem contain sets nonconstructible relative to L? Do AC and GCH hold in V as characterized by your theorem? In your conception of the set-theoretic multiverse, is there a forcing extension M[G] of this V?
Feb 7, 2014 at 18:53 comment added user46667 Great! Chang's paper is a very nice reference that exactly matches my questions. Thank you very much. I don't know if Chang (or others) investigated around possible relations between these generalized constructible universes and Kunen inconsistency and HOD problem or not.
Feb 7, 2014 at 18:50 vote accept CommunityBot
Feb 7, 2014 at 18:32 history edited Joel David Hamkins CC BY-SA 3.0
Myhill Scott reference
Feb 7, 2014 at 18:22 history edited Joel David Hamkins CC BY-SA 3.0
Chang model
Feb 7, 2014 at 18:21 comment added user46667 In order to give a proof for Kunen's inconsistency theorem using non-first order logics, maybe using the power of logics $\mathcal{L}_{\infty,\infty}$ and $SO$ one can express some expressions which produce a contradiction when we assume there exists a non-trivial elementary embedding from $V$ to itself (and similarly from $HOD$ to itself).
Feb 7, 2014 at 18:00 comment added Noah Schweber Oh, right. That makes more sense.
Feb 7, 2014 at 17:53 comment added Joel David Hamkins @NoahS, since $V_\kappa$ could be much larger than $\kappa$ in size, I think $L([\kappa]^{<\kappa})$ is closer to being right. I'd have to think more about it.
Feb 7, 2014 at 17:46 comment added Noah Schweber Joel, it seems your argument also shows that $L_\kappa$ (in Gina's sense) is $L(V_\kappa)$; is this correct?
Feb 7, 2014 at 17:26 comment added user46667 Is it possible to find a proof of Kunen's inconsistency theorem in terms of infinitary logic by analyzing the structure of $L_{\infty}$ ($=V$)? If yes, is it possible to reformulate this proof for similar result about $L_{SO}$ ($=HOD$)? Maybe there is no non-trivial self-elementary embedding for $V$ because $V$ is $L$ of a too powerful logic like $\mathcal{L}_{\infty,\infty}$ as well as $HOD$ which is $L$ of another too powerful logic like $SO$.
Feb 7, 2014 at 17:15 comment added user46667 It is a really interesting observation that in this dual approach for building Godel's costructible universe by strengthening the expression power of our logic using longer formulas we will reach $V$ and if we increase the expression power of the logic by assuming wider range for quantifiers we will reach $HOD$. It seems $HOD$ and $V$ are some kind of limit $L$ in limit logics (The first one in $\mathcal{L}_{\infty,\infty}$ and the next one in $SO$). Maybe this means one can prove a dual form of Kunen's inconsistency theorem for $HOD$ too.
Feb 7, 2014 at 14:04 history edited Joel David Hamkins CC BY-SA 3.0
added 861 characters in body
Feb 7, 2014 at 13:48 history answered Joel David Hamkins CC BY-SA 3.0