All Questions
Tagged with theories-of-arithmetic definability
1 question with no upvoted or accepted answers
9
votes
0
answers
325
views
Is there a definable model of PA whose domain is a proper class and whose complete theory is not definable?
Assume ZFC. Is there a formula of $\mathcal{L}_\in$ (without parameters) defining a model $\mathcal{M}$ of PA whose domain is a proper class but the complete theory of that model is not definable by ...
