| Full text | |
| Author(s): |
Total Authors: 2
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| Affiliation: | [1] Univ Brasilia, Philosophy Dept, Brasilia, DF - Brazil
[2] Univ Coll, Philosophy, Oxford - England
[3] Univ Oxford, Log, Fac Philosophy, Dept Math, Oxford - England
Total Affiliations: 3
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| Document type: | Journal article |
| Source: | JOURNAL OF SYMBOLIC LOGIC; v. 86, n. 2, p. 609-634, JUN 2021. |
| Web of Science Citations: | 0 |
| Abstract | |
In contrast to the robust mutual interpretability phenomenon in set theory, Ali Enayat proved that bi-interpretation is absent: distinct theories extending ZF are never bi-interpretable and models of ZF are bi-interpretable only when they are isomorphic. Nevertheless, for natural weaker set theories, we prove, including Zermelo-Fraenkel set theory ZFC(-) without power set and Zermelo set theory Z, there are nontrivial instances of bi-interpretation. Specifically, there are well-founded models of ZFC- that are bi-interpretable, but not isomorphic-even < H-omega 1, is an element of > and < H-omega 2, is an element of > can be bi-interpretable-and there are distinct bi-interpretable theories extending ZFC-. Similarly, using a construction of Mathias, we prove that every model of ZF is bi-interpretable with a model of Zermelo set theory in which the replacement axiom fails. (AU) | |
| FAPESP's process: | 17/21020-0 - On the conditions for a comparison of ontological commitment between theories |
| Grantee: | Alfredo Roque de Oliveira Freire Filho |
| Support type: | Scholarships abroad - Research Internship - Doctorate (Direct) |