Abstract
We show that if for any two elementary equivalent structures M,N of size at most continuum in a countable language, Mω/U ≃ Nω/U for some ultrafilter U on ω, then CH holds. We also provide some consistency results related to Keisler and Shelah isomorphism theorems in the absence of CH.
Original language | English |
---|---|
Pages (from-to) | 59-66 |
Number of pages | 8 |
Journal | Fundamenta Mathematicae |
Volume | 260 |
DOIs | |
State | Published - 2023 |
Bibliographical note
Publisher Copyright:© Instytut Matematyczny PAN, 2023.
Keywords
- Keisler–Shelah isomorphism theorem
- forcing
- the continuum hypothesis
- ultrapowers