On invariants for 𝜔₁-separable groups

Eklof, Paul C.; Foreman, Matthew; Shelah, Saharon

doi:10.1090/S0002-9947-1995-1316849-X

On invariants for $\omega _ 1$-separable groups
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by Paul C. Eklof, Matthew Foreman and Saharon Shelah

Trans. Amer. Math. Soc. 347 (1995), 4385-4402

DOI: https://doi.org/10.1090/S0002-9947-1995-1316849-X

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Abstract:

We study the classification of ${\omega _1}$-separable groups by using Ehrenfeucht-Fraïssé games and prove a strong classification result assuming PFA, and a strong non-structure theorem assuming $\diamondsuit$.

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