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arXiv · 2605.14390

Model-theoretic Tameness in finite extensions of groups

Yatir Halevi·Saharon Shelah
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Abstract

It is shown that finite-index extensions and finite-index subgroups of $\omega$-stable groups can be model-theoretically wild. More precisely, there exists an $\omega$-stable group $G$ such that any given countable first-order structure in a finite language is interpretable both in some finite-index extension of $G$ and in some finite-index subgroup of $G$.

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BibTeXRIS

Yatir Halevi, Saharon Shelah. 2026-05-14. Model-theoretic Tameness in finite extensions of groups. https://arxiv.org/abs/2605.14390

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