arXiv · 1809.04670
It is shown that the compositum $ \mathbb Q^{(2)}$ of all degree 2 extensions of $\mathbb Q$ has undecidable theory.
Carlos Martinez-Ranero, Javier Utreras, Carlos R. Videla. 2018-09-12. Undecidability of $\mathbb Q^{(2)}$. https://doi.org/10.1090/proc/14849
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