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arXiv · 1505.02147

Definable choice for a class of weakly o-minimal theories

Michael C. Laskowski·Christopher S. Shaw
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Abstract

Given an o-minimal structure ${\mathcal M}$ with a group operation, we show that for a properly convex subset $U$, the theory of the expanded structure ${\mathcal M}'=({\mathcal M},U)$ has definable Skolem functions precisely when ${\mathcal M}'$ is valuational. As a corollary, we get an elementary proof that the theory of any such ${\mathcal M}'$ does not satisfy definable choice.

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Michael C. Laskowski, Christopher S. Shaw. 2015-05-08. Definable choice for a class of weakly o-minimal theories. https://doi.org/10.1007/s00153-016-0490-y

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