English

Approximation by $O$-minimal sets in power-bounded $T$-convex valued fields

Logic 2018-12-11 v1

Abstract

We show that, for a certain large class of power-bounded oo-minimal LT\mathcal{L}_T-theories TT whose field of exponents is infinite-dimensional as a vector space over the rationals, any definable set in a TT-convex valued field (R,O)(\mathcal{R}, \mathfrak{O}) is in a precise sense the limit of a family of LT\mathcal{L}_T-definable sets indexed over the residue field. Alternatively, in the mainstream model-theoretic language, this says that if (R,O)(\mathcal{R}', \mathfrak{O}') is an elementary substructure of (R,O)(\mathcal{R}, \mathfrak{O}) and if the residue field of O\mathfrak{O} contains an element that is infinitesimal relative to the residue field of O\mathfrak{O}' then any set A(R)mA \subseteq (\mathcal{R}')^m definable in (R,O)(\mathcal{R}', \mathfrak{O}') is the trace of a set definable in R\mathcal{R}.

Keywords

Cite

@article{arxiv.1812.03590,
  title  = {Approximation by $O$-minimal sets in power-bounded $T$-convex valued fields},
  author = {Yimu Yin},
  journal= {arXiv preprint arXiv:1812.03590},
  year   = {2018}
}
R2 v1 2026-06-23T06:36:58.057Z