English

Weakly o-minimal types

Logic 2026-02-24 v3

Abstract

We introduce and study weak o-minimality in the context of complete types in an arbitrary first-order theory. A type pS(A)p\in S(A) is weakly o-minimal if for some relatively AA-definable linear order, <<, on p(C)p(\mathfrak{C}) every relatively LCL_{\mathfrak{C}}-definable subset of p(C)p(\mathfrak{C}) has finitely many convex components in (p(C),<)(p(\mathfrak{C}),<). We establish many nice properties of weakly o-minimal types. For example, we prove that weakly o-minimal types are dp-minimal and share several properties of weight-one types in stable theories, and that a version of monotonicity theorem holds for relatively definable functions on the locus of a weakly o-minimal type.

Keywords

Cite

@article{arxiv.2404.08260,
  title  = {Weakly o-minimal types},
  author = {Slavko Moconja and Predrag Tanović},
  journal= {arXiv preprint arXiv:2404.08260},
  year   = {2026}
}
R2 v1 2026-06-28T15:52:11.582Z