English

Semi-linear stars are contractible

Logic 2019-10-02 v2

Abstract

Let R\cal R be an ordered vector space over an ordered division ring. We prove that every definable set XX is a finite union of relatively open definable subsets which are definably simply-connected, settling a conjecture from [5]. The proof goes through the stronger statement that the star of a cell in a special linear decomposition of XX is definably simply-connected. In fact, if the star is bounded, then it is definably contractible.

Keywords

Cite

@article{arxiv.1604.07329,
  title  = {Semi-linear stars are contractible},
  author = {Pantelis E. Eleftheriou},
  journal= {arXiv preprint arXiv:1604.07329},
  year   = {2019}
}
R2 v1 2026-06-22T13:40:18.978Z