English

Generalizing a theorem of B\`{e}s and Choffrut

Logic 2020-02-26 v1

Abstract

B\`{e}s and Choffrut recently showed that there are no intermediate structures between (R,<,+)(\mathbb{R},<,+) and (R,<,+,Z)(\mathbb{R},<,+,\mathbb{Z}). We prove a generalization: if R\mathcal{R} is an o-minimal expansion of (R,<,+)(\mathbb{R},<,+) by bounded subsets of Euclidean space then there are no intermediate structures between R\mathcal{R} and (R,Z)(\mathcal{R},\mathbb{Z}). It follows there are no intermediate structures between (R,<,+,sin[0,2π])(\mathbb{R},<,+,\sin|_{[0,2\pi]}) and (R,<,+,sin)(\mathbb{R},<,+,\sin).

Cite

@article{arxiv.2002.10508,
  title  = {Generalizing a theorem of B\`{e}s and Choffrut},
  author = {Erik Walsberg},
  journal= {arXiv preprint arXiv:2002.10508},
  year   = {2020}
}

Comments

8 pages. Comments are welcome

R2 v1 2026-06-23T13:52:16.093Z