English

Betweenness of partial orders

Logic in Computer Science 2020-04-22 v1

Abstract

We construct a monadic second-order sentence that characterizes the ternary relations that are the betweenness relations of finite or infinite partial orders. We prove that no first-order sentence can do that. We characterize the partial orders that can be reconstructed from their betweenness relations. We propose a polynomial time algorithm that tests if a finite relation is the be-tweenness of a partial order.

Keywords

Cite

@article{arxiv.2004.09777,
  title  = {Betweenness of partial orders},
  author = {Bruno Courcelle},
  journal= {arXiv preprint arXiv:2004.09777},
  year   = {2020}
}
R2 v1 2026-06-23T14:59:16.364Z