English

Reducing the dichromatic number via cycle reversions in infinite digraphs

Combinatorics 2020-07-22 v2

Abstract

We prove the following conjecture of S. Thomass\'e: for every (potentially infinite) digraph D D it is possible to iteratively reverse directed cycles in such a way that the dichromatic number of the final reorientation D D^{*} of D D is at most two and each edge is flipped only finitely many times. In addition, we guarantee that in every strong component of D D^{*} all the local edge-connectivities are finite and any edge is reversed at most twice.

Keywords

Cite

@article{arxiv.1909.00873,
  title  = {Reducing the dichromatic number via cycle reversions in infinite digraphs},
  author = {Paul Ellis and Attila Joó and Dániel T. Soukup},
  journal= {arXiv preprint arXiv:1909.00873},
  year   = {2020}
}

Comments

19 pages

R2 v1 2026-06-23T11:03:29.440Z