English

A new ultrafilter proof of Van der Waerden's theorem

Logic 2026-03-05 v1 Combinatorics

Abstract

We present a new short proof of Van der Waerden's Theorem about the existence of arbitrarily long monochromatic arithmetic progressions. The proof uses algebra in the compact space of ultrafilters βN\beta\N, but contrarily to the other existing proofs, neither minimal nor idempotent ultrafilters are involved.

Keywords

Cite

@article{arxiv.2603.04043,
  title  = {A new ultrafilter proof of Van der Waerden's theorem},
  author = {Mauro Di Nasso},
  journal= {arXiv preprint arXiv:2603.04043},
  year   = {2026}
}