English

A realization theorem for sets of distances

Commutative Algebra 2017-01-19 v2

Abstract

Let HH be an atomic monoid. The set of distances Δ(H)\Delta (H) of HH is the set of all dNd \in \mathbb{N} with the following property: there are irreducible elements u_1,,u_k,v_1,v_k+du\_1, \ldots, u\_k, v\_1 \ldots, v\_{k+d} such that u_1u_k=v_1v_k+du\_1 \cdot \ldots \cdot u\_k=v\_1 \cdot \ldots \cdot v\_{k+d} but u_1u_ku\_1 \cdot \ldots \cdot u\_k cannot be written as a product of \ell irreducible elements for any N\ell \in \mathbb{N} with k<<k+dk\lt \ell \lt k+d. It is well-known (and easy to show) that, if Δ(H)\Delta (H) is nonempty, then minΔ(H)=gcdΔ(H)\min \Delta (H) = \gcd \Delta (H). In this paper we show conversely that for every finite nonempty set ΔN\Delta \subset \mathbb{N} with minΔ=gcdΔ\min \Delta = \gcd \Delta there is a finitely generated Krull monoid HH such that Δ(H)=Δ\Delta (H)=\Delta.

Keywords

Cite

@article{arxiv.1608.06407,
  title  = {A realization theorem for sets of distances},
  author = {Alfred Geroldinger and Wolfgang Schmid},
  journal= {arXiv preprint arXiv:1608.06407},
  year   = {2017}
}

Comments

Revised version. To appear in Journal of Algebra

R2 v1 2026-06-22T15:27:27.175Z