English

Separating invariants for multisymmetric polynomials

Representation Theory 2021-11-16 v2 Commutative Algebra Rings and Algebras

Abstract

This article studies separating invariants for the ring of multisymmetric polynomials in mm sets of nn variables over an arbitrary field K\mathbb{K}. We prove that in order to obtain separating sets it is enough to consider polynomials that depend only on n2+1\lfloor \frac{n}{2} \rfloor + 1 sets of these variables. This improves a general result by Domokos about separating invariants. In addition, for n4n \leq 4 we explicitly give minimal separating sets (with respect to inclusion) for all mm in case char(K)=0\text{char}(\mathbb{K}) = 0 or char(K)>n\text{char}(\mathbb{K}) > n.

Keywords

Cite

@article{arxiv.1911.04850,
  title  = {Separating invariants for multisymmetric polynomials},
  author = {Artem Lopatin and Fabian Reimers},
  journal= {arXiv preprint arXiv:1911.04850},
  year   = {2021}
}

Comments

12 pages, accepted for publication in Proc AMS

R2 v1 2026-06-23T12:12:58.469Z