English

On Noether's and Weyl's bound in positive characteristic

Representation Theory 2007-05-23 v2 Commutative Algebra

Abstract

In this note we generalize several well known results concerning invariants of finite groups from characteristic zero to positive characteristic not dividing the group order. The first is Schmid's relative version of Noether's theorem. That theorem compares the degrees of generators of a group with those of a subgroup. Then we prove a suitable positive characteristic version of Weyl's theorem on vector invariants: polarization works in small degrees. Using that we show that the regular representation has the "most general" ring of invariants, thereby generalizing theorems of Schmid and Smith.

Keywords

Cite

@article{arxiv.math/0207194,
  title  = {On Noether's and Weyl's bound in positive characteristic},
  author = {Friedrich Knop},
  journal= {arXiv preprint arXiv:math/0207194},
  year   = {2007}
}

Comments

16 pages, v2: minor changes, final version

R2 v1 2026-07-22T16:46:45.133Z