English

The Module Structure of a Group Action on a Ring

Commutative Algebra 2024-05-15 v4 Representation Theory

Abstract

Consider a finite group GG acting on a graded Noetherian kk-algebra SS, for some field kk of characteristic pp; for example SS might be a polynomial ring. Regard SS as a kGkG-module and consider the multiplicity of a particular indecomposable module as a summand in each degree. We show how this can be described in terms of homological algebra and how it is linked to the geometry of the group action on the spectrum of SS.

Keywords

Cite

@article{arxiv.2205.03379,
  title  = {The Module Structure of a Group Action on a Ring},
  author = {Peter Symonds},
  journal= {arXiv preprint arXiv:2205.03379},
  year   = {2024}
}

Comments

Rewrote part of section 3 to clarify argument. Corrected calculations of examples in section 9

R2 v1 2026-06-24T11:09:39.922Z