English

Graded components of local cohomology modules over invariant rings-II

Commutative Algebra 2018-08-22 v2

Abstract

Let AA be a regular ring containing a field KK of characteristic zero and let R=A[X1,,Xm]R = A[X_1,\ldots, X_m]. Consider RR as standard graded with degA=0\deg A = 0 and degXi=1\deg X_i = 1 for all ii. Let GG be a finite subgroup of GLm(A)GL_m(A). Let GG act linearly on RR fixing AA. Let S=RGS = R^G. In this paper we present a comprehensive study of graded components of local cohomology modules HIi(S)H^i_I(S) where II is an \emph{arbitrary} homogeneous ideal in SS. We prove stronger results when GGLm(K)G \subseteq GL_m(K). Some of our results are new even in the case when AA is a field.

Keywords

Cite

@article{arxiv.1712.09197,
  title  = {Graded components of local cohomology modules over invariant rings-II},
  author = {Tony J. Puthenpurakal},
  journal= {arXiv preprint arXiv:1712.09197},
  year   = {2018}
}

Comments

Better bounds obtained. A proposition corrected. Many typo's corrected