English

Integral closure and local cohomology

Commutative Algebra 2024-04-08 v1

Abstract

Let AA be a Noetherian ring and let II be an ideal in AA. Let F={Jn}n0\mathcal{F} = \{ J_n \}_{n \geq 0} be a multiplicative filtration of ideals in AA such that R(F)=n0Jn\mathcal{R}(\mathcal{F}) = \bigoplus_{n \geq 0} J_n is a finitely generated AA-algebra. Let R=A[It]\mathcal{R} = A[It] and assume InJnI^n \subseteq J_n for all n1n \geq 1. We show the following two assertions are equivalent: (1) For all i0i \geq 0 we have HR+i(R(F))n=0H^i_{\mathcal{R}_+}(\mathcal{R}(\mathcal{F}))_n = 0 for all n0n \gg 0. (2) JnInJ_n \subseteq \overline{I^n} for all n1n \geq 1. Here In\overline{I^n} is the integral closure of InI^n.

Keywords

Cite

@article{arxiv.2404.03841,
  title  = {Integral closure and local cohomology},
  author = {Tony J. Puthenpurakal},
  journal= {arXiv preprint arXiv:2404.03841},
  year   = {2024}
}
R2 v1 2026-06-28T15:44:44.623Z