On the intersection of Annihilator of the Valabrega-Valla module
Commutative Algebra
2013-02-07 v1
Abstract
Let (A,\m) be a \CM \ local ring with an infinite residue field and let I be an \m-primary ideal. Let \bx=x1,…,xr be a A-superficial sequence \wrt \ I. Set \VcI(\bx)=n≥1⨁\bxInIn+1∩(\bx). A consequence of a theorem due to Valabrega and Valla is that \VcI(\bx)=0 \ff \ the initial forms x1∗,…,xr∗ is a GI(A) regular sequence. Furthermore this holds if and only if \depthGI(A)≥r. We show that if \depthGI(A)<r then \afr(I)=\bx=x1,…,xr is aA-superficial sequence w.r.t I⋂\annA\VcI(\bx) is \m-primary. Suprisingly we also prove that under the same hypotheses, n≥1⋂\afr(In) is also \m-primary.
Cite
@article{arxiv.1302.1307,
title = {On the intersection of Annihilator of the Valabrega-Valla module},
author = {Tony J. Puthenpurakal},
journal= {arXiv preprint arXiv:1302.1307},
year = {2013}
}