English

Bockstein cohomology of associated graded rings

Commutative Algebra 2013-08-30 v1

Abstract

Let (A,m)(A,\mathfrak{m}) be a Cohen-Macaulay local ring of dimension dd and let II be an m\mathfrak{m}-primary ideal. Let GG be the associated graded ring of AA \wrt \ II and let R=A[It,t1]\R = A[It,t^{-1}] be the extended Rees ring of AA with respect to II. Notice t1t^{-1} is a non-zero divisor on R\R and R/t1R=G\R/t^{-1}\R = G. So we have \textit{Bockstein operators} βi ⁣:HG+i(G)(1)\rtHG+i+1(G)\beta^i \colon H^i_{G_+}(G)(-1) \rt H^{i+1}_{G_+}(G) for i0i \geq 0. Since βi+1(+1)βi=0\beta^{i+1}(+1)\circ \beta^i = 0 we have \textit{Bockstein cohomology} modules BHi(G)BH^i(G) for i=0,,di = 0,\ldots,d. In this paper we show that certain natural conditions on II implies vanishing of some Bockstein cohomology modules.

Keywords

Cite

@article{arxiv.1308.6428,
  title  = {Bockstein cohomology of associated graded rings},
  author = {Tony J. Puthenpurakal},
  journal= {arXiv preprint arXiv:1308.6428},
  year   = {2013}
}