English

On derived functors of graded local cohomology modules-II

Commutative Algebra 2020-10-28 v1

Abstract

Let R=K[X1,,Xn]R=K[X_1,\ldots, X_n] where KK is a field of characteristic zero, and let An(K)A_n(K) be the nthn^{th} Weyl algebra over KK. We give standard grading on RR and An(K)A_n(K). Let II, JJ be homogeneous ideals of RR. Let M=HIi(R)M = H^i_I(R) and N=HJj(R)N = H^j_J(R) for some i,ji, j. We show that \ExtAn(K)ν(M,N)\Ext_{A_n(K)}^{\nu}(M,N) is concentrated in degree zero for all ν0\nu \geq 0, i.e., \ExtAn(K)ν(M,N)l=0\Ext_{A_n(K)}^{\nu}(M,N)_l=0 for l0l \neq0. This proves a conjecture stated in part I of this paper.

Keywords

Cite

@article{arxiv.1906.00370,
  title  = {On derived functors of graded local cohomology modules-II},
  author = {Tony J. Puthenpurakal and Sudeshna Roy and Jyoti Singh},
  journal= {arXiv preprint arXiv:1906.00370},
  year   = {2020}
}