中文

纤维积上 Ext 与 Tor 的消没

交换代数 2016-04-22 v3

摘要

考虑具有公共剩余域 kk 的局部环 SSTT 的非平凡纤维积 R=S×kTR=S\times_kT。给定两个有限生成 RR-模 MMNN,我们证明如果对于某个 i5i\geq 5ToriR(M,N)=0=Tori+1R(M,N)\operatorname{Tor}^R_i(M,N)=0=\operatorname{Tor}^R_{i+1}(M,N),则 pdR(M)1\operatorname{pd}_R(M)\leq 1pdR(N)1\operatorname{pd}_R(N)\leq 1。由此,我们推导出若干结论,例如 RR 满足 Auslander-Reiten 猜想。

关键词

引用

@article{arxiv.1603.05711,
  title  = {Vanishing of Ext and Tor over fiber products},
  author = {Saeed Nasseh and Sean Sather-Wagstaff},
  journal= {arXiv preprint arXiv:1603.05711},
  year   = {2016}
}

备注

13 pages. comments welcome. v.2 includes section about depth formula and minor other revisions. v.3 includes corrections to Lemmas 2.3-2.5