English

Numerical aspects of complexes of finite homological dimensions

Commutative Algebra 2023-05-23 v1

Abstract

Let (R,\fm)(R,\fm) be a local ring, and let CC be a semidualizing complex. We establish the equality rR(Z)=ν(\ExtRginfC(Z,C))μR\depthC(m,C)r_R(Z) = \nu(\Ext^{g-\inf C}_R(Z,C))\mu^{\depth C}_R(\mathfrak{m}, C) for a homologically finite and bounded complex ZZ with finite \GC\GC-dimension gg. Additionally, we prove that if \Exti(M,N)=0\Ext^i(M,N)=0 for sufficiently large ii, while \idR\Exti(M,N)\id_R\Ext^i(M,N) remains finite for all ii, then both \pdRM\pd_R M and \idRN\id_R N are finite when MM and NN are finitely generated RR-modules. These findings extend the recent results of Ghosh and Puthenpurakal \cite{Ghosh}, addressing their questions as presented in \cite[Question 3.9]{Ghosh} and \cite[Question 4.2]{Ghosh}.

Keywords

Cite

@article{arxiv.2305.12251,
  title  = {Numerical aspects of complexes of finite homological dimensions},
  author = {Majid Rahro Zargar and Mohsen Gheibi},
  journal= {arXiv preprint arXiv:2305.12251},
  year   = {2023}
}

Comments

arXiv admin note: text overlap with arXiv:2305.10244