$\mathcal{S}$-minimaxness and local-global principle of local cohomology Modules

Document Type : Research Paper

Author

Department of Mathematics, Faculty of Science, Payame Noor University (PNU), Tehran, Iran

Abstract

Let $R$ be a commutative Noetherian ring, Let $\mathcal{S}$ be a Serre subcategory of the category of $R$-modules, $M$ a finitely generated $R$-module and $\frak{a}$, $\frak{b}$  two ideals of $R$ such that $\frak{b}\subseteq\frak{a}$. By using the concept of $\mathcal{S}$-minimax modules w ve define $\mathcal{S}^{\frak{b}}$-minimaxness dimension $\mathcal{S}_{\frak{a}}^{\frak{b}}(M)$ of $M$ relative to $\frak{a}$ by  $\mathcal{S}_{\frak{a}}^{\frak{b}}(M):=\inf \lbrace i\in \mathbb{N}_{0} : \frak{b}^t\text{H}_{\frak{a}}^{i}(M)  \text{ is not } \mathcal{S} -\text{minimax} \text{ for all } t\in \mathbb{N} \rbrace$. Also, we say that the local global principle for the $\mathcal{S}$-minimaxness of local cohomology modules holds at level $r$ if, for every choice of ideals $\frak{a}$, $\frak{b}$ of $R$ with $\frak{b}\subseteq \frak{a}$ and for every choice of finitely generated $R$-module $M$, it is the case that $\mathcal{S}_{\frak{a}}^{\frak{b}}(M)>r\Leftrightarrow f_{\frak{a} R_{\frak{p}}}^{\frak{b} R_{\frak{p}}}(M_{\frak{p}})>r \text{ for all } {\frak{p}} \in \lbrace {\frak{p}} \in\text{Spec}(R)\vert R/{\frak{p}} \notin \mathcal{S}\rbrace$. In this paper, we investigate the local-global principle concerning the $\mathcal{S}$-minimaxness of local cohomology modules. Among other things, we will show that this principle holds at level 1 over an arbitrary commutative Noetherian ring $R$ and at all levels whenever $\dim R \leq 2$. Then by using the obtained results for some specific Serre classes of $R$-modules we get some main results concerning the local global principle of local cohomology modules.

Keywords


[1] M. Aghapournahr and L. Melkersson, Local cohomology and Serre subcategories, J. Algebra, 320 (2008) 1275-1287.
[2] D. Asadollahi and R. Naghipour, Faltings’ local-global principle for the finiteness of local cohomology modules, Comm. Algebra, 43 (2015) 953-958.
[3] K. Bahmanpour, R. Naghipour and M. Sedghi, Minimaxness and cofiniteness properties of local cohomology modules, Comm. Algebra, 41 (2013) 2799-2814.
[4] M. P. Brodmann, Ch. Rotthaus and R. Y. Sharp, On annihilators and associated primes of local cohomology modules, J. Pure Appl. Algebra., 153 (2000) 197-227.
[5] M. Brodmann and R. Y. Sharp, Local Cohomology: An Algebraic Introduction with Geometric Applications, Cambridge University Press, United Kingdom, 1998.
[6] N. T. Cuong, S. Goto and N. V. Hoang, On the cofiniteness of generalized local cohomology modules, Kyoto J. Math., 55 (2015) 169-185.
[7] M. T. Dibaei and S. Yassemi, Associated primes and cofiniteness of local cohomology modules, Manuscripta math., 117 No. 2 (2005) 199-205.
[8] M. R. Doustimehr and R. Naghipour, Faltings’ local-global principle for the minimaxness of local cohomology modules over noetherian rings, Comm. Algebra, 43 (2015) 400-411.
[9] M. R. Doustimehr and R. Naghipour, On the generalization of Faltings’ Annihilator Theorem, Arch. Math., 102 (2014) 15-23.
[10] K. I. Kawasaki, Cofiniteness of local cohomology modules for principal ideals, Bull. London Math. Soc., 30 (1998) 241-246.
[11] H. Matsumura, Commutative Ring Theory, Cambridge University Press, 1986.
[12] L. Melkersson, Modules cofinite with repect to an ideal, J. Algebra, 285 (2005) 649-668.
[13] R. Naghipour, R. Maddahali, and Kh. A. Amoli, Faltings’ local-global principle for the indimension, Comm. Algebra, 46 (2018) 3496-3509.
[14] Sh. Rezaei, S-minimaxness and local cohomology modules, Archiv der math., 110 (2018) 563-572.
[15] P. H. Quy, On the finiteness of associated primes of local cohomology modules, Proc. Amer. Math. Soc., 138 (2010) 1965-1968.