Cofiniteness of local cohomology modules for a pair of ideals for small dimensions

被引:7
作者
Aghapournahr, Moharram [1 ]
机构
[1] Arak Univ, Dept Math, Fac Sci, Arak 3815688349, Iran
关键词
Local cohomology; FD <=(n) modules; cofinite modules; ETH-cofinite modules; PRIMES; ARTINIANNESS; CATEGORY; RESPECT;
D O I
10.1142/S0219498818500202
中图分类号
O29 [应用数学];
学科分类号
070104 ;
摘要
Let R be a commutative Noetherian ring, I and J be two ideals of R and M be an R-module (not necessary I-torsion). In this paper among other things, it is shown that if dim M <= 1, then the R-module Ext(R)(i) (R/I, M) is finitely generated, for all i >= 0, if and only if the R-module Ext(R)(i) (R/I, M) is finitely generated, for i = 0, 1. As a consequence, we prove that if M is finitely generated and t is an element of N such that the R-module H-I, J(i) (M) is FD <= 1 (or weakly Laskerian) for all i < t, then H-I, J(i) (M) is (I, J)-cofinite for all i < t and for any FD <= 0 (or minimax) submodule N of H-I, J(t) (M), the R-modules Hom(R) (R/I, H-I, J(t) (M)/N) and Ext(R)(1) (R/I, H-I, J(t) (M)/N) are finitely generated. Also it is shown that if dim M/aM <= 1 (e.g. dim R/a <= 1) for all a is an element of (W) over tilde (I, J), then the local cohomology module H-I, J(i) (M) is (I, J)-cofinite for all i >= 0.
引用
收藏
页数:12
相关论文
共 37 条
[1]   Cofiniteness and Artinianness of certain local cohomology modules [J].
Aghapournahr M. ;
Ahmadi-amoli K. ;
Sadeghi M.Y. .
Ricerche di Matematica, 2016, 65 (1) :21-36
[2]  
Aghapournahr M, 2014, B MATH SOC SCI MATH, V57, P347
[3]   A natural map in local cohomology [J].
Aghapournahr, Moharram ;
Melkersson, Leif .
ARKIV FOR MATEMATIK, 2010, 48 (02) :243-251
[4]   A generalization of the cofiniteness problem in local cohomology modules [J].
Asadollahi, J ;
Khashyarmanesh, K ;
Salarian, S .
JOURNAL OF THE AUSTRALIAN MATHEMATICAL SOCIETY, 2003, 75 :313-324
[5]   On the cofiniteness of local cohomology modules [J].
Bahmanpour, Kamal ;
Naghipour, Reza .
PROCEEDINGS OF THE AMERICAN MATHEMATICAL SOCIETY, 2008, 136 (07) :2359-2363
[6]  
Bahmanpour K, 2014, MATH SCAND, V115, P62
[7]   ON THE CATEGORY OF COFINITE MODULES WHICH IS ABELIAN [J].
Bahmanpour, Kamal ;
Naghipour, Reza ;
Sedghi, Monireh .
PROCEEDINGS OF THE AMERICAN MATHEMATICAL SOCIETY, 2014, 142 (04) :1101-1107
[8]   Cofiniteness of local cohomology modules for ideals of small dimension [J].
Bahmanpour, Kamal ;
Naghipour, Reza .
JOURNAL OF ALGEBRA, 2009, 321 (07) :1997-2021
[9]   Finiteness properties for Matlis reflexive modules [J].
Belshoff, R ;
Slattery, SP ;
Wickham, C .
COMMUNICATIONS IN ALGEBRA, 1996, 24 (04) :1371-1376
[10]   The local cohomology modules of Matlis reflexive modules are almost cofinite [J].
Belshoff, R ;
Slattery, SP ;
Wickham, C .
PROCEEDINGS OF THE AMERICAN MATHEMATICAL SOCIETY, 1996, 124 (09) :2649-2654