arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0712.1328math.RAmath.RT
收藏

无挠模何时是投射模?

When Are Torsionless Modules Projective?

Rong Luo, Zhaoyong Huang

摘要:

本文研究了一个无挠生成模是投射模时的问题。设$Λ$是根式平方为零的Artin局部代数.则一个无挠生成的$Λ$ -模$M$是投射的,如果${\rm Ext^1_Λ}(M,M)=0$ .对于交换的Artin环$Λ$,若满足下列条件,则一个无挠生成的$Λ$ -模$M$是投射的:(1)对于$i=1,2,3$是${\rm Ext}^i_Λ(M,Λ)=0$;(2)对于$i=1,2$是${\rm Ext}^i_Λ(M,M)=0$.作为这个结果的一个推论,我们得到:对于交换Artin环$Λ$,一个生成的Gorenstein投射$Λ$ -模是投射的当且仅当它是自正交的.

英文摘要:

In this paper, we study the problem when a finitely generated torsionless module is projective. Let $Λ$ be an Artinian local algebra with radical square zero. Then a finitely generated torsionless $Λ$-module $M$ is projective if ${\rm Ext^1_Λ}(M,M)=0$. For a commutative Artinian ring $Λ$, a finitely generated torsionless $Λ$-module $M$ is projective if the following conditions are satisfied: (1) ${\rm Ext}^i_Λ(M,Λ)=0$ for $i=1,2,3$; and (2) ${\rm Ext}^i_Λ(M,M)=0$ for $i=1,2$. As a consequence of this result, we have that for a commutative Artinian ring $Λ$, a finitely generated Gorenstein projective $Λ$-module is projective if and only if it is selforthogonal.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑