Coherent rings and absolutely pure precovers

被引:14
作者
Dai, Guocheng [1 ]
Ding, Nanqing [2 ]
机构
[1] Sichuan Normal Univ, Coll Math & Software Sci, Chengdu, Sichuan, Peoples R China
[2] Nanjing Univ, Dept Math, Nanjing 210093, Jiangsu, Peoples R China
基金
中国国家自然科学基金;
关键词
Absolutely pure module; coherent ring; direct limit; precovering class; ENVELOPES;
D O I
10.1080/00927872.2019.1595637
中图分类号
O1 [数学];
学科分类号
0701 ; 070101 ;
摘要
In this article, we prove that a precovering class is closed under direct limits provided that is closed under direct products and pure submodules. As a corollary, we get that a ring R is left coherent if and only if the class of absolutely pure left R-modules is a precovering class.
引用
收藏
页码:4743 / 4748
页数:6
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