Every class of $S$-acts having a flatness property is closed under directed colimits

Authors

  • H. Qiao College of Mathematics and Statistics, Northwest Normal University, Lanzhou 730070, Gansu, P. R. China.
  • L. Wang College of Mathematics and Statistics, Northwest Normal University, Lanzhou 730070, Gansu, P. R. China.
  • X. Ma College of Mathematics and Statistics, Northwest Normal University, Lanzhou 730070, Gansu, P. R. China.
Abstract:

Let $S$ be a monoid. In this paper, we prove every class of $S$-acts having a flatness property is closed underdirected colimits, it extends some known results. Furthermore thisresult implies that every $S$-act has a flatness cover if and only if it has a flatness precover.

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Journal title

volume 42  issue 2

pages  341- 351

publication date 2016-04-01

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