English

The class of Gorenstein injective modules is covering if and only if it is closed under direct limits

Commutative Algebra 2024-09-18 v2

Abstract

We prove that the class of Gorenstein injective modules, GI\mathcal{GI}, is special precovering if and only if it is covering if and only if it is closed under direct limits. This adds to the list of examples that support Enochs' conjecture:\\ "Every covering class of modules is closed under direct limits".\\ We also give a characterization of the rings for which GI\mathcal{GI} is covering: the class of Gorenstein injective left RR-modules is covering if and only if RR is left noetherian, and such that character modules of Gorenstein injective left RR modules are Gorenstein flat.

Keywords

Cite

@article{arxiv.2403.02493,
  title  = {The class of Gorenstein injective modules is covering if and only if it is closed under direct limits},
  author = {Alina Iacob},
  journal= {arXiv preprint arXiv:2403.02493},
  year   = {2024}
}