English

Rings whose indecomposable modules are pure-projective or pure-injective

Rings and Algebras 2025-07-08 v2

Abstract

Let P\mathcal{P} be the class of rings for which every indecomposable right module is pure-projective or pure-injective. When RR is a Noetherian local commutative ring of maximal ideal PP, it is proven that RPR\in\mathcal{P} if and only if RR is either an artinian valuation ring or a discrete valuation domain of rank one with rank(R~\widetilde{R})2\leq 2 where R~\widetilde{R} is the completion of RR in its PP-adic topology. Let RR be a commutative ring. Then RPR\in\mathcal{P} if and only if RR is a clean arithmetical ring with RPPR_P\in\mathcal{P} for each maximal ideal PP of RR. Moreover, RR is a semi-perfect ring when it is Noetherian. Some examples of commutative rings of the class P\mathcal{P} are given.

Keywords

Cite

@article{arxiv.1108.5707,
  title  = {Rings whose indecomposable modules are pure-projective or pure-injective},
  author = {François Couchot},
  journal= {arXiv preprint arXiv:1108.5707},
  year   = {2025}
}
R2 v1 2026-06-21T18:56:31.256Z