English

Graded-irreducible modules are irreducible

Commutative Algebra 2016-10-03 v2

Abstract

We show that if a graded submodule of a Noetherian module cannot be written as a proper intersection of graded submodules, then it cannot be written as a proper intersection of submodules at all. More generally, we show that a natural extension of the index of reducibility to the graded setting coincides with the ordinary index of reducibility. We also investigate the question of uniqueness of the components in a graded-irreducible decomposition, as well as the relation between the index of reducibility of a non-graded ideal and that of its largest graded subideal.

Keywords

Cite

@article{arxiv.1508.07518,
  title  = {Graded-irreducible modules are irreducible},
  author = {Justin Chen and Youngsu Kim},
  journal= {arXiv preprint arXiv:1508.07518},
  year   = {2016}
}

Comments

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R2 v1 2026-06-22T10:44:28.837Z