English

On limit models and parametrized noetherian rings

Rings and Algebras 2025-01-30 v4 Logic

Abstract

We study limit models in the abstract elementary class of modules with embeddings as algebraic objects. We characterize parametrized noetherian rings using the degree of injectivity of certain limit models. We show that the number of limit models and how close a ring is from being noetherian are inversely proportional. Theorem.\textbf{Theorem.} Let n0n \geq 0 The following are equivalent. 1. RR is left (<n)(<\aleph_{n } )-noetherian but not left (<n1)(< \aleph_{n -1 })-noetherian. 2.The abstract elementary class of modules with embeddings has exactly n+1n +1 non-isomorphic λ\lambda-limit models for every λ(card(R)+0)+\lambda \geq (\operatorname{card}(R) + \aleph_0)^+ such that the class is stable in λ\lambda. We further show that there are rings such that the abstract elementary class of modules with embeddings has exactly κ\kappa non-isomorphic λ\lambda-limit models for every infinite cardinal κ\kappa.

Keywords

Cite

@article{arxiv.2405.20214,
  title  = {On limit models and parametrized noetherian rings},
  author = {Marcos Mazari-Armida},
  journal= {arXiv preprint arXiv:2405.20214},
  year   = {2025}
}

Comments

13 pages

R2 v1 2026-06-28T16:47:26.492Z