English

Reduced rank in $\sigma[M]$

Rings and Algebras 2026-01-26 v3

Abstract

Using the concept of prime submodule introduced by Raggi et.al. we extend the notion of reduced rank to the module-theoretic context of σ[M]\sigma[M]. We study the quotient category of σ[M]\sigma[M] modulo the hereditary torsion theory cogenerated by the MM-injective hull of MM, when MM is a semiprime Goldie module. We prove that this quotient category is spectral. We then consider the hereditary torsion theory in σ[M]\sigma[M] cogenerated by the MM-injective hull of M/L(M)M/\mathfrak{L}(M), where L(M)\mathfrak{L}(M) is the prime radical of MM, and we determine when the module of quotients of MM, with respect to this torsion theory, has finite length in the quotient category. Finally, we give conditions on a module MM with endomorphism ring SS under which SS is an order in an Artinian ring, extending Small's Theorem.

Keywords

Cite

@article{arxiv.2201.07196,
  title  = {Reduced rank in $\sigma[M]$},
  author = {John A. Beachy and Mauricio Medina-Bárcenas},
  journal= {arXiv preprint arXiv:2201.07196},
  year   = {2026}
}

Comments

21 pages, second version. Last version had some mistakes in Section 3. We correct them and added new results

R2 v1 2026-06-24T08:54:17.139Z