English

Reflexive modules, self-dual modules and Arf rings

Commutative Algebra 2021-05-27 v1 Algebraic Geometry Rings and Algebras

Abstract

We prove a tight connection between reflexive modules over a one-dimensional ring RR and its birational extensions that are self-dual as RR-modules. Consequently, we show that a complete local reduced Arf ring has finitely many indecomposable reflexive modules up to isomorphism, which can be represented precisely by the local rings infinitely near it. We also characterize Arf rings by the property that any reflexive module is self-dual. We give applications on dimension of subcategories and existence of endomorphism rings of small global dimension (non-commutative desingularizations). Our results indicate striking similarities between Arf rings in dimension one and rational singularities in dimension two from representation-theoretic and categorical perspectives.

Keywords

Cite

@article{arxiv.2105.12240,
  title  = {Reflexive modules, self-dual modules and Arf rings},
  author = {Hailong Dao},
  journal= {arXiv preprint arXiv:2105.12240},
  year   = {2021}
}
R2 v1 2026-06-24T02:28:03.031Z