Borel complexity of modules
Abstract
We prove that for a countable, commutative ring $R$, the class of countable $R$-modules either has only countably many isomorphism types, or else it is Borel complete. The machinery gives a succinct proof of the Borel completeness of TFAB, the class of torsion-free abelian groups. We also prove that for any countable ring $R$, both the class of left $R$-modules endowed with an endomorphism and the class of left $R$-modules with four named submodules are Borel complete.
Fields of Study & Subjects
Computability
Logic
AI Algorithms
Rings
Modules
and Algebras
Advanced Topology and Set Theory
Publication details
- Journal / source
- Annals of Pure and Applied Logic
- Publisher
- Elsevier BV
- Volume
- 177
- Issue
- 9
- Pages
- 103780–103780
- Publication date
- 29 April 2026
- Language
- EN