Autor:	Laskowski, Michael C., Ulrich, Danielle S.
Rok vydání:	2022
Předmět:	Mathematics - Logic Mathematics - Commutative Algebra 03E15 13C05
Druh dokumentu:	Working Paper
Popis:	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.
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/2209.06898 Zobrazit plný text záznamu View this record from Arxiv