Decidability and Computability of Certain Torsion-Free Abelian Groups

Autor:	Rodney G. Downey, Daniel Turetsky, Oleg V. Kudinov, Alexander G. Melnikov, Asher M. Kach, Sergei S. Goncharov, Julia F. Knight
Jazyk:	angličtina
Rok vydání:	2010
Předmět:	Discrete mathematics Torsion subgroup coding in groups Logic Metabelian group Elementary abelian group Rank of an abelian group Non-abelian group Free abelian group 03D45 Solvable group Abelian group completely decomposable torsion-free abelian groups Mathematics
Zdroj:	Notre Dame J. Formal Logic 51, no. 1 (2010), 85-96
Popis:	We study completely decomposable torsion-free abelian groups of the form $\mathcal{G}_S := \oplus_{n \in S} \mathbb{Q}_{p_n}$ for sets $S \subseteq \omega$ . We show that $\mathcal{G}_S$ has a decidable copy if and only if S is $\Sigma^0_2$ and has a computable copy if and only if S is $\Sigma^0_3$ .
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::920987f5e72fadde87e0ff74e7f8efa9 http://projecteuclid.org/euclid.ndjfl/1273002111 Zobrazit plný text záznamu