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THE COMPLEXITY OF THE EMBEDDABILITY RELATION BETWEEN TORSION-FREE ABELIAN GROUPS OF UNCOUNTABLE SIZE

Published online by Cambridge University Press:  01 August 2018

FILIPPO CALDERONI*
Affiliation:
DIPARTIMENTO DI MATEMATICA «GIUSEPPE PEANO» UNIVERSITÀ DI TORINO VIA CARLO ALBERTO 10, 10123 TORINO, ITALYE-mail:filippo.calderoni@unito.it

Abstract

We prove that for every uncountable cardinal κ such that κ = κ, the quasi-order of embeddability on the κ-space of κ-sized graphs Borel reduces to the embeddability on the κ-space of κ-sized torsion-free abelian groups. Then we use the same techniques to prove that the former Borel reduces to the embeddability relation on the κ-space of κ-sized R-modules, for every $\mathbb{S}$-cotorsion-free ring R of cardinality less than the continuum. As a consequence we get that all the previous are complete $\Sigma _1^1$ quasi-orders.

Type
Articles
Copyright
Copyright © The Association for Symbolic Logic 2018 

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References

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