The classification of torsion-free abelian groups of finite rank up to isomorphism and up to quasi-isomorphism

Coskey, Samuel

doi:10.1090/S0002-9947-2011-05349-3

The classification of torsion-free abelian groups of finite rank up to isomorphism and up to quasi-isomorphism
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Trans. Amer. Math. Soc. 364 (2012), 175-194 Request permission

Abstract:

The isomorphism and quasi-isomorphism relations on the $p$-local torsion-free abelian groups of rank $n\geq 3$ are incomparable with respect to Borel reducibility.

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