The classification of torsion-free abelian groups of finite rank up to isomorphism and up to quasi-isomorphism
arXiv:0902.1218 · doi:10.1090/S0002-9947-2011-05349-3
Abstract
The isomorphism and quasi-isomorphism relations on the -local torsion-free abelian groups of rank are incomparable with respect to Borel reducibility.
This is a part of my doctoral thesis. 23 pages, 1 figure