Abstract
We show that for every computable ordinal of the form , where is zero or a limit ordinal and , there exists a torsion-free abelian group having an -computable copy if and only if is nonlow.
Citation
Alexander G. Melnikov. "New Degree Spectra of Abelian Groups." Notre Dame J. Formal Logic 58 (4) 507 - 525, 2017. https://doi.org/10.1215/00294527-2017-0006
Information