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Jump degrees of torsion-free abelian groups

Published online by Cambridge University Press:  12 March 2014

Brooke M. Andersen ,
Asher M. Kach ,
Alexander G. Melnikov  and
Reed Solomon
Brooke M. Andersen
Affiliation:
Department of Mathematics and Computer Science, Assumption College, Worcester, MA 01609-1296, USA, E-mail: brandersen@assumption.edu
Asher M. Kach
Affiliation:
Department of Mathematics, University of Chicago, Chicago, IL 60637, USA, E-mail: kach@math.uchicago.edu, E-mail: asher.kach@gmail.com
Alexander G. Melnikov
Affiliation:
Department of Computer Science, University of Auckland, Auckland 1142, New Zealand, E-mail: a.melnikov@cs.auckland.ac.nz, E-mail: alexander.g.melnikov@gmail.com
Reed Solomon
Affiliation:
Department of Mathematics, University of Connecticut, Storrs, CT 06269-3009, USA, E-mail: david.solomon@uconn.edu
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Abstract

We show, for each computable ordinal α and degree a > 0(α), the existence of a torsion-free abelian group with proper αth jump degree a.

Keywords

torsion-free abelian groupjump degree
Type
Research Article
Information
The Journal of Symbolic Logic , Volume 77 , Issue 4 , December 2012 , pp. 1067 - 1100
Copyright
Copyright © Association for Symbolic Logic 2012

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References

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