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Wtt-degrees and T-degrees of r.e. sets

Published online by Cambridge University Press:  12 March 2014

Michael Stob
Michael Stob*
Affiliation:
Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
*
Calvin College, Grand Rapids, Michigan 49506
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Abstract

We use some simple facts about the wtt-degrees of r.e. sets together with a construction to answer some questions concerning the join and meet operators in the r.e. degrees. The construction is that of an r.e. Turing degree a with just one wtt-degree in a such that a is the join of a minimal pair of r.e. degrees. We hope to illustrate the usefulness of studying the stronger reducibility orderings of r.e. sets for providing information about Turing reducibility.

Type
Research Article
Information
The Journal of Symbolic Logic , Volume 48 , Issue 4 , December 1983 , pp. 921 - 930
Copyright
Copyright © Association for Symbolic Logic 1983

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References

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