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The undecidability of the Π4-theory for the r.e. wtt and Turing degrees

Published online by Cambridge University Press:  12 March 2014

Steffen Lempp  and
André Nies
Steffen Lempp
Affiliation:
Department of Mathematics, University of Wisconsin, Madison, Wisconsin 53706, E-mail: [email protected]
André Nies
Affiliation:
Department of Mathematics, University of Chicago, Chicago, Illinois 60637
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Abstract

We show that the Π4-theory of the partial order of recursively enumerable weak truth-table degrees is undecidable, and give a new proof of the similar fact for r.e. T-degrees. This is accomplished by introducing a new coding scheme which consists in defining the class of finite bipartite graphs with parameters.

Type
Research Article
Information
The Journal of Symbolic Logic , Volume 60 , Issue 4 , December 1995 , pp. 1118 - 1136
Copyright
Copyright © Association for Symbolic Logic 1995

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References

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