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Decomposition and infima in the computably enumerable degrees

Published online by Cambridge University Press:  12 March 2014

Rodney G. Downey ,
Geoffrey L. Laforte  and
Richard A. Shore
Rodney G. Downey
Affiliation:
School of Mathematical and Computing Sciences, Victoria University, P.O. BOX 600, Wellington, New Zealand, E-mail: [email protected]
Geoffrey L. Laforte
Affiliation:
Department of Computer Science, University of West Florida, 11000 University Parkway, Pensacola, FL 32514, USA, E-mail: [email protected]
Richard A. Shore
Affiliation:
Department of Mathematics, Malott Hall, Cornell University, Ithaca, NY 14853, USA, E-mail: [email protected]
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Abstract

Given two incomparable c.e. Turing degrees a and b, we show that there exists a c.e. degree c such that c = (a ∪ c) ∩ (b ∪ c), a ∪ c ∣ b ∪ c, and c < a ∪ b.

Type
Research Article
Information
The Journal of Symbolic Logic , Volume 68 , Issue 2 , June 2003 , pp. 551 - 579
Copyright
Copyright © Association for Symbolic Logic 2003

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References

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