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Definability in the local structure of the ω-Turing degrees

Published online by Cambridge University Press:  21 February 2019

Hristo Ganchev  and
Andrey C. Sariev
Hristo Ganchev
Affiliation:
Faculty of Mathematics and Informatics, Sofia University, Sofia, Bulgaria
Andrey C. Sariev*
Affiliation:
Faculty of Mathematics and Informatics, Sofia University, Sofia, Bulgaria
*
*Corresponding author. Email: andreys@fmi.uni-sofia.bg
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Abstract

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This article continues the study of the definability in the local substructure $\mathcal{G}_{T,\omega}$ of the ω-Turing degrees, initiated in (Sariev and Ganchev 2014). We show that the class I of the intermediate degrees is definable in $\mathcal{G}_{T,\omega}$.

Keywords

Turing reducibilityω-Turing degreesdegree structuresdefinabilityjump classes
Type
Paper
Information
Mathematical Structures in Computer Science , Volume 29 , Issue 7 , August 2019 , pp. 927 - 937
Copyright
© Cambridge University Press 2019 

References

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