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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
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: [email protected]

Abstract

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 $\mathcal{G}_{T,\omega}$.

Type
Paper
Copyright
© Cambridge University Press 2019 

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