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Low upper bounds of ideals

Published online by Cambridge University Press:  12 March 2014

Antonín Kučera
Affiliation:
Charles University, Faculty of Mathematics and Physics, Department of Theoretical Computer Science, and Mathematical Logic, Malostranské Nám. 25, 118 00 Praha 1., Czech Republic, E-mail: kucera@ksi.mff.cuni.cz
Theodore A. Slaman
Affiliation:
University of California, Berkeley, Department of Mathematics, Berkeley, Ca 94720-3840, USA, E-mail: slaman@math.berkeley.edu

Abstract

We show that there is a low T-upper bound for the class of K-trivial sets, namely those which are weak from the point of view of algorithmic randomness. This result is a special case of a more general characterization of ideals in T-degrees for which there is a low T-upper bound.

Type
Research Article
Copyright
Copyright © Association for Symbolic Logic 2009

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