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Lowness and nullsets

Published online by Cambridge University Press:  12 March 2014

Rod Downey ,
Andre Nies ,
Rebecca Weber  and
Liang Yu
Rod Downey
Affiliation:
Victoria University, School of Mathematics, Statistics and Computer Science, P.O. Box 600, Wellington, New Zealand.E-mail:Rod.Downey@vuw.ac.nz
Andre Nies
Affiliation:
The University of Auckland, Department of Computer Science, Private Bag 92019, Auckland, New Zealand.E-mail:nies@cs.auckland.ac.nz
Rebecca Weber
Affiliation:
Dartmouth College, Department of Mathematics, 6188 Bradley Hall, Hanover, NH 03755, USA.E-mail:rweber@math.dartmouth.edu
Liang Yu
Affiliation:
National University of Singapore, Department of Mathematics, Lower Kent Ridge Road, Singapore 117543, Singapore.E-mail:yuliang.nju@gmail.com
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Abstract

We prove that there exists a noncomputable c.e. real which is low for weak 2-randomness, a definition of randomness due to Kurtz, and that all reals which are low for weak 2-randomness are low for Martin-Löf randomness.

Type
Research Article
Information
The Journal of Symbolic Logic , Volume 71 , Issue 3 , September 2006 , pp. 1044 - 1052
Copyright
Copyright © Association for Symbolic Logic 2006

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References

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