Category: Publication

Posted on

A Random Sequence of Reals

Since this paper was rejected by a Journal, I will divide the results, extend them and publish by some papers.

News
Jan 11, 2011, Rejected
Aug 2, 2010, Submitted to a Journal

Title
A Random Sequence of Reals

Type
Fullpaper

Journal
Unpublished

Download
preprint
Japanese summary

Abstract
We define a random sequence of reals as a random point on a computable topological space. This randomness has three equivalent simple characterizations, namely, by tests, by martingales and by complexity. We prove that members of a random sequence are relatively random. Conversely a relatively random sequence of reals has a random sequence such that each corresponding member is Turing equivalent. Furthermore strong law of large numbers and the law of the iterated logarithm hold for each random sequence.

Posted on

An extension of van Lambalgen’s Theorem to infinitely many relative 1-random reals

Title
An extension of van Lambalgen’s Theorem to infinitely many relative 1-random reals

Type
Fullpaper

Journal
Notre Dame Journal of Formal Logic, 51(3):337-349, 2010.
Permanent link to this document in this Journal.
Received November 30, 2009; accepted December 8, 2009; printed June 16, 2010

Download
preprint
Japanese summary

Abstract
Van Lambalgen’s Theorem plays an important role in algorithmic randomness, especially when studying relative randomness. In this paper we extend van Lambalgen’s Theorem by considerint the join of infinitely many reals which are random relative to each other.
In addition, we study computability of the reals in the range of Omega operators. It is known that $\Omega^{\phi’}$ is high. We extend this result to that $\Omega^{\phi^{(n)}}$ is $\textrm{high}_n$. We also prove that there exists A such that, for each n, the real $\Omega^A_M$ is highn for some universal Turing machine M by using the extended van Lambalgen’s Theorem.

Cited by
@article{bienvenu2010ergodic,
title={{Ergodic-type characterizations of algorithmic randomness}},
author={Bienvenu, L. and Day, A. and Mezhirov, I. and Shen, A.},
journal={Programs, Proofs, Processes},
pages={49–58},
year={2010},
publisher={Springer}
}
@article{bienvenu2011constructive,
title={A constructive version of Birkhoffʼs ergodic theorem for Martin–L{\”o}f random points},
author={Bienvenu, L. and Day, A. and Hoyrup, M. and Mezhirov, I. and Shen, A.},
journal={Information and Computation},
year={2011},
publisher={Elsevier}
}
@article{yu2011characterizing,
title={Characterizing strong randomness via Martin-L{\”o}f randomness},
author={Yu, L.},
journal={Annals of Pure and Applied Logic},
year={2011},
publisher={Elsevier}
}