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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: [email protected]
Theodore A. Slaman
Affiliation:
University of California, Berkeley, Department of Mathematics, Berkeley, Ca 94720-3840, USA, E-mail: [email protected]

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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References

REFERENCES

[1]Ambos-Spies, K. and Kučera, A., Randomness in computability theory, Computability Theory and its Applications (Boulder, CO, 1999), Contemporary Mathematics, vol. 257, American Mathematical Society, Providence, RI, 2000, pp. 114.CrossRefGoogle Scholar
[2]Chaitin, G. J., Algorithmic information theory, IBM Journal of Research and Development, vol. 21 (1977), no. 4, pp. 350359.CrossRefGoogle Scholar
[3]Downey, R. and Hirschfeldt, D. R., Algorithmic Randomness and Complexity, Springer, to appear.Google Scholar
[4]Downey, R., Hirschfeldt, D. R., Nies, A., and Stephan, F., Trivial reals, Proceedings of the 7th and 8th Asian Logic Conferences, Singapore University Press, 2003, pp. 103131.CrossRefGoogle Scholar
[5]Downey, R., Hirschfeldt, D. R., Nies, A., and Terwijn, S. A., Calibrating randomness, The Bulletin of Symbolic Logic, vol. 12 (2006), no. 3, pp. 411491.CrossRefGoogle Scholar
[6]Hirschfeldt, D. R., Nies, A., and Stephan, F., Using random sets as oracles. Journal of the London Mathematical Society, vol. 75 (2007), no. 3, pp. 610622.CrossRefGoogle Scholar
[7]Jockusch, C. G. Jr and Soare, R. I., Π10 classes and degrees of theories, Transactions of the American Mathematical Society, vol. 173 (1972), pp. 3356.Google Scholar
[8]Kučera, A., On the use of diagonally nonrecursive functions, Logic Colloquium '87 (Granada, 1987) (Ebbinghaus, H.-D.et al., editors), Studies in Logic and the Foundations of Mathematics, vol. 129, North-Holland, Amsterdam, 1989, pp. 219239.CrossRefGoogle Scholar
[9]Kučera, A., On relative randomness, Annals of Pure and Applied Logic, vol. 63 (1993), no. 1, pp. 6167, 9th International Congress of Logic, Methodology and Philosophy of Science (Uppsala, 1991).Google Scholar
[10]Kučera, A. and Terwijn, S. A., Lownessfor the class of random sets, this Journal, vol. 64 (1999), no. 4, pp. 13961402.Google Scholar
[11]Li, M. and Vitányi, P., An Introduction to Kolmogorov Complexity audits Applications, 2nd ed., Graduate Texts in Computer Science, Springer-Verlag, New York. 1997.CrossRefGoogle Scholar
[12]Miller, J. S. and Nies, A., Randomness and computability: Open questions, The Bulletin of Symbolic Logic, vol. 12 (2006), no. 3, pp. 390410.CrossRefGoogle Scholar
[13]Nerode, A. and Shore, R. A., Reducibility orderings: Theories, definability and automorphisms. Annals of Mathematical Logic, vol. 18 (1980), pp. 6189.CrossRefGoogle Scholar
[14]Nies, A., Lowness properties and randomness, Advances in Mathematics, vol. 197 (2005), no. 1, pp. 274305.CrossRefGoogle Scholar
[15]Nies, A., Reals which compute little, Proceedings of Logic Colloquium '02 (Chatzidakis, Zoé. Koepke, Peter, and Pohlers, Wolfram, editors), Lecture Notes in Logic, vol. 27, Association for Symbolic Logic, La Jolla, CA, 2006, pp. 261275.Google Scholar
[16]Nies, A., Computability and Randomness, Oxford University Press, 2009.CrossRefGoogle Scholar
[17]Odifreddi, P., Classical Recursion Theory, vol. I: The Theory of Functions and Sets of Natural Numbers, Studies in Logic and the Foundations of Mathematics, vol. 125, North-Holland Publishing Co., Amsterdam, 1989.Google Scholar
[18]Odifreddi, P., Classical Recursion Theory, vol. II, Studies in Logic and the Foundations of Mathematics, vol. 143, North-Holland Publishing Co., Amsterdam, 1999.Google Scholar
[19]Robinson, R. W., Interpolation and embedding in the recursively enumerable degrees, Annals of Mathematics, vol. 93 (1971), pp. 285314.CrossRefGoogle Scholar
[20]Scott, D., Algebras of sets binumerable in complete extensions of arithmetic. Recursive Function Theory, Proceedings of Symposia in Pure Mathematics, vol. 5, American Mathematical Society, 1962, pp. 117121.CrossRefGoogle Scholar
[21]Simpson, S., Degrees of unsolvability: A survey of results. Handbook of Mathematical Logic (Barwise, J., editor), North-Holland, Amsterdam, 1977, pp. 631652.CrossRefGoogle Scholar
[22]Soare, R. I., Recursively Enumerable Sets and Degrees, Perspectives in Mathematical Logic, Omega Series, Springer-Verlag, Heidelberg, 1987.CrossRefGoogle Scholar
[23]Yates, C. E. M., On the degrees of index sets. II, Transactions of the American Mathematical Society, vol. 135 (1969), pp. 249266.CrossRefGoogle Scholar