Degrees of Weakly Computable Reals

  • Keng Meng Ng
  • Frank Stephan
  • Guohua Wu
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3988)


This paper studies the degrees of weakly computable reals. It is shown that certain types of limit-recursive reals are Turing incomparable to all weakly computable reals except the recursive and complete ones. Furthermore, it is shown that an r.e. Turing degree is array-recursive iff every real in it is weakly computable.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Keng Meng Ng
    • 1
  • Frank Stephan
    • 2
  • Guohua Wu
    • 3
  1. 1.School of Mathematics, Statistics and Computer ScienceVictoria University of WellingtonNew Zealand
  2. 2.School of Computing and Department of MathematicsNational University of SingaporeSingapore
  3. 3.School of Physical and Mathematical SciencesNanyang Technological UniversitySingapore

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