The Low Splitting Theorem in the Difference Hierarchy

  • Angsheng Li
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3526)


It is shown that for any 2-computably enumerable Turing degrees a, l, if l ′ = 0′, and l < a, then there are 2-computably enumerable Turing degrees x 0, x 1 such that both lx 0, x 1 < a and x 0x 1 = a hold, extending the Robinson low splitting theorem for the computably enumerable degrees to the difference hierarchy.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • Angsheng Li
    • 1
  1. 1.Institute of SoftwareChinese Academy of SciencesBeijingP. R. China

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