Annali di Matematica Pura ed Applicata

, Volume 174, Issue 1, pp 97–120 | Cite as

Quasi-minimal enumeration degrees and minimal Turing degrees

  • Theodore A. Slaman
  • A. Sorbi
Article

Abstract

We show that there exists a set A such that A has quasi-minimal enumeration degree, and there are uncountably many sets B such that A is enumeration reducible to B and B has minimal Turing degree. Answering a related question raised by Solon, we also show that there exists a nontotal enumeration degree which is not e-hyperimmune.

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Copyright information

© Fondazione Annali di Matimatica Pura ed Applicata 1998

Authors and Affiliations

  • Theodore A. Slaman
    • 1
  • A. Sorbi
    • 2
  1. 1.Department of MathematicsUniversity of ChicagoChicagoUSA
  2. 2.Department of MathematicsUniversity of SienaSienaItaly

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