Realizability Models Separating Various Fan Theorems

  • Robert S. Lubarsky
  • Michael Rathjen
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7921)


We develop a realizability model in which the realizers are the reals not just Turing computable in a fixed real but rather the reals in a countable ideal of Turing degrees. This is then applied to prove several separation results involving variants of the Fan Theorem.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  • Robert S. Lubarsky
    • 1
  • Michael Rathjen
    • 2
  1. 1.Department of Mathematical SciencesFlorida Atlantic UniversityBoca RatonU.S.A.
  2. 2.Department of Pure MathematicsUniversity of LeedsLeedsEngland

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