Non-deterministic Halting Times for Hamkins-Kidder Turing Machines

  • P. D. Welch
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3988)


In this talk we consider some issues related to the Infinite Time Turing Machine (ITTM) model of Hamkins & Lewis [3]. In particular our main results (Propositions 1 & 2) relate to Bounding times of the lengths of certain computations, and their application to certain questions raised in [2] on “non-determinism” both in terms of non-deterministically halting ordinals (Theorem 2) and pointclasses defined by using such non-deterministic machines (Proposition 6).


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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • P. D. Welch
    • 1
  1. 1.School of MathematicsUniversity of BristolEngland

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