Minds and Machines

, Volume 13, Issue 1, pp 87–101 | Cite as

Physical Hypercomputation and the Church–Turing Thesis

  • Oron Shagrir
  • Itamar Pitowsky


We describe a possible physical device that computes a function that cannot be computed by a Turing machine. The device is physical in the sense that it is compatible with General Relativity. We discuss some objections, focusing on those which deny that the device is either a computer or computes a function that is not Turing computable. Finally, we argue that the existence of the device does not refute the Church–Turing thesis, but nevertheless may be a counterexample to Gandy's thesis.

Church–Turing thesis effective computation Gandy's thesis physical hypercomputation supertasks 


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Copyright information

© Kluwer Academic Publishers 2003

Authors and Affiliations

  • Oron Shagrir
    • 1
  • Itamar Pitowsky
    • 1
  1. 1.Department of PhilosophyThe Hebrew University of JerusalemIsrael

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