The Ghost in the Quantum Turing Machine

  title={The Ghost in the Quantum Turing Machine},
  author={Scott Aaronson},
  booktitle={The Once and Future Turing},
  • S. Aaronson
  • Published in The Once and Future Turing 1 June 2013
  • Philosophy
In honor of Alan Turing's hundredth birthday, I unwisely set out some thoughts about one of Turing's obsessions throughout his life, the question of physics and free will. I focus relatively narrowly on a notion that I call "Knightian freedom": a certain kind of in-principle physical unpredictability that goes beyond probabilistic unpredictability. Other, more metaphysical aspects of free will I regard as possibly outside the scope of science. I examine a viewpoint, suggested independently by… 

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