Quantum mechanics near closed timelike lines.

  title={Quantum mechanics near closed timelike lines.},
  journal={Physical review. D, Particles and fields},
  volume={44 10},
  • Deutsch
  • Published 15 November 1991
  • Physics, Medicine
  • Physical review. D, Particles and fields
The methods of the quantum theory of computation are used to analyze the physics of closed timelike lines. This is dominated, even at the macroscopic level, by quantum mechanics. In classical physics the existence of such lines in a spacetime imposes "paradoxical" constraints on the state of matter in their past and also provides means for knowledge to be created in ways that conflict with the principles of the philosophy of science. In quantum mechanics the first of these pathologies does not… 

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