Counterfactual computation

  title={Counterfactual computation},
  author={Graeme J. Mitchison and Richard Jozsa},
  journal={Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences},
  pages={1175 - 1193}
  • G. Mitchison, R. Jozsa
  • Published 2 July 1999
  • Computer Science, Mathematics
  • Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences
Suppose that we are given a quantum computer programmed ready to perform a computation if it is switched on. Counterfactual computation is a process by which the result of the computation may be learnt without actually running the computer. Such processes are possible within quantum physics and to achieve this effect a computer embodying the possibility of running the computation must be available, even though the computation is, in fact, not run. We study the possibilities and limitations of… 

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