# Quantum theory, the Church–Turing principle and the universal quantum computer

@article{Deutsch1985QuantumTT, title={Quantum theory, the Church–Turing principle and the universal quantum computer}, author={D. Deutsch}, journal={Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences}, year={1985}, volume={400}, pages={117 - 97} }

It is argued that underlying the Church–Turing hypothesis there is an implicit physical assertion. Here, this assertion is presented explicitly as a physical principle: ‘every finitely realizible physical system can be perfectly simulated by a universal model computing machine operating by finite means’. Classical physics and the universal Turing machine, because the former is continuous and the latter discrete, do not obey the principle, at least in the strong form above. A class of model… Expand

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