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ROM-based computation: quantum versus classical

B. C. Travaglione·M. A. Nielsen·H. M. Wiseman·A. Ambainis
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Abstract

We introduce a model of computation based on read only memory (ROM), which allows us to compare the space-efficiency of reversible, error-free classical computation with reversible, error-free quantum computation. We show that a ROM-based quantum computer with one writable qubit is universal, whilst two writable bits are required for a universal classical ROM-based computer. We also comment on the time-efficiency advantages of quantum computation within this model.

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B. C. Travaglione, M. A. Nielsen, H. M. Wiseman, A. Ambainis. 2002-07-02. ROM-based computation: quantum versus classical. https://arxiv.org/abs/quant-ph/0109016

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