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Can quantum computer perform better than classical?

Robert Alicki
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Abstract

A theoretical model of a quantum device which can factorize any number N in two steps i.e. by preparing an input state and performing a measurement is discussed. The analysis reveals that the duration of state preparation and measurement is proportional to N while the energy consumption grows like log N. These results suggest the existence of Heisenberg-type relation putting limits on the efficiency of a quantum computer in terms of a total computation time, a total energy consumption and a classical complexity of the problem.

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Robert Alicki. 2000-06-05. Can quantum computer perform better than classical?. https://arxiv.org/abs/quant-ph/0006018

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