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Quantum computational supremacy


The field of quantum algorithms aims to find ways to speed up the solution of computational problems by using a quantum computer. A key milestone in this field will be when a universal quantum computer performs a computational task that is beyond the capability of any classical computer, an event known as quantum supremacy. This would be easier to achieve experimentally than full-scale quantum computing, but involves new theoretical challenges. Here we present the leading proposals to achieve quantum supremacy, and discuss how we can reliably compare the power of a classical computer to the power of a quantum computer.

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Figure 1: A 2D lattice of superconducting qubits proposed as a way to demonstrate quantum supremacy.

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A.W.H. was funded by NSF grants CCF-1629809 and CCF-1452616. A.M. was supported by EPSRC Early Career Fellowship EP/L021005/1. No new data were created during this study.

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A.W.H. and A.M. contributed equally to all aspects of this Insight Review.

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Correspondence to Ashley Montanaro.

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The authors declare no competing financial interests.

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Reviewer Information Nature thanks B. Fefferman, S. Jordan, J. Preskill and the other anonymous reviewer(s) for their contribution to the peer review of this work.

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Harrow, A., Montanaro, A. Quantum computational supremacy. Nature 549, 203–209 (2017).

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