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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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.
The authors declare no competing financial interests.
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). https://doi.org/10.1038/nature23458
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