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arXiv · 1912.06336

Additive-error fine-grained quantum supremacy

Tomoyuki Morimae·Suguru Tamaki
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Abstract

It is known that several sub-universal quantum computing models, such as the IQP model, the Boson sampling model, the one-clean qubit model, and the random circuit model, cannot be classically simulated in polynomial time under certain conjectures in classical complexity theory. Recently, these results have been improved to "fine-grained" versions where even exponential-time classical simulations are excluded assuming certain classical fine-grained complexity conjectures. All these fine-grained results are, however, about the hardness of strong simulations or multiplicative-error sampling. It was open whether any fine-grained quantum supremacy result can be shown for additive-error sampling. In this paper, we show the additive-error fine-grained quantum supremacy. As examples, we consider the IQP model, a mixture of the IQP model and log-depth Boolean circuits, and Clifford+$T$ circuits. Similar results should hold for other sub-universal models.

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Tomoyuki Morimae, Suguru Tamaki. 2019-12-13. Additive-error fine-grained quantum supremacy. https://doi.org/10.22331/q-2020-09-24-329

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