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arXiv · 1812.03703

Impossibility of blind quantum sampling for classical client

Tomoyuki Morimae·Harumichi Nishimura·Yuki Takeuchi·Seiichiro Tani
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Abstract

Blind quantum computing enables a client, who can only generate or measure single-qubit states, to delegate quantum computing to a remote quantum server in such a way that the input, output, and program are hidden from the server. It is an open problem whether a completely classical client can delegate quantum computing blindly. In this paper, we show that if a completely classical client can blindly delegate sampling of subuniversal models, such as the DQC1 model and the IQP model, then the polynomial-time hierarchy collapses to the third level. Our delegation protocol is the one where the client first sends a polynomial-length bit string to the server and then the server returns a single bit to the client. Generalizing the no-go result to more general setups is an open problem.

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Tomoyuki Morimae, Harumichi Nishimura, Yuki Takeuchi, Seiichiro Tani. 2018-12-10. Impossibility of blind quantum sampling for classical client. https://arxiv.org/abs/1812.03703

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