古典Quantum randomized encodingの不可能性

• Item type: SIG Technical Reports(1)
• 公開日: 2021-03-22
• タイトル: 古典Quantum randomized encodingの不可能性
• タイトル / 言語: en
• タイトル: Impossibility of classical quantum randomized encoding
• 言語: eng
• 資源タイプ / 資源タイプ識別子: http://purl.org/coar/resource_type/c_18gh
• 資源タイプ: technical report
• 著者所属: 京都大学基礎物理学研究所
• 著者名: 森前, 智行
• 著者名(英): Tomoyuki, Morimae
• 論文抄録 / 内容記述タイプ: Other
• 論文抄録 / 内容記述: Randomized encoding is a powerful cryptographic primitive with various applications such as secure multiparty computation, verifiable computation, parallel cryptography, and complexity lower-bounds. Intuitively, randomized encoding f of a function f is another function such that f(x) can be recovered from f(x), and nothing except for f(x) is leaked from f(x). Its quantum version, quantum randomized encoding, has been introduced recently [Brakerski and Yuen, arXiv:2006.01085]. Intuitively, quantum randomized encoding F of a quantum operation F is another quantum operation such that, for any quantum state ρ, F(ρ) can be recovered from F(ρ), and nothing except for F(ρ) is leaked from F(ρ). In this paper, we show that if quantum randomized encoding of BB84 state generations is possible with an encoding operation E, then a two-round verification of quantum computing is possible with a classical verifier who can additionally do the operation E. One of the most important goals in the field of the verification of quantum computing is to construct a verification protocol with a verifier as classical as possible. This result therefore demonstrates a potential application of quantum randomized encoding to the verification of quantum computing: if we can find a good quantum randomized encoding (in terms of the encoding complexity), then we can construct a good verification protocol of quantum computing. We, however, also show that too good quantum randomized encoding is impossible: if quantum randomized encoding with a classical encoding operation is possible, then the no-cloning is violated. We finally consider a natural modification of blind quantum computing protocols in such a way that the server gets the output like quantum randomized encoding. We show that the modified protocol is not secure.
• 論文抄録(英) / 内容記述タイプ: Other
• 論文抄録(英) / 内容記述: Randomized encoding is a powerful cryptographic primitive with various applications such as secure multiparty computation, verifiable computation, parallel cryptography, and complexity lower-bounds. Intuitively, randomized encoding f of a function f is another function such that f(x) can be recovered from f(x), and nothing except for f(x) is leaked from f(x). Its quantum version, quantum randomized encoding, has been introduced recently [Brakerski and Yuen, arXiv:2006.01085]. Intuitively, quantum randomized encoding F of a quantum operation F is another quantum operation such that, for any quantum state ρ, F(ρ) can be recovered from F(ρ), and nothing except for F(ρ) is leaked from F(ρ). In this paper, we show that if quantum randomized encoding of BB84 state generations is possible with an encoding operation E, then a two-round verification of quantum computing is possible with a classical verifier who can additionally do the operation E. One of the most important goals in the field of the verification of quantum computing is to construct a verification protocol with a verifier as classical as possible. This result therefore demonstrates a potential application of quantum randomized encoding to the verification of quantum computing: if we can find a good quantum randomized encoding (in terms of the encoding complexity), then we can construct a good verification protocol of quantum computing. We, however, also show that too good quantum randomized encoding is impossible: if quantum randomized encoding with a classical encoding operation is possible, then the no-cloning is violated. We finally consider a natural modification of blind quantum computing protocols in such a way that the server gets the output like quantum randomized encoding. We show that the modified protocol is not secure.
• 書誌レコードID / 収録物識別子タイプ: NCID
• 書誌レコードID / 収録物識別子: AA12894105
• 書誌情報: 研究報告量子ソフトウェア（QS）; 巻 2021-QS-2, 号 16, p. 1-12, 発行日 2021-03-22
• ISSN / 収録物識別子タイプ: ISSN
• ISSN / 収録物識別子: 2435-6492
• Notice: SIG Technical Reports are nonrefereed and hence may later appear in any journals, conferences, symposia, etc.
• 出版者 / 言語: ja
• 出版者: 情報処理学会