Quantum digital signature based on single-qubit without a trusted third-party
- 講者Masahito Hayashi 教授 (日本名古屋大學（Graduate School Mathematics, Nagoya University）與香港中文大學（The Chinese University of Hong Kong）合聘教授)
邀請人：鐘楷閔 - 時間2025-08-01 (Fri.) 10:30 ~ 12:00
- 地點資訊所新館101演講廳
摘要
Digital signatures are a powerful cryptographic tool widely employed across various industries for securely authenticating the identity of a signer during communication between signers and verifiers. While quantum digital signatures have been extensively studied, the security still depends on a trusted third-party. To address this limitation and enhance the applicability in real-world scenarios, here we propose a novel quantum digital signature protocol without a trusted third-party to further improve the security. We note that a quantum one-way function can work appropriately in digital signature due to the intrinsic non-cloning property for quantum states. Secret keys in the protocol are constituted by classical private keys and quantum public keys because we assume that no user is trusted in the protocol. We prove that the protocol has information-theoretical unforgeability. Moreover, it satisfies other important secure properties, including asymmetry, undeniability, and expandability. [arXiv:2410.13397]