Fidelity of quantum strategies with applications to cryptography

We introduce a definition of the fidelity function for multi-round quantum strategies, which we call the strategy fidelity, that is a generalization of the fidelity function for quantum states. We provide many interesting properties of the strategy fidelity including a Fuchs-van de Graaf relationshi...

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Detalles Bibliográficos
Autores principales: Sikora, Jamie, Gutoski, Gus, Rosmanis, Ansis
Otros Autores: School of Physical and Mathematical Sciences
Formato: Journal Article
Lenguaje:English
Publicado: 2018
Materias:
Acceso en línea:https://hdl.handle.net/10356/89408
http://hdl.handle.net/10220/46211
Descripción
Sumario:We introduce a definition of the fidelity function for multi-round quantum strategies, which we call the strategy fidelity, that is a generalization of the fidelity function for quantum states. We provide many interesting properties of the strategy fidelity including a Fuchs-van de Graaf relationship with the strategy norm. We illustrate an operational interpretation of the strategy fidelity in the spirit of Uhlmann's Theorem and discuss its application to the security analysis of quantum protocols for interactive cryptographic tasks such as bit-commitment and oblivious string transfer. Our analysis is very general in the sense that the actions of the protocol need not be fully specified, which is in stark contrast to most other security proofs. Lastly, we provide a semidefinite programming formulation of the strategy fidelity.