Quantum Hoare Logic with Ghost Variables

Dominique Unruh

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arXiv · 1902.00325

Quantum Hoare Logic with Ghost Variables

Dominique Unruh

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Abstract

Quantum Hoare logic allows us to reason about quantum programs. We present an extension of quantum Hoare logic that introduces "ghost variables" to extend the expressive power of pre-/postconditions. Ghost variables are variables that do not actually occur in the program and are allowed to have arbitrary quantum states (in a sense, they are existentially quantified), and be entangled with program variables. Ghost variables allow us to express properties such as the distribution of a program variable or the fact that a variable has classical content. And as a case study, we show how quantum Hoare logic with ghost variables can be used to prove the security of the quantum one-time pad.

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BibTeX RIS

Dominique Unruh. 2019-02-01. Quantum Hoare Logic with Ghost Variables. https://arxiv.org/abs/1902.00325

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