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arXiv · 2301.02003

One-Way Ticket to Las Vegas and the Quantum Adversary

Aleksandrs Belovs·Duyal Yolcu
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Abstract

We propose a new definition of quantum Las Vegas query complexity. We show that it is exactly equal to the quantum adversary bound. This is achieved by a new and very simple way of transforming a feasible solution to the adversary optimisation problem into a quantum query algorithm. This allows us to generalise the bound to include unidirectional access, multiple input oracles, and input oracles that are not unitary. As an application, we demonstrate a separation between unidirectional and bidirectional access to an input oracle for a rather natural unitary permutation inversion problem.

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Aleksandrs Belovs, Duyal Yolcu. 2023-01-05. One-Way Ticket to Las Vegas and the Quantum Adversary. https://arxiv.org/abs/2301.02003

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