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arXiv · 2403.14416

Quantum Channel Simulation in Fidelity is no more difficult than State Splitting

Michael X. Cao·Rahul Jain·Marco Tomamichel
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Abstract

Characterizing the minimal communication needed for the quantum channel simulation is a fundamental task in the quantum information theory. In this paper, we show that, in fidelity, the quantum channel simulation can be directly achieved via quantum state splitting without using a technique known as the de~Finetti reduction, and thus provide a pair of tighter one-shot bounds. Using the bounds, we also recover the quantum reverse Shannon theorem in a much simpler way.

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Michael X. Cao, Rahul Jain, Marco Tomamichel. 2024-03-21. Quantum Channel Simulation in Fidelity is no more difficult than State Splitting. https://arxiv.org/abs/2403.14416

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