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arXiv · 1110.4540

Nonexistence of a universal quantum machine to examine the precision of unknown quantum states

Shengshi Pang·Shengjun Wu·Zeng-Bing Chen
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Abstract

In this work, we reveal a new type of impossibility discovered in our recent research which forbids comparing the closeness of multiple unknown quantum states with any non-trivial threshold in a perfect or an unambiguous way. This impossibility is distinct from the existing impossibilities in that it is a "collective" impossibility on multiple quantum states while most other "no-go" theorems concern with only one single state each time, i.e., it is an impossibility on a non-local quantum operation. This novel impossibility may provide a new insight into the nature of quantum mechanics and it implies more limitations on quantum information tasks than the existing "no-go" theorems.

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Shengshi Pang, Shengjun Wu, Zeng-Bing Chen. 2011-12-23. Nonexistence of a universal quantum machine to examine the precision of unknown quantum states. https://doi.org/10.1103/physreva.84.062313

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