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Comment on ``Testing integrability with a single bit of quantum information''

Howard M. Wiseman
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Abstract

In quant-ph/0303042, Poulin, Laflamme, Milburn and Paz consider the problem of distinguishing quantum chaos from quantum integrability for dynamics in an $N$-dimensional Hilbert space. They claim that this can be done by deterministic quantum computing with a single bit using $O(\sqrt{N})$ physical resources, compared to O(N) physical resources classically. I point out what seems to be a fatal flaw with their proposal.

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Howard M. Wiseman. 2003-05-25. Comment on ``Testing integrability with a single bit of quantum information''. https://arxiv.org/abs/quant-ph/0305153

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