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arXiv · 1204.1212

Kind of entanglement that speeds up quantum evolution

Florian Fröwis
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Abstract

The "speed" of unitary quantum evolution was recently shown to be connected to entanglement in multipartite quantum systems. Here, we discuss a tighter version of the Mandelstam-Tamm uncertainty relation that depends on the Fisher information. The passage time is estimated by a lower bound that depends inversely proportional to the square root of the Fisher information. This leads to a better understanding of the origin of a fast quantum time evolution of entangled states.

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Florian Fröwis. 2012-05-31. Kind of entanglement that speeds up quantum evolution. https://doi.org/10.1103/physreva.85.052127

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