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arXiv · 1112.0437

Barycentric measure of quantum entanglement

Wojciech Ganczarek·Marek Kuś·Karol Życzkowski
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Abstract

Majorana representation of quantum states by a constellation of n 'stars' (points on the sphere) can be used to describe any pure state of a simple system of dimension n+1 or a permutation symmetric pure state of a composite system consisting of n qubits. We analyze the variance of the distribution of the stars, which can serve as a measure of the degree of non-coherence for simple systems, or an entanglement measure for composed systems. Dynamics of the Majorana points induced by a unitary dynamics of the pure state is investigated.

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Wojciech Ganczarek, Marek Kuś, Karol Życzkowski. 2011-12-18. Barycentric measure of quantum entanglement. https://doi.org/10.1103/physreva.85.032314

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