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arXiv · 0912.3338

Superposition of macroscopically distinct states means large multipartite entanglement

Tomoyuki Morimae
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Abstract

We show relations between superposition of macroscopically distinct states and entanglement. These relations lead to the important conclusion that if a state contains superposition of macroscopically distinct states, the state also contains large multipartite entanglement in terms of several measures. Such multipartite entanglement property also suggests that if a state contains superposition of macroscopically distinct states, a measurement on a single particle drastically changes the state of macroscopically many other particles, as in the case of the N-qubit GHZ state.

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Tomoyuki Morimae. 2009-12-17. Superposition of macroscopically distinct states means large multipartite entanglement. https://doi.org/10.1103/physreva.81.010101

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