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Entanglement vs. Noncommutativity in Teleportation

Sibasish Ghosh·Guruprasad Kar·Anirban Roy·Ujjwal Sen
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Abstract

We provide an alternative simple proof of the necessity of entanglement in quantum teleportation by using the no-disentanglement theorem. We show that this is true even when the state to be teleported is known to be among two noncommuting qubits. We further show that to teleport any set of commuting qubits, it is sufficient to have a classically correlated channel. Using this result we provide a simple proof of the fact that any set of bipartite entangled states can be exactly disentangled if the single particle density matrices of any one party commute.

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Sibasish Ghosh, Guruprasad Kar, Anirban Roy, Ujjwal Sen. 2001-07-18. Entanglement vs. Noncommutativity in Teleportation. https://arxiv.org/abs/quant-ph/0010012

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