Chapter 17 - Teleportation

Portent

It would seem that nature keeps superluminal signalling all to herself. If we can’t use quantum entanglement for FTL, what can we use it for?

Primary Docs

Paradigm Discourse:
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Technical Chapter:
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Significance

Quantum teleportion is the slick utilization of quantum entanglement to copy a quantum state without the destructive use of a conventional measurement. Instead of measuring a single particle in either the orthogonal or angled bases, a joint measurement of two particles is performed in the Bell basis. One of those particles is the one to be cloned, the other is a member of an EPR pair where Bob is in possession of the other particle. Alice can therefor teleport the state of her particle to Bob, but it requires the use of a 2-bit classical communication channel to reveal to him the results of her measurement, so he can transform his particle into the state she wanted to teleport. The requirement for a classical channel precludes FTL but the requirement for a quantum channel implies that something superluminal happened.