Quantum teleportation
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http://en.wikipedia.org/wiki/Quantum_teleportation:
''Quantum teleportation, or entanglement-assisted teleportation, is a
technique used to transfer quantum information from one quantum system
to another. It does not transport the system itself''
''quantum teleportation'' sounds much more impressive than ''copying
the state of a photon''. But it is not even the latter. For copying
in the traditional sense does not destroy the original, whereas
teleportation does.
Copying a state exactly is forbidden by the so-called no-cloning
theorem. Teleportation, on the other hand, consists of destroying the
state at one location and reconstructing it exactly at another location.
So information is transported, but the state is destroyed and recreated,
hence copied. Not cloned. There is only at most one copy around each
time. This is not forbidden by the no-cloning theorem.