Editing Quantum Teleportation (section)

==Outline==

The quantum teleportation protocol begins with a quantum state or qubit, in the possession of the first party (the sender). We need this quantum state to be transferred to the second party (the receiver). This state is unknown to both parties meaning that the sender does not know the representation of the qubit on any basis. Before starting the protocol the two parties must share an entangled state (for example an [[EPR pair]]). The entangled state here is a two-qubit state where each party has one share of these qubits which have a special [[quantum correlation]]. After sharing the entangled state, the parties can take an arbitrary distance (In theory, without any noise and by assuming that the entanglement can be held for an arbitrary distance which is not the case in the real experiments). After this preparation stage, the two parties will perform the protocol as follows:</br>
* At sender's location, a Bell measurement of the EPR pair qubit and the qubit to be teleported is performed, yielding one of four measurement outcomes, which can be encoded in two classical bits of information. Both qubits at the sender's location are then discarded.
* Using the classical channel, the two bits are sent from the sender to the receiver.
* As a result of the measurement performed at the sender's location, the EPR pair qubit at the receiver's location is in one of four possible states. Of these four possible states, one is identical to the original quantum state, and the other three are closely related. Which of these four possibilities actually obtained, is encoded in the two classical bits. Knowing this, the EPR pair qubit at the receiver's location is modified by local unitary operations that the receiver performs on his state. And the result will be the original qubit.