13.9: Quantum Communication
- Page ID
- 52464
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Two of the most tantalizing applications of quantum mechanics applied to information theory come from the field of communications. The first is the possibility that a quantum computer could break classical cryptographic codes in virtually no time. The second is the idea that quantum bits can be teleported.
In this section we will review the principles behind both teleportation and quantum cryptography (the solution to the problem of code breaking). As we are about to see, entanglement is key in both applications. The two most famous characters in communications: Alice and Bob, will play the main role in teleportation. For quantum cryptography, Eve will play a supporting role.