Quantum Cryptography - Text by Anders Sandberg in his Transhuman Terminology A system based on quantum-mechanical principles. Eavesdroppers alter the quantum state of the system and so are detected.
Quantum Decoherence - Text by M. Alan Kazlev A process in which the ambiguous quantum state of a particle, such as the nuclear spin of an electron representing a qubit in a quantum computer, is resolved into an unambiguous state, whether measured or not (conscious observers are not needed).
Quantum Entanglement Device, QED - Text by M. Alan Kazlev with note by Anders Sandberg Mythological godtech or clarketech communications device that supposedly employs quantum entanglement for limited "ftl" communicate at interstellar distances. Said to be in the hands of powers and archailects. It is commonly believed or supposed in cheap virchfiction that a few have over the centuries fallen into the hands of nearbaselines, who have however been able to use them to their useful potential. The reality is that no QED has ever existed; as with FTL it is a myth that is believed by the gullible. It has been known ever since the Atomic and Information ages of Old Earth that actual quantum entanglement cannot be used to send useful information.