Deutsch (“doytch”), Barenco, and Ekert showed that almost any 2-qubit (“two-Q-bit”) gate has this property and conjectured that the only gates to lack it are 1-qubit gates and classical gates. For 10 points each:
[10h] Name this property that is, perhaps surprisingly, generic in quantum computing. David Deutsch proved that quantum computers with this property can perfectly simulate any finitely realizable physical system.
ANSWER: universality [or quantum universality]
[10m] A universal set of quantum gates is obtained from using gates that perform this operation and a CNOT (“C-not”) gate. A Hadamard gate can be viewed as two of these operations on the standard geometrical representation of qubit state space.
ANSWER: qubit rotations [or rotations on/of the Bloch sphere; prompt on descriptions of any of the following actions happening to a qubit on the Bloch sphere: moving or transforming or transporting; reject “translations”]
[10e] These devices excite trapped ions in Cirac (“see-rahk”) and Zoller’s CNOT gate. The gain medium of these devices amplifies light via stimulated emission.
ANSWER: lasers [or light amplification by stimulated emission of radiation]
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