4
votes
Accepted
What is qubit decoherence?
When we measure a qubit in superposition, we interact with the system, causing it to collapse into either $|0\rangle$ or $|1\rangle$, with certain probabilities determined by the coefficients in the ...
3
votes
Is it possible to produce an entangled state by measuring an unentangled state?
Depends on what you mean by "measuring". A "measure", in and of itself, produces (classical) outcomes, not necessarily states. But you can consider the quantum states that "...

glS♦
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2
votes
Accepted
Half Adder using CNOT Gates
Half adder circuit provides two outputs, sum and carry. The circuit in your question computes the sum, while the text talks about the carry!
This statement:
If you look again at the four possible ...
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