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I am introduced to ancilla qubits which are usually initialized to $\vert 0 \rangle$. It seems that an ancilla qubit is equivalent to the $0$ bit in classical computing as it will evaluate to $\vert 0 \rangle$ 100% of the time. My question is that can I conclude **any** qubit will **always** be in superposition regardless of the probabilities of $\alpha$ and $\beta$ since $\vert 0 \rangle + 0\vert 1 \rangle = \vert 0 \rangle$ and $0\vert 0 \rangle + \vert 1 \rangle = \vert 1 \rangle$? How about physically, are qubits prepared according to some procedure that differ if it will be initialized to $\vert 0 \rangle$ or $\vert 1 \rangle$ or in superposition?

**Edit:** this is a related comment but it doesn't answer my question regarding if the process of physically preparing qubits different from non-entangled qubits vs entangled ones.

Does this answer your question? Represent qubit in a superposition

– Martin Vesely – 2019-12-27T10:31:14.767Regarding your statement "It seems that an ancilla qubit is equivalent to the $0$ bit in classical computing as it will evaluate to $\vert 0\rangle$ 100$ of the time," you mean "it will

initiallyevaluate to $\vert 0\rangle$...", right? – Mark S – 2019-12-27T13:38:24.153Yes, initial value. – M. Al Jumaily – 2019-12-27T13:41:23.083

@Martin Vesely, thanks for the suggestion. I read the answers there but unfortunately, I still have doubts. – M. Al Jumaily – 2019-12-27T13:50:48.450