- #1
Peter_Newman
- 155
- 11
Hello,
I have a question about the measurement of a qubit in the computational basis. I would like to first state what I know so far and then ask my actual question at the end.What I know:
Let's say we have a qubit in the general state of . Now we can define the following measurement operators depending on whether we want to measure the qubit in state or . Let's say I am interested in the state .
The corresponding operator would then be defined as follows . The probability of obtaining a measurement outcome is then defined by:
.My Question:
I read the following in the Wikipedia article on Quantum Phase Estimation (Wiki, section measurement). We have now given there the following quantum state:
Now it is said that a measurement in the computational basis on the first register yields the result with probability;
I am interested in the last equation here ( ), how do you arrive at it? With what I know so far, I can't really derive the last equation, so I would be interested in knowing how the derivation is. Also the simplification does not open up to me. Maybe someone here can demystify it.
I have a question about the measurement of a qubit in the computational basis. I would like to first state what I know so far and then ask my actual question at the end.What I know:
Let's say we have a qubit in the general state of
The corresponding operator would then be defined as follows
I read the following in the Wikipedia article on Quantum Phase Estimation (Wiki, section measurement). We have now given there the following quantum state:
Now it is said that a measurement in the computational basis on the first register yields the result
I am interested in the last equation here (
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