Questions tagged [deferred-measurement]
The "principle of deferred measurement" refers to the idea that in almost all cases measurement may be performed as a last step in a quantum computation. This tag is dedicated to questions that explore the concept and/or potential exceptions to the concept.
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what does it mean to "measure a qubit" if measurement is defined on operators
As far as I know "measurement" depends on the two variables : state and operator.
So what exactly does measuring a qubit mean? is it implied that the operator is
the $Z$ operator on that ...
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Show that the effect of a Controlled Unitary on qubits followed by a measurement is unchanged depending on when measurement is taken
I understand that a Controlled Unitary is just a generalization of a control gate, such as CNOT etc, and that it is given in state representation as $$\hat C_U = |0\rangle\langle0|\otimes\mathbb{I} + |...
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What is a proof for the principle of deferred measurement?
Does anyone know of a proof for the 'principle of deferred measurement'?
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Using principle of deferred measurement to replace gates conditional on classical bits (c_if)
I am trying to implement the Iterative Phase Estimation algorithm on one of Qiskit's labs. I can do it for a 'nice' phase, such as 1/4 :
But if I want to implement the algo generally (as a subroutine ...
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Are there any algorithms that take measurements in an intermediate step?
As a beginner in quantum computation, I noticed that all quantum algorithms take various gates followed by measuring the qubits in the last step. Is it always the case? Are there any algorithms that ...
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Does principle of deferred measurement imply information can travel faster than light?
I have been reading the book by Michael A Nielsen and Isaac Chuang and came across the principle of deferred measurement. They showed using this principle how the circuit for quantum teleportation can ...