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Why can't Grover's algorithm apparently solve this simple situation?

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Mariia Mykhailova
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2 votes
1 answer
125 views

Questions on multi-controlled Toffolis and their implementation in Qiskit

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mavzolej
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2 answers
48 views

Does the $\text{CNOT}$ gate activate if the control qubit is $-|1⟩?$

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FDGod
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3 votes
1 answer
77 views

What is the difference between classical-quantum and completely classical states?

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Quantum Error Correction on a hexagonal lattice

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Craig Gidney
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If all terms of a local Hamiltonian commute, how hard is it to learn the ground state (energy)?

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Mark Spinelli
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Can you push a CZ gate through a Toffoli gate?

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Manuel
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53 views

How to determine the single-qubit phase?

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Curious
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A measure of entanglement created by a unitary operation

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Martin Vesely
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2 votes
2 answers
33 views

How to estimate the negative amplitude of multiple qubits?

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Martin Vesely
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1 vote
1 answer
33 views

Measuring one qubit in an entangled pair in another basis?

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DaftWullie
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2 answers
38 views

Access individual qubits of a quantum circuit in qiskit by qubit name

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Ash Ketchum
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0 answers
36 views

Parallelize estimation of expectation values in Qiskit

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ar3q5dr9
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34 views

general way to decompose a CZ gate on $n$-qubit system

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River
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1 answer
32 views

For arbitrary single-qubit unitary gate, does there exist a code such that the given gate is transversal?

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DaftWullie
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1 vote
1 answer
31 views

What is the difference between shot and iteration of the quantum circuit?

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Quantum Mechanic
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29 views

In Qiskit, no state vector after measure and reset

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Egretta.Thula
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27 views

Get confused about the implementation of Amplitude Amplifier

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Alexis
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ibmq belem noise model backend shows best result. why? [closed]

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Arpita
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25 views

Deriving a equation in "Data re-uploading for a universal quantum classifier" paper: U(phi1,phi2,phi3) U(x1,x2,x3) = U(theta + w *x)

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Aakash
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1 vote
1 answer
25 views

Post selection during hook injection

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Craig Gidney
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1 vote
1 answer
19 views

Is qiskit.pulse.SamplePulse deprecated?

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Martin Vesely
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0 answers
24 views

Error on expectation value even with zero noise

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stopper
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24 views

is the main purpose of using Schmidt decompositon to visualize entanglement?

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Hadamard
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How to 'quantize' a classical code?

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Ash Ketchum
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0 answers
23 views

Remove a register from a quantum circuit

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Ash Ketchum
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4 votes
0 answers
23 views

How do I calculate the expectation of the rational function, in the sense of the Haar measure?

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Dan David
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0 answers
23 views

The Quantum Mobility Quest - Airbus & BMW Group [closed]

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geforfn
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20 views

How to actually solve for the eigenstates in the adiabatic version of Grover's algorithm

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requiemman
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1 answer
20 views

References for mapping qudit gates to qubits equivalent

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Mark Spinelli
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19 views

How can I initialize a classic register in qiskit?

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Qubii
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19 views

Implementing a Quantum Recurrent Neural Network

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MoBlufiz
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1 answer
17 views

Passing a book-keeping parameter to Qiskit Ibm Runtime Estimator

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Egretta.Thula
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0 answers
16 views

Specifying the image of a set of states under the action of a channel

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forky40
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15 views

How to deal with unused qubits in application specific quantum chips?

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Shadow43375
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Can I get valid solution with HHL algorithm even if the QPE is not completely correct?

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Nyyni
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0 answers
14 views

Product for block-encoding of two density operators

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Dan David
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11 views

Accuracy of QPE using histogram fit

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Ron Cohen
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