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Top Questions

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1 answer
11 views

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

0 votes
0 answers
11 views

How to 'quantize' a classical code?

1 vote
1 answer
630 views

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

1 vote
1 answer
20 views

Measuring one qubit in an entangled pair in another basis?

1 vote
1 answer
18 views

Is qiskit.pulse.SamplePulse deprecated?

1 vote
0 answers
16 views

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

3 votes
1 answer
69 views

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

3 votes
0 answers
35 views

A measure of entanglement created by a unitary operation

2 votes
1 answer
46 views

What does "lift" mean in the Lifted Product (LP) Code?

2 votes
1 answer
66 views

Finding the "dual" basis of an overcomplete basis for Quantum State Tomography

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0 answers
13 views

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

1 vote
0 answers
11 views

Accuracy of QPE using histogram fit

1 vote
0 answers
23 views

Get confused about the implementation of Amplitude Amplifier

2 votes
1 answer
50 views

Why can't we do pure state tomography using interference with a known reference state?

2 votes
1 answer
44 views

Number of logical cycles to implement $R_Z(\theta)$ gates in lattice surgery: why isn't it the number of layers $\times$ the $T$-count in $R_Z$?

0 votes
1 answer
42 views

Custom gate labels in PennyLane

1 vote
2 answers
63 views

Why $\sqrt{\rho} = P \sqrt{\rho}$ in the proof of quantum error correction conditions in Nielsen & Chuang?

1 vote
1 answer
76 views

Problem with the mathematical definition of the eigenvalue algorithm on a specific exercise

4 votes
1 answer
119 views

Bug in stim HERALDED_PAULI_CHANNEL_1?

0 votes
0 answers
15 views

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

2 votes
1 answer
62 views

How do I write a stim diagram to a file?

1 vote
0 answers
37 views

Generalization of representing SU(2) as quaternions

2 votes
0 answers
93 views

Mutual information of shared state is larger than expectation values

2 votes
1 answer
149 views

Problem with eigenvalue evaluation algorithm application on matrix $U$

5 votes
2 answers
82 views

Decomposition of a $4 \times 4$ unitary matrix

1 vote
2 answers
84 views

Is there a way to perform Zero Noise Extrapolation with qiskit without using the runtime service?

0 votes
1 answer
39 views

Matrices size of n-qubit controlled gates and n+2 states qubit?

2 votes
1 answer
51 views

Quantum homomorphic encryption with a classical verifier - clarifying the setting?

3 votes
1 answer
98 views

How much complexity is required to implement $\text{C$_\Pi$NOT}$ gate?

2 votes
2 answers
61 views

What is the relation between number of measurements and additive error, when estimating the expectation value of an observable?

0 votes
1 answer
33 views

Litinsky's fast block scheme: should the tile count also include the number of **purified** magic-states

4 votes
2 answers
323 views

How to convert a partially entangled state into maximally entangled using SLOCC

2 votes
1 answer
60 views

Underlying Hamiltonians and pulse level controls of different commercially available quantum computers

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70 views
+50

How comes the constraint $\sum_{n, m \neq 1} \chi_{n m} \Upsilon_m^{\dagger} \Upsilon_n=0$?

1 vote
1 answer
38 views

Q#: how to write an algorithm in modular form (I don't understand the syntax and the documentation is a bit obscure)

2 votes
0 answers
59 views

Are there quantum algorithms to estimate the partial transpose?

1 vote
0 answers
31 views

Effect of error correction gates in QCNN

1 vote
1 answer
21 views

Applying Hadamard on inexistent qubit doesn't make Q# compilation fail: why?

0 votes
1 answer
20 views

How to get line fits from sinter.plot_error_rate to calculate logical error rate as function of physical

1 vote
1 answer
25 views

Understanding command Ignore in Q#

2 votes
0 answers
24 views

Role of eavesdroppers in B92 of phase modulation

2 votes
1 answer
67 views

Is a process matrix of rank $1$ unique?

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1 answer
51 views

How to show that the GHZ state is absolutely maximally entangled?

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1 answer
53 views

Can you apply a CNOT gate on qubits in MBQC that aren´t next to each other?

2 votes
2 answers
109 views

Preparation of logical state with qLDPC code

0 votes
1 answer
44 views

Netlist of the transpiled circuit in Qiskit

0 votes
1 answer
36 views

Frequency of qubits in qiskit simulators

4 votes
1 answer
189 views

How to characterize the extreme points of the set of CPTP maps?


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